With a digital camera 100, a photographed image 31 is displayed on a liquid crystal display and the user selects a desired image and specifies print specifications of the number of print sheets, a print paper size, a print color mode, etc., then print image data is prepared. The prepared print image data is transmitted from the digital camera 100 to a color printer of an output unit. An image is printed at the color printer in accordance with the print image data.

Digital Camera Claims

1. An apparatus for executing photoelectric conversion of image pickup light and then recording the conversion result as image data, the apparatus comprising: a display portion; a recording medium which records the image data; an image displaying unit which causes the display portion to display images sequentially; an image data selecting unit which selects image data corresponding to a desired image selected from the displayed images; an output method specification screen displaying unit which causes the display portion to display an output method specification screen, the output method specification screen being used for specifying a print specification including a number of copies of the selected image; and an image data transmitting unit which directly transmits output data prepared based on the selected image data and the specified number of copies to a printer.

2. The apparatus according to claim 1, wherein the output method specification screen displaying unit causes the display portion to display the number 1 as a default value for the number of copies in the output method specification screen.

3. The apparatus according to claim 2, further comprising a switch for changing the displayed number of copies in the output method specification screen.

4. The apparatus according to claim 3, wherein the switch includes a first button and a second button, and the number of copies increments by one as the first button is depressed, and decrements by one as the second button is depressed.

5. The apparatus according to claim 1, further comprising a switch for sequentially displaying the images, the switch being also used as a switch for specifying the number of copies.

6. The apparatus according to claim 1, wherein the images displayed correspond to reduced image data prepared based on the image data, and the images are sequentially displayed on the display portion in a fast scroll manner.

7. The apparatus according to claim 6, wherein the images displayed are images enlarged from the reduced image data.

8. The apparatus according to claim 1, wherein the displayed output method specification screen contains a plurality of print specification items including the number of copies, and the output method specification screen displaying unit includes a means for automatically moving from a first one of the print specification items to a next, second one of the print specification items when the first one of the print specification items has been set.

9. A print system comprising: a photoelectric conversion unit which executes photoelectric conversion of image pickup light; a printing unit which executes printing; a display portion; a recording medium which records the conversion result by the conversion unit as image data; an image displaying unit which causes the display portion to display images sequentially; an image data selecting unit which selects image data corresponding to a desired image selected from the displayed images; an output method specification screen displaying unit which causes the display portion to display an output method specification screen, the output method specification screen being used for specifying a print specification including a number of copies of the selected image; and an image data transmitting unit which directly transmits output data prepared based on the selected image data and the specified number of copies to the printing unit.

10. The print system according to claim 9, wherein the output method specification screen displaying unit causes the display portion to display the number 1 as a default value for the number of copies in the output method specification screen.

11. The print system according to claim 10, further comprising a switch for changing the displayed number of copies in the output method specification screen.

12. The print system according to claim 11, wherein the switch includes a first button and a second button, and the number of copies increments by one as the first button is depressed, and decrements by one as the second button is depressed.

13. The print system according to claim 9, further comprising a switch for displaying the images sequentially, the switch being also a switch for specifying the number of copies.

14. The print system according to claim 9, wherein the images displayed correspond to reduced image data prepared based on the image data, and the images are sequentially displayed on the display portion in a fast scroll manner.

15. The print system according to claim 14, wherein the images displayed sequentially are images enlarged from the reduced image data.

16. The print system according to claim 9, wherein the displayed output method specification screen contains a plurality of print specification items including the number of copies, and the output method specification screen displaying unit includes a means for automatically moving from a first one of the print specification items to a next, second one of the print specification items when the first one of the print specification items has been set.

17. A method, comprising: executing photoelectric conversion of image pickup light; recording the conversion result as image data in a recording medium; causing a display portion to display images sequentially; selecting image data corresponding to a desired image selected from the displayed images; causing the display portion to display an output method specification screen; specifying a print specification including a number of copies of the selected image; and directly transmitting output data prepared based on the selected image data and the specified number of copies from an apparatus to a printer.

18. The method according to claim 17, wherein the display portion displays the number 1 as a default value for the number of copies in the output method specification screen.

19. The method according to claim 18, further comprising changing the displayed number of copies in the output method specification screen by operating a switch.

20. The method according to claim 19, wherein the switch includes a first button and a second button, and the number of copies increments by one as the first button is depressed, and decrements by one as the second button is depressed.

21. The method according to claim 17, wherein a switch for displaying the images sequentially is also usable as a switch for specifying the number of copies.

22. The method according to claim 17, wherein the images displayed correspond to reduced image data prepared based on the image data, and the images are sequentially displayed on the display portion in a fast scroll manner.

23. The method according to claim 22, wherein the images displayed sequentially are images enlarged from the reduced image data.

24. The method according to claim 17, wherein: the displayed output method specification screen contains a plurality of print specification items including the number of copies, and the output method specification screen displaying unit includes a means for automatically moving from a first one of the print specification items to a next, second one of the print specification items when the first one of the print specification items has been set.

25. An apparatus for executing photoelectric conversion of image pickup light and then recording the conversion result as image data, the apparatus comprising: means for displaying; means for recording the image data; means for causing the means for displaying to display images sequentially means for selecting image data corresponding to a desired image selected from the displayed images; means for causing the means for displaying to display an output method specification screen, the output method specification screen being used for specifying a print specification including a number of copies of the selected image; and means for directly transmitting output data prepared based on the selected image data and the specified number of copies to an external printer.

26. The apparatus according to claim 25, wherein the means for causing the means for displaying to display an output method specification screen causes the means for display to display the number 1 as a default value for the number of copies in the output method specification screen.

27. The apparatus according to claim 26, further comprising a switch for changing the displayed number of copies in the output method specification screen.

28. The apparatus according to claim 27, wherein the switch includes a first button and a second button, and the number of copies increments by one as the first button is depressed, and decrements by one as the second button is depressed.

29. The apparatus according to claims 25, wherein the means for causing the means for displaying is also used for specifying the number of copies.

30. The apparatus according to claim 25, wherein: the images displayed correspond to reduced image data prepared based on the image data, and the images are sequentially displayed, on the means for displaying, in a fast scroll manner.

31. The apparatus according to claim 30, wherein the images displayed sequentially are images enlarged from the reduced image data.

32. The apparatus according to claim 25, wherein: the displayed output method specification screen contains a plurality of print specification items including the number of copies, and the means for causing the means for displaying to display an output method specification screen includes a means for automatically moving from a first one of the print specification items to a next, second one of the print specification items when the first one of the print specification items has been set.

Digital Camera Description

CROSS-REFERENCE OF THE APPLICATION

[0001] This is a continuation application Ser. No. 10/298,087 filed on Nov. 18, 2002, which is a continuation application Ser. No. 09/081,786 filed on May 20, 1998, which issued as U.S. Pat. No. 6,618,553 on Sep. 9, 2003; the disclosures of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] This invention relates to a digital camera and in particular to a digital camera capable of outputting image data directly to a printer and a printing system using the same.

[0004] 2. Related Art

[0005] In recent years, digital cameras (still-video cameras) have been developed, sold, and finding spreading use.

[0006] The digital camera is configured to execute photoelectric conversion of image pickup light to provide image data, record the image data on a recording medium, and output the recorded image data to an external image processing system such as a personal computer (PC). The external image processing system performs print image data preparation processing and outputs the prepared print image data to a printer for printing or reproducing the picked-up image on paper.

[0007] Most digital cameras comprise each a liquid crystal display for displaying the image pickup result and the image data provided by photoelectric conversion is compressed and recorded on a recording medium. To compress the image data, normally JPEG (Joint Photographic Expert Group) standard is applied.

[0008] To select an image on a PC, a number of thumbnail images compressed in JPEG (described later) are previously input and displayed on a monitor. The picked-up image data corresponding to a selected thumbnail image is input from the digital camera and is decompressed, then displayed on the monitor. When the user recognizes it, color print image data preparation processing is performed and the image is printed at a printer connected to the PC.

[0009] The thumbnail image is a reduced image used for the user to select a desired image out of the input image data on a PC, etc. For example, assuming that the size of 1-frame image data is 680.times.480 pixels, the corresponding thumbnail image is reduced by thinning out the data to about 80.times.60 pixels; the thumbnail images are recorded on a recording medium of the digital camera in a one-to-one correspondence with normal picked-up images.

[0010] When color print image data preparation processing is performed, print image data preparation processing is performed by programs on the PC to reproduce or print a color image (video) with high accuracy and bit map data is prepared for each print color required for drawing and is given to a printer together with a control signal for performing the color image reproduction operation on recording paper.

[0011] A color print ink jet printer capable of printing a high-quality image like a picture or a photo is developed and sold as a color printer.

[0012] The above-mentioned print image data preparation processing programs are contained in a program group called a printer driver in a data processing module 210 as shown In FIG. 11. A printer driver 220 normally comprises three modules of rasterizer, color correction, and halftone as means for obtaining binary data.

[0013] However, usually the PC comprises a large number of application programs other than image (video) print processing because of general versatility. The application programs and the above-mentioned printer driver operate under the control of windows, MS-DOS, etc., (PC operating system (OS) manufactured by Microsoft Corporation).

[0014] Therefore, to perform image print processing, the user needs to enter commands as specified by the OS for reading the print processing application program and the printer driver into PC internal memory from a storage unit storing them (for example, magnetic disk) and placing them in an executable state. However, it takes time (so-called overhead time) to enter commands and read the print processing application program and the printer driver; the overhead time requires several minutes at the shortest, thus it takes time to start.

[0015] Although PCs are finding remarkable spreading use, many problems remain to be solved for users to know how to actually handle PCs; it is also pointed out that most persons who have PCs cannot master them. If they attempt to install the image (video) print processing application program and the printer driver, they may find it difficult to install the software or may not understand how to enter the commands.

[0016] The need for using an expensive PC only for the purpose of printing picked-up images involves remarkable impairment of user’s convenience.

[0017] Examining demands for simplifying the print processing operation and reducing the overhead time almost to zero from the aspect of the digital camera, preferably, for example, image data can be output from the digital camera directly to a printer without intervention of a PC and a desired picked-up image can be printed on a desired number of print sheets in a desired paper size and print color mode. More preferably, an external unit to which image data is to be transmitted including a printer can be specified.

SUMMARY OF THE INVENTION

[0018] It is therefore an object of the invention to provide a digital camera having capabilities of outputting image data directly to an external system and printing a desired image under desired print specifications of the number of print sheets, paper size, mint color mode, etc. It is another object of the invention to provide a printing system using the digital camera.

[0019] According to one aspect of the invention, there is provided a digital camera for executing photoelectric conversion of image pickup light and then recording the conversion result as image data, the digital camera comprising a display section for displaying an image, a recording medium for recording the image data, image data selection means for selecting desired image data out of the recording medium, and output method specification means for outputting the selected image data to an external system under predetermined output specifications. The image data selection means reads the image data for each frame and adds an index to the image data for display on the display section.

[0020] According to another aspect of the invention, there is provided a digital camera for executing photoelectric conversion of image pickup light and then recording the conversion result as image data and thumbnail image data of the image data, the digital camera comprising a display section for displaying an image, a recording medium for recording the image data and the thumbnail image data, thumbnail image display means for reading the thumbnail image data from the recording medium and displaying thumbnail images on the display section, image data selection means for selecting one of the displayed thumbnail images, thereby selecting desired image data corresponding thereto, and output method specification means for outputting the selected image data to an external system under predetermined output specifications The thumbnail image display means enlarges and displays the thumbnail image.

[0021] According to another aspect of the invention, there is provided a digital camera for executing photoelectric conversion of image pickup light and then recording the conversion result as image data and thumbnail image data of the image data, the digital camera comprising a display section for displaying an image, a recording medium for recording the image data and the thumbnail image data, thumbnail image print means for printing out the thumbnail image data recorded on the recording medium at an external printer, thumbnail image display means for reading the thumbnail image data from the recording medium and displaying thumbnail images on the display section, image data selection means for selecting one of the displayed thumbnail images based on the printed thumbnail images, thereby selecting desired image data corresponding thereto, and output method specification means for outputting the selected image data to an external system under predetermined output specifications. The thumbnail image print means adds an index to each thumbnail image data piece and outputs to the external printer and the index of one of the indexed thumbnail images printed is specified, whereby the image data selection means selects desired image data corresponding thereto.

[0022] With the digital cameras according to the three aspects of the invention, the external system is a color printer and the predetermined output specifications contain at least one of the number of print copies, a print paper size, and a print color mode for printing the image data. The print color mode is full color, single color, or monochrome. The external system contains a printer or a facsimile or an image processing system connected by a communication line.

[0023] A printing system provided according to the invention comprises of the three types of digital cameras described above and a color printer as an external system.

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In the accompanying drawings:

[0025] FIGS. 1(a)-1(b) are block diagrams to show a configuration example of a digital camera of the invention;

[0026] FIG. 2 is a block diagram to show a configuration example of control means stored in ROM;

[0027] FIGS. 3(a)-3(d) are block diagrams to show a configuration example of image selection means,

[0028] FIG. 4 is a block diagram to show the relationship among image selection means, print image data preparation programs, and control means;

[0029] FIG. 5 is a flowchart to show brief operation of a control section;

[0030] FIG. 6 is a block diagram to show a configuration example of output method specification means;

[0031] FIGS. 7(a)-7(b) are examples of a rear part view of the digital camera;

[0032] FIG. 8 is a flowchart to show an operation example from image selection to print image data preparation;

[0033] FIG. 9 is a flowchart to show another operation example from image selection to print image data preparation;

[0034] FIG. 10 is a flowchart to show another operation example from image selection to print image data preparation; and

[0035] FIG. 11 is a block diagram to show an example of print image data preparation programs used to prepare print data on a personal computer.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0036] FIG. 1 is a block diagram to show a configuration example of a digital camera of the invention.

[0037] As shown in FIG. 1 a, a digital camera 100 comprises an optical system consisting of a lens, an iris mechanism, etc., through which reflected light from an image to be photographed is incident on a CCD 2, the CCD 2 for converting image pickup light from the optical system 1 into an electric signal, a signal processing section 3 for processing the signal from the CCD 2 and outputting the processed signal to a frame memory 6 as multiple-valued (R, G, B) raster data (image data), a control section 4 for controlling the operation of the signal processing section, frame memories 6 and 6′, a signal processing section 7, and a recording medium control section 8, image processing, image compression/decompression processing, etc., input means 5 for inputting a command entered by the user operating a switch, etc., converting the command into a digital signal, and feeding the digital signal into the control section 4, the signal processing section 7 for converting R, G, B raster data in the frame memory into brightness component Y and color difference components U and V, compressing the data in JPEG, and performing reduction processing for preparing a thumbnail image, a recording medium control section 8 for receiving output of the signal processing section 7 and controlling writing of the image data compressed in JPEG, which will be hereinafter referred to as JPEG image data, and thumbnail image data into predetermined locations of a recording medium 9 or an expanded recording medium 10, read of the recorded JPEG image data therefrom, etc., the recording medium 9 and expanded recording medium 10 for storing image data, an interface 11 used to transfer data to and from an external system, display means 15 of a LED lamp, etc., for displaying the switch state, functional specifications, etc., and display means 16 made of a liquid crystal display, etc., for displaying a photographed image or an object to be picked up. Display means 15 and display means 16 are examples of means for displaying.

[0038] The frame memory 6 normally is used as an image display memory of the liquid crystal display 16 and image data is expanded in bit map image. The frame memory 6′ normally is used as a menu display memory of the liquid crystal display 16. At the display time on the liquid crystal display 16, the contents of the frame memories 6 and 6′ are superimposed on each other on the display.

[0039] The recording medium 9 is made of a 4-MB flash memory fixed in the camera 100. It can be configured to record not only image data, but also programs, etc. Compact flash (trademarks of Sun Disk) having a capacity of 4-40 MB is used as the expanded recording medium 10 in the embodiment. The recording medium 9 and expanded recording medium 10 are examples of means for recording image data.

[0040] A serial interface is used as the interface 11 in the embodiment to receive a program sent from a computer such as a PC 200, transmit image data to the PC 200, send image data via a modem 150 to a communication line 160, etc., and transmit print image data to a printer 240 or a facsimile machine.

[0041] FIG. 1b shows the configuration of the control section 4 which consists of a CPU 41, a RAM 42, and a ROM 43. The ROM 43 stores control means 430 made up of programs required for operation control of the digital camera 100 and data processing in the digital camera such as data compression processing (FIG. 2).

[0042] Print data preparation programs including printer driver may be stored in the ROM 43. Alternatively, they can also be read from an external recording medium such as magnetic disk, CD-ROM, or a memory card into the recording medium 9 or the expanded recording medium 10 and be read therefrom for execution at a desired time.

[0043] FIG. 2 is a block diagram to show a configuration example of the control means 430 stored in the ROM 43. The control means 430 consists of means required for operation control of the digital camera 100, image data processing means required in the process of storing image data such as compression of image data, and means for decompressing compressed image data and preparing print data. Normally, the means are made of programs.

[0044] The control means 430 comprises a control system 431, input command determination means 432, an internal program group 433, external program reception means 434, data management means 435, and display data output means 436.

[0045] The control system 431 controls the whole operation of the digital camera 100, for example, an aperture motor drive section (not shown) in the optical system, the operation of the signal processing section 3, the frame memory 6, the signal processing section 7, and the recording medium control section 8, and execution of the input command determination means 432 to the display data output means 436.

[0046] When the user selects desired operation or processing by operating a switch, etc., disposed on the digital camera 100, the input command determination means 432 determines a digital signal output from the input means 5 and determines what the user-entered command operation is. According to the determination result, the input command determination means 432 transfers control to the corresponding program in the internal program group 433 or transfers control to the control system 431 for the external program reception means 434 to receive an external program.

[0047] The internal program group 433 consists of programs for controlling storage of picked-up image data in the recording medium 9, read or write of data from or into the expanded recording medium 10, LED display at the image picking up time, etc.,; the programs are contained in the ROM 43 as basic processing programs. For example, the internal programs include a JPEG compression program required for writing image data into the recording medium 9.

[0048] The external program reception means 434 is started when the input command determination means 432 outputs an external program introduction command.

[0049] The external program reception means 434 determines which of the PC or the like, the expanded recording medium 10, and the communication line a program is to be introduced from by the contents of the external program introduction command and performs corresponding reception processing, then transfers control to the data management means 435.

[0050] When picked-up image data is written into the recording medium 9, deleted, or added or program code introduced from the outside is written, deleted, or added, the data management means 435 performs data management equivalent to file management widely performed in a computer such as the PC.

[0051] The image data (data compressed in JPEG) and thumbnail image data are processed by the internal program 433 or its equivalent circuit and are written into the recording medium 9 by the recording medium control section 8.

[0052] The display data output means 436 outputs LED display data, image data, or display data of a menu, etc., to the LED display means 15 or the liquid crystal display 16 of the digital camera 100.

[0053] FIG. 3 is a block diagram to show a configuration example of image selection means 45.

[0054] Image selection means 45A shown in FIG. 3a comprises print image selection means 453 for displaying picked-up image data on the liquid crystal display 16 in order for the user to select a desired print image and output method specification means 454 for specifying print specifications of the number of print sheets, print paper size, print color mode (full color, single color, monochrome), etc., and an external system to which the image data is to be transmitted. (See first embodiment.)

[0055] Image selection means 45B shown in FIG. 3b comprises thumbnail image display means 452 for displaying thumbnail image data on the liquid crystal display 16 in a fast forward manner, print image selection means 453′ for requesting the user to select a desired image from among displayed thumbnail images and displaying the image data corresponding to the user-selected thumbnail image for the user to recognize it, and output method specification means 454 for specifying print specifications and an external system to which the image data is to be transmitted. (See second embodiment.) The output method specification means 454 is an example of a means for causing the means for displaying to display an output method specification screen.

[0056] Image selection means 45C shown in FIG. 3c comprises thumbnail image print means 452′ for adding index code to thumbnail image data and transmitting to a printer for printing thumbnail images, print image selection means 453” for displaying a thumbnail image selection screen on the liquid crystal display 16 for the user to specify a desired image based on the printed thumbnail images and displaying the specified image data for the user to recognize it, and output method specification means 454 for specifying print specifications and an external system to which the image data is to be transmitted. (See third embodiment.)

[0057] Image selection means 45D shown in FIG. 3d comprises additional image selection method specification means 451 for the user to select either the image selection means 45B or 45C.

[0058] The image selection means 45A, 45B, 45C, or 45D may be introduced from the outside or can also be stored in the ROM 43 as one of the internal programs 433 making up the control means 430 (FIG. 2). The output method specification means 454 has a setup value registration table comprising setup values and image index numbers provided in a one-to-one correspondence with each other.

[0059] FIG. 4 is a schematic representation to execute a direct print function for transmitting print image data to a printer, showing the relationship among the image selection means 45, the print image data preparation program group 50, and the control means 430. FIG. 5 is a flowchart to show the operation of the control section 4 when the direct print function is executed.

[0060] In FIG. 4 and FIG. 5, when the user turns on an image selection processing switch, the input command determination means 432 gives code meaning image selection to the control system 431, which then reads the image selection means (program) 45 from the ROM 43 or the recording medium 9 through the recording medium control section 8 at step P1.

[0061] When the image selection means 45 is expanded in the RAM 42, the control system 431 transfers control to the image selection means 45. When the user selects a desired image and specifies a desired output method, the image selection means 45 goes to step P3 if the external system to which image data is to be transmitted is the printer 240 or a facsimile machine. If the external system is the PC 200 or image data is sent to the communication line through the modem 150, the image selection means 45 goes to step P5 and transfers control to the control system 431 (P2).

[0062] The control system 431 gives an instruction for reading the print image data preparation program group 50 stored in the ROM 43 or the recording medium 9 through the recording medium control section 8. The programs (51, 52, 531, 532, 533, 54) in the print image data preparation program group 50 are read in the instruction order of the control system 431 and are expanded in the RAM 42 at step P3.

[0063] The control system 431 transfers control to the programs in the print image data preparation program group 50 in order for preparing print image data. At the termination of preparing the print image data at step P4, control goes to step P5. The 1-frame image data can also be divided into several blocks in the subscanning direction for preparing the print image data.

[0064] If the specified external system is the printer 240, the image data transmission means 54 transmits print image data and print control data via the interface 11 to the printer 240. If the specified external system is a facsimile machine, the image data transmission means 54 transmits monochrome print image data. If the external system is the PC 200 or image data is sent to the communication line through the modem 150, the image data transmission means 54 transmits image data or print image data and print control data at step P5. The interface 11 is an example of a means for directly transmitting the selected image data and the specified number of copies to an external printer.

[0065] UV components of the image data (YIN component data) transferred to the print image data preparation program group 50 are set to U=u and V=v (-1

[0066] The print image data preparation program group 50 contains a data decompression program 51 for decompressing compressed data read from the recording medium 9, an RGB conversion program 52 for converting image data consisting of YUV components into RGB components, a printer driver 53, and image data transmission program 54 for transmitting print data.

[0067] The printer driver 53 has the same configuration as a printer driver for preparing print data in PC, etc., and comprises three modules of rasterizer, color correction, and halftone to provide binary data.

[0068] Preferably, a color conversion parameter is added to the RGB conversion program 52 and a UV value conversion routine for setting U=0 and Y=0 at the preceding stage of RGB conversion when the color conversion parameter is set to a given value (for example, `0, 0`) is added.

[0069] The image data transmission program 54 can also be configured to transmit print image data with the digital camera 100 connected to the communication line through the modem connected to the interface 11. Further, it can also be configured to transmit print image data by wireless with the digital camera 100 connected to a radio unit such as a portable telephone through the modem connected to the interface 11.

[0070] FIG. 6 is a block diagram to show the configuration of the output method specification means 454. The output method specification means 454 comprises output method specification screen display means 4541 for displaying an output method specification screen for specifying print specifications and an external system to which image data is to be transmitted (FIG. 7b), number-of-print-sheets specification means 4542 for specifying the number of print sheets, print size specification means 4543 for specifying a print paper size, print color mode specification means 4544 for specifying a print color mode, and output unit specification means 4545 for specifying an external system to which image data is to be transmitted.

[0071] Preferably, the print size specification means 4543 comprises a table in which print paper sizes, such as A4, A6, and postcard or business card size, L format, and E format used with normal silver salt photos, are previously registered.

[0072] FIG. 7 shows an example of the rear part of the digital camera 100. The digital camera 100 is provided on the rear with the liquid crystal display 16 for displaying an image or a function menu, etc., buttons 19 and 20 for scrolling the screen of the liquid crystal display 16 up and down and from side to side, and function selection buttons 17 and 18. FIG. 7a provides an image display example and 7b provides an output method specification screen example.

Embodiment

[0073] Embodiments of image selection means 45 (45A, 45B, 45C, 45D) will be discussed.

First Embodiment

[0074] FIG. 8 is a flowchart to show an operation example of image selection means 45A. In the operation example, photographed image data pieces are displayed in order on a liquid crystal display and the user is requested to select a desired print image and specify print specifications of the number of print sheets, print paper size, print color mode (color, single color, or monochrome), etc., then print image data is prepared and transmitted to an external system.

[0075] When the image selection means 45A is transferred to a RAM 42, a control system 431 transfers control to the image selection means 45A. Print image selection means 453 reads 1-frame image data, transfers the image data to a frame memory 6, uses a data decompression program to decompose JPEG image data, and displays a candidate image 31 on a liquid crystal display 16 at step S1. In this case, an index number is added to the candidate image on the display.

[0076] If the user continues to press a button 19, the print image selection means 453 displays candidate images in order. When the user releases the button, the print image selection means 453 stops the display at the current image. If the user continues to press a button 20, the print image selection means 453 displays the preceding candidate images in order. When the user releases the button, the print image selection means 453 stops the display at the current candidate image at step S2.

[0077] If the user presses either the button 17 or 18, the print image selection means 453 assumes the candidate image to be selected and transfers control to output method specification means 454 at step S3.

[0078] The output method specification means 454 displays an output method specification menu as shown in FIG. 7b by output method specification screen display means 4541, prompting the user to select or enter the print specifications and the external system to which image data is to be transmitted.

[0079] At this time, initial display is, for example, “number of print sheets=1, print paper size=A4, print color mode=full color, output unit=color printer.” The inside of a box 21 that can be specified or selected is displayed in a color different from the colors of other boxes at step S4.

[0080] First, when the user presses the button 17 or 18, number-of-print-sheets specification means 4542 goes to a step for specifying the number of print sheets. Each time the user presses a button 19, the number of print sheets is incremented by one starting at the initial value and the resultant number of sheets is displayed. Each time the user presses a button 20, the number of print sheets displayed is decremented by one. If the user presses either the button 17 or 18, the current display value is set as the number of print sheets and is stored in the location corresponding to the image index number in a setup value registration table at step S5 and control goes to the next step.

[0081] When the user presses the button 17 or 18, print size specification means 4543 goes to a step for selecting a print paper size and displays the contents of a print size registration table in which print paper sizes are previously registered. If the user presses the button 19 or 20 to select a desired print paper size and presses the button 17 or 18, the selected print paper size is set and is stored in the location corresponding to the image index number in the setup value registration table at step S6 and control goes to the next step.

[0082] When the user presses the button 17 or 18, print color mode specification means 4544 goes to a step for selecting a print color mode and displays the contents of a print color mode registration table in which print color modes are previously registered. If the user presses the button 19 or 20 to select a desired print color mode and presses the button 17 or 18, the selected print color mode is set. If full color is selected as the print color mode, a print color mode parameter in an RGB conversion program 52 is set to 1. If a single color is selected as the print color mode, the print color mode parameter in the RGB conversion program 52 is set to 2. If monochrome is selected as the print color mode, the print color mode parameter in the RGB conversion program 52 is set to 3. The print color mode parameter is stored in the location corresponding to the image index number in the setup value registration table at step S7.

[0083] When the user presses the button 17 or 18, output unit specification means 4545 goes to a step for selecting an output unit and displays the contents of an output unit registration table in which output units are previously registered. If the user selects a color printer as the output unit, an output unit parameter in an image data transmission program 54 is set to 1. If the user selects a facsimile as the output unit, the output unit parameter in the image data transmission program 54 is set to 2. If the user selects a PC as the output unit, the output unit parameter in the image data transmission program 54 is set to 3. If the user selects a communication terminal as the output unit, the output unit parameter in the image data transmission program 54 is set to 4. If the user presses the button 17 or 18, the selected output unit is set and the setup value corresponding to the selected output unit is stored in the location corresponding to the image index number in the setup value registration table, then control returns to step S1 to display another candidate image. If another candidate image does not exist, the output unit parameter value is checked. If the value is 1 or 2, control goes to step S9; if the value is 3 or 4, control goes to step S16.

[0084] The control system 431 expands programs contained in a print image data preparation program group 50 in the RAM 42 in order and transfers control to a compressed data decompression program 51 at step S9.

[0085] The compressed data decompression program 51 reads image data (JPEG image data) selected by the print image selection means 453 into the RAM 42 and decompresses the data at step S10.

[0086] At the termination of decompressing the compressed image data, the RGB conversion program 52 checks the print color mode parameter at step S11. If the print color mode parameter has a value of 1, control goes to step S12. If the print color mode parameter has a value of 2, all UV components of the image data are converted into U=u and V=v. If the print color mode parameter has a value of 3, all UV components of the image data are converted into U=0 and V=0.

[0087] The RGB conversion program 52 converts the image data consisting of YUV components into image data consisting of R (red), G (green), and B (blue) components at step S12. When the UV components are U=u and V=v, the image data is converted into single-color image data. When the UV components are U=0 and V=0, the image data is converted into monochrome image data.

[0088] A rasterizer 531 converts the image data into RGB continuous-tone (for example, 256-gray-level) bit image data undergoing raster conversion for each of R, G, and B at step S13.

[0089] A color correction module 532 applies color correction processing to the RGB continuous-tone bit image data to relate the data to print colors and converts the data into CMYK continuous-tone bit image data for K (black), C (cyan), M (magenta), and Y (yellow) printing at step S14.

[0090] A halftone module 533 uses a dither method or an error diffusion method to perform halftone processing for the CMYK continuous-tone bit image data at step S15, whereby a bit map binarized for each color (binary data table) is prepared.

[0091] At the termination of the halftone processing, the image data transmission program 54 checks the print color mode parameter. If the value of the print color mode parameter is 1, the image data transmission program 54 transmits the setup values of the number of print sheets and the print paper size, a print control signal, and binary bit map data to a color ink jet printer 240, for example, through an interface 11 at step S16. The color ink jet printer 240 can receive the print control signal and print data directly from the digital camera 100 and print a desired number of sheets of the photographed image on recording paper of a desired size.

[0092] If the user specifies a single color or monochrome as the print color mode, the image is printed in the single color or monochrome if it is color-photographed. If the value of the print color mode parameter is 2, the image data transmission program 54 transmits the setup values of the number of print sheets and the print paper size, a print control signal, and binary bit map data to a facsimile through an interface 11. If the value of the print color mode parameter is 3 or 4, the image data transmission program 54 transmits JPEG image data or the setup values of the number of print sheets and the print paper size, a print control signal, and binary bit map data to PC 200 through the interface 11 or a terminal connected to a communication line 160 through a modem 150.

Second Embodiment

[0093] FIG. 9 is a flowchart to show an operation example of image selection means 45B (FIG. 3B) wherein thumbnail images are displayed and the user selects a desired image and specifies print specifications of the number of print sheets, print paper size, print color mode, etc., and an output unit to which image data is to be transmitted.

[0094] When the image selection means 45B is transferred to a RAM 42, a control system 431 transfers control to the image selection means 45B. Thumbnail image display means 452 reads all thumbnail image data and expands the data in the RAM 42 at step S21.

[0095] The thumbnail image display means 452 uses a data decompression program to decompose the thumbnail image data, enlarges the image data, adds an index number to the enlarged thumbnail image data, and displays the thumbnail image on a liquid crystal display 16 at step S22. A number of thumbnail images may be displayed on the liquid crystal display 16 without enlarging the thumbnail image data. The thumbnail image display menas 452 is an example of a means for sequentially reading the reduced image data from the means for recording.

[0096] Each time the user presses a button 19, print image selection means 453′ displays one enlarged thumbnail image. If the user stops pressing the button 19, the print image selection means 453′ continues to display the current thumbnail image. Each time the user presses a button 20, the print image selection means 453′ displays the preceding thumbnail image. If the user stops pressing the button 20, the print image selection means 453′ continues to display the current thumbnail image at step S23. Buttons 19 and 20 are examples of means for causing the means for displaying to display images in a quick scroll manner.

[0097] If the user stops pressing the button 19 or 20 and presses either the button 17 or 18 with the thumbnail image displayed, the print image selection means 453′ assumes the image to be selected. When the user selects images from among the thumbnail images and completes selection of desired images, the print image selection means 453′ transfers control to the control system 431. Buttons 17 and 18 are examples of means for selecting image data corresponding to a desired image data from the images displayed in the quick scroll manner.

[0098] The control system 431 transfers control to output method specification means 454. At step S25, the output method specification means 454 handles output method specification processing of print specifications, an output unit to which image data is to be transmitted, etc., and checks the value of an output unit parameter at step S25. If the parameter value is 1 or 2, control goes to step S26; if the parameter value 3 or 4, control goes to step S27.

[0099] The control system 431 expands print image data and programs contained in a print image data preparation program group 50 in the RAM 42 in order and transfers control to the print image data preparation program group 50 at step S26.

[0100] The print image data preparation program group 50 performs similar processing to steps S10 to S15 in FIG. 8, namely, performs decompression processing of image data (JPEG image data) selected by the print image selection means 453′, RGB conversion processing, rasterizing, color correction processing, and halftone processing at step S27.

[0101] At the termination of the halftone processing, as at step S16 in FIG. 8, an image data transmission program 54 checks the output unit parameter and transmits the print image data or JPEG image data to the specified output unit at step S28.

Third Embodiment

[0102] FIG. 10 is a flowchart to show an operation example of image selection means 45C (FIG. 3c) wherein thumbnail image data is printed at a printer and the user selects a desired image from among the printed thumbnail images and specifies print specifications of the number of print sheets, print paper size, print color mode, etc., and an output unit to which image data is to be transmitted.

[0103] A control system 431 expands programs contained in a print image data preparation program group 50 in a RAM 42 in order and transfers control to the image selection means 45C at step S31.

[0104] Thumbnail image print means 452′ reads all thumbnail image data, expands the image data in the RAM 42, decompresses the thumbnail image data in the RAM 42, and adds an index number to each thumbnail image data piece at step S32.

[0105] As described at steps S12 to S15 in FIG. 8, the print image data preparation program group 50 performs RGB conversion processing, rasterize processing, color correction processing, and halftone processing to prepare print thumbnail image data and transmits the image data to a printer 240 at step S33. In this case, the thumbnail image print means 452′ may set U and V components of the thumbnail image data in the RAM 42 to U=0 and V=0 to print a monochrome thumbnail image at the printer 240.

[0106] Thumbnail images each with an index number are printed at the printer 240 at step S34. Print image selection means 453” displays a message on a liquid crystal display, prompting the user to select a desired image from among the printed thumbnail images and enter the index number of the selected image at step S35.

[0107] If the user presses a button 19 as many times as the number of digits of the index number of the desired image and then presses a button 17 or 18, the print image selection means 453” reads the image data corresponding to the index number from a recording medium 9 into a frame memory 6 and displays the image on a liquid crystal display 16 at step S36.

[0108] If the user furthermore presses the button 17 or 18, the print image selection means 453” assumes the image to be selected and transfers control to output method specification means 454 at step S37.

[0109] The output method specification means 454 handles setting of print specifications and specification of an output unit to which image data is to be transmitted at step S38 as at steps S4 to S8 in FIG. 8. To select another candidate image, control returns to step S35. If another candidate image does not exist, the value of an output unit parameter is checked. If the parameter value is 1 or 2, control goes to step S39; if the parameter value is 3 or 4, control goes to step S40.

[0110] The print image data preparation program group 50 performs decompression processing of selected image data (JPEG image data), RGB conversion processing, rasterize processing, color correction processing, and halftone processing at step S39 as at steps S10 to S15 in FIG. 8.

[0111] At the termination of the halftone processing, as at step S16 in FIG. 8, an image data transmission program 54 checks the output unit parameter and transmits the print image data or JPEG image data to the specified output unit at step S40.

[0112] It is understood that the foregoing description is preferred embodiments of the invention and that various changes and modifications may be made in the invention without departing from the spirit and scope thereof.

[0113] As described above, according to the invention, images are displayed on display means such as a liquid crystal display of the digital camera and the user selects a desired image from among the displayed images and specifies the print specifications of the number of print sheets, a print paper size, a print color mode, etc., then can transmit the print image data prepared based on the user’s selection and specification from the digital camera to a printer. Therefore, a photographed image can be printed without intervention of another processing system such as a PC and it can be expected that digital cameras will come into wider use for those who do not have a PC, etc., or who have a PC, but are unfamiliar with handling the PC.

In the digital camera that can be used in connection to a mobile phone or other mobile electronic devices and the system thereof, a battery mounted in each device is shared to allow power to be supplied between the devices, and allow both devices to be used for longer hours. The digital camera and the mobile phone are electrically connectable by a connection cable. Generally, a power supply selection switch is set to A, and a power supply selection switch is set to D. The digital camera receives power supplied from a battery, and the mobile phone receives power supplied form a battery. From this state, when the power supply selection switch is switched to C, power is supplied from the battery to the mobile phone. On the other hand, when the power supply selection switch is set to B, and the power supply selection switch is set to D, power is supplied from the battery of the mobile phone to the digital camera.

Digital Camera Claims

1. A digital camera connectable to a mobile electronic device capable of being driven by a battery, the digital camera comprising: a first battery which provides a supply source of power necessary to operate the digital camera; a connecting unit which electrically connects to the mobile electronic device; a power input terminal which receives power supplied from a second battery mounted in the mobile electronic device connected via the connecting unit; and a power supply selection device which selectively switches a power supply such that power is supplied from one of the first battery and the second battery.

2. The digital camera according to claim 1, further comprising a power output terminal capable of supplying power from the second battery to the mobile electronic device connected via the connecting unit.

3. The digital camera according to claim 2, wherein the connecting unit is also used as a remote control connecting unit to which a remote control device is connected.

4-10. (canceled)

11. The digital camera according to claim 1, wherein the connecting unit is also used as a remote control connecting unit to which a remote control device is connected.

12-18. (canceled)

19. A digital camera connectable to a mobile electronic device capable of being driven by a battery, the digital camera comprising: a battery which provides a supply source of power necessary to operate the digital camera; a connecting unit which electrically connects to the mobile electronic device; and a power output terminal capable of supplying power from the battery mounted in the digital camera to the mobile electronic device connected via the connecting unit.

20. The digital camera according to claim 19, wherein the connecting unit is also used as a remote control connecting unit to which a remote control device is connected.

21. A digital camera system capable of transferring image data by connecting a mobile electronic device capable of being driven by a battery and a digital camera, wherein: the digital camera comprises: a first battery which provides a supply source of power necessary to operate the digital camera; a first connecting unit which electrically connects to the mobile electronic device; a first power input terminal which receives power supplied from a second battery mounted in the mobile electronic device connected via the first connecting unit; a first power supply selection device which selectively switches a power supply such that power is supplied from one of the first battery and the second battery; and a first power output terminal capable of supplying power from the first battery to the mobile electronic device connected via the first connecting unit; the mobile electronic device comprises: a second battery which provides a supply source of power necessary to operate the mobile device; a second connecting unit which electrically connects to the digital camera; a second power input terminal which receives power supplied from the first battery mounted in the digital camera connected via the second connecting unit; a second power supply selection device which selectively switches a power supply such that power is supplied from one of the first battery and the second battery; and a second power output terminal capable of supplying power from the second battery to the digital camera connected via the second connecting unit; and the first connecting unit and the second connecting unit are used so that the first power input terminal and the second power output terminal are connected and the first power output terminal and the second power input terminal are connected to allow power to be supplied between the digital camera and the mobile electronic device.

Digital Camera Description

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a digital camera and a system thereof, and more particularly to a digital camera and a system thereof that can be used in connection to a mobile electronic device such as a mobile phone or a Personal Digital Assistant (PDA).

[0003] 2. Description of the Related Art

[0004] Systems have been proposed which allow a mobile phone and a digital camera to be used in connection to each other (Japanese Utility Model Registration No. 3074054, Japanese Patent Application Publication No. 2000-197161). In these systems, a battery is mounted to each of the mobile phone and the digital camera, and power is separately supplied. A digital camera of a plug connection type disclosed in Japanese Utility Model Registration No. 3074054 has no battery, and power for the camera is supplied from a mobile phone.

[0005] However, in the conventional systems, if the battery of either the mobile phone or the digital camera is drained and cannot supply necessary power, the device naturally cannot be used.

SUMMARY OF THE INVENTION

[0006] The present invention is achieved in view of the above, and has an object to provide a digital camera and a system of the same that can be used in connection to a mobile phone or other mobile electronic devices, wherein even if a battery of either the mobile phone or the digital camera is drained, a power supply is shared to allow use of both devices.

[0007] In order to attain the above described object, the present invention is directed to a digital camera connectable to a mobile electronic device capable of being driven by a battery, the digital camera comprising: a first battery which provides a supply source of power necessary to operate the digital camera; a connecting unit which electrically connects to the mobile electronic device; a power input terminal which receives power supplied from a second battery mounted in the mobile electronic device connected via the connecting unit; and a power supply selection device which selectively switches a power supply such that power is supplied from one of the first battery and the second battery.

[0008] According to the present invention, the digital camera is connectable to the mobile electronic device via the connecting unit. When the first battery mounted in the digital camera is drained and cannot drive the camera, a power supply source is switched by a power supply selection device, and power is supplied from the second battery of the mobile electronic device to the digital camera. This allows the digital camera to operate. The power supply selection device may be a selection device which can be manually operated, or may be a selection device which is automatically switched by a control signal.

[0009] Preferably, the digital camera further comprises a power output terminal capable of supplying power from the second battery to the mobile electronic device connected via the connecting unit. Thus, the digital camera and the mobile electronic device can share their batteries with each other, so that the digital camera and the mobile electronic device can be generally operated by their respective batteries independently, but when one of the batteries is drained, power is supplied from the other battery to allow operation.

[0010] The present invention is also directed to a digital camera connectable to a mobile electronic device capable of being driven by a battery, the digital camera comprising: a battery which provides a supply source of power necessary to operate the digital camera; a connecting unit which electrically connects to the mobile electronic device; and a power output terminal capable of supplying power from the battery mounted in the digital camera to the mobile electronic device connected via the connecting unit.

[0011] According to the present invention, the digital camera is connectable to the mobile electronic device via the connecting unit. When the battery mounted in the mobile electronic device is drained to prevent the mobile electronic device from being used, the digital camera is connected to the mobile electronic device, thus allowing power to be supplied from the battery of the digital camera to the mobile electronic device. This allows the mobile electronic device to operate.

[0012] Preferably, the connecting unit is also used as a remote control connecting unit to which a remote control device is connected.

[0013] Preferably, the digital camera further comprises: a detecting device which detects the power supply selected by the power supply selection device; and a control device which operates to reduce power consumption of the digital camera when the detecting device detects a state where the power is supplied from the second battery to the digital camera.

[0014] Preferably, as the operation to reduce the power consumption of the digital camera, the control device performs at least one of operations comprising supplying power to an image display device, stopping supplying power to a flash circuit, and reducing a clock operation frequency.

[0015] Preferably, the control device supplies power to an image pickup circuit system only when the detecting device detects the state where the power is supplied from the second battery to the digital camera and the digital camera is set to an image-capturing mode.

[0016] The image pickup circuit system includes an image pickup device which converts an optical image to an electric signal, and an analog signal processing circuit which performs sampling, color separation, and gain control, of an image signal output from the image pickup device.

[0017] Preferably, the digital camera further comprises a communication device which sends power supply switching information to the mobile electronic device when the detecting device detects the state where the power is supplied from the second battery to the digital camera.

[0018] Preferably, the digital camera further comprises: a battery remaining amount determining device which determines remaining amount of the first battery; and a power supply switching control device which automatically controls switching the first power supply selection device such that power is supplied from the second battery when the battery remaining amount determining device determines that the remaining amount of the first battery is below a predetermined reference value.

[0019] The present invention is also directed to a digital camera system capable of transferring image data by connecting a mobile electronic device capable of being driven by a battery and a digital camera, wherein: the digital camera comprises: a first battery which provides a supply source of power necessary to operate the digital camera; a first connecting unit which electrically connects to the mobile electronic device; a first power input terminal which receives power supplied from a second battery mounted in the mobile electronic device connected via the first connecting unit; a first power supply selection device which selectively switches a power supply such that power is supplied from one of the first battery and the second battery; and a first power output terminal capable of supplying power from the first battery to the mobile electronic device connected via the first connecting unit; the mobile electronic device comprises: a second battery which provides a supply source of power necessary to operate the mobile device; a second connecting unit which electrically connects to the digital camera; a second power input terminal which receives power supplied from the first battery mounted in the digital camera connected via the second connecting unit; a second power supply selection device which selectively switches a power supply such that power is supplied from one of the first battery and the second battery; and a second power output terminal capable of supplying power from the second battery to the digital camera connected via the second connecting unit; and the first connecting unit and the second connecting unit are used so that the first power input terminal and the second power output terminal are connected and the first power output terminal and the second power input terminal are connected to allow power to be supplied between the digital camera and the mobile electronic device.

[0020] According to the present invention, in the system where the mobile electronic device and the digital camera are connectable, both power supplies can be shared, so that if one of the batteries is drained, power is supplied from the other battery to allow operation.

[0021] Preferably, a circuit is configured such that the first battery and the second battery are not electrically connected to each other in any setting states of the first power supply selection device and the second power supply selection device.

[0022] Preferably, the digital camera further comprises: a detecting device which detects the power supply selected by the first power supply selection device; a first control device which operates to reduce power consumption of the digital camera when the detecting device detects a state where the power is supplied from the second battery to the digital camera; and a communication device which sends power supply switching information to the mobile electronic device when the detecting device detects the state where the power is supplied from the second battery to the digital camera; and the mobile electronic device further comprises: a second control device which operates to reduce power consumption of the mobile electronic device based on the power supply switching information sent from the digital camera.

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The nature of this invention, as well as other objects and advantages thereof, will be explained in the following with reference to the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures and wherein:

[0024] FIG. 1 shows a connection state between a digital camera and a mobile phone according to an embodiment of the invention;

[0025] FIG. 2 shows a circuit of essential portions and a connection relationship between the digital camera and the mobile phone;

[0026] FIG. 3 shows a circuit of essential portions according to another embodiment;

[0027] FIG. 4 is a block diagram of internal configurations of the digital camera and the mobile phone shown in FIG. 3;

[0028] FIG. 5 is a flowchart of a control procedure of the digital camera of this embodiment;

[0029] FIG. 6 is a flowchart of a control procedure of automatic switching of power supplies;

[0030] FIG. 7 shows a circuit of essential portions and a state where the mobile phone is connected to the digital camera; and

[0031] FIG. 8 shows a circuit of essential portions and a state where a remote control device is connected to the digital camera.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] Now, preferred embodiments of a digital camera and a system of the same according to the invention will be described with reference to the accompanying drawings.

[0033] FIG. 1 shows a connection state between a digital camera and a mobile phone according to an embodiment of the invention. A digital camera 10 has a shutter-release button 12 on its top, and image data taken in accordance with pressing the shutter-release button 12 is recorded in a recording medium such as a memory card 14. For the recording medium, various media can be used such as SmartMedia (Solid-State Floppy Disk Card), a PC card, CompactFlash, a magnetic disk, an optical disk, a magneto-optical disk, or Memory Stick. A signal processing device and a media interface in accordance with a medium to be used are applied. Not only a removable medium, but also a recording medium included in the digital camera 10 (internal memory) may be used.

[0034] The camera has, on its rear, a finder 16, a power supply switch 17, a liquid crystal monitor (LCD) 18, a mode selection switch 19, a display panel 20, a cross button 21, a menu/enter button 22, a cancel button 23, and a power supply selection switch 24 (SW 1). The power supply switch 17 is an operating unit for turning on/off a main power supply of the digital camera 10. The mode selection switch 19 is a mode setting device which can be selectively switched between an image-capturing mode and a reproduction mode. The display panel 20 includes a small liquid crystal display which mainly displays texts or simple symbols such as mode information or the number of possible images to be captured.

[0035] The cross button 21 is a multifunction operating unit which can input instructions of four directions: left, right, top, and bottom. A left key functions as a one frame reversing button, a right key functions as a one frame forwarding button in playback mode, and a top key and a bottom key are used as zoom keys for adjusting zoom in a playback zoom function or an electronic zoom function in image-capturing. The cross button 21 also function as an operation button for selecting menu items from a menu screen displayed by pressing the menu/enter button 22 and for instructing to select various setting items in each menu. The menu/enter button 22 is used when moving from a normal screen to a menu screen in each mode, or when confirming selection contents, instructing to perform (confirm) processing, or the like. The cancel button 23 is used when canceling an item selected from the menu, or returning to a previous operation state.

[0036] The liquid crystal monitor 18 can be used as an electronic finder for confirming an angle of view in image-capturing, and display a preview of a captured image or a reproduced image read from the memory card 14. Selecting the menu by the cross button 21 and setting the various setting items are performed using a display screen of the liquid crystal monitor 18. Further, the liquid crystal monitor 18 displays information such as the number of possible frames to be captured (for moving images, possible hours for image-capturing), a number of a reproduced frame, presence or absence of flash firing, macro mode, recording quality, or the number of pixels.

[0037] The camera has, on its bottom, a media slot (not shown) into which the memory card 14 is inserted, and a battery insert port (not shown) into which a battery 26 is inserted. Generally, the power supply selection switch 24 of the digital camera 10 is set to A, and the digital camera 10 receives power supplied from the battery 26, but switching the power supply selection switch 24 to B as required allows the digital camera 10 to receive power from a battery 42 of a mobile phone 40.

[0038] The camera has, on its side, a connector 28 which electrically connects to the mobile phone 40, and a voice output terminal (earphone jack) 29.

[0039] The mobile phone 40 also has a connector 44 which electrically connects to the digital camera 10, and one plug 51 of a connection cable 50 is inserted into the connector 44 of the mobile phone 40, and the other plug 52 is inserted into the connector 28 of the digital camera 10, thereby providing electrical connection between the digital camera 10 and the mobile phone 40 via the connection cable 50.

[0040] The mobile phone 40 has an antenna 45, a liquid crystal display unit 46, an operation key 47, and a power supply selection switch 48 (SW2), and the rechargeable battery 42 is mounted to its rear. Generally, the power supply selection switch 48 of the mobile phone 40 is set to D, and the mobile phone 40 receives power supplied from the battery 42, but switching the power supply selection switch 48 to C as required allows the mobile phone 40 to receive power from the battery 26 of the digital camera 10.

[0041] FIG. 2 shows a circuit of essential portions and a connection relationship between the digital camera 10 and the mobile phone 40. A first pin PD1 of the connector 28 in the digital camera 10 connects to the ground (GND). A second pin PD2 connects to a cathode of the battery 26 and a contact A terminal of the power supply selection switch 24. A third pin PD3 connects to a contact B terminal of the power supply selection switch 24. A fourth pin PD4 and a fifth pin PD5 connect to an internal circuit 56 of the digital camera 10, and are used as data transfer lines. A movable armature terminal 24C of the power supply selection switch 24 connects to a DC/DC converter 58, and a power supply voltage applied to the movable armature terminal 24C is converted to a required voltage by the DC/DC converter 58 and then supplied to the internal circuit 56.

[0042] A first pin PC1 of the connector 44 in the mobile phone 40 connects to the ground (GND). A second pin PC2 connects to a contact C terminal of the power supply selection switch 48. A third pin PC3 connects to a cathode of the battery 42 and a contact D terminal of the power supply selection switch 48. A fourth pin PC4 and a fifth pin PC5 connect to an internal circuit 60 of the mobile phone 40, and are used as data transfer lines. A movable armature terminal 48E of the power supply selection switch 48 connects to a DC/DC converter 62, and a power supply voltage applied to the movable armature terminal 48E is converted to a required voltage by the DC/DC converter 62 and then supplied to the internal circuit 60.

[0043] The digital camera 10 and the mobile phone 40 are connected using the multi-conductor connection cable 50 to provide connections between the pins with the same numbers. When the power supply selection switch 24 of the digital camera 10 is set to A, and the power supply selection switch 48 of the mobile phone 40 is set to C, power is supplied from the battery 26 of the digital camera 10 to the mobile phone 40. At this time, the battery 42 of the mobile phone 40 is detached.

[0044] When the power supply selection switch 24 of the digital camera 10 is set to B, and the power supply selection switch 48 of the mobile phone 40 is set to D, power is supplied from the battery 42 of the mobile phone 40 to the digital camera 10. At this time, the battery 26 of the digital camera 10 is detached.

[0045] When the power supply selection switch 24 of the digital camera 10 is set to B, and the power supply selection switch 48 of the mobile phone 40 is set to C, both batteries 26, 42 are detached. When the power supply selection switch 24 of the digital camera 10 is set to A, and the power supply selection switch 48 of the mobile phone 40 is set to D, power of the digital camera 10 is supplied from the battery 26, and power of the mobile phone 40 is supplied from the battery 42.

[0046] Thus, any combinations of settings of the power supply selection switches 24, 48 do not cause electrical connection between the batteries 26, 42. If the batteries 26, 42 were electrically connected, a short would be caused with a risk of destruction or fire. To avoid such a risk, it is necessary that any setting states of the power supply selection switches 24, 48 do not cause direct connection between the batteries 26, 42.

[0047] In FIGS. 1 and 2, the power supply selection switches 24, 48 are mechanical switches, but instead, switches using a semiconductor may be used. Further, power supplying paths may be switched by setting from the menu screen displayed on the liquid crystal monitor 18 or the liquid crystal display unit 46.

[0048] FIG. 3 shows a circuit of essential portions according to another embodiment. In FIG. 3, similar parts as in FIG. 2 are denoted by the same reference numerals, and descriptions thereof are omitted. In FIG. 3, a detection switch 66 (SW3) is added which detects a power supply source in the digital camera 10. The detection switch 66 and the power supply selection switch 24 are interlocking switches, and the detection switch 66 is used for detecting whether the digital camera 10 receives power supplied from an outside (mobile phone 40). One contact E terminal of the detection switch 66 connects to an output terminal of the DC/DC converter 58 via a resistance R1, and the other contact F terminal of the detection switch 66 connects to the ground. When the power supply selection switch 24 is set to B (that is, the digital camera 10 receives the power supplied from the battery 42 of the mobile phone 40), a movable armature of the detection switch 66 contacts the contact F terminal, and a movable armature terminal 66G connects to the ground. Thus, an L (Low) signal as a detected signal is input to the internal circuit 56.

[0049] On the other hand, when the power supply selection switch 24 is set to A, the movable armature of the detection switch 66 connects to the contact E terminal, and an output voltage Vcc of the DC/DC converter 58 is applied to the movable armature terminal 66G. Thus, an H (High) signal as a detected signal is input to the internal circuit 56.

[0050] The detection switch 66 is provided in order to detect the state where the power is supplied from the mobile phone 40 to the digital camera 10. Generally, power consumption of the digital camera 10 is higher than that of the mobile phone 40, and the battery 26 of the digital camera 10 has a capacity about twice as high as that of the battery 42 of the mobile phone 40. Thus, the state where the power is supplied from the mobile phone 40 to the digital camera 10 places a heavy current load on the battery 42 of the mobile phone 40, causing a problem of significant reduction in a power supply voltage, or the like.

[0051] In this embodiment, when the state where the power is supplied from the mobile phone 40 to the digital camera 10 is detected, control is performed to simultaneously operate to reduce the power consumption of the digital camera 10 (move to a lower power consumption mode). For example, (1) an operation of the liquid crystal monitor 18 is stopped (backlight OFF), (2) charging to a flash circuit is stopped, and (3) a clock operation frequency in the camera is reduced. These controls achieve reduction in power consumption.

[0052] When the above described state is detected, the data transfer lines (fourth pin and fifth pin) of the connection cable 50 are used to generate a command to reduce power, from the digital camera 10 to the mobile phone 40. The mobile phone 40 receives the command, and is automatically set to a mode of reducing power consumption (low power consumption mode), or controlled to turn off the power supply of the mobile phone 40. Thus, it is preferable to reduce the power consumption of the mobile phone 40 and concentrate the power of the battery 42 on the digital camera 10.

[0053] FIG. 4 is a block diagram of internal configurations of the digital camera 10 and the mobile phone 40 shown in FIG. 3. The battery 42 mounted to the mobile phone 40 connects to the power supply selection switch 48 (SW2), and connects to the power supply selection switch 24 (SW1) of the digital camera 10 via the connection cable 50. Likewise, the battery 26 mounted to the digital camera 10 connects to the power supply selection switch 24, and connects to the power supply selection switch 48 of the mobile phone 40 via the connection cable 50.

[0054] As described above, the connections of the batteries 26, 42 as the power supply sources are switched by the power supply selection switches 24, 48. The voltage of the battery 26 or the battery 42 selected by the power supply selection switch 48 of the mobile phone 40 is applied to a power supply unit 68 in the mobile phone 40. The power supply unit 68 is a block including the DC/DC converter 62 illustrated in FIG. 3, and a battery voltage applied to the power supply unit 68 shown in FIG. 4 is converted to a required voltage by the power supply unit 68 and then supplied to a signal processing circuit 70 and other blocks. The signal processing circuit 70 is a circuit block such as a voice signal processing circuit, which performs various processings necessary for the function of the mobile phone.

[0055] The mobile phone 40 includes an external interface 71 for communication with the digital camera 10 and other external devices, and a microprocessing unit (MPU) 72 as a control unit.

[0056] On the other hand, the digital camera 10 includes an external interface 81 for communication with the mobile phone 40 and other external devices, and a microprocessing unit (MPU) 82 as a camera control unit. The external interfaces 71, 81 correspond to the connectors 44, 28 illustrated in FIG. 1. As the external interfaces 71, 81, various interfaces can be applied such as a serial port, USB, IrDA, IEEE 1394, or other serial interfaces or parallel interfaces.

[0057] The MPU 82 of the digital camera 10 shown in FIG. 4 controls, based on instruction signals from the mode selection switch 19 and various operating units 84, operations of corresponding circuits, display on the liquid crystal monitor 18, flash firing, auto focus (AF), automatic exposure (AE), image-capturing operation, recording processing, or the like. A block of the operating unit 84 includes various operation keys such as the shutter-release button 12, the cross button 21, the menu/enter button 22, or the cancel button 23 illustrated in FIG. 1.

[0058] As shown in FIG. 4, the voltage of the battery 26 or the battery 42 selected by the power supply selection switch 24 of the digital camera 10 is applied to a power supply unit 85 in the camera. The power supply unit 85 is a block including the DC/DC converter 58 illustrated in FIG. 3. The battery voltage applied to the power supply unit 85 shown in FIG. 4 is converted to a required voltage by the power supply unit 85 and then supplied to each circuit block via power supply control switches SW11, SW12, SW13, SW14, SW15, SW16 and SW17 (hereinafter referred to as the power supply control switches SW11 to SW17).

[0059] The detected signal of the detection switch 66 interlocked with the power supply selection switch 24 is input to the MPU 82, and the MPU 82 distinguishes between the battery 26 and the battery 42 as the power supply source based on the detected signal received. When detecting the state where the power is supplied from the battery 42 of the mobile phone 40, the MPU 82 monitors a voltage value of the battery 42. Thus, the MPU 82 controls operations of the power supply control switches SW 11 to SW 17, and a frequency dividing ratio of a frequency divider circuit 86, based on the detected signal from the detection switch 66 and information on the voltage value of the battery 42 (voltage a).

[0060] The power supply switch SW 11 is a switch for selecting supply or interruption (ON/OFF) of power to display system circuits including the liquid crystal monitor 18 and an LCD controller 88. The power supply switch SW12 is a switch for selecting supply or interruption of power to a flash circuit 89. The flash circuit 89 is a block including a condenser, a charging circuit, a firing control circuit, or the like. The power supply switch SW 13 is a switch for selecting supply or interruption of power to image pickup system circuits including an image pickup device 90 and an image pickup signal processing circuit 91. The power supply switch SW14 is a switch for selecting supply or interruption of power to a picture signal generating circuit 94 for outputting a picture signal to an image output unit (video terminal) 93. The power supply switch SW15 is a switch for selecting supply or interruption of power to a voice input unit including a voice input unit (microphone) 96 and a voice signal processing circuit 97. The power supply switch SW16 is a switch for selecting supply or interruption of power to a voice output circuit 100 for outputting voice from a voice output unit (speaker) 99. The power supply switch SW17 is a switch for selecting supply or interruption of power to a digital signal processor (DSP) 102.

[0061] The frequency divider circuit 86 is a circuit which switches the frequency dividing ratio to 1/1, 1/2, 1/4, 1/8, 1/16, . . . by a control signal from the MPU 82, and provides the DSP 102 with a clock signal obtained by frequency dividing a clock signal from a crystal oscillator 104 by a designated frequency dividing ratio.

[0062] Operations of the digital camera 10 will be outlined below. A light having passed through a taking lens 106 is subjected to light amount adjustment by a shutter and aperture mechanism 108, and then enters the image pickup device 90. As the image pickup device 90, various devices such as a CCD image sensor or a CMOS image sensor can be applied. Many photosensors are arranged on a light-receiving surface of the image pickup device 90 in two dimensions, and a subject image focused on the light-receiving surface is converted to signal charge of amount corresponding to the amount of entering light by each photosensor.

[0063] The signal charge accumulated in each photosensor of the image pickup device 90 is successively read out as voltage signals (image signals) in accordance with the signal charge based on pulses provided from an unshown drive circuit, and sent to the image pickup signal processing circuit 91. The image pickup signal processing circuit 91 includes an analog signal processing circuit such as a sampling hold circuit, a color separation circuit, a gain control circuit, and an A/D converter. In the image pickup signal processing circuit 91, the voltage signals are subjected to correlation double sampling (CDS), color separation into color signals of R, G, B, and gain control of a level of each color signal, and then converted to digital signals by the A/D converter.

[0064] Digital image signals output from the image pickup signal processing circuit 91 are sent to the DSP 102. The DSP 102 is a signal processing block having image signal processing units such as a luminance/color-difference signal generation circuit, a gamma correction circuit, a sharpness correction circuit, a white balance correction circuit, and various signal processing unit such as a compression/decompression processing unit, a filing processing unit, an encryption/decoding processing unit, a memory control unit, a recording/reproducing processing unit. Image data sent from the image pickup signal processing circuit 91 to the DSP 102 is converted to luminance signals (Y signals) and color-difference signals (Cr, Cb signals) in the DSP 102, and subjected to a predetermined processing such as gamma correction, then stored in an internal memory 110.

[0065] When the captured image is to be displayed and output, the image data is read from the internal memory 110, and converted to picture signals in a predetermined display format via the DSP 102. The picture signals thus obtained are output to the liquid crystal monitor 18 via the LCD controller 88. The image data in the internal memory 110 is rewritten at regular intervals by the image signals captured from the image pickup device 90, and the picture signals generated from the image data are fed to the liquid crystal monitor 18, thus causing the liquid crystal monitor 18 to display a captured picture (live image). It is possible to transfer this picture to the mobile phone 40 and display it on the liquid crystal display unit 46 of the mobile phone 40.

[0066] Pressing the shutter-release button 12 in the operating unit 84 causes an instruction signal to start image-capturing to be generated. The MPU 82 detects the instruction signal and performs an image pickup operation for recording. Specifically, the MPU 82 performs various calculations such as focus evaluation calculation or AE calculation from the image data captured in response to “half press (S1=ON)” of the shutter-release button 12, controls an unshown lens driving unit based on the calculation results to move the taking lens 106 to a focusing position, while controls the shutter and aperture mechanism 108, and controls charge accumulation time of the image pickup device 90.

[0067] The MPU 82 controls the image pickup system circuit in response to receiving the image-capturing start signal by “full press (S2=ON)” of the shutter-release button 12, starts capturing the image data for recording, and sends a command to the compression/decompression circuit in the DSP 102. Thus, the compression/decompression circuit compresses the image data in the internal memory 110 in JPEG or other predetermined formats. The compressed image data is recorded in the memory card 14 mounted to the memory card socket 112.

[0068] When a reproduction mode is selected by the mode selection switch 19, the image data is read from the memory card 14, and the read image data is decompressed by the compression/decompression circuit in the DSP 102, then reproduced and output on the liquid crystal monitor 18. It is also possible to transfer the image stored in the memory card 14 to the mobile phone 40, and send it to an outside by an e-mail sending function of the mobile phone 40.

[0069] The operations of the digital camera 10 thus configured will be described. FIG. 5 is a flowchart of a control procedure of the digital camera 10 of this embodiment. When the power supply switch 17 of the camera is operated to turn on the power supply (Step S510), the MPU 82 first determines whether the camera is in a power supply switching state (the state where the camera receives the power supplied from the mobile phone 40), based on the detected signal from the detection switch 66 (Step S512). When the power supply source is the battery 26 of the digital camera 10 (when determined NO), the process goes to Step S514, and all the power supply control switches SW11 to SW17 are turned on.

[0070] On the other hand, in Step S512, when determined that the camera receives the power supplied from the battery 42 of the mobile phone 40 (when determined YES), the process goes to Step S520. In Step S520, the power supply switch SW17 is turned on and other power supply switches SW11 to SW16 are OFF. Next, the voltage value (voltage a) of the battery 42 is read to determine whether the voltage a is below a determination reference value a1 previously defined (Step S522). The determination reference value a1 is defined as a voltage sufficient to operate the digital camera 10 by supplying power from the battery 42, and set as a lower limit voltage such that the voltage value decreases below the determination reference value a1 to cause irregular operation of the camera.

[0071] In Step S522, when determined that the voltage a is below the determination reference value a1 (when determined YES), the process goes to Step S524, and the frequency dividing ratio is lowered by one step, then the process returns to Step 522. Lowering the clock frequency dividing ratio by one step reduces power consumption to increase the voltage a.

[0072] In Step S522, when determined that the voltage a is above the determination reference value a1 (when determined NO), the process goes to Step S530. In step S530, it is determined whether the camera is set to the image-capturing mode. This determination is made based on a setting state of the mode selection switch 19. When the image-capturing mode is selected (when determined YES), the power supply switch SW 13 is turned on for allowing image-capturing (Step S532).

[0073] On the other hand, in Step S530, when determined NO (when the reproduction mode or other operation mode without image-capturing is selected), the power supply switch SW13 is turned off to control to prevent supplying power to the image pickup system circuit (Step S534). After Step S532 or Step S534, the process returns to Step S522. Then, operations of the operation keys are monitored to perform operations in accordance with operation instructions.

[0074] The digital camera 10 and the mobile phone 40 according to this embodiment are configured to share both batteries 26, 42, so that even if one battery is drained, power is supplied from the other battery to allow use of the device. This allows the device to be used for longer hours.

[0075] The above described power supply selection switches (SW1, SW2) are manually operated by users, but the power supply selection switches may be electronic switches that automatically control switching the power supplies. FIG. 6 shows a control procedure thereof.

[0076] After the power supply of the digital camera 10 is turned on (Step S610), the voltage of the battery 26 is input to an A/D conversion port of the MPU 82 and measured (Step S612). It is determined whether the measured voltage value is above the defined voltage (Step S614). If the voltage is above the defined voltage, there is no need to supply power from the outside, so that the power supply selection switch SW1 in the digital camera 10 remains set to A (Step S616).

[0077] On the other hand, when the voltage does not reach the defined voltage in Step S614, it is determined that power needs to be supplied from the outside, and the power supply selection switch SW1 is switched to B (Step S620). Then, a control signal indicating a switching state of the power supply (power supply switching control signal) is sent to the mobile phone 40 (Step S622) to enter a power saving operation mode (Step S624). At this time, the MPU 72 of the mobile phone 40 sets the power supply selection switch SW2 to D, and sets the mobile phone 40 to the power saving operation mode, based on the power supply switching control signal sent from the digital camera 10. Thus, the power is supplied from the battery 42 of the mobile phone 40 to the digital camera 10.

[0078] After Step S616 or Step S624, the process goes to Step S630. In Step S630, a timer counter is started, and when a count value reaches a defined value, the process returns to step S612. Thus, the above described switching determination processing of the power supply is repeated in a given cycle.

[0079] In FIG. 6, the controls of the digital camera 10 are described, but the same applies to the mobile phone 40. The MPU 72 of the mobile phone 40 monitors the voltage of the battery 42, and when determined that the battery 42 does not reach a defined voltage, the MPU 72 switches connection of the power supply selection switch 48 to C, and controls such that the mobile phone 40 receives the power supplied from the battery 26 of the digital camera 10. Then, the MPU 72 sends a control signal indicating a switching state of the power supply (power supply switching control signal) to the digital camera 10.

[0080] Next, a modification of the embodiment will be described. FIGS. 7 and 8 show circuits of essential portions according to another embodiment of the invention. In the drawings, identical or similar parts as in FIG. 2 are denoted by the same reference numerals, and descriptions thereof are omitted. In the embodiment shown in FIGS. 7 and 8, a connector 28 of a digital camera 10 is shared as a connecting unit of a remote control device 200.

[0081] As a device which automatically distinguishes between a state where a mobile phone 40 is connected to the digital camera 10 (FIG. 7) and a state where the remote control device 200 is connected to the digital camera 10 (FIG. 8), a detection pin PDk is provided in the connector 28. A detection signal line of the detection pin PDk connects to a Vcc output terminal of a DC/DC converter 58 via a pull-up resistance R2, and a detected signal is input to an internal circuit 56 of the digital camera 10.

[0082] A connector 44 of the mobile phone 40 is also provided with a detection pin PCk, and the detection pin PCk has no connection in the mobile phone 40 (non-connected terminal). Thus, when the digital camera 10 and the mobile phone 40 are connected via a connection cable 50 as shown in FIG. 7, the detected signal of the detection pin PDk becomes an “H (high)” signal.

[0083] On the other hand, a detection pin PRk provided in a connector 210 of the remote control device 200 shown in FIG. 8 connects to the ground in the remote control device 200. Thus, when the digital camera 10 and the remote control device 200 are connected via the connection cable 50, the detection pin PDk connects to the ground, and the detected signal becomes an “L (low)” signal.

[0084] The digital camera 10 determines that the remote control device 200 is connected thereto when the detected signal is “L”, while determines that the mobile phone 40 is connected thereto, or that there is no connection, when the detected signal is “H”. To distinguish between the connecting state and the non-connecting state of the mobile phone 40, a communication signal is output from the digital camera 10 to distinguish between them according to presence or absence of a reply.

[0085] A first pin PR1 of the connector 210 in the remote control device 200 connects to the ground (GND) together with the detection pin PRk. A second pin PR2 corresponds to a power input terminal, and connects to a DC/DC converter 212 in the remote control device 200. A third pin PR3 is a non-connected terminal. A fourth pin PR4 and the fifth pin PR5 connect to an internal circuit 214 and are used as data transfer lines.

[0086] A power supply voltage applied to the second pin PR2 is converted to a required voltage by the DC/DC converter 212 and then supplied to the internal circuit 214. When an operating unit 216 provided in the remote control device 200 is operated, a command signal in accordance with the operation is transferred to the digital camera 10 via the data transfer lines (fourth pin and fifth pin). The digital camera 10 operates in accordance with the command signal received from the remote control device 200. This achieves remote control of the digital camera 10 using the remote control device.

[0087] As described above, according to the invention, the digital camera connectable to the mobile electronic device can receive the power necessary to operate the camera from the battery of the external mobile electronic device to be connected, so that even if the battery of the digital camera is drained, switching to the battery of the electronic device allows the digital camera to be used for longer hours.

[0088] According to another aspect of the invention, the power can be supplied from the battery of the digital camera to the external mobile electronic device, so that even if the battery of the mobile electronic device is drained, switching to the battery of the digital camera allows the mobile electronic device to be used for longer hours.

[0089] It should be understood, however, that there is no intention to limit the invention to the specific forms disclosed, but on the contrary, the invention is to cover all modifications, alternate constructions and equivalents falling within the spirit and scope of the invention as expressed in the appended claims.

An electronic card is provided that is configured for removable insertion by a user in a digital image storage card slot of a digital camera. The electronic card includes a wireless telecommunications transmitter operative to transmit images taken using the camera for remote storage or display.

Digital Camera Claims

1. An electronic card configured for removable insertion by a user in a digital image storage card slot of a digital camera, wherein the electronic card includes a wireless telecommunications transmitter operative to transmit images taken using the camera for remote storage or display.

2. An electronic card according to claim 1, including a memory in which to store image data prior to transmission.

3. An electronic card according to claim 2, including a controller operative to control the memory and the transmitter so as to send the image data from the memory.

4. An electronic card according to claim 3, in which the controller is configured to control the memory and transmitter to send image data stored in the memory whenever a threshold in respect of the amount of image data stored in the memory is reached.

5. An electronic card according to claim 3, in which the controller is configured to control the memory and transmitter to send image data stored in the memory periodically.

6. An electronic card according to claim 3, in which the controller is configured to control the memory and transmitter to send image data stored in the memory upon receipt of an instruction signal to send provided by a control switch operable by the user.

7. A digital camera including a slot for removable insertion by the user of a digital image storage card, and an electronic card configured for removable insertion in said slot, the electronic card includes a wireless telecommunications transmitter operative to transmit images taken using the camera for remote storage or display.

8. A digital camera according to claim 7, in which the electronic card includes a memory in which to store image data prior to transmission.

9. A digital camera according to claim 8, including a controller operative to control the memory and the transmitter so as to send the image data from the memory.

10. A digital camera according to claim 9, in which the controller is configured to control the memory and transmitter to send image data stored in the memory upon receipt of an instruction signal to send provided by a control switch operable by the user.

11. A digital camera according to claim 10, in which the camera has a housing, the control button being mounted on the housing.

Digital Camera Description

FIELD OF THE INVENTION

[0001] The present invention relates to telecommunications, in particular to wireless telecommunications.

BACKGROUND OF THE INVENTION

[0002] It is known that digital cameras have largely superseded film cameras because they permit nearly immediate display and control of the picture taken. Digital cameras of known type include a relatively small amount of internal memory which is supplemented by a plug-in memory card of known type. Examples of known types of memory cards are Memory Sticks marketed by Sony Corporation, and CompactFlash cards. The plug-in memory card fits a corresponding slot in the camera. When the memory card becomes full, in order to be able to take more pictures the user of such known systems has only a limited number of choices. She has to replace the memory card, download the memory via a cable such as a USB cable to her personal computer, or delete some pictures.

SUMMARY OF THE INVENTION

[0003] The present invention avoids the disadvantageous situation of the prior art.

[0004] An embodiment of the present invention is an electronic card configured for removable insertion by a user in a digital image storage card slot of a digital camera. The electronic card includes a wireless telecommunications transmitter operative to transmit images taken using the camera for remote storage or display.

[0005] Another embodiment of the present invention is a digital camera including a slot for removable insertion by the user of a digital image storage card, and an electronic card configured for removable insertion in said slot. The electronic card includes a wireless telecommunications transmitter operative to transmit images taken using the camera for remote storage or display.

[0006] Embodiments of the present invention provide solutions to practical problems. Particularly with the trend to higher resolution pictures being taken, large numbers of conventional memory cards would otherwise be required. The problem is avoided of a user filling all the memory cards that she has whilst out and about, for example on a journey, so forcing her, if she wants to take any more pictures, to either delete pictures that she might otherwise wish to keep, or try to buy a further memory card. Also the pictures that are taken are more secure. For example if memory cards are lost, damaged or stolen, the transmitted pictures are not lost. This could be particularly valuable to users in dangerous areas.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Illustrative embodiments of the present invention will now be described by way of example and with reference to the drawings, in which:

[0008] FIG. 1 is a diagram illustrating features of the outward appearance of a digital camera and a digital image storage card according to one embodiment of the present invention,

[0009] FIG. 2 is a diagram illustrating the structure of the camera and card as shown in FIG. 1,

[0010] FIG. 3 is a diagram illustrating features of the outward appearance of a digital camera and a digital image storage card according to another embodiment of the present invention, and

[0011] FIG. 4 is a diagram illustrating the structure of the camera and card as shown in FIG. 3.

[0012] It should be noted that the drawings are not to scale but are schematic representations.

DETAILED DESCRIPTION

[0013] As shown in FIG. 1, a digital camera 2 with a plug-in electronic card 8 is provided. The camera 2 has a housing 4 and a lens 6. The camera 2 is provided with the plug-in electronic card 8 which is shaped and arranged so as to be removably insertable by the user in a corresponding slot 10 in the housing 4 of the camera 2. The slot had been designed for a plug-in memory card of known type. The electronic card 8 includes a wireless transceiver 12. The wireless transceiver 12 is a radio interface which operates in accordance with a Third Generation Partnership Project (3GPP) standard known as Universal Mobile Telecommunications System (UMTS). This standard is based on code division multiple access (CDMA). In alternative embodiments, the transceiver operates according to CDMA2000 or some other wireless telecommunications standard or methodology.

[0014] As shown in FIG. 2, the camera 2 includes an image capture stage 7 connected to the slot 10 via a controller 14. The controller 14 is operative to receive picture data from the image capture stage 7 and to pass image data data via the slot 10 to the electronic card 8. The card 8 includes an input interface 16 for picture data, and a local memory 20, the interface 16 being connected to the local memory 20. A card controller 18 acts to control storage in the local memory 20 of the picture data and control transmission of the picture data via the transceiver 12 by wireless transmission over a telecommunications network 16 to a remote station 22. In use, the transceiver 12 establishes a call connection with the remote station 22 via the network 16 so as to enable the picture data to be down-loaded thereto. Once picture data has been sent, that data is cleared from the local memory 12.

[0015] Electrical power is supplied to the electronic card 8 from a battery (not shown) in the camera 2 via electrical contacts (not shown) in the slot 10 and on the electronic card 8. In some other embodiments, the electronic card instead includes its own electrical power supply, such as a battery.

[0016] In this embodiment, the card controller 18 controls the wireless transceiver to automatically set up a call connection to the remote station after each picture is taken so as to send the picture data to the remote station 22.

[0017] In an alternative but otherwise similar embodiment, data of several pictures are stored in the local memory on the electronic card and sent upon a threshold in respect of amount of memory occupied being reached. For example, data is sent when, for example, the local memory is 90% full. This means the local memory does not becomes full that further pictures cannot be captured. In another alternative, picture data is sent to the remote station periodically, for example once a day.

[0018] As shown in FIGS. 3 and 4, in yet another alternative embodiment that is otherwise similar to the first embodiment described above, the electronic card 8′ includes a control button 24 which the user presses whenever she wants picture data to be sent to the remote station, activating the control button causes a signal to be sent to the card controller 18′ to which the card controller 18′ responds by instructing the local memory 20′ and wireless transceiver 12′ to send picture data.

[0019] In yet another alternative (not shown) the control button is located instead on the housing of the camera. The remote station can be any of a wide range of processors or display devices, for example a personal computer connected to the network by internet; the personal computer storing the picture data. Another option is that the remote station is a web server which provides storage of the user’s pictures, the pictures being accessed by a user station such as a personal computer functioning as a web browser. Yet another option is that the remote station is a computer station located in a photo-printing shop, the computer station acting to record the picture data as hard copy, in other words pictures on paper, or other recordings, such as compact disc read-only memories (CD-ROMs).

GENERAL

[0020] The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.

A system, method, and related computer program for storing digital camera data directly onto a detachable USB storage key in the digital camera. The present invention allows a user to store digital photographs taken with a digital camera directly onto the USB storage key and transfer said storage key and the data contained thereon to another computer controlled instrument, such as a PDA, camcorder, personal computer, or a second digital camera, without the use of a cable. The digital camera has a slot for operatively receiving a memory card for storage of digital photographs to be taken by said camera. The digital camera has a USB connection slot formed in the body of the camera adapted to receive a USB storage key. The USB key drive in the camera is accessible through said USB connection slot. A separatable USB storage key received in said USB connection slot and connected to said USB key drive stores data from said camera on the USB key. This invention allows a user more flexibility in storing digital photographs, and transferring stored data easily and quickly to another computer controlled instrument.

Digital Camera Claims

1. A computer controlled digital camera comprising: a camera body having formed therein a slot for operatively receiving a memory card for storage of digital photographs taken by said camera; a USB connection slot formed in said camera body adapted to receive a USB storage key; a USB key drive in said camera body accessible through said USB connection slot; and a separatable USB storage key insertable into said USB connection slot and connected to said USB key drive, whereby data from said camera is enabled to be stored on said USB key.

2. The computer controlled digital camera of claim 1 wherein the stored data on the USB key is transferable to a computer controlled instrument with a device driver for a USB key.

3. The computer controlled digital camera of claim 2 wherein the computer controlled instrument with a device driver for a USB key is a PDA.

4. The computer controlled digital camera of claim 2 wherein the computer controlled instrument with a device driver for a USB key is a camcorder.

5. The computer controlled digital camera of claim 2 wherein the computer controlled instrument with a device driver for a USB key is a personal computer.

6. The computer controlled digital camera of claim 2 wherein the computer controlled instrument with a device driver for a USB key is a second digital camera.

7. A method for storing data from a computer controlled digital camera, including the steps of: receiving a memory card for storage of digital photographs taken by a camera with a camera body having formed therein a slot for operatively receiving said memory card; receiving a USB storage key in a camera body having a USB connection slot formed in said camera body adapted to receive said key; accessing a USB key drive in said camera body through said USB connection slot; and receiving a separatable USB storage key in said USB connection slot and connected to said USB key drive, whereby data from said camera is enabled to be stored on said USB key.

8. The method of claim 7 wherein the stored data on the USB key is transferable to a computer controlled instrument with a device driver for a USB key.

9. The method of claim 8 wherein the computer controlled instrument with a device driver for a USB key is a PDA.

10. The method camera of claim 8 wherein the computer controlled instrument with a device driver for a USB key is a camcorder.

11. The method camera of claim 8 wherein the computer controlled instrument with a device driver for a USB key is a personal computer.

12. The method of claim 8 wherein the computer controlled instrument with a device driver for a USB key is a second digital camera.

13. A computer program having code recorded on a computer readable medium for storing data on a computer controlled digital camera, comprising: means in a camera body having formed therein a slot for operatively receiving a memory card for storage of digital photographs taken by said camera; means for a USB connection slot formed in said camera body adapted to receive a USB storage key; means for a USB key drive in said camera body accessible through said USB connection slot; and means for a separatable USB storage key insertable into said USB connection slot and connected to said USB key drive, whereby data from said camera is enabled to be stored on said USB key.

14. The computer program of claim 13 wherein the stored data on the USB key is transferable to a computer controlled instrument with a device driver for a USB key.

15. The computer program of claim 14 wherein the computer controlled instrument with a device driver for a USB key is a PDA.

16. The computer program of claim 14 wherein the computer controlled instrument with a device driver for a USB key is a camcorder.

17. The computer program of claim 14 wherein the computer controlled instrument with a device driver for a USB key is a personal computer.

18. The computer program of claim 14 wherein the computer controlled instrument with a device driver for a USB key is a second digital camera.

Digital Camera Description

TECHNICAL FIELD

[0001] The present invention relates to computer controlled consumer electronics devices or instruments, such as digital cameras, and specifically to the storage of digital pictures directly onto a USB storage key inserted into the USB connection slot in said camera. This invention also relates to the transfer of the stored data on the USB storage key to a computer controlled instrument, such as a PDA, camcorder, personal computer, or a second digital camera without the use of a cable.

BACKGROUND OF RELATED ART

[0002] The past decade has been marked by a technological revolution driven by the convergence of the data processing industry with the consumer electronics industry. The effect has, in turn, driven technologies that have been known and available but relatively quiescent over the years to now come into great demand in the marketplace.

[0003] The rapid expansion in the capacity of computers to perform support functions, the greater and greater miniaturization of computers, as well as reduction in costs to perform memory and computer operations has opened the door for computer controlled instrumentation. A key aspect of this expansion has been lower and lower cost memory. In recent years, this has been manifested in flash memory cards and sticks. At the current technology stage, these memory cards and sticks are detachably inserted into the computer controlled electronic instruments to provide an extra memory capacity of from one half to four to five gigabytes.

[0004] Memory cards use a flash memory that is based upon EEPROM (electrically erasable programmable read only memory) grid chips. Flash memory EEPROM works much faster than conventional EEPROM. Instead of erasing one byte at a time, it erases an entire block or an entire chip at a time and then rewrites. Smartmedia and Compactflash provide the “electronic film” for digital cameras while the Sony memory stick is quite popular in digital cameras and for computer controlled video games. These high capacity memory cards and sticks have been performing hard drive storage functions for the above-described computer controlled electronic instruments. In this connection, the SSFDC (solid state floppy disc card) developed by Toshiba, Inc. may function as the above-described Smartmedia card. Similarly, the above CompactFlash is a small circuit board with at least one flash memory chip and a dedicated controller chip encased in a housing or shell.

[0005] With this rapid expansion of the use of detachable memory cards for an increasing variety of computer controlled electronic instruments, the cards themselves are becoming relatively ubiquitous. The memory cards may be in or on the desks and cabinets of their users. The current use of memory cards requires the attachment of a USB cable between the camera and the personal computer or other computer controlled instrument, or that the personal computer or other computer controlled instrument be equipped with a media reader that can handle the specific types of storage the camera uses.

[0006] The present invention involves the Universal Serial Bus (USB), which was originally developed in 1995 by Intel, Compaq, DEC, IBM, Microsoft, NEC, and Northern Telecom, to define an external expansion bus that simplified adding peripherals to a PC with low cost to the user. The USB, version 1.1, has a data transfer rate of 12 megabits per second (Mbps) for connecting peripherals to a microcomputer. USB can connect up to 127 peripherals, such as external CD-ROM drives, printers, modems, mice, and keyboards to the system through a single, general purpose port, which is accomplished by daisy chaining peripherals together. USB is designed to add such devices without having to shut down and restart the system. Currently, USB enjoys tremendous success in the marketplace, and most peripheral vendors are developing products to this specification. Virtually all new PCs have one or more USB ports included thereon. USB, version 2.0, offers its users an additional range of higher performance peripherals, such as video-conferencing cameras, and increases data throughput by a factor of 40, since it has a higher bandwidth. USB 2.0 has 480 Mbps bandwidth.

[0007] To better understand USB, an understanding of the roles of each of its major elements is necessary, which is described in greater detail in the article “Understanding Universal Serial Bus Part 1: USB Basics”, Embedded Systems Programming, John Canosa, Miller Freeman, San Francisco, Calif., USA, June 1997. These major elements are the host PC hardware and software, the hub, and the peripheral. The role of the system software is to provide a uniform view of I/O systems for all applications software. The system software hides hardware implementation details causing the application software to be more portable. For the USB I/O subsystem, the system software manages the dynamic attach and detach of peripherals. This phase is called enumeration, and involves communicating with the peripheral to discover the identity of a device driver that should be loaded if it has not been loaded yet. A unique address is assigned to each peripheral during enumeration to be used for run-time data transfers. During run-time, the host PC initiates transactions to specific peripherals, and each peripheral accepts its transactions and responds accordingly. The host PC software incorporates the peripheral into the system power management scheme and can manage overall system power without user interaction.

[0008] The role of the hub is to provide managed power to attached peripherals, in addition to its obvious role of providing additional connectivity for USB peripherals. The hub recognizes dynamic attachment of a peripheral and provides at least 0.5 W of power per peripheral during initialization. Under control of the host PC software, the hub may provide more device power, up to a maximum of 2.5 W, for peripheral operation. A newly attached hub will be assigned its unique address, and hubs may be cascaded up to five levels deep. During run-time, a hub operates as a bi-directional repeater and will repeat USB signals as required on upstream (towards the host) and downstream (towards the device) cables. The hub also monitors these signals and handles transactions addressed to itself. All other transactions are repeated to attached devices. A hub supports both 12 Mbps (full-speed) and 1.5 Mbps (low-speed) peripherals.

[0009] All USB peripherals must react to request transactions sent from the host PC. The peripheral responds to control request transactions sent from the host PC. The peripheral responds to control transactions that, for example, request detailed information about the device and its configuration. The peripheral sends and receives data to/from the host using a standard USB data format. This standardized data movement to/from the PC host and interpretation by the peripheral gives USB its enormous flexibility with little PC host software changes. USB peripherals can operate at 12 Mbps or 1.5 Mbps. Presently, computer systems and cameras sold in the marketplace include integrated USB ports as a general feature.

SUMMARY OF THE PRESENT INVENTION

[0010] The present invention provides a solution to the problems related to the inflexibility or inconvenience of storing digital photographs and transferring said stored data to another computer controlled instrument. Accordingly, the present invention provides a digital camera having a USB key drive, wherein the digital camera has a slot for operatively receiving a memory card for storage of digital photographs taken by said camera. The digital camera also has a USB connection slot formed in the body of the camera adapted to receive a USB storage key. It should be understood that in order to practice the present invention, the camera manufacturers would have to build a USB port into the camera, provide an adapter for use, or manufacture a USB memory key with a non-standard plug end to fit a current camera’s port. A typical port is illustrated on FIG. 1. This port has been simplified for purposes of illustration. In reality, most cameras are equipped with a USB port that allows interface with smaller and differently shaped ports or connection slots other than would fit a standard USB cable plug. Most cameras currently are accessorized with a cord that has one standard plug end, and one non-standard plug end. The USB key drive in the camera is accessible through said USB connection slot. A separatable USB storage key is received in said USB connection slot and connected to said USB key drive, whereby data from said camera is able to be stored directly on the USB key.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The present invention will be better understood and its numerous objects and advantages will become more apparent to those skilled in the art by reference to the following drawings, in conjunction with the accompanying specification, in which:

[0012] FIG. 1 is a diagrammatic illustration of a USB key drive in accordance with the present invention capable of being inserted into a computer controlled electronic instrument, i.e. a digital camera;

[0013] FIG. 2 is a diagrammatic illustration of a USB storage key in accordance with the present invention being inserted into a computer controlled electronic instrument, i.e. a digital camera;

[0014] FIG. 3 is a block diagram of a simplified control circuitry on controller integrated circuitry on an IC chip on a USB key drive in accordance with this invention;

[0015] FIG. 4 is an illustrative flowchart in accordance with this invention showing how the USB key drive stores digital photographs directly thereon; and

[0016] FIG. 5 is a flowchart of an illustrative run of the process set up in FIG. 4.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0017] Referring to FIG. 1, a typical use of the USB key drive of the present invention in connection with a computer controlled instrument, e.g. a digital camera, is shown. The camera 16 has a slot 17 into which a typical memory card 13 may be removably inserted to operatively engage the computer system in the camera to function as a typical extended memory card, and will be hereinafter described in greater detail. The digital camera 16 also has a USB connection slot 18 adapted to receive a USB storage key 19. It should be understood that in order to practice the present invention, the camera manufacturers would have to build a USB port into the camera, provide an adapter for use, or manufacture a USB memory key with a non-standard plug end to fit a current camera’s port. USB connection slot 18 or port has been simplified for purposes of illustration. In reality, most cameras are equipped with a USB port that allows interface with smaller and differently shaped connection slots or ports other than would fit a standard USB cable plug. Most cameras currently are accessorized with a cord that has one standard plug end, and one non-standard plug end. Of course, the operations to be described will be applicable to an extended memory card and computer controlled instrument co-action.

[0018] FIG. 2 shows the digital camera 16, wherein the USB storage key 19 is inserted into the USB connection slot 18, and can receive data from the digital camera 16 and store said data on the USB storage key 19. The USB storage key 19 and the data stored thereon can be transferred from the digital camera 16 to any USB capable computer controlled instrument without first downloading data to a PC or other computer system. The user can detach the USB storage key 19 and load the data onto any computer system with a USB port without the use of a cable.

[0019] FIG. 3 is a block diagram of simplified control circuitry on controller integrated circuitry on an IC chip of a memory card 13, and the storage of data onto a USB storage key and the transfer of said stored data to a computer controlled instrument in accordance with this invention. In order to better understand the present invention, an understanding of the memory card is necessary. The controller chips provide specific purpose logic to control the access, reading and writing into the flash memory array chips. These logic or control chips contain data processors 20, operating systems stored in RAM 22 and a permanent programmable memory, and a programmable ROM 21 that may be EEPROM, e.g. flash EEPROM. All of the routines and programs may also be conventionally stored in this flash EEPROM 21. These include memory card operating systems and built-in applications that may also be conventionally stored in the RAM. The digital camera with a USB key contains a system bus 23 connected via I/O output at one end to the conventional connectors of the camera 16 to the computer controlled instrument. In accordance with the present invention, this relatively standard structure is modified to have an appropriate connection via bus 24 to a USB key drive 25, and a USB connection slot 28 for a USB storage key is present. A separable USB storage key 26 is received in said USB connection slot 28 to said USB key drive 25, whereby data from said camera 16 is enable to be stored on said USB key 26. The indicators are controlled through the controller processor 20 in accordance with the routines illustrated in FIG. 4 and FIG. 5, to be subsequently described.

[0020] There is also shown a bus branch to a power supply. Where the USB storage key is functioning already operatively inserted into the computer controlled instrument, the power supply of the instrument itself may be used for this function. By use of the present invention, the user is able to transfer stored data from a digital camera to a computer controlled instrument, e.g. a laptop computer, camcorder, personal computer, or a second digital camera.

[0021] The running of the process set up in FIG. 3 will now be described with respect to the flowchart of FIG. 4. The flowchart represents some steps in a routine that will illustrate the operation of the invention. A determination is made as to whether the user wants to store digital photographs on a traditional memory card, step 51. If Yes, the application nodes are written to, step 52. A memory card stores digital photographs taken by said digital camera, step 53. If No, a determination is made as to whether the user wants to store digital photographs on a USB storage key, step 54. If No, the process ends. If Yes, a USB storage key is inserted into a USB connection slot, step 55. The USB storage key stores data from said camera thereon, step 56. Then a determination is made as to whether the stored data on the USB storage key is to be transferred to a computer controlled instrument, step 57. If Yes, the USB storage key is detached from the digital camera, step 58. Then the USB storage key is inserted into a USB port of a computer controlled instrument, step 59, and the stored data is accessible to said computer controlled instrument. If No, the data remains stored on the USB storage key in the digital camera, step 60.

[0022] Referring now to FIG. 5, an illustrative flowchart in accordance with this invention showing how the USB storage key stores data from a digital camera directly thereon, and transfers said stored data to a computer controlled instrument without the use of a cable. Means provided in a digital camera body having formed therein a slot for operatively receiving a memory card for storage of digital photographs taken by said camera, step 70. Receiving means in said camera’s USB connection slot adapted to receive a USB storage key, step 71. Means provided in said camera body for accessing a USB key drive through said USB connection slot, step 72. Means provided in said USB connection slot for receiving a separatable USB storage key, and connected to said USB key drive, whereby data from said camera is enabled to be stored on said USB key, step 73. Means for removing said USB storage key from a digital camera, and transferring the USB storage key and its stored data to a computer controlled instrument, such as a PDA, personal computer, camcorder, or a second digital camera, without the use of a cable, step 74.

[0023] Although certain preferred embodiments have been shown and described, it will be understood that many changes and modifications may be made therein without departing from the scope and intent of the appended claims.

A digital camera is provided with a plurality of group specifying keys for specifying a use purpose of a photographed picture. In an external flash memory of the digital camera that stores the photographed pictures, a plurality of index files that correspond to the group specifying keys are generated. When any one of the plurality of group specifying keys is pressed when at least one of the recorded pictures are displayed, file names of those displayed pictures are sequentially entered in an index file corresponding to that pressed group specifying key. When using the picture file, a personal computer reads out a plurality of picture files described in an index file corresponding to a desired use purpose to then conduct the corresponding processes based on that index file.

Digital Camera Claims

1. An image data managing apparatus comprising: a first selecting section for selecting via a manual operation a desired index file from a plurality of index files which are stored in an index file storage section, each of said index files containing at least one identifier which respectively identifies an image data piece; and a control section for executing image processing on at least one image data piece among image data pieces stored in an image storage section, said at least one image data piece being identified by the identifier contained in the desired index file selected by the first selecting section via the manual operation.

2. The image data managing apparatus according to claim 1, wherein the index file storage section and the image storage section are provided on a recording medium which is removably provided in a main body of a digital camera.

3. The image data managing apparatus according to claim 1, wherein the index file storage section and the image storage section are provided in a digital camera, which further comprises a first receiving section for receiving the plurality of index files stored in the index file storage section in the digital camera; and wherein: said first selecting section selects the desired index file from the plurality of index files received by the first receiving section; said control section comprises: (i) an output section for outputting to the digital camera a transfer request signal for requesting transfer of the at least one image data piece identified by the identifier contained in the selected index file, and (ii) a second receiving section for receiving from the digital camera the image data piece requested to be transferred by the transfer request signal output from the output section; and said control section executes image processing on the image data piece received by the second receiving section.

4. The image data managing apparatus according to claim 1, further comprising a display section for displaying the plurality of index files stored in the index file storage section, wherein the first selecting section selects the desired index file from the plurality of index files displayed by the display section.

5. The image data managing apparatus according to claim 1, further comprising a second selecting section for selecting via a manual operation a desired image processing from a plurality of kinds of image processing, wherein the control section executes the image processing selected by the second selecting section on the image data piece identified by the identifier contained in the selected index file.

6. The image data managing apparatus according to claim 1, wherein: the index file storage section stores a plurality of kinds of index files; and said control section executes image processing determined based on a kind of the selected index file on the image data piece identified by the identifier contained in the selected index file.

7. An image data managing apparatus comprising: first selecting means for selecting via a manual operation a desired index file from a plurality of index files which are stored in an index file storage section, each of said index files containing at least one identifier which respectively identifies an image data piece; and control means for executing image processing on at least one image data piece among image data pieces stored in an image storage section, said at least one image data piece being identified by the identifier contained in the desired index file selected by the first selecting means via the manual operation.

8. A computer-readable recording medium having recorded thereon an image data managing program that is executable by a computer of an image data managing apparatus for processing image data to cause the computer to execute: selecting, via a manual operation, a desired index file from a plurality of index files which are stored in an index file storage section, each of said index files containing at least one identifier which respectively identifies an image data piece; and executing image processing on at least one image data piece among image data pieces stored in an image storage section, said at least one image data piece being identified by the identifier contained in the desired index file selected via the manual operation.

9. An image data managing method comprising: selecting, via a manual operation, a desired index file from a plurality of index files which are stored in an index file storage section, each of said index files containing at least one identifier which respectively identifies an image data piece; and executing image processing on at least one image data piece among image data pieces stored in an image storage section, said at least one image data piece being identified by the identifier contained in the desired index file selected via the manual operation.

10. An image data managing apparatus comprising: a selecting section for selecting via a manual operation a desired kind of image processing from a plurality of kinds of image processing as a kind of image processing for an index file, said index file being stored in an index file storage section and containing identifiers which respectively identify image data pieces; and a control section for executing the kind of image processing selected by the selecting section on identified image data pieces among image data pieces stored in an image storage section, said identified image data pieces being identified by the identifiers contained in the index file stored in the index file storage section.

11. The image data managing apparatus according to claim 10, further comprising a display section for displaying contents of the plurality of kinds of image processing, wherein the selecting section selects the contents of the desired kind of image processing via the manual operation from the contents of the plurality of kinds of image processing which are displayed by the display section.

12. The image data managing apparatus according to claim 10, wherein the index file storage section and the image storage section are formed on a recording medium which is removably provided in a main body of a digital camera.

13. The image data managing apparatus according to claim 10, wherein the index file storage section and the image storage section are provided in a digital camera, which further comprises a first receiving section for receiving the index file stored in the index file storage section in the digital camera; and wherein: said control section comprises: (i) an output section for outputting to the digital camera a transfer request signal for requesting transfer of the image data pieces identified by the identifiers contained in the index file received by the first receiving section, and (ii) a second receiving section for receiving from the digital camera the image data pieces requested to be transferred by the transfer request signal output from the output section; and said control section executes the selected kind of image processing on the image data pieces received by the second receiving section.

14. The image data managing apparatus according to claim 10, wherein the plurality of kinds of image processing comprises copy processing, display processing and print processing.

15. An image data managing apparatus comprising: selecting means for selecting via a manual operation a desired kind of image processing from a plurality of kinds of image processing as a kind of image processing for an index file, said index file being stored in an index file storage section and containing identifiers which respectively identify image data pieces; and control means for executing the kind of image processing selected by the selecting means on identified image data pieces among image data pieces stored in an image storage section, said identified image data pieces being identified by the identifiers contained in the index file stored in the index file storage section.

16. A computer-readable recording medium having recorded thereon an image data managing program that is executable by a computer of an image data managing apparatus for processing image data to cause the computer to execute: selecting, via a manual operation, a desired kind of image processing from a plurality of kinds of image processing as a kind of image processing for an index file, said index file being stored in an index file storage section and containing identifiers which respectively identify image data pieces; and executing the selected kind of image processing on identified image data pieces among image data pieces stored in an image storage section, said identified image data pieces being identified by the identifiers contained in the index file stored in the index file storage section.

17. An image data managing method comprising: selecting, via a manual operation, a desired kind of image processing from a plurality of kinds of image processing as a kind of image processing for an index file, said index file being stored in an index file storage section and containing identifiers which respectively identify image data pieces; and executing the selected kind of image processing on identified image data pieces among image data pieces stored in an image storage section, said identified image data pieces being identified by the identifiers contained in the index file stored in the index file storage section.

Digital Camera Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application is a Divisional of U.S. Application Ser. No. 10/014,090 filed Nov. 13, 2001, which is based upon and claims the benefit of priority from the prior Japanese Patent No. 2000-350407, filed Nov. 17, 2000, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a digital camera capable of outputting picture (image) data to an external apparatus, a picture data managing device, a picture data managing method, and a recording medium in which a picture data managing program is recorded.

[0004] 2. Description of the Related Art

[0005] Recently, digital cameras have been equipped with a display such as an LCD, which functions as a view finder, and which allows a photographed picture to be reproduced and confirmed on the display without using any other devices. In such a digital camera, a picture of a subject imaged by a solid imaging device such as a CCD is recorded as picture data in a recording medium such as a flash memory. Pieces of the picture data are compressed in a predetermined format such as JPEG (Joint Photographic Expert Group) and are then recorded in an order they were photographed in the recording medium as picture files having file names each consisting of, for example, a date and time.

[0006] Furthermore, some digital cameras typically utilize cable communication, for example via a USB (Universal Serial Bus) connection, or wireless communication, for example via infrared light, to thereby transmit picture data to an external apparatus such as another digital cameras or a personal computer. Digital cameras may also have a detachable memory such as the above-mentioned recording medium, which may be attached to the external apparatus so that the external apparatus can access the picture data. Therefore, with such a digital camera, the picture data recorded by photographing can be accessed on a personal computer and copied on a floppy disk, for example, so that the pictures may be distributed to a plurality of persons. That is, it is possible to make extra copies of photographed images, as is possible with silver-salt cameras.

[0007] However, in an attempt to copy specific picture data to a floppy disk with a personal computer, it is difficult to identify the picture to be copied using only the above-mentioned file name. Accordingly, it is necessary to display and confirm on a monitor the pictures in the order (or reverse order) they were photographed and then to select a specific one of them and copy it on a floppy disk. It is thus troublesome and inefficient to distribute many pictures to many persons. In particular, when a personal computer with a low picture processing capability is used, it takes a long time to confirm the pictures to be copied, thus causing the process of copying and distributing the pictures to be remarkably inefficient.

BRIEF SUMMARY OF THE INVENTION

[0008] It is an object of the present invention to provide a digital camera, a picture data managing apparatus, a picture data managing method, and a recording medium recording therein a picture data managing program that can output picture data recorded in the digital camera to an external apparatus and improve a working efficiency in picture processing executed by the external apparatus on the picture data.

[0009] To achieve the above object, according to a first preferred aspect of the present invention a digital camera is provided which includes: an imaging section for imaging a subject and outputting a plurality of pieces of image data; a specifying section for specifying at least one of the plurality of image data pieces output from the imaging section; an index file generating section for generating an index file containing an identifier with which any image data piece specified by the specifying section can be identified; and a control section for storing in an image storage section a plurality of image data pieces output from the imaging section, and for storing in an index file storage section an index file generated by the index file generating section, wherein the configuration enables improving a working efficiency in image processing on the image data by an external apparatus.

[0010] According to a second preferred aspect of the present invention a digital camera is provided which includes: imaging means for imaging a subject and outputting a plurality of pieces of image data; specifying means for specifying at least one of a plurality of image data pieces output from the imaging means; index file generating means for generating an index file containing an identifier with which any image data piece specified by the specifying means can be identified; and control means for storing in an image storage section the plurality of image data pieces output from the imaging means and also storing in an index file storage section an index file generated by the index file generating means, wherein the configuration enables improving a working efficiency in image processing on the image data by an external apparatus.

[0011] According to a third preferred aspect of the present invention an image data managing apparatus is provided which includes: an image storage section for storing a plurality of image data pieces; a specifying section for specifying at least one of the plurality of image data pieces stored in the image storage section; an index file generating section for generating an index file containing an identifier with which any image data piece specified by the specifying section can be identified; and an index file storage section for storing an index file generated by the index file generating section, wherein the configuration enables improving a working efficiency in image processing on the image data by an external apparatus.

[0012] According to a fourth preferred aspect of the present invention a computer-readable recording medium is provided that has recorded thereon an image data managing program for causing a computer of a digital camera provided with an imaging section for imaging a subject and outputting picture data thereof to execute the processes of: specifying at least one of a plurality of pieces of image data output from the imaging section; generating an index file containing an identifier with which any specified image data piece can be identified; and storing a generated index file in a memory, whereby a working efficiency in image processing on the image data by an external apparatus can be improved.

[0013] According to a fifth preferred aspect of the present invention an image data managing method for a digital camera is provided which includes: imaging a subject and outputting image data; specifying at least one of a plurality of thus output image data pieces; generating an index file containing an identifier with which any specified image data piece can be identified; and storing a generated index file in a memory, whereby a working efficiency in image processing on the image data by an external apparatus can be improved.

[0014] According to a sixth preferred aspect of the present invention an image data managing apparatus is provided which includes: an acquiring section for acquiring an index file which is stored in an index file storage section and which contains an identifier with which any image data piece can be identified; and a control section for executing image processing on any one of the image data pieces stored in an image storage section that is identified by the identifier contained in an index file acquired by the acquiring section, wherein the configuration enables improving a working efficiency in image processing on the image data by an external apparatus.

[0015] According to a seventh preferred aspect of the present invention an image data managing apparatus is provided which includes: acquiring means for acquiring an index file which is stored in an index file storage section and which contains an identifier with which any image data piece can be identified; and control means for executing predetermined image processing on any one of the image data pieces stored in an image storage section that is identified by an identifier contained in an index file acquired by the acquiring means, wherein the configuration enables improving a working efficiency in image processing on the image data by an external apparatus.

[0016] According to an eighth preferred aspect of the present invention a computer-readable recording medium is provided that has recorded thereon an image data managing program for executing the processes of: acquiring an index file which is stored in an index file storage section and which contains an identifier with which any image data piece can be identified into a computer of an image data managing apparatus for processing image data; and executing predetermined image processing on any one of image data pieces stored in an image storage section that is identified by an identifier contained in an acquired index file, whereby a working efficiency in image processing on the image data by an external apparatus can be improved.

[0017] According to a ninth preferred aspect of the present invention a picture data managing method is provided which includes: acquiring an index file which is stored in an index file storage section and which contains an identifier with which any image data piece can be identified; and executing predetermined image processing on any one of the image data pieces stored in an image storage section that is identified by an identifier contained in an acquired index file, whereby a working efficiency in image processing on the image data by an external apparatus can be improved.

[0018] Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0019] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention.

[0020] FIG. 1 is an external view for showing a digital camera related to a first embodiment of the present invention;

[0021] FIG. 2 is a block diagram for showing an outline of the digital camera of the first embodiment;

[0022] FIG. 3 is an illustration for showing a file storage construction in an external flash memory of the first embodiment;

[0023] FIG. 4 is an illustration for explaining data contents of an index file recorded in the external flash memory;

[0024] FIG. 5 is a block diagram for showing an outline of a personal computer related to the first embodiment;

[0025] FIG. 6 is a flowchart for showing an operation of grouping pictures photographed by the digital camera of the first embodiment;

[0026] FIG. 7 is a flowchart for showing an operation of picture processing by the personal computer of the first embodiment;

[0027] FIG. 8 is a flowchart for showing another operation of picture processing by the personal computer of the first embodiment;

[0028] FIG. 9 is a flowchart for showing a further operation of picture processing by the personal computer of the first embodiment;

[0029] FIG. 10 is a flowchart for showing a still further operation of picture processing by the personal computer of the first embodiment;

[0030] FIG. 11 is a block diagram for showing an outline of a digital camera related to a second embodiment of the present invention;

[0031] FIG. 12 is a flowchart for showing an operation of the side of the digital camera of the second embodiment; and

[0032] FIG. 13 is a flowchart for showing an operation of the side of a personal computer of the second embodiment.

DETAILED DESCRIPTION OF THE INVENTION

[0033] The following will describe embodiments of the present invention with reference to the drawings.

[0034] First Embodiment

[0035] FIG. 1 is an external view for showing a digital camera 1 related to the first embodiment of the present invention. A digital camera 1 includes a camera section 3 coupled to a side of an apparatus body 2 in such a manner that the camera section 3 may rotate in a vertical direction. The camera section 3 is equipped with an optical system including an imaging lens, a diaphragm, etc., which are not shown. A shutter key 4 is provide on the right side of the apparatus body 2. On the rear face of the apparatus body 2, a display 5, i.e. a TFT-type LCD monitor, is provided. On a side of the display 5, a mode switching key 6 is provided for switching the operation mode of the digital camera 1 between an imaging mode (REC) for imaging and recording an image of a subject and a reproduction mode (PLAY) for displaying a recorded picture. Below the display 5, first through fourth operation keys 7a-7d (shown as “A-KEY”, “B-KEY”, C-KEY”, and “D-KEY”) are arranged in this order from the left. The first through fourth operations keys of 7a-7d are assigned different functions in the different imaging and reproduction modes; in the reproduction mode, for example, they are used as a group specification key, thus functioning as a specifying section (specifying means) of the present invention.

[0036] FIG. 2 is a block diagram for showing an outlined electrical configuration of the digital camera 1. The digital camera 1 is housed in the camera section 3 and includes a CCD 11, on whose light-reception face is formed an optical image, and a DSP/CPU 12. The DSP/CPU 12 is a one-chip micro-controller having a function of sampling, amplifying, and digitizing an analog signal and a function of controlling various sections of the digital camera 1.

[0037] To the DSP/CPU 12 is connected a TG (Timing Generator) 13 for driving the CCD 11. A unit circuit 14, to which an imaging analog signal corresponding to a brightness of a subject output from the CCD 11 is input, is connected to TG 13. The unit circuit 14 is comprised of a CDS for holding an imaging analog signal output from the CCD 11, a gain-control amplifier (AGC) which is an analog amplifier for amplifying this imaging signal, and an A/D converter (AD) for converting an imaging signal amplified at the gain adjustment amplifier into an imaging digital signal, in such a configuration that an output signal of the CCD 11 is sent as a digital signal to the DSP/CPU 12 via the unit circuit 14.

[0038] The above-mentioned display 5, a key-input section 15 for generating a key-input signal corresponding to any of the above-mentioned shutter key, the plurality of operation keys 7a-7d, and a power supply key, and a timer section 16 having a calendar function and a function to output the current date data, day-of-the-week data, and time data to the DSP/CPU 12 are connected to the DSP/CPU 12. And a DRAM 18, an internal flash memory 19, and an external flash memory 20 are connected to the DSP/CPU 12 via an address/data bus 17. The DRAM 18 temporarily stores a digitized imaging signal of a subject imaged by the CCD 11 when the system is set in the photographing wait mode. The built-in flash memory 19 serves as a recording medium of the present invention for storing a variety of kinds of data used for control of an operating program of the DSP/CPU 12 and the various sections, and the built-in flash memory 19 also has a reserved work area that is used by the DSP/CPU 12. The DSP/CPU 12 operates according to the above-mentioned operating program to function as a control section (control means), a specifying section (specifying means), and an index file generating section (index file generating means) of the present invention.

[0039] The external flash memory 20 functions as a picture storage section and an index file storage section of the present invention and serves as a card-type recording medium which can be attached to and detached from the apparatus body 2, so that when photographing is instructed by pressing the shutter key 4 in the photographing wait mode, one frame of picture data read out by the DSP/CPU 12 from the DRAM 18 undergoes various picture processes and is compressed and finally recorded as a picture file in this external flash memory 20.

[0040] FIG. 3 shows a storage construction of a picture file in the external flash memory 20. In this embodiment, when photographing is instructed, a JPEG-format picture file is generated, so that as shown in FIG. 3, in the external flash memory 20, following a DCIM folder 20a provided beforehand in the initial state thereof are dated folders 20b (”0101″, “0102″, ) having a photographing date. These dated folder 20b are followed by sequentially recorded picture files 20c of pictures photographed on the same day that have file names (”0101001.jpg”, “0101002.jpg”, ) each consisting of a date and a serial number.

[0041] Each dated folder 20b is followed by the picture file 20c as well as recorded index files 20d (”folderA.text”, “folderB.text”, “folderC.text”) created for each of a plurality of groups predefined by the user. As shown in FIG. 4, the index files 20d are a text-format file consisting only of character data with a described file name of one or a plurality of picture files 20c in each dated folder 20b, and the index files 20d correspond to the first through fourth operation keys 7a to 7d, respectively.

[0042] In the imaging wait state where the shutter key 4 is not pressed in the above-mentioned imaging mode, the display 5 functions as a view finder by displaying as a through picture a subject image taken in from the CCD11 and, in the above-mentioned reproduction mode, the display 5 displays a list of pictures as downsized that were recorded in the external flash memory 20 or displays a user-selected picture in a size set at the time of photographing.

[0043] FIG. 5 is a block diagram for showing a personal computer as the external apparatus used together with the digital camera 1 in this embodiment. The personal computer 30 has a CPU 31, a ROM 32 and a RAM 33 which are connected to the CPU 31, a CRT driving circuit 35 for driving a CRT 34, and a printer 42. A keyboard 37, a mouse 38, a hard disk drive 39, a floppy disk drive 40, and a card reader 41, which has a slot through which an external flash memory 20 used in the digital camera 1 is removably insertable, are connected to the CPU 31 through an interface 36. A program for enabling the card reader 41 to be used, a predetermined copying program for copying, into a drive specified by a user, a predetermined picture file recorded in the external flash memory 20 mounted to the card reader 41, and a predetermined application program for reading picture data from and writing data to the external flash memory 20 are all installed in the hard disk drive 39.

[0044] (Grouping of Pictures in Digital Camera)

[0045] The following will describe an operation of grouping pictures in the above-mentioned digital camera 1 in the reproduction mode with reference to the flowchart of FIG. 6. This flowchart shows the behavior of subroutines called by a main routine (not shown) and sequentially executed.

[0046] When the reproduction mode is set and any one of the pictures stored in the external flash memory 20 is shown on the display 5 (or a plurality of downsized pictures are shown on the display 5), if any one of the above-mentioned group specifying keys (first through fourth operation keys) 7a to 7d is pressed (YES is answered at step SA1), the digital camera 1 decides whether an index file 20d which corresponds to the pressed group specifying key is present following a dated folder 20b in which a picture file 20c of the picture displayed (or selected) is present (step SA2). When such a corresponding index file 20d is present (YES is answered at step SA2), for example, “folderA.text” is read out as that corresponding index file 20d if that pressed group specifying key is the first operation key 7a (step SA3). If no corresponding index file 20d is present (NO is answered at step SA2), an index file 20d corresponding to the pressed group specifying key, for example, “folderD.text” is newly created if that pressed group specifying key is the fourth operation key 7d (step SA4).

[0047] Subsequently, the process enters a file name (e.g., “0101005.jpg”) of the currently displayed or selected picture in the index file 20d read out at step SA3 or created at step SA4 then updates (saves) this index file 20d (step SA5) and then returns to the main routine in the reproduction mode. By repeating these operations, the pictures recorded in the external flash memory 20 are sorted into a plurality of groups (four groups in this embodiment), which are indicated by index files 20d. Note here that the user can specify the same picture over a plurality of groups, in which case, the same file name is entered in a plurality of different index files 20d.

[0048] (Copying Pictures in Personal Computer)

[0049] The following will describe the operations when the user has activated the above-mentioned copying program in a state where the external flash memory 20 after undergoing the above-mentioned processing by the digital camera 1 is mounted to the card reader 41, with reference to the flowchart of FIG. 7.

[0050] When the copying program is activated, the personal computer 30 displays on the CRT 34 a screen requesting the location (other than the card reader 41) to which a picture file is to be copied, e.g. the floppy disk drive 40 etc. (step SB1), and then awaits specification of the recording medium (step SB2). If the user then specifies a recording medium (drive) (YES is answered at step SB2), the index files 20d present following all the dated folders 20b in the external flash memory 20 are retrieved and listed on the CRT 34 (step SB3) and then specification of at least one of the index files 20d is awaited (step SB4).

[0051] If, subsequently, one or more of the index files 20d (e.g., “folderA.text”) is specified from among this list displayed on the CRT 34 (YES is answered at step SB4), all the specified index files 20d are read out (step SB5). Then, all the picture files described in the one or more index files 20d having the same file name are sequentially read out from the external flash memory 20 and the read out picture files 20c are copied to a recording medium (drive) specified by the user at step SB1 (step SB6). When the relevant picture files 20c are all copied completely (YES is answered at step SB7), the process ends immediately.

[0052] In this embodiment, therefore, the user can perform the following steps to distribute one or a plurality of pictures photographed by the digital camera 1 using a floppy disk. First, for example, he predefines the first operation key 7a (”A-KEY”) of the digital camera 1 as a group specifying key for specifying a picture to be copied so that the digital camera 1 may sequentially display or select pictures to be distributed and, when the first operation key 7a is pressed a picture is selected to be copied. Next, the external flash memory 20 is detached from the digital camera 1 and attached to the personal computer 30 to supply the index file 20d (”folderA.text”) which corresponds to the first operation key 7a (”A-KEY”) to the personal computer 30 so that the one or more pictures specified therein may be copied to a floppy disk. Thus, one or a plurality of pictures to be automatically copied to the floppy disk at a time.

[0053] That is, the user can operate the personal computer to copy any pictures recorded in the external flash memory 20 directly to the floppy disk without a need of displaying and confirming them one by one. This feature enables rapid copying even with a personal computer having a low picture processing capability. Moreover, even many pictures to be distributed can be copied to the floppy disk at a time. The picture files, therefore, can be copied easily and efficiently.

[0054] Furthermore, since the index files 20d generated by the digital camera 1 and recorded in the external flash memory 20 are of a text format, even if many picture files are specified (grouped) as pictures to be copied, the size of the index files 20d does not significantly increase. Therefore, only a small memory capacity is required to record the index files 20d, thus effectively utilizing the storage capacity of the external flash memory.

[0055] Also in this embodiment, since the first through fourth operations keys 7a-7d function as the group specifying keys in the reproduction mode, and since a plurality of index files 20d are generated corresponding to the operations of the first through fourth operation keys 7a-7d, the pictures recorded in the external flash memory 20 can be classified and specified beforehand into a plurality of groups, for example, into a plurality of subject types such as a landscape and a portrait or into subject person groups, so that one or a plurality of the pictures can be rapidly copied at a time for each of thus classified groups. This facilitates use.

[0056] It should be noted that, in contrast to this embodiment, any one of the first through fourth operation keys 7a-7d may be specified to function as the group specifying key so that its operations may instruct the system to create only one index file 20d. Even in such a case, the same effect as this embodiment can be obtained. That is, the picture files can be copied easily and efficiently. Also in this case, since no index files 20d need to be specified in the personal computer 30, steps SB3 and SB4 of FIG. 7 can be omitted, so that copying starts immediately when the one index file 20d is retrieved from the external flash memory 20.

[0057] Furthermore, although according to the first embodiment the above-mentioned index files 20d are each generated following each of the dated folders 20b, the present invention is not limited thereto. For example, an index file 20d may be generated, for example, immediately following the DCIM folder 20a so that specified picture files 20c may be indicated over a plurality of the dated folders 20b. A number of the index files 20d may correspond to a number the group specifying keys (first through fourth operations keys) 7a-7d. Thus, rather than generating a plurality of index files 20d of the same group for each date, only one index file 20d must be generated for the group.

[0058] In addition, although according to the first embodiment the index file 20d may be generated in the external flash memory 20 based on the operations of the group specifying keys, the present invention is not limited thereto. For example, an index file 20d that corresponds to each of the group specifying keys (first through fourth operation keys) 7a-7d and that has no picture file name recorded may be generated beforehand, for example immediately when the external flash memory 20 is started in use.

[0059] Furthermore, although according to the first embodiment the apparatus body 2 of the digital camera 1 is provided with the first through fourth operation keys 7a-7d so that the user can selectively press each of these operation keys 7a-7d to thereby specify (select) a picture on the display 5 and also specify its group, the present invention is not limited thereto. For example, an operation key for specifying a desired picture and an operation key for further specifying it’s the group of the desired picture may be provided separately from each other; or the same operation key may be used to specify a desired picture and also to specify its group.

[0060] Furthermore, although according to the first embodiment the digital camera 1 has the display for displaying a through picture and a recorded picture, the present invention is not limited thereto. For example, a digital camera may be employed that does not have the display 5. In such a case, for example, when the shutter key 4 is pressed in photographing and if any one of the operation keys 7a-7d or a predetermined operation key is pressed, a picture file name of a previously photographed picture may be entered in an index file 20d which corresponds to an operated group specifying key. Alternatively, if any one of the operation keys 7a-7d or a predetermined key is pressed immediately before the shutter key is pressed in photographing, a picture file name of a picture photographed immediately afterward may be entered in an index file 20d which corresponds to an operated group specifying key.

[0061] Furthermore, although according to the first embodiment the external flash memory 20 is detached from the digital camera 1 and is subsequently attached to the card reader 41 of the personal computer 30 so that the personal computer 30 may acquire a picture file 20c and an index file 20d, the present invention is not limited thereto. For example, the picture file 20c and the index file 20d may be transferred from the digital camera 1 (later-described digital camera 51 of FIG. 11) to the personal computer 30 via cable communication, for example via a USB cable, or via wireless communication, for example via an infrared light, to be recorded on the hard disk 39 (or the RAM 33, the floppy disk, or the external flash memory 20) of the personal computer 30.

[0062] Furthermore, although according to the first embodiment the picture processing conducted on a picture file contained in a specified index file 20d is copying the picture file to other recording mediums, the present invention is not limited thereto. For example, the picture processing conducted on the picture file may be any other processing, for example, printing or display processing. In a case of printing processing conducted as the picture processing, only such a program needs to be prepared that when the user has specified any one of the index files 20d recorded in the external flash memory 20, one or a plurality of picture files 20c described in this specified index file 20d may be sequentially read out to the above-mentioned personal computer 30 to cause the printer 42 connected thereto to start printing.

[0063] Furthermore, although according to the first embodiment a fixed type of picture processing is conducted on a picture file described in a specified index file 20d, the present invention is not limited thereto. For example, any given picture processing selected by the user may be conducted.

[0064] The following will describe a specific example where the user selects any given picture processing, with reference to the drawings.

[0065] FIG. 8 is a flowchart for explaining a variant of the flowchart of FIG. 7.

[0066] Upon activation of the picture processing program, the personal computer 30 searches the external flash memory 20 for all the index files 20d following any dated folders 20b and lists them on the CRT 34 (step SB11), awaiting the specification of one or more of the index files 20d (step SB12).

[0067] Subsequently, when one or more of the index files 20d in the list displayed on the CFT 34 is specified (YES is answered at step SB12), the types of processing, such as copy, print, display, and other picture processing, are listed on the CRT34 (step SB13) and selection of a picture processing type is awaited (step SB14).

[0068] If the print processing is selected from the list (YES is answered at step SB14), a picture file (picture files) is read out from the external flash memory 20 that is identified by a picture file name contained in the index file 20d specified at step SB12, and the read out picture file is printed by the printer 42, thereby ending the process (step SB15).

[0069] If the copy processing is selected from the list (YES is answered at step SB14), on the other hand, a picture file (picture files) is read out from the external flash memory 20 that is identified by a picture file name contained in the index file 20d specified at step SB12, and the read out picture file is copied to another recording medium, thereby ending the process (step SB16).

[0070] If the display processing is selected from the list (YES is answered at step SB14), on the other hand, a picture file (picture files) is read out from the external flash memory 20 that is identified by a picture file name contained in the index file 20d specified at step SB12, and the read out picture file is displayed on the CRT 34, thereby ending the process (step SB17).

[0071] Furthermore, although as shown in the flowchart of FIG. 8 the type of picture processing to be conducted on a picture file described in a specified index file 20d is selected by hand, the present invention is not limited thereto. For example, the type of picture processing to be conducted may be automatically determined on the basis of a file type of the index file 20d.

[0072] The following will describe a specific example where the picture processing type is determined automatically, with reference to the drawings.

[0073] FIG. 9 is a flowchart for explaining a variant of the flowchart of FIG. 8.

[0074] Upon activation of the picture processing program, the personal computer 30 searches the external flash memory 20 for all the index files 20d following any dated folders 20b and lists them on the CRT 34 (step SB21) and then waits for specification of one or more of the index files 20d.

[0075] When, subsequently, one or more of the index files 20d is specified from the list (YES is answered at step SB22), the picture processing type is determined on the basis of a file name of the specified index file 20d (step SB23).

[0076] If the print processing is selected (YES is answered at step SB24), a picture file (picture files) is read out from the external flash memory 20 that is identified by a picture file name contained in the index file 20d specified at step SB22, and the read out picture file is printed by the printer 42, thereby ending the process (step SB25).

[0077] If the copy processing is selected at step SB23 (YES is answered at step 26), on the other hand, a picture file (picture files) is read out from the external flash memory 20 that is identified by a file name contained in the index file 20d specified at step SB22, and the read out picture file is copied to another recording medium, thereby ending the process (step SB27).

[0078] If the display processing is selected at step SB23 (NO is answered at step SB26), on the other hand, a picture file (picture files) is read out from the external flash memory 20 that is identified by a picture file name contained in the index file 20d specified at step SB22, and the read out picture file is displayed on the CRT 34, thereby ending the process (step SB28).

[0079] Although the flowchart of FIG. 7 has been described with a case where the index file 20d is specified by the user manually, the present invention is not limited thereto. For example, the index file 20d may be specified (selected) automatically.

[0080] For example, a printer-dedicated terminal (terminal comprised only of the CPU 31, ROM 32, RAM 33, card reader 41, and printer 42 shown in FIG. 5) that is capable of accepting the external flash memory 20 may be used as an external apparatus of the present invention so that a predetermined file name may be given beforehand to this terminal so as to automatically print one or a plurality of picture files 20c described in an index file 20d having the predetermined file name.

[0081] The following will describe a specific example of automatically specifying an index file to be printed, with reference to the drawings.

[0082] FIG. 10 is a flowchart for explaining a variant of the flowchart of FIG. 7.

[0083] Upon activation of the picture processing program, the print-dedicated terminal searches the external flash memory 20 for those index files 20d assigned a printing file name of all the index files 20d following any dated folders 20b (step SB31). If any one of such index files 20d is found (YES is answered at step SB32), the print-dedicated terminal reads out from the external flash memory 20 a picture file (picture files) identified by a picture file name contained in that printing index file 20d and prints the read out picture file using the printer 42, thereby ending the process (step SB33).

[0084] Although the flowchart of FIG. 10 has been described with a case where the present invention is applied to a print-dedicated terminal, the present invention is not limited thereto. For example, the present invention may be likewise applied to a display-dedicated terminal or a copy-dedicated terminal.

[0085] Furthermore, although FIG. 10 has been described with a case where the present invention is applied to a print-dedicated terminal, the present invention is not limited thereto. For example, the present invention may be applied to an external apparatus (personal computer 30 of FIG. 5) that can conduct all of the copy, print, and display processing items described along the flowcharts of FIGS. 8 and 9.

[0086] That is, when any one of the copy, print, and display processing items is specified (selected) and set and registered beforehand, processing as shown in FIG. 10 with respect to the print processing is conducted for the set and registered processing.

[0087] Second Embodiment

[0088] FIG. 11 is a block diagram for showing an electrical configuration of the digital camera 51 related to a second embodiment of the present invention. In addition to roughly the configuration as that of FIG. 2, the digital camera 51 has a data transfer section 52 connected to the address/data bus 17. The data transfer section 52 realizes an output section of the present invention and has an output terminal for attaching a communication cable (not shown), through which it is connected to an interface 36 of the personal computer 30 shown in FIG. 5. In this configuration, the picture files 20c and the index files 20d recorded in the external flash memory 20 are output to the personal computer etc. shown in FIG. 5. In this data transfer, signal processing is performed according to the predetermined standards of the RS232C, the USB, etc. The other sections of the digital camera 51 are the same as those of the digital camera 1 shown in FIG. 2 and so an explanation thereof is omitted.

[0089] With the digital camera 51 as described above, by grouping the pictures according to the flowchart of FIG. 6 corresponding to the user’s operations in the reproduction mode, the above-mentioned index file 20d can be created and stored in the external flash memory 20. The digital camera 51 itself can also be connected to the personal computer 30 through the communication cable with predetermined data-transfer link software installed in the personal computer, to transfer the picture file 20c to the personal computer 30.

[0090] FIGS. 12 and 13 are flowcharts for showing the operations of the digital camera 51 and the personal computer 30 respectively when the user transmits a predetermined picture file 20c recorded in the external flash memory 20 to the personal computer 30 with the digital camera 51 connected thereto via the communication cable.

[0091] That is, upon activation of the link software by the user, the personal computer 30 requests the digital camera 51 to send an index file thereto (step SC1). At this moment, the digital camera 51, after being connected with the communication cable, is waiting for a request for an index file, so that in response to a request from the personal computer (YES at step SD1), it reads out all the index files 20d recorded on the external flash memory 20 and transfers them to the personal computer 30 (step SD2).

[0092] Upon completion of reception of these index files 20d (YES at step SC2), the personal computer 30 in turn lists all the received index files 20d on the CRT 34 (step SC3) and waits for specification of one or more of the index files 20d (step SC4). If, subsequently, one or more of these listed index files 20d (e.g., “folderA.text”) is specified (YES is answered at step SC4), the personal computer requests the digital camera 51 to send each of the picture files described in the specified index file 20d (step SC5). In this step, the personal computer 30 sends the information of a file name of the picture file 20c and also a dated folder 20b where the picture file 20c exists to the digital camera 51.

[0093] The digital camera 51 responds to a request from the personal computer 30 (YES at step SD3) by reading out the requested picture files sequentially and transferring them to the personal computer 30 (step SD4) and, upon completion of the transfer of all the picture files (YES at step SD5), ends the process. The personal computer 30 in turn sequentially receives the picture files 20c requested at the step SC5 and copies them to a predetermined recording medium (drive) (step SC6). When all the requested picture files are copied (YES is answered at step SC7), the process end directly.

[0094] As according to the first embodiment, according to the second embodiment, therefore, the user can specify a copy-subject picture in the digital camera 51 beforehand to thereby copy a picture file easily and efficiently. Almost the same effects other than this as those described with the first embodiment can be obtained.

[0095] According to the second embodiment, the purpose in use (usage) of a specified picture may be any other purpose, for example, printing, instead of copying In such a case, desired pictures can be printed at a time immediately by operating a printer with which the digital camera 51 can be connected in much the same manner as mentioned above with respect to the personal computer 30. Moreover, it is possible to print only a desired picture without providing the printer with a display section required to confirm print-subject pictures. Further, by employing such a configuration that print-subject index files 20d are generated in the external flash memory 20 of the digital camera 51 while the printer is engaged in only the reading of those index files 20d, the printer need not specify any index file 20d, thus eliminating a need for the display section for specifying the index files 20d.

[0096] Although like the first embodiment, according to the second embodiment an index file 20d may be stored along with a picture file 20c into the external flash memory 20, the present invention is not limited thereto. For example, of course, these files 20c and 20d may be stored at different locations.

[0097] Besides the above-mentioned configurations, a password or an ID code may be recorded, in configuration, in one or all of the above-mentioned plurality of index files 20d for enabling the collation by the personal computer etc. when it engages in processing which corresponds to a predetermined use purpose of a picture file also only such processing that corresponds to a picture file 20c described in a collated index file 20d.

[0098] Furthermore, of course, the variations of the first embodiment (especially as shown in FIGS. 8-10) apply to the second embodiment as well. Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.

A method of storing an image in a digital camera, comprising the steps of: capturing the image using the selected quantization table. A method of storing an image in a digital camera, wherein the step of selecting a quantization table comprises the steps of: selecting a quality setting; compressing the image using a quantization table corresponding to the selected quality setting; decompressing the image; evaluating the decompressed image with the image quality metric; and, adjusting the quantization table such that the quality metric matches the selected quality setting.

Digital Camera Claims

1. A method of storing an image in a digital camera, comprising the steps of: a) capturing an image; b) selecting a quantization table based on an image quality metric that is dependent upon the captured image; and c) compressing the image using the selected quantization table.

2. The method claimed in claim 1, wherein the step b) of selecting a quantization table comprises the steps of: i) selecting a quality setting; ii) compressing the image using a quantization table corresponding to the selected quality setting; iii) decompressing the image; iv) evaluating the decompressed image with the image quality metric; and v) adjusting the quantization table such that the quality metric matches the selected quality setting.

3. The method claimed in claim 2, wherein the compressing step ii) is a JPEG compression step involving block DCT, quantization of DCT coefficients, and entropy coding of the quantized coefficients.

4. The method claimed in claim 2, wherein the decompressing step iii) is a JPEG decompression step involving entropy decoding, dequantization of DCT coefficients, and inverse block DCT.

5. The method claimed in claim 3, wherein the step ii) of compressing is performed without entropy coding and the step iii) of decompressing is performed without entropy decoding.

6. The method claimed in claim 4, wherein the step ii) of compressing is performed without entropy coding and the step iii) of decompressing is performed without entropy decoding.

Digital Camera Description

FIELD OF THE INVENTION

[0001] The present invention relates to digital image capture, and more particularly to a digital camera having a picture quality setting.

BACKGROUND OF THE INVENTION

[0002] Digital cameras such as the Kodak DC 280 apply JPEG compression prior to storing captured images in a camera memory card. JPEG compression involves performing a discrete cosine transform (DCT) on blocks of pixels (e.g. 8.times.8) of the image. The DCT coefficients are quantized to compress the image, and the quantized coefficients are entropy encoded (e.g. Huffman encoding) to produce the compressed image file. Such cameras may include a picture quality setting feature that allows the operator to select a quality option, for the image that is stored in the camera. The quality selection chooses a quantization table scale factor or quantization table used to quantize the DCT coefficients.

[0003] Generally a smaller image file results from a lower quality setting, and vice versa. One problem with this approach is that for a given quality setting images having different amounts of image detail will have different apparent quality. For example a very busy image compressed at an intermediate quality setting will have a low quality appearance, whereas an image with very little detail may have a high quality appearance even if it is compressed at the lowest quality setting.

[0004] There is a need therefore for an improved technique for accurately adjusting image quality in a digital camera.

SUMMARY OF THE INVENTION

[0005] The need is met according to the present invention by providing a method of storing an image in a digital camera, comprising the steps of: capturing an image; selecting a quantization table based on an image quality metric; and compressing the image using the selected quantization table.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] FIG. 1 shows a typical digital camera architecture.

[0007] FIG. 2 shows a block diagram of one embodiment of the current invention.

DETAILED DESCRIPTION OF THE INVENTION

[0008] Memory cards (i.e., CompactFlash card) are widely used by digital capture devices such as digital cameras to store captured images before they are transferred to other storage mediums. Due to the limited capacity of a memory card, digital cameras such as the Kodak DC 280 apply JPEG compression prior to storing captured images in a camera memory card. JPEG compression involves performing a discrete cosine transform (DCT) on blocks of pixels (e.g. 8.times.8) of the image. Image compression is achieved when the DCT coefficients are quantized with a quantization table. The quantized coefficients are entropy encoded (e.g. Huffman encoding) to produce the compressed image file.

[0009] Different levels of compression can be achieved with different quantization tables, and in general, the more an image is compressed, the lower the quality the image has, and vice versa. Therefore, digital cameras such as the Kodak DC 280 normally include a picture quality setting feature that allows the operator to select a quality option, essentially trading off between image quality and the number of images that can be stored in a memory card. Within the camera design, the quality selection actually chooses an appropriate quantization table used to quantize the DCT coefficients.

[0010] The current invention adds intelligence to the quantization table selection process by adding an image analysis step using certain image quality metric(s). With this image-dependent approach, consistent apparent quality may be achieved for images having different amounts of details.

[0011] Referring first to FIG. 1, a typical digital camera architecture is shown. Lights from a scene pass through camera lens 10, and are collected by the sensor 12. The sensor image is then sent to a signal processor 14 where various image processing steps may take place (i.e., CFA interpolation, color correction). A typical digital camera also has other peripherals such as RAM 18 where intermediate images are stored, memory card 20 where the captured images are finally stored. All these peripherals are normally controlled by a microprocessor controller 16 acting as a coordinator.

[0012] For camera settings (i.e., quality, date) as well as for image preview, a LCD 22 is also included in a typical digital camera along with buttons 24 26 28 for navigating within the LCD. For example, underneath the Quality Setting, a camera may let users select from three choices (as shown in FIG. 1):

[0013] “Best”, “Better” and “Good”, respectively. A user may press up arrow button 24 or down arrow button 28 to switch among these three settings, and then press the selection button 26 for final quality selection. All these actions are coordinated by the microprocessor controller, and the quality selection by a user will eventually be feedback to the microprocessor as well.

[0014] Referred to FIG. 2, which illustrates the flowchart for one embodiment of the current invention. A user selects a quality setting 40, then presses the button to capture an image 42. The digital camera processes the captured sensor image to produce a processed digital image for compression before storing it in the memory card. A copy of the processed digital image is stored in RAM. Based on the quality setting of the user, a default quantization table is selected 44 and is used to compress the digital image 46 to generate a compressed image. Assume the digital camera has three quality setting choices as shown in FIG. 2, three quantization tables (table-best, table-better, and table-good) are pre-selected to be the default tables for the corresponding quality setting choices. In another approach, one quantization table (table-best) is pre-selected as default quantization table for the “Best” quality setting selection, along with two scale factors (scale-better and scale-good). These two scale factors will be used to generate default quantization tables for “Better” and “Good” quality setting selections on the fly by scaling the entries of table-best. These default quantization tables as well as the scaling factors can be pre-determined through studying a large number of consumer type images as well as consumer preferences. A copy of the compressed image is stored in RAM.

[0015] The compressed image is then decompressed 48 to reconstruct the processed digital image. Image quality metric(s) is(are) further applied 50 to evaluate the quality of the reconstructed processed digital image. After that, a decision has to be made whether the quality of the reconstructed processed digital image meets the user requirement 52. If the image quality indicated by the image quality metric for the specific reconstructed processed digital image is appropriate for the user selected quality settings, then the copy of the compressed image in RAM is sent to the memory card for storage 54. Otherwise, a more appropriate quantization table is selected, the copy of the processed digital image is then retrieved from RAM and it goes through compression 46, decompression 48, and image quality evaluation 50 steps again, followed with another decision step 52. Recursive loops of step 44, 46, 48, 50 and 52 might be necessary until a satisfying result can be achieved.

[0016] For a three-level quality setting of “good”, “better” and “best” with three quantization tables, namely “coarse”, “medium” and “fine”, respectively, the number of recursive loops is limited to 2, incurring additional but reasonable computation. If the initially selected quantization table produces a compressed image with consistent quality to the user selected quality setting, the compressed image is sent to the memory card for storage and no further processing is needed; if the initially selected quantization table produces a compressed image with lower quality than the user selected quality setting, a finer quantization table, if still available, is used to compress the processed digital image, until a satisfying result is achieved; if the initially selected quantization table produces a compressed image with higher quality than the user selected quality setting, a coarser quantization table, if still available, is used to compress the processed digital image, until a satisfying result is achieved. Alternatively, all the available quantization tables can be used to compress the processed digital image, and a satisfying result is selected according to the image quality metric; however this procedure is computationally inefficient compared to the recursive procedure.

[0017] Major image quality issues associated with JPEG compression are the severity of blocking and contouring artifacts in a JPEG compressed image. Therefore, any image quality metric that correlates with visual perception of blocking and contouring artifacts may be used in the image quality evaluation step. In the embodiment of the current invention, the metric used is the one described in the commonly assigned U.S. patent application Ser. No. ______ (Docket No. 81593), filed on even date herewith in the names of Q. Yu and J. Luo and entitled “A Method of Detecting the Extent of Blocking and Contouring Artifacts in a Digital Image”, which is incorporated herein by reference. This metric measures both the amount of blocking and contouring artifacts within a JPEG compressed image, and predicts the image quality that will be perceived by consumers. More specifically, this metric is based on a digital image processing method that includes the steps of: forming a column difference image; averaging the values in the columns in the column difference image to produce a column difference array; computing the average of the values in the column difference array that are separated by one block width to produce a block averaged column difference array; locating the peak value in the block averaged column difference array; calculating the mean value of the block averaged column difference array excluding the peak value to produce a column base value; computing the ratio between the peak value and the base value to produce a column ratio; repeating steps the above steps in the row direction to produce a row ratio; and employing the column and row ratios as a measure of the extent of blocking artifacts in the digital image. In an additional series of steps the extent of contouring artifacts is determined by the steps of: locating block boundaries based on the locations of peak values of column and row difference arrays; calculating a DC value for each block; generating a histogram of the block DC values; calculating the Fourier transform of the histogram; locating the first non-DC peak in the Fourier transform domain; calculating a DC quantization step size based on the frequency of the first non-DC peak; and employing the DC quantization step size as a measure of the extent of the contouring artifacts in the digital image.

[0018] Note that the entropy encoding process in the compression step and the entropy decoding process in the decompression step cancel each other and they do not affect the image quality of the reconstructed processed digital image. Therefore, for implementation efficiency, these two steps are not included in the embodiment of current invention.

[0019] The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.

PARTS LIST

[0020] 10 camera lens [0021] 12 image sensor [0022] 14 signal processor [0023] 16 microprocessor controller [0024] 18 RAM [0025] 20 memory card [0026] 22 LCD [0027] 24 push button to increase quality setting [0028] 26 push button to select quality setting [0029] 28 push button to decrease quality setting [0030] 40 quality selection step [0031] 42 image capture step [0032] 44 quantization table selection step [0033] 46 image compression step [0034] 48 image decompression step [0035] 50 image quality evaluation step [0036] 52 image quality checking step [0037] 54 image storage step

Memory access bandwidth within a digital camera is allocated among several requestors by assigning each requester a “tokens per snapshot” (TPS) value. Each requestor has a DMA engine and a DMA entry queue. If the requester wishes to access the memory, then a DMA entry is pushed onto the DMA entry queue of the requester. An arbiter uses the TPS values to select DMA entries off the various queues for incorporation into a “snapshot”. The arbiter then selects DMA entries from the snapshot in an order for servicing such that memory access overhead in accessing the memory is reduced. Only after all DMA entries of the snapshot have been serviced is another snapshot of entries selected. Maximum latency in servicing a queue is controlled by assigning each queue a time out value (TOV). If a queue times out, then that queue is moved up in the order of servicing.

Digital Camera Claims

1. A camera, comprising: a memory that stores image information; a first DMA engine; a first queue for storing DMA request entries for the first DMA engine; a circuit that stores a first tokens per snapshot number (TPS1); a second DMA engine; a second queue for storing DMA request entries for the second DMA engine, wherein each DMA request entry in the first queue and each DMA entry in the second queue indicates an associated amount of data movement; a circuit that stores a second tokens per snapshot number (TPS2); and an arbiter that selects a first snapshot of DMA request entries having a first number of DMA request entries from the first queue and a second number of DMA request entries from the second queue, wherein TPS1 is used to determine the first number, and wherein TPS2 is used to determine the second number, and wherein the arbiter determines an-order that the DMA request entries in the first snapshot will be serviced by the first and second DMA engines.

2. The camera of claim 1, further comprising: an image sensor, wherein the first DMA engine moves raw image data received from the image sensor into the memory.

3. The camera of claim 1, further comprising: a zoom engine; and a compression engine, wherein the first DMA engine moves data between the zoom engine and the memory, and wherein the second DMA engine moves data between the compression engine and the memory.

4. The camera of claim 1, wherein the arbiter selects a second snapshot of DMA request entries, and wherein all the DMA request entries of the first snapshot are serviced before any DMA request entries of the second snapshot are serviced.

5. The camera of claim 1, wherein each of the DMA request entries includes an address, and wherein the arbiter determines the order by examining addresses of DMA request entries of the first snapshot, wherein there are multiple different possible orders of accessing said memory some of which have higher memory overhead than others, and wherein the arbiter orders the DMA request entries of the first snapshot so as to minimize memory access overhead.

6. The camera of claim 1, further comprising: a memory interface unit (MIU), wherein the first and second DMA engines issue memory access requests to the MIU in an order, the order of the memory access requests being the order that the DMA request entries in the first snapshot are serviced.

7. The camera of claim 6, wherein the MIU converts the memory access requests into corresponding memory commands, the memory commands being supplied to the memory.

8. The camera of claim 7, wherein the memory interfaces with the MIU via a command bus and a data bus, and wherein the MIU issues commands to the memory over the command bus at the same time that data is tranferred btween the MIU and the memory across the data bus.

9. The camera of claim 1, wherein the memory is a synchronous dynamic random access memory (SDRAM) integrated circuit, and wherein the first DMA engine, the first queue, the circuit that stores TPS1, the second DMA engine, the second queue, the circuit that stores TPS2, and the arbiter are not part of the SDRAM integrated circuit.

10. The camera of claim 1, wherein the first tokens per snapshot number (TPS1) is a number that represents an amount of time.

11. The camera of claim 1, wherein the first tokens per snapshot number (TPS1) is a number that represents an amount of data.

12. The camera of claim 1, wherein the first tokens per snapshot number (TPS1) is a number of DMA request entries.

13. The camera of claim 1, wherein the arbiter has a timer for determining whether a period of time associated with the first DMA engine has elapsed, and if the period of time has elapsed then the arbiter determines that a DMA request of the first snapshot from the first queue will be serviced before any other DMA request entries of the first snapshot are serviced.

14. The camera of claim 1, wherein after the first snapshot of DMA request entries has been selected the arbiter selects a second snapshot of DMA request entries, and wherein the number of DMA request entries in the first snapshot is identical to the number of DMA request entries in the second snapshot.

15. The camera of claim 1, wherein after the first snapshot of DMA request entries has been selected the arbiter selects a second snapshot of DMA request entries, and wherein the number of DMA request entries in the first snapshot is different from the number of DMA request entries in the second snapshot.

16. The camera of claim 1, wherein the arbiter successively selects snapshots of DMA requests entries, and wherein each snapshot of DMA request entries is serviced in a window of time, and wherein the windows of time of each of the snapshots is an identical amount of time.

17. The camera of claim 1, wherein the arbiter successively selects snapshots of DMA requests entries, and wherein each snapshot of DMA request entries is serviced in a window of time, and wherein the windows of time of the various snapshots are differnet amounts of time.

18. A method of allocating memory access bandwidth among a plurality of requesting entities in a digital camera, each of the requesting entities having a queue for storing DMA request entries, each DMA request entry being a request to perform an access of a memory integrated circuit in the digital camera, wherein each of the requesting entities has a tokens per snapshot (TPS) value, the method comprising: (a) selecting a snapshot of DMA request entries by selecting, for each queue, a number of DMA request entries based on the TPS value for the requesting entity associated with the queue; (b) servicing the DMA request entries in the snapshot in an order that reduces memory access overhead associated with performing the memory accesses requested by the DMA request entries in the snap shot; and (c) repeating steps (a) and (b).

19. The method of claim 18, wherein each tokens per snapshot (TPS) value is a number of tokens, and wherein a token represents one DMA request entry.

20. The method of claim 18, wherein each tokens per snapshot (TPS) value is an indication of an amount of data movement, and wherein each DMA request entry comprises an indication of an amount of data movement.

21. The method of claim 18, wherein each tokens per snapshot (TPS) value is an indication of an amount of time.

22. The method of claim 18, wherein one of the requesting entities is a compression engine.

23. The method of claim 18, wherein no DMA request entries are selected in (a) from a queue if there are no DMA request entries in the queue.

24. The method of claim 18, wherein the memory integrated circuit is a dynamic random access memory (DRAM) integrated circuit, and wherein the memory access overhead reduced in (b) includes overhead associated with performing a refresh operation on the DRAM integrated circuit.

Digital Camera Description

TECHNICAL FIELD

[0001] The present invention relates to a digital camera that has a plurality of functional parts that require access to a memory that has a limited memory access bandwidth.

BACKGROUND

[0002] Conventional consumer market digital cameras typically involve image processing circuitry as well as a separate memory integrated circuit. The memory integrated circuit may, for example, be a synchronous dynamic random access memory (SDRAM).

[0003] Images are captured by an image sensor. The image sensor outputs a stream of raw image information that is stored into the memory. In the case of video or a rapid sequence of still images, the flow of image information can be a fairly constant stream. At the same time that raw image information later in the stream is being stored into the memory, image information earlier in the stream is being read out of the memory for image processing by a digital image pipeline (DIP). The digital image pipeline may include several processing blocks. A first image processing block may be operating on a first part of the image stream, whereas a second image processing block is operating on a second part of the image stream. Each block may read image information from the memory, perform processing, and then write the resulting processed information back out to the memory. Several blocks of the digital image pipeline may therefore attempt to access the memory at the same time.

[0004] Not only can different blocks of the digital image pipeline require access to the memory, but there may be other blocks of functionality on the digital camera that require memory access as well. In one example, the digital camera includes a JPEG compression block. The JPEG compression block reads an image out of the memory, compresses the image, and then outputs a compressed version of the image and stores the compressed version back to the memory. The digital camera typically has a zoom engine that reads an image out of the memory, creates a smaller version of the image called a “thumbnail,” and then writes this thumbnail back to the memory. The digital camera typically has a display that the user can use to view the image about to be captured. The thumbnail may be read out from memory and may be supplied to the display for viewing. The digital camera may also have the ability to overlay an icon or text information over an image. An on-screen display (OSD) engine may read a background image out of the memory, superimpose the icon or text or other visual feature on top of the background image, and then write the composite image back out to memory for viewing on the camera’s display. A camera may also include a video encoder/decoder such as, for example, an MPEG2 codec. Image information may be read out of memory and sent through the MPEG2 codec. The resulting MPEG2 stream output by the MPEG2 codec may then be returned to memory.

[0005] The memory integrated circuit typically has a single access port that is used to write information into the memory and that is used to read information out of the memory. Due to the multiple different entities that need to read image information out of the memory integrated circuit, and the need to write image information into the memory integrated circuit, the access port of the memory integrated circuit is often times a throughput bottleneck in the camera. There is a limited amount of data that can be moved across the access port per unit time. In order for the camera to operate properly, the total amount of data to be moved either into or out of the memory by each of the accessing entities must total to a number less than the maximum memory access bandwidth of the memory integrated circuit.

[0006] Not only must the total memory access bandwidth required by all the accessing entities be less than the available memory access bandwidth available over the long term, but each of the accessing entities must not be made to wait too long to access the memory. The amount of time it takes to access the memory is sometimes referred to latency. If an accessing entity is made to wait too long, then operation of that entity may fail or be slowed or halted, thereby decreasing overall throughput of the camera. Some accessing entities may not be able to accommodate as much latency as other entities. The flow of video image information from the image sensor into the memory is one such process that typically can only tolerate a low amount of latency. If raw video image information being output from the image sensor cannot be stored within a certain amount of time, then it may be overwritten thereby resulting in the loss of raw image information. Other accessing entities, in contrast, can generally wait to access memory as long as over the long term those entities receive their required amount of access to the memory.

[0007] In one conventional digital camera, the total memory access bandwidth and latency issues are handled using an arbiter. Each of the accessing entities has its own dedicated DMA engine or engines. Within each accessing entity there may be sub-entities that access memory. When one of the accessing entities needs to access the memory, its DMA engine makes a request to the arbiter. If there is only one DMA engine making a request, then the request is granted and the accessing entity gains access to the memory. If there are multiple DMA engines making simultaneous requests, then one of the DMA engines is selected based on a strict priority or round robin arbitration scheme. If, for example, the DMA engine that moves raw image data from the image sensor into the memory is making a request at the same time that the zoom engine’s DMA engine is making a request, then the DMA engine for the raw image data will typically have its request granted and the zoom engine’s DMA engine will typically have to wait. To prevent latency problems, the system is designed so that so many high priority requests cannot be submitted in such a short period of time that the latency and bandwidth requirements of the lowest priority DMA engines are violated. Controlling when DMA engines can make requests and making sure that latency and throughput requirements of each of the requesting entities are not violated can give rise to difficult system design issues. If the system is changed, for example, then timing of the various DMA engines and the timing of their requests can change in complex ways. Reanalysis of the interplay between the various processing blocks of the system may be required. Flow shaping and scheduling are employed in the design of routers and switches in the networking and the telecommunications arts to handle bandwidth and latency issues. These techniques are, however, generally complex and tend to be expensive and cumbersome to implement. An inexpensive solution is desired that is suitable for use in a price-sensitive consumer market digital camera.

SUMMARY

[0008] A memory (for example, a synchronous dynamic read only memory–SDRAM) of a digital camera stores image information and has a single access port. Image information is both read out of the memory, and is written into the memory across this single access port. Memory access bandwidth on this access port is allocated among several requesters of the image information by assigning each requestor a “tokens per snapshot” (TPS) value. The tokens per snapshot value may, for example, be a number that indicates a number of DMA request entries. Each of the requesters has a DMA engine and a DMA request entry queue. If the requester wishes to access the memory, then a DMA request entry is pushed onto the DMA request entry queue of the requestor. This DMA request entry indicates, among other things, whether the access is to be a read or a write and the starting address to be accessed within the memory.

[0009] An arbiter block uses the TPS values of the various requesters to select DMA request entries off the various DMA request queues. If, for example, a given requestor is assigned a TPS value of two, then the arbiter block can select two DMA request entries off the queue (provided that there are two DMA entries on that queue). If there are less than two DMA request entries on the queue, then the arbiter block selects as many DMA entries as it can from the queue. In this way, the arbiter block selects DMA request entries from each queue. The resulting set of selected DMA request entries is called a “snapshot”.

[0010] Once the snapshot is selected, the arbiter block selects DMA request entries from the snapshot in an order for servicing such that memory access overhead in accessing the memory is reduced or minimized. Before a DMA request entry is selected for servicing, however, a “service time out value” (STOV) stored in association with each queue is checked. The service time out value is a value that indicates a time after which a DMA request entry on the queue should be serviced irrespective of the fact that servicing the DMA request entry immediately would result in an order of servicing DMA request entries that does not result in the minimal memory access overhead. Accordingly, the arbiter block checks a timer to see if any of the service time out values has elapsed. If a queue is determined to have timed out, then the next DMA request entry selected out of the snapshot for servicing is the oldest DMA request entry off that queue.

[0011] Each queue has a register in which a time out value (TOV) is stored. When a DMA request entry is selected for servicing by the arbiter block, the current time as indicated by the timer is added to the time out value (TOV). The resulting time becomes the service time out value (STOV) for the queue.

[0012] Once all the DMA request entries of the snapshot have been selected for servicing, then the arbiter block selects the next snapshot of DMA request entries. When a DMA request entry is selected for servicing by the arbiter block, the DMA engine associated with the DMA request entry issues either reads and/or writes to the SDRAM via a memory interface unit (MIU). The MIU translates the reads and/or writes into memory commands understood by the particular memory used. If possible, the MIU supplies any necessary memory commands such as activate commands, column read commands, column write commands and precharge commands to the memory at the same time that data is being transferred either into or out of the memory. Providing activate, column read, column write and precharge commands in this fashion reduces memory access overhead.

[0013] Both the tokens per snapshot (TPS) value and the time out (TOV) value for each queue can be written by a processor. Increasing the tokens per shapshot (TPS) value of a queue increases the amount of memory access bandwidth allocated to the requester associated with the queue relative to other requesters. Decreasing the time out (TOV) value of a queue reduces the maximum amount of time between successive servicings of DMA request entries of the queue and therefore reduces memory access latency for the associated requester.

[0014] Although a token indicates a DMA request entry in the example described above, a token may represent other quantities that allow the TPS values to be used to allocate memory access bandwidth among numerous requesters. A token may, for example, represent an amount of time that a requester is allowed to use the access port of the memory. A token may, for example, represent an amount of data that the DMA engine of the requester is allowed to move either into or out of the memory.

[0015] Although all the DMA request entries in the example described above correspond to an equal amount of data movement, this need not be the case. In one example, DMA request entries can indicate different amounts of data movement. The amounts of data movement for the DMA request entries on the bottom of a queue are summed to determine how many of the DMA request entries on the bottom of the queue amount to the tokens per snapshot (TPS) value for the queue. Alternatively, DMA entries can indicate different amounts of time such that the amounts of time for the DMA request entries on the bottom of a queue are summed to determine how many of the DMA request entries on the bottom of the queue amount to the tokens per snapshot (TPS) value for the queue.

[0016] Other embodiments and advantages are described in the detailed description below. This summary does not purport to define the invention. The invention is defined by the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, where like numerals indicate like components, illustrate embodiments of the invention.

[0018] FIG. 1 is a diagram of a digital camera in accordance with one embodiment of the present invention.

[0019] FIG. 2 is a simplified flowchart of the selection of DMA request entries for incorporation into a snapshot, and of the subsequent granting of the DMA request entries of the snapshot.

[0020] FIGS. 3, 6 and 7 illustrate the selection of two consecutive snapshots of DMA request entries.

[0021] FIG. 4 illustrates one possible organization of an SDRAM integrated circuit.

[0022] FIG. 5 is a simplified flowchart that illustrates how the granted DMA request entries pass through the MIU and are translated into memory commands by the MIU.

[0023] FIG. 8 illustrates a potential latency problem associated with the example of FIGS. 3, 6 and 7.

[0024] FIG. 9 illustrates how the latency problem illustrated in FIG. 8 may be solved in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION

[0025] Reference will now be made in detail to some embodiments of the invention, examples of which are illustrated in the accompanying drawings.

[0026] FIG. 1 is a simplified block diagram of a digital camera 1 in accordance with one embodiment of the present invention. Camera 1 includes image processing circuitry 2 and a memory integrated circuit 3. Memory integrated circuit 3 is, for example, a single Synchronous Dynamic Random Access Memory (SDRAM) integrated circuit that stores image information.

[0027] Image processing circuitry 2 includes a plurality of requesting entities. Each of these requesting entities includes a DMA engine. FIG. 1 shows a DMA engine 4 that transfers raw image information output from an image sensor into the SDRAM 3, a DMA engine 5 of a digital image pipeline, a DMA engine 6 of a zoom engine, a DMA engine 7 that transfers information to a display such as an LCD display, and a DMA engine 8 of a JPEG compression engine. Image processing circuitry 2 further includes memory interface unit (MIU) 9, an arbiter block 10, and a plurality of queues 11-15. If a DMA engine accesses SDRAM 3, it does so through MIU 9. If, for example, DMA engine 4 were to read from SDRAM 3, then DMA engine 4 would issue a series of reads to MIU 9 over parallel DMA bus 16, when allowed to do so by the arbiter. The reads would be buffered in a first-in-first-out memory 17 within MIU 9. MIU 9 would then translate the reads into memory commands understood by SDRAM 3. For example, before a memory location can be read from SDRAM 3, SDRAM 3 may require that the memory bank containing the desired location be “activated.” MIU 9 has the intelligence to know that the bank needs to be activated, and generates the necessary activate command that causes SDRAM 3 to activate the bank. The activate command, along with a row address for the subsequent memory access, is supplied onto a command bus 18 of SDRAM 3. After sending the activate command and the row address across command bus 18, MIU 9 sends an appropriate memory read command to SDRAM 3. A column address for the subsequent memory access is supplied along with the memory read command via command bus 18. SDRAM 3 returns the contents of the location indicated by the bank, row and column addresses to MIU 9 via a 16-bit wide parallel data bus 19. The command bus 18 and the data bus 19 together comprise a double data rate (DDR2) access port of SDRAM 3. All reads and writes to SDRAM 3 occur across this single access port. For more information on operation of the access port, see: JEDEC standard “DDR2 SDRAM Specification”, JESD79-2A, January 2004, published by the JEDEC Solid State Technology Association, 2500 Wilson Boulevard, Arlington, Va. 22201 (the subject matter of which is incorporated herein by reference).

[0028] Arbiter block 10 includes an arbiter 20, a timer 21, a plurality of tokens per snapshot (TPS) registers 22-26, and a plurality of time out value (TOV) registers 27-31. There is one TPS register and one TOV register for each of the DMA engines. A processor (not shown) that controls operation of the various blocks of the image processing circuitry 2 can write to the various TPS and TOV registers via a parallel bus 32. In one embodiment, the processor is an ARM processor and bus 32 is an AMBA compliant 32-bit data bus.

[0029] When camera 1 is operating, the various requesting entities through their respective DMA engines push DMA request entries onto their respective queues. In the illustration, a DMA request entry is pushed onto the top of the already-present DMA entries in a queue. Each DMA request entry is either a request to read an amount of data from SDRAM or a request to write an amount of data to SDRAM. The amount of data is, in the present example, sixteen bytes for both a read request entry and a write request entry. Each DMA read request entry includes the starting address of the first byte to be read from SDRAM, as well as an indicator bit that indicates that the request is a read request. Each DMA write request entry includes a starting address of the first location in SDRAM into which the data is to be written, as well as an indicator bit that indicates that the request is a write request.

[0030] In the present example, DMA engine 4 pushes write requests onto queue 11. DMA engine 4, when given authorization to do so by arbiter block 10, moves raw image information coming from the image sensor (not shown) of the camera into SDRAM 3. DMA engine 5 is the DMA engine for the digital imaging pipeline (DIP). DMA engine 5 pushes DMA read request entries onto queue 12. When given authorization to do so by arbiter block 10, DMA engine 5 reads raw image information out of SDRAM 3 and transfers the information to the DIP. The DIP processes the image information. DMA engine 5 then pushes DMA write request entries onto queue 12 to be given authorization to write the output of the DIP back into SDRAM 3. Similarly, DMA engine 6 of the zoom engine pushes both read requests and write requests onto queue 13. DMA engine 7 pushes read requests onto queue 14. DMA engine 8 of the JPEG engine pushes read requests and write requests onto queue 15. FIG. 1 shows each of the queues 11-15 containing DMA request entries. The “SA” designation in FIG. 1 indicates the “starting address” portion of the DMA request entry.

[0031] Arbiter block 10 determines which of the DMA request entries will be granted first and therefore which of the DMA engines will be able to access SDRAM 3 first. After arbiter block 10 has determined which DMA request entry will be granted, it returns a grant signal to the appropriate DMA engine by a dedicated acknowledge signal line. No grant signals are supplied to the other DMA engines by their respective grant lines. The grant lines are indicated by numerals 33-37. The DMA engine that received the grant then retrieves the oldest DMA request on its queue. The oldest DMA request entry in each queue in the illustration of FIG. 1 is DMA request entry that is on the bottom of the queue. The DMA engine services this oldest DMA request entry as set forth above by issuing reads and/or writes to MIU 9. MIU 9 converts the reads and/or writes into memory commands appropriate for SDRAM 3 in accordance with the JEDEC standard referenced above.

[0032] When a DMA engine has serviced the oldest DMA request by issuing reads and/or writes to MIU 9, then the DMA engine sends a done signal to arbiter block 10 via a dedicated done signal line. The done signal lines are indicated by numerals 38-42. When arbiter block 10 receives the done signal, arbiter block 10 determines the next DMA request entry that will be granted.

[0033] How arbiter block 10 determines which DMA request entry to grant is as follows and as set forth in FIG. 2. First (step 100 of FIG. 2), arbiter block 10 uses the tokens per snapshot (TPS) values for each of the queues to determine the number of DMA request entries to select out of each DMA queue. In the present example, a token per snapshot (TPS) number is a number in units of DMA request entries. A token per snapshot (TPS) number of two, for example, indicates two DMA request entries.

[0034] The set of selected DMA request entries is referred to here as a “snapshot” of DMA request entries. All the DMA request entries in the snapshot will be granted before any other DMA request entries are granted. Once a first snapshot of entries is granted, then a second snapshot of entries can be selected. Only after the first snapshot of DMA request entries is granted can the second snapshot of DMA request entries be granted. This process repeats. If a first DMA engine is to be allocated twice the amount of memory access bandwidth as a second DMA engine, then the first DMA engine should be allocated twice as many DMA entries per snapshot on average as the second DMA engine receives. The tokens per snapshot (TPS) value for this first DMA engine will therefore be set to be twice as large as the tokens per snapshot (TPS) value for the second DMA engine.

[0035] FIG. 3 illustrates an example in which a first snapshot of DMA request entries is selected. The tokens per snapshot (TPS) value for each of the DMA engines 4-8 is 1, 4, 2, 2, and 6, respectively. There is no DMA request entry in queue 11. No DMA request entry is therefore selected from queue 11 even though the tokens per snapshot (TPS1) value for queue 11 is one. The first four DMA entries of queue 12 are selected, the first two DMA entries of queue 13 are selected, the first two DMA entries of queue 14 are selected, and the first three DMA entries of queue 15 are selected. Only three DMA entries of queue 15 are selected even though the TPS value for DMA engine 8 is six. This is because queue 15 only contains three DMA entries. The line 200 in FIG. 3 represents the DMA entries selected.

[0036] Once the first snapshot of DMA entries is selected, arbiter 20 selects a DMA request entry for granting (step 101 of FIG. 2) as follows. When a DMA request entry for a particular DMA engine has been granted (for example, as indicated by receipt of a done signal from the DMA engine), then a service time out value STOV (not shown) for the DMA engine is reset to be the current time as maintained by timer 21 plus the time out value TOV stored in the TOV register corresponding to the DMA engine. If the DMA engine does not have its next DMA request entry granted by the time the service time out value STOV arrives (as indicated by timer 21), then arbiter 20 selects the next DMA request entry to be granted to be the oldest DMA request entry for that DMA engine. Accordingly, arbiter 20 checks to see if any of the DMA queues have timed out (step 101 of FIG. 2).

[0037] If a DMA queue has timed out, then the next DMA entry for the timed out DMA queue is the next DMA request to be granted. If no DMA queue has timed out, then arbiter 20 selects the next DMA request entry (step 101 of FIG. 2) in the snapshot for granting so as to minimize SDRAM access overhead. Ways of minimizing SDRAM access overhead are explained in further detail below. If all the DMA request entries in the snapshot have not been granted (step 104 of FIG. 2), then the process of granting DMA request entries (step 101) continues until all DMA request entries in the snapshot have been granted. Once all the DMA request entries of the snapshot have been granted, processing returns to step 100 and a subsequent snapshot of DMA request entries is selected.

[0038] The order in which DMA request entries are granted within a snapshot is chosen such that memory access overhead is reduced or minimized. Certain orders of granting DMA request entries may result in more memory access overhead than others. Arbiter 20 has intelligence to be able to select an order of DMA request entry granting that reduces or minimizes this overhead for the particular type of memory being accessed. How this is done is described in connection with FIG. 4.

[0039] FIG. 4 illustrates a typical SDRAM integrated circuit 30. SDRAM 30 is a 64 megabyte SDRAM, having four banks 31-34 of memory cells. Each bank has 16 megabytes of memory cells. Each bank is made up of many 1 k byte pages of memory cells. If a page in a first bank is being accessed, and then the next access is an access to the same page in the same bank, then the SDRAM integrated circuit does not require that the bank be either precharged or activated (unless there was some other intervening non-access related event, such as refresh). The second access can follow the first access without any special precharge command or any special activate command having to be sent to the SDRAM before the second access can be made.

[0040] If, however, the first access is of a page within a bank and the next access is of another page in the same bank, then the second page must be activated before the second access can be made. A activate command is sent to SDRAM 3 via command bus 18. Only after the second page has been activated, can the second access be performed. Accordingly, there is a memory access bandwidth penalty to performing this order of memory accesses.

[0041] If a first access is of a page within a first bank and the next access is of a page in another bank, then there may or may not be a memory access bandwidth penalty. Before the second access can be made, the second page must be activated. The SDRAM can, however, be instructed to perform this activation at an earlier time such that the activation to read or write delay is satisfied. If the activate command can be sent to the SDRAM over the command bus 18 (overlapping with the data transfer for some prior read or write access) prior to the activation to read or write time, then the memory access bandwidth penalty associated with this order of accessing is minimized. If, on the other hand, the activate command for the second access cannot be sent to the SDRAM early enough to satisfy the activation to read or write delay, then this delays the second access and constitutes a memory access bandwidth penalty. Arbiter 20 knows how to order the granting of the DMA entries within first snapshot 200 (see FIG. 3) such that the memory access bandwidth penalty associated with accessing SDRAM 3 is reduced or minimized.

[0042] In one embodiment, arbiter 20 examines the starting addresses of all the DMA entries of the snap shot while the DMA entries of the snapshot are still in their various queues. Arbiter 20 can remove any DMA entry in a queue and pass that DMA entry to its corresponding DMA engine even if the DMA entry is not the bottom-most (the oldest) DMA entry on that queue, provided that the DMA entry removed is within the snapshot. This allows arbiter 20 to remove the DMA entries of the snapshot and pass them to the DMA engines in any order such that the memory access bandwidth penalty is reduced or minimized.

[0043] FIG. 5 is a flowchart that illustrates how granted DMA request entries are converted into commands that cause the memory accesses to occur. First (step 102 of FIG. 5), a DMA engine that receives a grant via its grant line issues a memory read or a memory write across DMA bus 16 as if the DMA engine were reading or writing from MIU 9. The memory reads and writes from the various DMA engines accumulate in the FIFO 17 within MIU 9. Next (step 103 of FIG. 5), MIU 9 examines the stream of memory reads and memory writes in FIFO 17 and pipelines any needed precharge and activate commands with prior memory accesses if it is possible to do so. Arbiter 20 and MIU 9 therefore work together to deal with the idiosyncrasies of the particular SDRAM used in order to reduce memory access overhead. MIU 9 converts the memory reads and memory writes in FIFO 17 into appropriate memory commands that are supplied to SDRAM 3 across command bus 18. MIU 9 also supplies data to SDRAM 3 via data bus 19 for memory writes and receives data from SDRAM 3 via data bus 19 for memory reads.

[0044] FIG. 6 illustrates DMA request entries being pushed onto queues 11 and 15 immediately after the first snapshot 200 of DMA entries of FIG. 3 has been selected. DMA request entry 201 is a new DMA request entry pushed onto queue 11. In this example, there are also new DMA request entries pushed onto queue 15. As set forth above, all entries of the first snapshot are granted before any of these newly pushed DMA request entries is selected for incorporation into a snapshot.

[0045] FIG. 7 illustrates a subsequent step in which a second snapshot 202 of DMA request entries is taken. Again, arbiter 20 uses the tokens per snapshot (TPS) values in registers 27-31 to determine how many DMA request entries, if present, to select from each queue. The tokens per snapshot value TPS1 for DMA engine 4 is one, so the newly added DMA entry 201 is selected for incorporation into the second snapshot. The tokens per snapshot value TPS2 for DMA engine 5 is four, but there are only two DMA entries on queue 12. Only two DMA entries from queue 12 are therefore selected. The tokens per snapshot TPS5 for DMA engine 8 is six, and there are six DMA entries on queue 15, so six DMA entries are selected from queue 15. The selected DMA request entries are shown enclosed in line 202 in FIG. 7.

[0046] FIG. 8 illustrates a latency issue that can appear in the situation of FIGS. 3, 6 and 7. The maximum amount of time to grant a DMA entry from queue 11 is approximately two snapshots worth of memory access time. This occurs in the situation in which a DMA request entry such as DMA request entry 201 arrives shortly after the selection of the entries for the first snapshot, and where the DMA request entry 201 ends up to be the last DMA request entry granted in the second snapshot. FIG. 8 illustrates such a situation.

[0047] If the latency associated with the situation of FIG. 8 cannot be tolerated by DMA engine 4, then the time out value TOV1 for queue 11 is set such that DMA queue 11 will time out at an earlier time. DMA engine 4 that transfers raw image information from the image sensor and places that raw image information into SDRAM 3 may, for example, only be able to tolerate a relatively small amount of latency when it tries to transfer data to SDRAM 3. If DMA engine 4 is made to wait too long when it is trying to write raw image information into SDRAM 3, then the raw image information may be overwritten thereby resulting in a loss of raw image information. This latency problem is to be avoided.

[0048] FIG. 9 illustrates an example in which the time out value TOV1 is set to be smaller than the amount of time it takes for the granting of eleven DMA requests (the eleven DMA requests of the first snapshot). Accordingly, because an entry off the bottom of queue 11 has not been granted for this amount of time, DMA queue 11 times out during the granting of the first snapshot of DMA request entries. When the second snapshot of DMA request entries is selected, and selection of which DMA request entries in the second snapshot to grant begins, the DMA request entry 201 is selected for granting before other DMA request entries of the second snapshot the queues of which have not timed out. Note that DMA request entry 201 in FIG. 9 is granted at the beginning of the granting of the thirteen DMA request entries of the second snapshot, rather than at the end of the granting of the thirteen DMA request entries of the second snapshot at illustrated in FIG. 8.

[0049] Although the present invention has been described in connection with certain specific embodiments for instructional purposes, the present invention is not limited thereto. The technique of selecting a snapshot of DMA request entries is not limited to use in digital cameras, but rather is a general-purpose technique usable to control access to a memory. Although the entities making requests to access the memory may be DMA engines in some embodiments, other types of entities can be requesting entities. Processors and specific-purpose state machines can be requesting entities. Although the invention is described in connection with controlling access to one memory integrated circuit, the invention is usable to control access to multiple integrated circuits. The memory to which access is controlled need not be a separate integrated circuit from the arbiter circuitry, but rather both the arbiter circuitry and the memory can be integrated on the same integrated circuit. Although bus 16 is illustrated as a bus wherein a single group of bus conductors carry information from a selected one of the DMA engines 4-8 to MIU 9, this need not be the case. DMA bus 16 need not have conductors over which signals pass in a bidirectional fashion. For example, the outputs of DMA engines 4-8 can be supplied to the data input leads of a multiplexer and the select input leads of the multiplexer can be controlled by the arbiter to couple a selected one of the DMA engines 4-8 to MIU 9. Although the technique of using snapshots to allocate memory access bandwidth is described above in connection with a digital camera, the technique is applicable in any system involving a memory. Accordingly, various modifications, adaptations, and combinations of various features of the described embodiments can be practiced without departing from the scope of the invention as set forth in the claims.

Memory access bandwidth within a digital camera is allocated among several requestors by assigning each requester a “tokens per snapshot” (TPS) value. Each requestor has a DMA engine and a DMA entry queue. If the requester wishes to access the memory, then a DMA entry is pushed onto the DMA entry queue of the requester. An arbiter uses the TPS values to select DMA entries off the various queues for incorporation into a “snapshot”. The arbiter then selects DMA entries from the snapshot in an order for servicing such that memory access overhead in accessing the memory is reduced. Only after all DMA entries of the snapshot have been serviced is another snapshot of entries selected. Maximum latency in servicing a queue is controlled by assigning each queue a time out value (TOV). If a queue times out, then that queue is moved up in the order of servicing.

Digital Camera Claims

1. A camera, comprising: a memory that stores image information; a first DMA engine; a first queue for storing DMA request entries for the first DMA engine; a circuit that stores a first tokens per snapshot number (TPS1); a second DMA engine; a second queue for storing DMA request entries for the second DMA engine, wherein each DMA request entry in the first queue and each DMA entry in the second queue indicates an associated amount of data movement; a circuit that stores a second tokens per snapshot number (TPS2); and an arbiter that selects a first snapshot of DMA request entries having a first number of DMA request entries from the first queue and a second number of DMA request entries from the second queue, wherein TPS1 is used to determine the first number, and wherein TPS2 is used to determine the second number, and wherein the arbiter determines an-order that the DMA request entries in the first snapshot will be serviced by the first and second DMA engines.

2. The camera of claim 1, further comprising: an image sensor, wherein the first DMA engine moves raw image data received from the image sensor into the memory.

3. The camera of claim 1, further comprising: a zoom engine; and a compression engine, wherein the first DMA engine moves data between the zoom engine and the memory, and wherein the second DMA engine moves data between the compression engine and the memory.

4. The camera of claim 1, wherein the arbiter selects a second snapshot of DMA request entries, and wherein all the DMA request entries of the first snapshot are serviced before any DMA request entries of the second snapshot are serviced.

5. The camera of claim 1, wherein each of the DMA request entries includes an address, and wherein the arbiter determines the order by examining addresses of DMA request entries of the first snapshot, wherein there are multiple different possible orders of accessing said memory some of which have higher memory overhead than others, and wherein the arbiter orders the DMA request entries of the first snapshot so as to minimize memory access overhead.

6. The camera of claim 1, further comprising: a memory interface unit (MIU), wherein the first and second DMA engines issue memory access requests to the MIU in an order, the order of the memory access requests being the order that the DMA request entries in the first snapshot are serviced.

7. The camera of claim 6, wherein the MIU converts the memory access requests into corresponding memory commands, the memory commands being supplied to the memory.

8. The camera of claim 7, wherein the memory interfaces with the MIU via a command bus and a data bus, and wherein the MIU issues commands to the memory over the command bus at the same time that data is tranferred btween the MIU and the memory across the data bus.

9. The camera of claim 1, wherein the memory is a synchronous dynamic random access memory (SDRAM) integrated circuit, and wherein the first DMA engine, the first queue, the circuit that stores TPS1, the second DMA engine, the second queue, the circuit that stores TPS2, and the arbiter are not part of the SDRAM integrated circuit.

10. The camera of claim 1, wherein the first tokens per snapshot number (TPS1) is a number that represents an amount of time.

11. The camera of claim 1, wherein the first tokens per snapshot number (TPS1) is a number that represents an amount of data.

12. The camera of claim 1, wherein the first tokens per snapshot number (TPS1) is a number of DMA request entries.

13. The camera of claim 1, wherein the arbiter has a timer for determining whether a period of time associated with the first DMA engine has elapsed, and if the period of time has elapsed then the arbiter determines that a DMA request of the first snapshot from the first queue will be serviced before any other DMA request entries of the first snapshot are serviced.

14. The camera of claim 1, wherein after the first snapshot of DMA request entries has been selected the arbiter selects a second snapshot of DMA request entries, and wherein the number of DMA request entries in the first snapshot is identical to the number of DMA request entries in the second snapshot.

15. The camera of claim 1, wherein after the first snapshot of DMA request entries has been selected the arbiter selects a second snapshot of DMA request entries, and wherein the number of DMA request entries in the first snapshot is different from the number of DMA request entries in the second snapshot.

16. The camera of claim 1, wherein the arbiter successively selects snapshots of DMA requests entries, and wherein each snapshot of DMA request entries is serviced in a window of time, and wherein the windows of time of each of the snapshots is an identical amount of time.

17. The camera of claim 1, wherein the arbiter successively selects snapshots of DMA requests entries, and wherein each snapshot of DMA request entries is serviced in a window of time, and wherein the windows of time of the various snapshots are differnet amounts of time.

18. A method of allocating memory access bandwidth among a plurality of requesting entities in a digital camera, each of the requesting entities having a queue for storing DMA request entries, each DMA request entry being a request to perform an access of a memory integrated circuit in the digital camera, wherein each of the requesting entities has a tokens per snapshot (TPS) value, the method comprising: (a) selecting a snapshot of DMA request entries by selecting, for each queue, a number of DMA request entries based on the TPS value for the requesting entity associated with the queue; (b) servicing the DMA request entries in the snapshot in an order that reduces memory access overhead associated with performing the memory accesses requested by the DMA request entries in the snap shot; and (c) repeating steps (a) and (b).

19. The method of claim 18, wherein each tokens per snapshot (TPS) value is a number of tokens, and wherein a token represents one DMA request entry.

20. The method of claim 18, wherein each tokens per snapshot (TPS) value is an indication of an amount of data movement, and wherein each DMA request entry comprises an indication of an amount of data movement.

21. The method of claim 18, wherein each tokens per snapshot (TPS) value is an indication of an amount of time.

22. The method of claim 18, wherein one of the requesting entities is a compression engine.

23. The method of claim 18, wherein no DMA request entries are selected in (a) from a queue if there are no DMA request entries in the queue.

24. The method of claim 18, wherein the memory integrated circuit is a dynamic random access memory (DRAM) integrated circuit, and wherein the memory access overhead reduced in (b) includes overhead associated with performing a refresh operation on the DRAM integrated circuit.

Digital Camera Description

TECHNICAL FIELD

[0001] The present invention relates to a digital camera that has a plurality of functional parts that require access to a memory that has a limited memory access bandwidth.

BACKGROUND

[0002] Conventional consumer market digital cameras typically involve image processing circuitry as well as a separate memory integrated circuit. The memory integrated circuit may, for example, be a synchronous dynamic random access memory (SDRAM).

[0003] Images are captured by an image sensor. The image sensor outputs a stream of raw image information that is stored into the memory. In the case of video or a rapid sequence of still images, the flow of image information can be a fairly constant stream. At the same time that raw image information later in the stream is being stored into the memory, image information earlier in the stream is being read out of the memory for image processing by a digital image pipeline (DIP). The digital image pipeline may include several processing blocks. A first image processing block may be operating on a first part of the image stream, whereas a second image processing block is operating on a second part of the image stream. Each block may read image information from the memory, perform processing, and then write the resulting processed information back out to the memory. Several blocks of the digital image pipeline may therefore attempt to access the memory at the same time.

[0004] Not only can different blocks of the digital image pipeline require access to the memory, but there may be other blocks of functionality on the digital camera that require memory access as well. In one example, the digital camera includes a JPEG compression block. The JPEG compression block reads an image out of the memory, compresses the image, and then outputs a compressed version of the image and stores the compressed version back to the memory. The digital camera typically has a zoom engine that reads an image out of the memory, creates a smaller version of the image called a “thumbnail,” and then writes this thumbnail back to the memory. The digital camera typically has a display that the user can use to view the image about to be captured. The thumbnail may be read out from memory and may be supplied to the display for viewing. The digital camera may also have the ability to overlay an icon or text information over an image. An on-screen display (OSD) engine may read a background image out of the memory, superimpose the icon or text or other visual feature on top of the background image, and then write the composite image back out to memory for viewing on the camera’s display. A camera may also include a video encoder/decoder such as, for example, an MPEG2 codec. Image information may be read out of memory and sent through the MPEG2 codec. The resulting MPEG2 stream output by the MPEG2 codec may then be returned to memory.

[0005] The memory integrated circuit typically has a single access port that is used to write information into the memory and that is used to read information out of the memory. Due to the multiple different entities that need to read image information out of the memory integrated circuit, and the need to write image information into the memory integrated circuit, the access port of the memory integrated circuit is often times a throughput bottleneck in the camera. There is a limited amount of data that can be moved across the access port per unit time. In order for the camera to operate properly, the total amount of data to be moved either into or out of the memory by each of the accessing entities must total to a number less than the maximum memory access bandwidth of the memory integrated circuit.

[0006] Not only must the total memory access bandwidth required by all the accessing entities be less than the available memory access bandwidth available over the long term, but each of the accessing entities must not be made to wait too long to access the memory. The amount of time it takes to access the memory is sometimes referred to latency. If an accessing entity is made to wait too long, then operation of that entity may fail or be slowed or halted, thereby decreasing overall throughput of the camera. Some accessing entities may not be able to accommodate as much latency as other entities. The flow of video image information from the image sensor into the memory is one such process that typically can only tolerate a low amount of latency. If raw video image information being output from the image sensor cannot be stored within a certain amount of time, then it may be overwritten thereby resulting in the loss of raw image information. Other accessing entities, in contrast, can generally wait to access memory as long as over the long term those entities receive their required amount of access to the memory.

[0007] In one conventional digital camera, the total memory access bandwidth and latency issues are handled using an arbiter. Each of the accessing entities has its own dedicated DMA engine or engines. Within each accessing entity there may be sub-entities that access memory. When one of the accessing entities needs to access the memory, its DMA engine makes a request to the arbiter. If there is only one DMA engine making a request, then the request is granted and the accessing entity gains access to the memory. If there are multiple DMA engines making simultaneous requests, then one of the DMA engines is selected based on a strict priority or round robin arbitration scheme. If, for example, the DMA engine that moves raw image data from the image sensor into the memory is making a request at the same time that the zoom engine’s DMA engine is making a request, then the DMA engine for the raw image data will typically have its request granted and the zoom engine’s DMA engine will typically have to wait. To prevent latency problems, the system is designed so that so many high priority requests cannot be submitted in such a short period of time that the latency and bandwidth requirements of the lowest priority DMA engines are violated. Controlling when DMA engines can make requests and making sure that latency and throughput requirements of each of the requesting entities are not violated can give rise to difficult system design issues. If the system is changed, for example, then timing of the various DMA engines and the timing of their requests can change in complex ways. Reanalysis of the interplay between the various processing blocks of the system may be required. Flow shaping and scheduling are employed in the design of routers and switches in the networking and the telecommunications arts to handle bandwidth and latency issues. These techniques are, however, generally complex and tend to be expensive and cumbersome to implement. An inexpensive solution is desired that is suitable for use in a price-sensitive consumer market digital camera.

SUMMARY

[0008] A memory (for example, a synchronous dynamic read only memory–SDRAM) of a digital camera stores image information and has a single access port. Image information is both read out of the memory, and is written into the memory across this single access port. Memory access bandwidth on this access port is allocated among several requesters of the image information by assigning each requestor a “tokens per snapshot” (TPS) value. The tokens per snapshot value may, for example, be a number that indicates a number of DMA request entries. Each of the requesters has a DMA engine and a DMA request entry queue. If the requester wishes to access the memory, then a DMA request entry is pushed onto the DMA request entry queue of the requestor. This DMA request entry indicates, among other things, whether the access is to be a read or a write and the starting address to be accessed within the memory.

[0009] An arbiter block uses the TPS values of the various requesters to select DMA request entries off the various DMA request queues. If, for example, a given requestor is assigned a TPS value of two, then the arbiter block can select two DMA request entries off the queue (provided that there are two DMA entries on that queue). If there are less than two DMA request entries on the queue, then the arbiter block selects as many DMA entries as it can from the queue. In this way, the arbiter block selects DMA request entries from each queue. The resulting set of selected DMA request entries is called a “snapshot”.

[0010] Once the snapshot is selected, the arbiter block selects DMA request entries from the snapshot in an order for servicing such that memory access overhead in accessing the memory is reduced or minimized. Before a DMA request entry is selected for servicing, however, a “service time out value” (STOV) stored in association with each queue is checked. The service time out value is a value that indicates a time after which a DMA request entry on the queue should be serviced irrespective of the fact that servicing the DMA request entry immediately would result in an order of servicing DMA request entries that does not result in the minimal memory access overhead. Accordingly, the arbiter block checks a timer to see if any of the service time out values has elapsed. If a queue is determined to have timed out, then the next DMA request entry selected out of the snapshot for servicing is the oldest DMA request entry off that queue.

[0011] Each queue has a register in which a time out value (TOV) is stored. When a DMA request entry is selected for servicing by the arbiter block, the current time as indicated by the timer is added to the time out value (TOV). The resulting time becomes the service time out value (STOV) for the queue.

[0012] Once all the DMA request entries of the snapshot have been selected for servicing, then the arbiter block selects the next snapshot of DMA request entries. When a DMA request entry is selected for servicing by the arbiter block, the DMA engine associated with the DMA request entry issues either reads and/or writes to the SDRAM via a memory interface unit (MIU). The MIU translates the reads and/or writes into memory commands understood by the particular memory used. If possible, the MIU supplies any necessary memory commands such as activate commands, column read commands, column write commands and precharge commands to the memory at the same time that data is being transferred either into or out of the memory. Providing activate, column read, column write and precharge commands in this fashion reduces memory access overhead.

[0013] Both the tokens per snapshot (TPS) value and the time out (TOV) value for each queue can be written by a processor. Increasing the tokens per shapshot (TPS) value of a queue increases the amount of memory access bandwidth allocated to the requester associated with the queue relative to other requesters. Decreasing the time out (TOV) value of a queue reduces the maximum amount of time between successive servicings of DMA request entries of the queue and therefore reduces memory access latency for the associated requester.

[0014] Although a token indicates a DMA request entry in the example described above, a token may represent other quantities that allow the TPS values to be used to allocate memory access bandwidth among numerous requesters. A token may, for example, represent an amount of time that a requester is allowed to use the access port of the memory. A token may, for example, represent an amount of data that the DMA engine of the requester is allowed to move either into or out of the memory.

[0015] Although all the DMA request entries in the example described above correspond to an equal amount of data movement, this need not be the case. In one example, DMA request entries can indicate different amounts of data movement. The amounts of data movement for the DMA request entries on the bottom of a queue are summed to determine how many of the DMA request entries on the bottom of the queue amount to the tokens per snapshot (TPS) value for the queue. Alternatively, DMA entries can indicate different amounts of time such that the amounts of time for the DMA request entries on the bottom of a queue are summed to determine how many of the DMA request entries on the bottom of the queue amount to the tokens per snapshot (TPS) value for the queue.

[0016] Other embodiments and advantages are described in the detailed description below. This summary does not purport to define the invention. The invention is defined by the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, where like numerals indicate like components, illustrate embodiments of the invention.

[0018] FIG. 1 is a diagram of a digital camera in accordance with one embodiment of the present invention.

[0019] FIG. 2 is a simplified flowchart of the selection of DMA request entries for incorporation into a snapshot, and of the subsequent granting of the DMA request entries of the snapshot.

[0020] FIGS. 3, 6 and 7 illustrate the selection of two consecutive snapshots of DMA request entries.

[0021] FIG. 4 illustrates one possible organization of an SDRAM integrated circuit.

[0022] FIG. 5 is a simplified flowchart that illustrates how the granted DMA request entries pass through the MIU and are translated into memory commands by the MIU.

[0023] FIG. 8 illustrates a potential latency problem associated with the example of FIGS. 3, 6 and 7.

[0024] FIG. 9 illustrates how the latency problem illustrated in FIG. 8 may be solved in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION

[0025] Reference will now be made in detail to some embodiments of the invention, examples of which are illustrated in the accompanying drawings.

[0026] FIG. 1 is a simplified block diagram of a digital camera 1 in accordance with one embodiment of the present invention. Camera 1 includes image processing circuitry 2 and a memory integrated circuit 3. Memory integrated circuit 3 is, for example, a single Synchronous Dynamic Random Access Memory (SDRAM) integrated circuit that stores image information.

[0027] Image processing circuitry 2 includes a plurality of requesting entities. Each of these requesting entities includes a DMA engine. FIG. 1 shows a DMA engine 4 that transfers raw image information output from an image sensor into the SDRAM 3, a DMA engine 5 of a digital image pipeline, a DMA engine 6 of a zoom engine, a DMA engine 7 that transfers information to a display such as an LCD display, and a DMA engine 8 of a JPEG compression engine. Image processing circuitry 2 further includes memory interface unit (MIU) 9, an arbiter block 10, and a plurality of queues 11-15. If a DMA engine accesses SDRAM 3, it does so through MIU 9. If, for example, DMA engine 4 were to read from SDRAM 3, then DMA engine 4 would issue a series of reads to MIU 9 over parallel DMA bus 16, when allowed to do so by the arbiter. The reads would be buffered in a first-in-first-out memory 17 within MIU 9. MIU 9 would then translate the reads into memory commands understood by SDRAM 3. For example, before a memory location can be read from SDRAM 3, SDRAM 3 may require that the memory bank containing the desired location be “activated.” MIU 9 has the intelligence to know that the bank needs to be activated, and generates the necessary activate command that causes SDRAM 3 to activate the bank. The activate command, along with a row address for the subsequent memory access, is supplied onto a command bus 18 of SDRAM 3. After sending the activate command and the row address across command bus 18, MIU 9 sends an appropriate memory read command to SDRAM 3. A column address for the subsequent memory access is supplied along with the memory read command via command bus 18. SDRAM 3 returns the contents of the location indicated by the bank, row and column addresses to MIU 9 via a 16-bit wide parallel data bus 19. The command bus 18 and the data bus 19 together comprise a double data rate (DDR2) access port of SDRAM 3. All reads and writes to SDRAM 3 occur across this single access port. For more information on operation of the access port, see: JEDEC standard “DDR2 SDRAM Specification”, JESD79-2A, January 2004, published by the JEDEC Solid State Technology Association, 2500 Wilson Boulevard, Arlington, Va. 22201 (the subject matter of which is incorporated herein by reference).

[0028] Arbiter block 10 includes an arbiter 20, a timer 21, a plurality of tokens per snapshot (TPS) registers 22-26, and a plurality of time out value (TOV) registers 27-31. There is one TPS register and one TOV register for each of the DMA engines. A processor (not shown) that controls operation of the various blocks of the image processing circuitry 2 can write to the various TPS and TOV registers via a parallel bus 32. In one embodiment, the processor is an ARM processor and bus 32 is an AMBA compliant 32-bit data bus.

[0029] When camera 1 is operating, the various requesting entities through their respective DMA engines push DMA request entries onto their respective queues. In the illustration, a DMA request entry is pushed onto the top of the already-present DMA entries in a queue. Each DMA request entry is either a request to read an amount of data from SDRAM or a request to write an amount of data to SDRAM. The amount of data is, in the present example, sixteen bytes for both a read request entry and a write request entry. Each DMA read request entry includes the starting address of the first byte to be read from SDRAM, as well as an indicator bit that indicates that the request is a read request. Each DMA write request entry includes a starting address of the first location in SDRAM into which the data is to be written, as well as an indicator bit that indicates that the request is a write request.

[0030] In the present example, DMA engine 4 pushes write requests onto queue 11. DMA engine 4, when given authorization to do so by arbiter block 10, moves raw image information coming from the image sensor (not shown) of the camera into SDRAM 3. DMA engine 5 is the DMA engine for the digital imaging pipeline (DIP). DMA engine 5 pushes DMA read request entries onto queue 12. When given authorization to do so by arbiter block 10, DMA engine 5 reads raw image information out of SDRAM 3 and transfers the information to the DIP. The DIP processes the image information. DMA engine 5 then pushes DMA write request entries onto queue 12 to be given authorization to write the output of the DIP back into SDRAM 3. Similarly, DMA engine 6 of the zoom engine pushes both read requests and write requests onto queue 13. DMA engine 7 pushes read requests onto queue 14. DMA engine 8 of the JPEG engine pushes read requests and write requests onto queue 15. FIG. 1 shows each of the queues 11-15 containing DMA request entries. The “SA” designation in FIG. 1 indicates the “starting address” portion of the DMA request entry.

[0031] Arbiter block 10 determines which of the DMA request entries will be granted first and therefore which of the DMA engines will be able to access SDRAM 3 first. After arbiter block 10 has determined which DMA request entry will be granted, it returns a grant signal to the appropriate DMA engine by a dedicated acknowledge signal line. No grant signals are supplied to the other DMA engines by their respective grant lines. The grant lines are indicated by numerals 33-37. The DMA engine that received the grant then retrieves the oldest DMA request on its queue. The oldest DMA request entry in each queue in the illustration of FIG. 1 is DMA request entry that is on the bottom of the queue. The DMA engine services this oldest DMA request entry as set forth above by issuing reads and/or writes to MIU 9. MIU 9 converts the reads and/or writes into memory commands appropriate for SDRAM 3 in accordance with the JEDEC standard referenced above.

[0032] When a DMA engine has serviced the oldest DMA request by issuing reads and/or writes to MIU 9, then the DMA engine sends a done signal to arbiter block 10 via a dedicated done signal line. The done signal lines are indicated by numerals 38-42. When arbiter block 10 receives the done signal, arbiter block 10 determines the next DMA request entry that will be granted.

[0033] How arbiter block 10 determines which DMA request entry to grant is as follows and as set forth in FIG. 2. First (step 100 of FIG. 2), arbiter block 10 uses the tokens per snapshot (TPS) values for each of the queues to determine the number of DMA request entries to select out of each DMA queue. In the present example, a token per snapshot (TPS) number is a number in units of DMA request entries. A token per snapshot (TPS) number of two, for example, indicates two DMA request entries.

[0034] The set of selected DMA request entries is referred to here as a “snapshot” of DMA request entries. All the DMA request entries in the snapshot will be granted before any other DMA request entries are granted. Once a first snapshot of entries is granted, then a second snapshot of entries can be selected. Only after the first snapshot of DMA request entries is granted can the second snapshot of DMA request entries be granted. This process repeats. If a first DMA engine is to be allocated twice the amount of memory access bandwidth as a second DMA engine, then the first DMA engine should be allocated twice as many DMA entries per snapshot on average as the second DMA engine receives. The tokens per snapshot (TPS) value for this first DMA engine will therefore be set to be twice as large as the tokens per snapshot (TPS) value for the second DMA engine.

[0035] FIG. 3 illustrates an example in which a first snapshot of DMA request entries is selected. The tokens per snapshot (TPS) value for each of the DMA engines 4-8 is 1, 4, 2, 2, and 6, respectively. There is no DMA request entry in queue 11. No DMA request entry is therefore selected from queue 11 even though the tokens per snapshot (TPS1) value for queue 11 is one. The first four DMA entries of queue 12 are selected, the first two DMA entries of queue 13 are selected, the first two DMA entries of queue 14 are selected, and the first three DMA entries of queue 15 are selected. Only three DMA entries of queue 15 are selected even though the TPS value for DMA engine 8 is six. This is because queue 15 only contains three DMA entries. The line 200 in FIG. 3 represents the DMA entries selected.

[0036] Once the first snapshot of DMA entries is selected, arbiter 20 selects a DMA request entry for granting (step 101 of FIG. 2) as follows. When a DMA request entry for a particular DMA engine has been granted (for example, as indicated by receipt of a done signal from the DMA engine), then a service time out value STOV (not shown) for the DMA engine is reset to be the current time as maintained by timer 21 plus the time out value TOV stored in the TOV register corresponding to the DMA engine. If the DMA engine does not have its next DMA request entry granted by the time the service time out value STOV arrives (as indicated by timer 21), then arbiter 20 selects the next DMA request entry to be granted to be the oldest DMA request entry for that DMA engine. Accordingly, arbiter 20 checks to see if any of the DMA queues have timed out (step 101 of FIG. 2).

[0037] If a DMA queue has timed out, then the next DMA entry for the timed out DMA queue is the next DMA request to be granted. If no DMA queue has timed out, then arbiter 20 selects the next DMA request entry (step 101 of FIG. 2) in the snapshot for granting so as to minimize SDRAM access overhead. Ways of minimizing SDRAM access overhead are explained in further detail below. If all the DMA request entries in the snapshot have not been granted (step 104 of FIG. 2), then the process of granting DMA request entries (step 101) continues until all DMA request entries in the snapshot have been granted. Once all the DMA request entries of the snapshot have been granted, processing returns to step 100 and a subsequent snapshot of DMA request entries is selected.

[0038] The order in which DMA request entries are granted within a snapshot is chosen such that memory access overhead is reduced or minimized. Certain orders of granting DMA request entries may result in more memory access overhead than others. Arbiter 20 has intelligence to be able to select an order of DMA request entry granting that reduces or minimizes this overhead for the particular type of memory being accessed. How this is done is described in connection with FIG. 4.

[0039] FIG. 4 illustrates a typical SDRAM integrated circuit 30. SDRAM 30 is a 64 megabyte SDRAM, having four banks 31-34 of memory cells. Each bank has 16 megabytes of memory cells. Each bank is made up of many 1 k byte pages of memory cells. If a page in a first bank is being accessed, and then the next access is an access to the same page in the same bank, then the SDRAM integrated circuit does not require that the bank be either precharged or activated (unless there was some other intervening non-access related event, such as refresh). The second access can follow the first access without any special precharge command or any special activate command having to be sent to the SDRAM before the second access can be made.

[0040] If, however, the first access is of a page within a bank and the next access is of another page in the same bank, then the second page must be activated before the second access can be made. A activate command is sent to SDRAM 3 via command bus 18. Only after the second page has been activated, can the second access be performed. Accordingly, there is a memory access bandwidth penalty to performing this order of memory accesses.

[0041] If a first access is of a page within a first bank and the next access is of a page in another bank, then there may or may not be a memory access bandwidth penalty. Before the second access can be made, the second page must be activated. The SDRAM can, however, be instructed to perform this activation at an earlier time such that the activation to read or write delay is satisfied. If the activate command can be sent to the SDRAM over the command bus 18 (overlapping with the data transfer for some prior read or write access) prior to the activation to read or write time, then the memory access bandwidth penalty associated with this order of accessing is minimized. If, on the other hand, the activate command for the second access cannot be sent to the SDRAM early enough to satisfy the activation to read or write delay, then this delays the second access and constitutes a memory access bandwidth penalty. Arbiter 20 knows how to order the granting of the DMA entries within first snapshot 200 (see FIG. 3) such that the memory access bandwidth penalty associated with accessing SDRAM 3 is reduced or minimized.

[0042] In one embodiment, arbiter 20 examines the starting addresses of all the DMA entries of the snap shot while the DMA entries of the snapshot are still in their various queues. Arbiter 20 can remove any DMA entry in a queue and pass that DMA entry to its corresponding DMA engine even if the DMA entry is not the bottom-most (the oldest) DMA entry on that queue, provided that the DMA entry removed is within the snapshot. This allows arbiter 20 to remove the DMA entries of the snapshot and pass them to the DMA engines in any order such that the memory access bandwidth penalty is reduced or minimized.

[0043] FIG. 5 is a flowchart that illustrates how granted DMA request entries are converted into commands that cause the memory accesses to occur. First (step 102 of FIG. 5), a DMA engine that receives a grant via its grant line issues a memory read or a memory write across DMA bus 16 as if the DMA engine were reading or writing from MIU 9. The memory reads and writes from the various DMA engines accumulate in the FIFO 17 within MIU 9. Next (step 103 of FIG. 5), MIU 9 examines the stream of memory reads and memory writes in FIFO 17 and pipelines any needed precharge and activate commands with prior memory accesses if it is possible to do so. Arbiter 20 and MIU 9 therefore work together to deal with the idiosyncrasies of the particular SDRAM used in order to reduce memory access overhead. MIU 9 converts the memory reads and memory writes in FIFO 17 into appropriate memory commands that are supplied to SDRAM 3 across command bus 18. MIU 9 also supplies data to SDRAM 3 via data bus 19 for memory writes and receives data from SDRAM 3 via data bus 19 for memory reads.

[0044] FIG. 6 illustrates DMA request entries being pushed onto queues 11 and 15 immediately after the first snapshot 200 of DMA entries of FIG. 3 has been selected. DMA request entry 201 is a new DMA request entry pushed onto queue 11. In this example, there are also new DMA request entries pushed onto queue 15. As set forth above, all entries of the first snapshot are granted before any of these newly pushed DMA request entries is selected for incorporation into a snapshot.

[0045] FIG. 7 illustrates a subsequent step in which a second snapshot 202 of DMA request entries is taken. Again, arbiter 20 uses the tokens per snapshot (TPS) values in registers 27-31 to determine how many DMA request entries, if present, to select from each queue. The tokens per snapshot value TPS1 for DMA engine 4 is one, so the newly added DMA entry 201 is selected for incorporation into the second snapshot. The tokens per snapshot value TPS2 for DMA engine 5 is four, but there are only two DMA entries on queue 12. Only two DMA entries from queue 12 are therefore selected. The tokens per snapshot TPS5 for DMA engine 8 is six, and there are six DMA entries on queue 15, so six DMA entries are selected from queue 15. The selected DMA request entries are shown enclosed in line 202 in FIG. 7.

[0046] FIG. 8 illustrates a latency issue that can appear in the situation of FIGS. 3, 6 and 7. The maximum amount of time to grant a DMA entry from queue 11 is approximately two snapshots worth of memory access time. This occurs in the situation in which a DMA request entry such as DMA request entry 201 arrives shortly after the selection of the entries for the first snapshot, and where the DMA request entry 201 ends up to be the last DMA request entry granted in the second snapshot. FIG. 8 illustrates such a situation.

[0047] If the latency associated with the situation of FIG. 8 cannot be tolerated by DMA engine 4, then the time out value TOV1 for queue 11 is set such that DMA queue 11 will time out at an earlier time. DMA engine 4 that transfers raw image information from the image sensor and places that raw image information into SDRAM 3 may, for example, only be able to tolerate a relatively small amount of latency when it tries to transfer data to SDRAM 3. If DMA engine 4 is made to wait too long when it is trying to write raw image information into SDRAM 3, then the raw image information may be overwritten thereby resulting in a loss of raw image information. This latency problem is to be avoided.

[0048] FIG. 9 illustrates an example in which the time out value TOV1 is set to be smaller than the amount of time it takes for the granting of eleven DMA requests (the eleven DMA requests of the first snapshot). Accordingly, because an entry off the bottom of queue 11 has not been granted for this amount of time, DMA queue 11 times out during the granting of the first snapshot of DMA request entries. When the second snapshot of DMA request entries is selected, and selection of which DMA request entries in the second snapshot to grant begins, the DMA request entry 201 is selected for granting before other DMA request entries of the second snapshot the queues of which have not timed out. Note that DMA request entry 201 in FIG. 9 is granted at the beginning of the granting of the thirteen DMA request entries of the second snapshot, rather than at the end of the granting of the thirteen DMA request entries of the second snapshot at illustrated in FIG. 8.

[0049] Although the present invention has been described in connection with certain specific embodiments for instructional purposes, the present invention is not limited thereto. The technique of selecting a snapshot of DMA request entries is not limited to use in digital cameras, but rather is a general-purpose technique usable to control access to a memory. Although the entities making requests to access the memory may be DMA engines in some embodiments, other types of entities can be requesting entities. Processors and specific-purpose state machines can be requesting entities. Although the invention is described in connection with controlling access to one memory integrated circuit, the invention is usable to control access to multiple integrated circuits. The memory to which access is controlled need not be a separate integrated circuit from the arbiter circuitry, but rather both the arbiter circuitry and the memory can be integrated on the same integrated circuit. Although bus 16 is illustrated as a bus wherein a single group of bus conductors carry information from a selected one of the DMA engines 4-8 to MIU 9, this need not be the case. DMA bus 16 need not have conductors over which signals pass in a bidirectional fashion. For example, the outputs of DMA engines 4-8 can be supplied to the data input leads of a multiplexer and the select input leads of the multiplexer can be controlled by the arbiter to couple a selected one of the DMA engines 4-8 to MIU 9. Although the technique of using snapshots to allocate memory access bandwidth is described above in connection with a digital camera, the technique is applicable in any system involving a memory. Accordingly, various modifications, adaptations, and combinations of various features of the described embodiments can be practiced without departing from the scope of the invention as set forth in the claims.

The present invention relates to a remote controller of a vehicle with a built-in digital camera. The remote controller of the present invention is provided with a built-in digital camera so that it can be used to record the actual scenes of a car accident as images. The built-in digital camera in the remote controller of the present invention comprises a base plate, which comprises a liquid crystal display, a shutter, a lens, a control unit, a memory unit, and an input/output port.

Digital Camera Claims

1. A remote controller of a vehicle with a built-in digital camera: (a) a base plate which comprises a liquid crystal display, a shutter, a lens, a control unit, and a memory; and (b) an input/output port, wherein a digital camera is arranged in a preset manner both inside and outside of a case for said remote controller.

2. The remote controller according to claim 1, wherein said shutter is disposed at an upper front end of said case for said remote controller along with a door locking button and a unlocking button while said liquid crystal display is disposed at a lower front end of said case for said remote controller.

3. The remote controller of a vehicle with a built-in digital camera according to claim 1, wherein said lens is disposed at an upper rear end of said case for said remote controller and said input/output port is mounted at one end of said case for said remote controller.

4. The remote controller according to claim 1, wherein said case for said remote controller is further provided with an on/off switch of said digital camera in a preset position.

5. A digital camera comprising: a vehicle remote controller; and a display, a shutter, and a lens disposed on said vehicle remote controller.

6. The digital camera of claim 5 further comprising a memory disposed within said vehicle remote controller.

7. The digital camera of claim 5 further comprising an activation switch disposed on said vehicle remote controller.

8. The digital camera of claim 5 further comprising an input/output port disposed on said vehicle remote controller.

9. An apparatus for taking pictures, comprising: a vehicle remote controller; and a digital camera built into said vehicle remote controller.

10. The apparatus of claim 9, wherein said digital camera comprises a shutter, a lens, a memory, and an input/output port.

11. The apparatus of claim 10, wherein said digital camera comprises a display disposed on said vehicle remote controller.

12. The apparatus of claim 11, wherein said digital camera comprises an activation switch disposed on said vehicle remote controller.

Digital Camera Description

CROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims priority from Korean Patent Application No. 2004-51871, filed on Jul. 5, 2004, which is hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

[0002] The present invention relates to a vehicle remote controller with a built-in digital camera. More particularly, this invention relates to a vehicle remote controller with a built-in digital camera, which can be used to record the scenes of car accidents as images.

BACKGROUND OF THE INVENTION

[0003] Vehicle accidents are no longer rare incidents to be observed in our daily lives, and they often result in having disputes between people being involved in the accidents because of the difficulties of retaining the actual spot of the accident which may help to distinguish between right and wrong. Therefore, some drivers carry cameras including Polaroid cameras in the glove box of their cars as a way to obtain a solid on-the-spot evidence in case of an accident. However, for people who normally do not carry cameras, they are at risk in becoming innocent victims. Therefore, there has been a long-felt need for drivers to have a reliable means to preserve the accident scene as it is.

SUMMARY OF THE INVENTION

[0004] The present invention provides a vehicle remote controller with a built-in digital camera to record the actual scenes from a car accident as images, while it can be still used under normal situations for remote start-up or locking/unlocking of a car door from a distance. The images recorded by the digital camera can be very helpful for use as evidence covering on-the-spot scenes.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] The aforementioned aspect and other features of the present invention will be explained in the following detailed description, taken in conjunction with the accompanying drawings, wherein:

[0006] FIG. 1 is a perspective view of a remote controller with a built-in digital camera according to an embodiment of the present invention;

[0007] FIG. 2 is a front view of a remote controller with a built-in digital camera according to an embodiment of the present invention;

[0008] FIG. 3 is a rear view of a remote controller with a built-in digital camera according to an embodiment of the present invention; and

[0009] FIG. 4 is a side view of a remote controller with a built-in digital camera according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention provides a vehicle remote controller with a built-in digital camera, wherein the digital camera comprising:

[0011] (a) a base plate which comprises a liquid crystal display, a shutter, a lens, a control unit, and a memory; and

[0012] (b) an input/output port,

[0013] wherein the digital camera is arranged in a preset manner both inside and outside of the case of the remote controller.

[0014] In a preferred embodiment of the present invention, the shutter in the remote controller is disposed at an upper front end along with the door locking and unlocking buttons while the liquid crystal display is disposed at a lower front end of the remote controller case.

[0015] In a more preferred embodiment of the present invention, the lens is disposed at an upper rear end of the remote controller case while the input/output port is mounted at one end of the remote controller case.

[0016] In another preferred embodiment of the present invention, the remote controller case is further provided with an on/off switch for a digital camera in a preset position.

[0017] The present invention is described in greater detail with reference to the accompanying drawings, but they should not be construed as limiting the scope of this invention. FIG. 1 shows a perspective view of a remote controller with a built-in digital camera according to an embodiment of the present invention. FIG. 2 is a front view of the same. FIG. 3 is a rear view of the same.

[0018] The present invention is particularly advantageous in that a built-in digital camera is provided in a vehicle remote controller so that on-the-spot scenes of any unexpected vehicle accidents can be recorded as images in the event of such accidents, and they can be used as evidence to resolve disputes that may result from the accidents.

[0019] Generally, a vehicle remote controller is provided with a button for engine start-up 12 and buttons for door locking and unlocking 14 and 16, respectively, along with an antenna 18 disposed at an upper front end to exchange signals for a remotely controlled engine start-up. In recent years, mobile phones have been provided with built-in cameras, and, in this invention, each component of the digital camera is disposed in a preset manner of arrangement.

[0020] As stated above, the above digital camera comprises a base plate which comprises a liquid crystal display, a shutter, a lens, a control unit, a memory unit, and an input/output port. The digital camera is arranged in a preset manner so that the liquid crystal display, the shutter, the lens, and the input/output port are exposed to the outside while the control unit and memory unit are disposed inside of the remote controller case. A vehicle remote controller with a built-in digital camera of the present invention can be prepared by disposing each of the digital components both inside and outside of the vehicle remote controller in a preset manner. That is, door locking and unlocking buttons 14 and 16 are disposed at the front side of the case 10 of the remote controller and a shutter 20 is disposed in an area between the above two buttons. Further, the liquid crystal display 22 is disposed at the lower front end of the remote controller case 10, and the lens 24 is disposed at the upper rear end of the remote controller case 10 as shown in FIG. 3.

[0021] Additionally, an on/off switch 26 for the digital camera is disposed at a preset position of the remote controller case 10 so that the digital camera can be “on” only when the camera is to perform its presumed function. The input/output port that transmits information obtained as images to other external devices, such as a PC, a camcorder, a printer, etc., is disposed at one end of the remote controller case 10 as shown in FIG. 4. Therefore, the remote controller of the present invention can perform its original functions of engine start-ups and locking/unlocking doors from a distance under normal situations while it can serve an additional important function of taking pictures of on-the-spot car accident scenes and storing them as image files, when needed.

[0022] That is, by going through with the simple steps of putting the switch 26 of the digital camera in the “on” position, directing the lens toward the object of the car accident during which the digital camera concurrently takes pictures of the spots of the car accident by pushing the shutter 20 while viewing through the display 22, the images of these pictures can be stored and/or printed by connecting to other external devices such as a PC, a camcorder, a printer, etc., and used as valuable information to settle any related disputes should they ever happen.

[0023] While the foregoing description represent various embodiments of the present invention, it will be appreciated that the foregoing description should not be deemed limiting since additions, variations, modifications and substitutions may be made without departing from the spirit and scope of the present invention. It will be clear to one of skill in the art that the present invention may be embodied in other forms, structures, arrangements, and proportions and may use other elements, materials and components. The present disclosed embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims and not limited to the foregoing description.

A digital multimedia playing and recording storage device with a function of a digital camera, includes a CPU, an HD for storing data processed by the CPU, an I/O module connected with the CPU for transmitting data from the CPU, a video capturing module connected with the CPU for capturing video data, a function key module for selectively controlling function status of the CPU, an LCD driving module for displaying video data processed by the CPU, an audio module connected with the CPU for capturing or playing audio data, and a power supply module for supplying power to the above modules.

Digital Camera Claims

1. A digital multimedia playing and recording storage device with a function of a digital camera, comprising: a CPU; an HD, for storing data processed by the CPU; an I/O module, connected with the CPU for transmitting data from the CPU; a video capturing module, connected with the CPU for capturing video data; a function key module, for selectively controlling function status of the CPU; an LCD driving module, for displaying video data processed by the CPU; an audio module, connected with the CPU for capturing or playing audio data; and a power supply module, for supplying power to the above modules.

2. The digital multimedia playing and recording storage device with a function of a digital camera as claimed in claim 1, wherein the video capturing module includes a lens and a light sensitive component.

3. The digital multimedia playing and recording storage device with a function of a digital camera as claimed in claim 1, wherein the I/O module includes an I/O port, a wireless transmission device and an AV output port.

4. The digital multimedia playing and recording storage device with a function of a digital camera as claimed in claim 3, wherein the I/O port is connectable with a personal computer, an AV player and so on.

5. The digital multimedia playing and recording storage device with a function of a digital camera as claimed in claim 3, wherein the I/O port is a USB interface.

6. The digital multimedia playing and recording storage device with a function of a digital camera as claimed in claim 1, wherein the audio module includes a speaker and a microphone.

7. The digital multimedia playing and recording storage device with a function of a digital camera as claimed in claim 1, wherein the CPU can compress and convert video data captured by the video capturing module and audio data captured by the audio module to MPEG format with high compression ratio and high quality.

Digital Camera Description

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a storage device, and particularly to a digital multimedia playing and recording storage device with a function of a digital camera.

[0003] 2. Prior Art

[0004] As development of information technology, people may take with more and more digital products. For example, an office worker may take with a portable data storage disk, a digital camera, a recording pen, a multimedia player and so on. Each kind of digital products provides a specific function.

[0005] However, it is often inconvenient for a user to take with many digital products for providing different functions. For example, as a popular digital product, a digital camera is assembled with a memory card for storing data of pictures. Capacity of a conventional memory card is usually 128 MB or 256 MB which can only store a few of pictures. Therefore, a user has to take with several memory cards for a larger capacity. However, the memory card is quite expensive. Furthermore, different kinds of memory cards, such as a compact flash (CF) card, a smart media (SM) card, a memory stick (MS) card and so on, are incompatible.

[0006] Thus, it is required to design a digital multifunctional product which is bulky in capacity, portable and plugable and play.

SUMMARY OF THE INVENTION

[0007] Accordingly, an object of the present invention is to provide a digital multimedia playing and recording storage device with a function of a digital camera, which is bulky in capacity and provides functions of a digital camera, a multimedia player and a recording pen for convenience to use.

[0008] Another object of the present invention is to provide a digital multimedia playing and recording storage device with a function of a digital camera for being portable.

[0009] Another object of the present invention is to provide a digital multimedia playing and recording storage device with a function of a digital camera, which is combined with a digital camera, a multimedia player, a USB interface, and a wireless transmission module, and which uses a hard disk (HD) as a storage module for storing data from the digital camera or the multimedia player or through the USB interface or the wireless transmission module, thereby providing a small, light and portable storage device with high capacity.

[0010] Another object of the present invention is to provide a digital multimedia playing and recording storage device with a function of a digital camera having a USB interface for providing a function of plug and play.

[0011] To achieve the above-mentioned objects, a digital multimedia playing and recording storage device with a function of a digital camera in accordance with the present invention includes a CPU, an HD for storing data processed by the CPU, an I/O module connected with the CPU for transmitting data from the CPU, a video capturing module connected with the CPU for capturing video data, a function key module for selectively controlling function status of the CPU, an LCD driving module for displaying video data processed by the CPU, an audio module connected with the CPU for capturing or playing audio data, and a power supply module for supplying power to the above modules.

[0012] Other objects, advantages and novel features of the present invention will be drawn from the following detailed embodiment of the present invention with attached drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIG. 1 is a schematic chart showing a digital multimedia playing and recording storage device with a function of a digital camera of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0014] Referring to FIG. 1, a digital multimedia playing and recording storage device with a function of a digital camera of the present invention includes a central processing unit (CPU) 10, a hard disk (HD) 12 for storing data processed by the CPU 10, an input/output (I/O) module 14 connected with the CPU 10 for transmitting the data of the CPU 10, a power supply module 16, a video capturing module 18 connected with the CPU 10 for capturing video data, a function key module 20 for selectively controlling function status of the CPU 10, a liquid crystal display (LCD) driving module 22 for displaying video data processed by the CPU 10, and an audio module 24 connected with the CPU 10. The power supply module 16 supplies power to the above modules. The video capturing module 18 includes a lens 181 and a light sensitive component 182. The audio module 24 includes a speaker 241 for audio output and a microphone 242 for audio input.

[0015] The I/O module 14 is used for transmitting video data or other data and includes a wireless transmission device 141 for wireless transmission, an audio and video (AV) output port 142, and an I/O port 143 which may be a USB interface for providing a function of plug and play. The wireless transmission device 141 may be a Bluetooth data transmission device or an infrared data transmission device. The I/O port 143 may be connected with a personal computer, an AV player and so on. The CPU 10 may transmit data through the I/O port 143.

[0016] In use of the digital multimedia playing and recording storage device of the present invention, one of functions of the digital multimedia playing and recording storage device may be selected through the function key module 20. For example, when the AV recording function is selected, the CPU 10 can receive video data captured by the lens 181 and the light sensitive component 182 of the video capturing module 18 and audio data input by the microphone 241 of the audio module 24. Then the CPU 10 compresses the received AV data and converts the received AV data to MPEG format with high compression ratio and high quality and then stores the AV data in the HD 12.

[0017] Of cause, the CPU 10 may be configured to only receive the video data from the video capturing module 18 for achieving a video recording function, or to only receive the audio data from the microphone 241 for achieving an audio recording function.

[0018] After the CPU 10 stores the AV data in the HD 12, a video playing function may be selected through the function key module 20 to turn on an LCD 221 of the LCD driving module 22 and the speaker 242 of the audio module 24 thereby playing the AV data. Of cause, AV data prestored in the HD 12 can also be played by the CPU 10 through the LCD 221 of the LCD driving module 22 and the speaker 242.

[0019] Of cause, audio data, such as MP3, stored in the HD 12 may be read by the CPU 10 and then played through the speaker 242 of the audio module 24 thereby achieving a function of a music player.

[0020] Selection of the above functions of the present invention is made through the function key module 20 to control the CPU 10. For example, a video recording function to receive video data captured by the video capturing module 18, or an audio recording or playing function to receive audio data from the microphone 241 or play audio data through the speaker 242, or an AV recording function to receive video data from the video capturing module 18 and audio data from the microphone 241 of the audio module 24, or a multimedia playing function to drive the LCD driving module 22, or a function of a portable data storage device to transmit data through the I/O port 143 or the wireless transmission device 141, may be selected respectively. The HD 12 is a mini HD with high capacity and so the digital multimedia playing and recording storage device of the present invention can store quite a lot of AV data.

[0021] As mentioned above, the digital multimedia playing and recording storage device with a function of a digital camera of the present invention has functions of a digital camera, a multimedia player, a portable data storage device, a recording pen and a USB interface, and uses the HD 12 with high capacity to store data captured by the digital camera, the multimedia player, the recording pen, or transmitted from external devices through the USB interface. Thus, the digital multimedia playing and recording storage device with a function of a digital camera of the present invention is small, light and bulky in capacity and so is convenient to use.

[0022] It is understood that the invention may be embodied in other forms without departing from the spirit thereof. Thus, the present examples and embodiments are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein.