JP2007221685A - Digital camera and control method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain a RAW data printing that has been impossible heretofore, when a digital camera is connected directly to a printer. <P>SOLUTION: Within the digital camera, RAW data are reproduced, resized, rotated and the like and image data are transferred to a printer, after being converted into JPEG images. Furthermore, if a printing size is relatively small, JPEG image data for preview, generated together with RAW, are transmitted to the printer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a direct print system that transmits an image to be printed from an imaging apparatus capable of recording RAW image data to a printer.

  Conventionally, when printing image data recorded and held in an imaging apparatus such as a digital camera, there are generally two formats. One is a digital camera direct print in which a digital camera and a printer are directly connected using a cable such as a USB, an image selected by the digital camera is transmitted to the printer, and printing is performed. The other is card direct printing in which a memory card in which image data is recorded is inserted into a memory card slot of a printer, and an image to be printed is selected by an operation button of the printer and printed.

  FIG. 6 shows a standard form of a conventional digital camera direct print.

  Reference numeral 110 denotes a storage medium such as a memory card in which image data taken by the digital camera 1000 is recorded. Image data read from the storage medium 110 is stored in the image buffer 111. The stored image is decompressed from JPEG compression and displayed on the display device 115. When image printing is designated from the user interface 113, the image transmission unit 112 reads the image designated for printing from the image buffer 111 and transmits it to the printing apparatus 200. At this time, if the setting for performing the automatic image correction process is made by the user interface 113, the camera system controller 120 transmits a signal for enabling automatic correction to the system controller 210 of the printing apparatus 200.

The image data transmitted from the image transmission device 112 is received by the image receiving unit 201 and stored in the image buffer 202. The stored image is decompressed by the image decompression unit 203, and if automatic image correction is enabled, the image is corrected, the print image processing unit 204 performs print output processing, and the printing device 205 performs printing. .
JP 2004-13349 A

  However, in the conventional digital camera direct print system, the printer does not support images other than JPEG, for example, uncompressed images such as RAW image data, and images other than JPEG compression cannot be handled. For this reason, the RAW image data shot in the RAW recording mode of the digital camera cannot be printed unless it is developed with a computer and converted into a JPEG image.

In order to solve the above problems, an imaging apparatus according to the present invention has the following configuration. That is,
A digital camera that can record RAW image data and communicates with a printer to transmit an image to be printed to the printer, and digitally converts a signal output from the image sensor to generate RAW image data Generation means, display means for displaying an image, recording means for recording RAW image data generated by the image generation means on a storage medium, and development for displaying the RAW image data on the display means Preview image generation means for performing preview processing and resizing processing to generate preview image data; determination means for determining whether RAW image data can be printed in the printer; and RAW image data in accordance with a print instruction from a user Or control means for transmitting preview image data to the printer, the control means Depending on the determination result in serial determination means, and determines whether to transmit either the RAW image data or the preview image data.

  In the first embodiment of the present invention, when printing RAW data taken by a digital camera, the image signal is transferred to the printer after the RAW data is reproduced, resized, rotated, etc. in the digital camera. Further, when the print size is relatively small, the printing is performed using the preview JPEG signal generated together with the RAW.

  With the above configuration, when the digital camera and the printer are directly connected, RAW data printing, which was impossible in the past, can be performed. Further, when the print size is small, a JPEG image for preview is used, so that high-speed printing is possible.

  In the second embodiment of the present invention, the signal processing IC of the digital camera is built in the printer, and the processing block is used together when the RGB image signal photographed by the digital camera is converted into the CMY signal for printing. Take. With this configuration, not only JPEG but also RAW data can be printed at high speed. Further, when RAW data is transferred to the printer, the RAW data is resized on the digital camera side according to the output resolution and output size of the printer and then transferred. As a result, even in a digital camera having a large number of pixels, transfer does not take time and the memory capacity on the printer side can be reduced.

(First embodiment)
FIG. 1 is a schematic block diagram of a direct printing system process according to the first embodiment of the present invention. This direct print system includes a digital camera 10 and a printer 20. The operation will be described below with reference to the drawings.

  The operation of the digital camera 10 is performed under control (not shown), and the camera system controller 120 reads a program code from a memory (not shown) and performs control and processing based on the read program. Similarly, the operation of the printer 20 is also performed under the control of a printer system controller (not shown). The printer system controller reads a program code from a memory (not shown) and performs control and processing based on the read program.

(photograph)
An electrical signal output from the image sensor 1001 such as a CCD or CMOS is converted into a digital image signal by an A / D converter 1002 and recorded as an image signal in a memory 1003 such as a DRAM. When the RAW shooting mode is selected by the user, the image signal temporarily recorded in the memory 1003 is recorded as RAW image data. At this time, the RAW image data and the JPEG image data for preview (described later) are recorded as one image data file on an external recording medium 1017 such as a memory card.

  Here, RAW image data is image data obtained by simply digitizing an electrical signal obtained from an image sensor without generating image data in consideration of parameters such as white balance and saturation, and pixel data of a plurality of colors. Are two-dimensionally arranged in a predetermined order.

  Next, a method for generating JPEG image data for preview for displaying RAW image data on a display screen (not shown) and previewing the image will be described.

  The image signal temporarily recorded in the memory 1003 is subjected to development processing in 1004 to 1016 and converted into JPEG image data. First, black drawing is performed by an OB (optical black) circuit 1004, and WB processing is performed by a WB (white balance) circuit 1005. The image signal after the WB processing is subjected to color interpolation for each color by the color interpolation circuit 1006 and converted to a UV signal by the color conversion circuit 1007. Thereafter, the CSUP circuit 1008 suppresses the colors of the low luminance and high luminance portions. On the other hand, a luminance signal is created by the luminance interpolation circuit 1009 for the image signal after WB, and edge enhancement is performed by the edge enhancement circuit 1010. Next, the color conversion circuit 1011 creates an RGB signal using the output UV signal of the CSUP circuit 1008 and the output Y signal of the edge enhancement circuit circuit 1010, and the gamma circuit 1012 performs gamma correction. The RGB signal after the gamma correction is converted again to a YUV signal by the color conversion circuit 1013 and resized to an image size suitable for preview by the resize rotation circuit 1014. In the case of a digital camera equipped with a posture sensor, the image is rotated 90 degrees in the case of vertical position shooting based on the output of the posture sensor. The output signal of the resize rotation circuit 1014 is subjected to fine color correction by the 3DLUT circuit 1015, converted to a JPEG signal by the JPEG conversion circuit 1016, and recorded in the memory 1003.

(Print)
Next, an operation when the user prints a RAW image using the UI (user interface) of the digital camera 10 will be described.

  When printing of an image is instructed on a UI (not shown) such as a display screen or operation buttons of the digital camera 10, RAW image data of the image instructed to print from the external recording medium 1017 and JPEG image data for preview are stored in the memory 1003. Is read out.

  The digital camera 10 receives information related to the output resolution and output size of the printer 20 from the communication unit 2019 of the connected printer 20, and the size of image data required for printing according to the output resolution and output size of the printer 20 Is determined. For example, an image of about 2 Mpixel is required for printing the L plate at 300 dpi, and an image of about 5 Mpixel is required for printing the A4 plate at 300 dpi. Here, it is assumed that information regarding the output size is received from the printer 20, but information input by the user through the UI of the digital camera 10 may be used for the output size.

  In the direct print system according to the present invention, the number of pixels of the preview JPEG image that has been subjected to the development process is compared with the number of pixels necessary for the determined printing. As a result of the comparison, if the number of pixels of the preview JPEG image is large, the preview JPEG image read from the external storage medium 1017 is transferred from the communication unit 1019 to the printer 20 and printed.

  When the number of pixels of the preview JPEG image is smaller than the number of pixels necessary for printing, the RAW image data is subjected to development processing and resizing processing, and the print JPEG image data converted into the JPEG signal is transferred from the communication unit 1019 to the printer 20. Sent to.

  Conversion from the RAW image data to the JPRG image data for printing is performed by the signal processing IC from 1004 to 1016. Since the operation from the OB circuit 1004 to the color conversion circuit 1013 is processed in the same operation flow as that for creating the preview JPEG signal, description thereof is omitted. The output YUV signal of the color conversion circuit 1013 is resized by the resizing circuit 1014 so that the number of horizontal and vertical pixels is necessary for printing. The resized signal is subjected to fine color correction by the 3DLUT circuit 1015, converted to a JPEG signal by the JPEG conversion circuit 1016, and recorded in the memory 1003. The print JPEG image data recorded in the memory 1003 is transmitted from the communication unit 1019 to the printer 20.

  In the printer 20, the communication unit 2019 receives the print target JPEG image data transmitted from the communication unit 1019 of the digital camera 10. The received JPEG image data is recorded in the memory 2003. The image data recorded in the memory 2003 is transferred to the JPEG decompression circuit 2022 of the signal processing circuit mounted on the printer 20 and converted into a YUV signal. The YUV signal is transferred to the color conversion circuit 2011 to become an RGB signal, which is corrected by the gamma circuit 2012 with a curve having an inverse gamma characteristic as shown in FIG. 3-3001, and converted into a linear RGB signal. The linear RGB signal is converted again into a YUV signal by the color conversion circuit 2013 and enlarged or reduced by the resizing circuit 2014 to a resolution corresponding to the output size of the printer. The resized YUV signal is converted into a CMY signal by the 3DLUT circuit 2015. The 3DLUT circuit here is a known three-dimensional lookup table conversion, which is used to perform RGB → CMY conversion. Finally, the output CMY signal of the 3DLUT circuit is transferred to the print engine 2021, and printing is performed.

  With the above configuration, it is possible to reduce the image size to be transferred to the printer while ensuring the image size necessary for printing, so that it is possible to transfer at high speed, and the image buffer required on the printer side can be reduced. is there.

  With the above configuration, when the digital camera and the printer are directly connected, it is possible to print RAW image data, which was impossible in the past. When the image size to be printed is small in a digital camera that records RAW image data and preview JPEG image data as one image data file, the preview JPEG image data is transmitted to the printer. Therefore, since no new JPEG image is generated, the time required for processing until image transmission is reduced as compared with the conventional case, and the printing processing time can be shortened. Further, even if the RAW image data and the JPEG image data are not recorded as one image data file, the developed image data created for the preview may be transmitted to the printer.

(Second embodiment)
FIG. 2 is a schematic block diagram of a direct printing system process according to the second embodiment of the present invention.

  In the second embodiment, a direct print system when a printer 21 capable of developing a RAW image and a digital camera 11 are connected for communication will be described.

  2 having the same reference numerals as those in FIG. 1 are the same as those in the first embodiment, and the description thereof is omitted.

(photograph)
Since the processing flow is the same as that of the first embodiment, description thereof is omitted.

(Print)
An operation when the user prints a RAW image using the UI of the digital camera 11 will be described.

  When printing of an image is instructed on the UI (not shown) of the digital camera 11, RAW image data of the image instructed to be printed and JPEG image data for preview are read from the external recording medium 1017 to the memory 1003.

  The digital camera 10 receives information on the output resolution and output size of the printer 20 from the communication unit 2019 of the connected printer 20. The camera system controller 120 determines the size of image data necessary for printing in accordance with the output resolution of the printer 20 and the print size designated for printing. As in the first embodiment, information input by the user through the UI of the digital camera 10 may be used for the output size. In addition, information regarding whether or not development processing of RAW image data has a function or whether development processing is possible is acquired from a connected printer.

  If it is determined from the information received from the printer that a printer capable of developing RAW image data is connected, preview JPEG image data or print JPEG image data is created as in the first embodiment. To the printer.

  If it is determined that a printer capable of developing RAW image data as shown in FIG. 2 is connected, the digital camera 11 transmits the RAW image data to the printer 21.

  An operation flow when the RAW image data is transmitted from the digital camera 11 to the printer 21 will be described in detail.

  First, as in the first embodiment, the digital camera 11 determines the size of image data required for printing according to the received output resolution and output size. The size required for printing is compared with the size of the RAW image data to be printed read from the external recording medium 1017. As a result of the comparison, if the size required for printing is larger, the RAW image data read from the external recording medium 1017 is transmitted from the communication unit 1019 to the printer 21.

  If the size of the RAW image data is larger, the RAW image data is sent to the RAW resize circuit 1018. RAW image data is resized by the RAW resize circuit 1018 (described in detail later), and the resized RAW image data is transmitted from the communication unit 1019 to the printer 21.

When the printer 21 receives the RAW image data,
In the direct print system according to the present invention, the number of pixels of a preview JPEG image that has been subjected to development processing is compared with the number of pixels necessary for the determined printing. If the number of pixels of the preview JPEG image is large, the preview JPEG image read from the external storage medium 1017 is transferred from the communication unit 1019 to the printer 20 and printed.

  When the number of pixels of the preview JPEG image is smaller than the number of pixels necessary for printing, the RAW image data is subjected to development processing and resizing processing, and the print JPEG image data converted into the JPEG signal is transferred from the communication unit 1019 to the printer 20. Sent to.

  When the printer 21 receives the RAW image data in the communication unit, the printer 21 transfers the image data to the memory 2003 and stores it. This RAW image data is transferred to the OB circuit 2004. Blacking is performed in 2004, and white balance is performed in the WB circuit 2005. Thereafter, a UV signal is generated through a color interpolation circuit 2006, a color conversion circuit 2007, and a CSUP circuit 2008. On the other hand, a Y signal is generated from the image signal after WB through the luminance interpolation circuit 2009 and the edge enhancement circuit 2010. These YUV signals are converted into RGB signals by the color conversion circuit 2011, and the gamma circuit 2012 is converted by linear setting (FIG. 3-3003) where the input signal and the output signal are the same. The output RGB signal of the gamma circuit is converted into a YUV signal by the color conversion circuit 2013, is input to the 3DLUT circuit 2015 via the resize rotation circuit 2014, and is converted into a CMY signal. The CMY signal is transferred to the print engine and printing is performed.

  Note that the processes 2004 to 2015 of the printer are the same as the processes 1004 to 1015 of the digital camera. Therefore, if the circuits 1004 to 1015 of the digital camera are made into one signal processing IC and this signal processing IC is built in the printer, the processing block is used together when the RAW image data is converted into a CMY signal for printing in the printer. can do. It is also possible to print RAW data. Further, it is not necessary to separately create an IC for converting JPEG image data or RAW image data into CMY data, which is advantageous in terms of cost.

  Hereinafter, the processing operation of the RAW resizing circuit 1018 will be described with reference to FIGS. The color separation circuit 4001 separates the color of the input RAW signal. 5001 in FIG. 5 is a diagram visually showing RAW data, and is separated into four plane signals (5002 to 5005) of RG1G2B by the color separation circuit. Next, the color signals of the four planes after color separation are input to the pixel interpolation circuit 4002, and each pixel having no value (a pixel having a value of 0) is interpolated. In this interpolation calculation, an interpolation plane signal such as 5006 to 5009 is obtained using a two-dimensional filter having the characteristics 5010 in FIG. The signal band of the interpolated RG1G2B signal is limited by the horizontal low-pass filter 4003 and the vertical low-pass filter 4004. This is because, for example, a low-pass filter having characteristics such as 5011 in FIG. 5 is used to suppress the aliasing phenomenon due to the subsequent resampling. The band-limited RG1G2B signal is resized by general-purpose linear interpolation or cubic interpolation calculation in the resample circuit 4005. Next, as shown in FIG. 5012, the single-chip circuit 4006 converts the 4-plane signal into a single resized RAW image signal.

  As described above, when transferring RAW data to the printer, the RAW data is resized on the digital camera side according to the output resolution and output size of the printer and then transferred. For this reason, even in a digital camera having a large number of pixels, transfer does not take time, and the memory capacity on the printer side can be reduced.

1 is a schematic block diagram of a direct print system according to a first embodiment. Schematic block diagram of a direct printing system of the second embodiment Gamma curve Raw resize processing simple flow RAW resize processing conceptual diagram Schematic diagram of conventional print block processing block

Explanation of symbols

1001, 2001 Image sensor 1002, 2002 A / D conversion circuit 1003, 2003 Memory 1004, 2004 OB circuit 1005, 2005 WB circuit 1006, 2006 Color interpolation circuit 1007, 2007 YUVtoRGB color conversion circuit 1011, 2011 RGBtoYUV color conversion circuit 1013, 2013 YUV to JPEG color conversion circuit 1008, 2008 CSUP circuit (color suppression)
1009, 2009 Luminance interpolation circuit 1010, 2010 Edge enhancement circuit 1012, 2012 Gamma conversion circuit 1014, 2014 Resize rotation circuit 1015, 2015 3DLUT circuit 1016 JPEG conversion circuit 1017, 2017 External storage medium 1018 RAW resize circuit 2021 Print engine 4001 Color separation circuit 4002 Pixel interpolation circuit 4003, 4004 Low pass filter 4005 Resample circuit 4006 Single plate circuit 100 Imaging device 110 Storage medium 111 Image buffer memory 112 Image transmission means 113 User interface 114 Image expansion means 115 Display means 116 Image compression means 120 Camera system controller DESCRIPTION OF SYMBOLS 200 Printing apparatus 201 Image receiving means 202 Image buffer memory 203 Image expansion means 04 printer image processing unit 205 printing unit 210 the printer system controller 220 printer image correcting means

Claims (5)

A digital camera capable of recording RAW image data and transmitting an image to be printed to the printer by communicating with the printer,
Image generation means for digitally converting a signal output from the image sensor and generating RAW image data;
Display means for displaying an image;
Recording means for recording RAW image data generated by the image generating means on a storage medium;
Preview image generation means for generating preview image data by subjecting the RAW image data to development processing and resizing processing for display on the display means;
Determining means for determining whether the printer can print RAW image data;
Control means for transmitting RAW image data or preview image data to the printer in response to a print instruction from a user;
The digital camera according to claim 1, wherein the control unit determines whether to transmit RAW image data or preview image data according to a determination result of the determination unit.   The digital camera according to claim 1, wherein the control means determines an image to be transmitted to the printer according to an image size required for printing. Furthermore, it has a resizing means for resizing the RAW image data,
When the determination unit determines that the printer is capable of printing RAW image data, the control unit outputs the RAW image data resized by the resize unit according to the image size required for printing. A digital camera characterized by being transmitted to.   The control unit determines that the printer cannot print RAW image data by the determining unit, and the preview image data generated by the preview image generating unit is larger than an image size required for printing. The digital camera according to claim 1, wherein the preview image data is transmitted to the printer.   The resizing means performs color separation of raw image data in which pixel data of a plurality of colors are two-dimensionally arranged in a predetermined order to generate color signal data of each color, and performs interpolation processing on the color separated color signal data , Resize each color signal data, then convert the color signal data into a single plate and generate resized RAW image data.

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