JP2005175978A - Image processing system of digital camera directly connectable to printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To convert image data of a digital camera side into data capable of drawing out the performance owned by a printer to the maximum and print the converted data. <P>SOLUTION: In the image processing system of the digital camera which is connectable directly to the printer, if a first color space of image data photographed by the digital camera side is smaller than a second color space to which the printer can correspond when a photographed image is printed by the printer, re-development is performed in an optimum color space matching the color space of the printer from the accumulated digital data before image processing, the image is transferred to the printer, and the image is printed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a digital camera and a printer that can be directly connected to the digital camera, and more particularly to a color space of image data when an image is directly transferred from the digital camera to the printer for printing.

  Conventionally, even when the color space that can be input on the printer side is wider than the color space of the image output by the digital camera, printing is performed only in the color space output by the digital camera, and it is not possible to demonstrate the full capabilities of the printer. there were.

  For example, as shown in FIG. 7, when a digital camera 41 and a printer 43 are directly connected by a serial cable 42 such as IEEE1394 or USB, and an image of the digital camera 41 is printed by the printer 43, a jpeg image can be printed by the printer. The data is converted to YCbCr and sent.

  Alternatively, if there is sufficient memory on the printer 43 side, the jpeg file is sent and printing is performed using the printer function.

Further, when adjusting the image of the digital camera or changing the color space, a personal computer 54 is required between the digital camera 51 and the printer 57 as shown in FIG. And print on the printer 57 via the printer cable 56.
Japanese Laid-Open Patent Publication No. 10-173833

  However, in the above conventional example, as shown in FIG. 6, even if the printer has a color gamut wider than the color space such as sRGB30, for example, AdobeRGB31, the input data is mapped in the color space of sRGB30. The color gamut could not be used.

  Even if the printer can input a wider color space than sRGB30, if the image output from the digital camera is the sRGB30 color space, the color space of the digital camera image is converted from sRGB30 to a wider color space. However, the lost gradation cannot be reproduced only by the color space conversion.

  An object of the present invention is to solve such problems, and an object of the present invention is to convert image data on a digital camera side into data that can draw out the power of a printer to the maximum and print it.

  In order to solve the above problems, the present invention is configured as follows.

  That is, the image processing system of the present invention includes an image sensor that converts an optical image into an electrical signal, a unit that outputs a signal from the image sensor as an image signal, a unit that converts the image signal into digital data, Image processing means for image processing the digitized image data, means for storing both the digitized image data and the image data after image processing, and the image processed An image processing system comprising: a digital camera having means for displaying image data; and a printer capable of printing the image processed image data on a paper medium that can be directly connected to the digital camera. When printing on the printer, the first color space of the image data taken on the digital camera side can be input to the printer. When the color space is smaller than 2, the image data is re-developed from the accumulated digital data before image processing in an optimal color space that matches the color space of the printer, the image is transferred to the printer, and printing is performed. .

  Further, the digitized image data is RAW data before image processing, and the image data after the image processing is image data converted into YCbCr such as jpeg or the like, and images with three RGB planes. It is characterized by being data.

  The first color space is, for example, sRGB, and the second color space is a color space such as AdobeRGB or NTSC.

  The re-developed image data is stored in a recording medium as another image file.

  According to the present invention, in a digital camera image processing system that can be directly connected to a printer, if the color space of the printer is wider than the color space of the data of the digital camera, the gradation in the wide color space inherent in the image data is eliminated. Therefore, it is possible to print an image having a higher gradation than that obtained by forcibly using the wide color gamut of the printer by simply increasing the data saturation.

BEST MODE FOR CARRYING OUT THE INVENTION

  Examples of the present invention will be described below.

  Hereinafter, an image processing system for a digital camera according to a first embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is a block diagram of a digital camera according to an embodiment of the present invention. The light passing through the photographing lens 1 passes through the infrared cut filter 2 and the optical LPF 3 and forms an image on the image pickup device 4 (hereinafter referred to as CCD).

  Sensors based on photodiodes are arranged in a plane on the light receiving surface of the CCD 4. For each sensor, one color, for example, R (red), G (green), B (blue) primary color filters. Are arranged in a predetermined arrangement. For example, a configuration in which one image is assigned to each image sensor using a plurality of the image sensors is also possible.

  The light focused on the CCD 4 is converted into an amount of electric charge corresponding to the amount of incident light in each sensor. The signal generated by the timing generator 16 is supplied to the horizontal drive driver 17 and the vertical drive driver 18 to drive the CCD 4, transmit charges accumulated in the sensor, and are sequentially converted into voltage signals. The converted voltage signal is sampled by correlated double sampling 5 (hereinafter referred to as CDS) and converted to a digital signal by the A / D converter 6.

  The image data converted into the digital signal is input to the IC 7, enters the WB circuit 7 a for calculating data for white balance, and is temporarily stored in the memory 1 of 8. The data stored in the memory 1 is again input to the IC 7, and in this embodiment, four image processes are performed.

  First, the image data converted into a digital signal is converted into lossless compressed RAW data in a lossless compression circuit 7d that performs lossless compression (reversible compression) as it is, and sent to the CPU bus 10.

  Further, the image data converted into the digital signal is down-sampled by averaging the RAW data in the block as shown in FIG. 5, for example, and decimating it, so that the RAW data is converted into a thumbnail image smaller than the original image size. Thinning-out processing is performed by the thumbnail circuit 7 c and it is sent to the CPU bus 10.

  Further, since the image data converted into the digital signal is not an image with three RGB planes as it is, the image processing is performed in the image processing 7b to perform color interpolation and the like, and the image is displayed on the LCD 12. Therefore, the thumbnail image is thinned out for display and sent to the CPU bus 10.

  Finally, the image data converted into YCbCr in the image processing circuit 7b for jpeg compression is raster-block converted in the memory 2 of 9, and is subjected to jpeg compression in the jpeg compression circuit 7e and sent to the CPU bus 10. It is done.

  Here, the image processing performed by the image processing circuit 7b will be described in more detail.

  An outline of image processing in the image processing circuit 7b will be described with reference to a block diagram in FIG.

  The white balance coefficient calculated by the CPU 15 is preliminarily applied to the white balance 7b1 based on the data calculated by the WB circuit 7b in order to calculate the white balance in advance.

  Alternatively, the input image data is multiplied by a coefficient of a set white balance (for example, daylight, tungsten, fluorescent lamp, etc.) in the white balance 7b1.

  The white balance image data is color-interpolated at 7b2 for color interpolation, and an RGB3 plane is created from the pattern data in which RGB are arranged in a grid as shown in FIG.

  Next, the image data having the RGB3 planes is subjected to color optimization in the masking processing circuit 7b3 by, for example, 3 × 3 matrix calculation (Equation 1) and the like, and gamma conversion is performed in the gamma conversion circuit 7b4. .

R '= m11xR + m12xG + m13xB
G '= m21xR + m22xG + m23xB (Formula 1)
B '= m31xR + m32xG + m33xB
Finally, the gamma-converted image data is converted from RGB signals into YCbCr luminance and color difference component signals for jpeg compression.

  On the other hand, the gamma-converted image data is obtained by applying a two-dimensional LPF (for example, a 5 × 5 two-dimensional LPF as shown in FIG. 4) to the color-interpolated RGB3 plane as shown in FIG. The obtained image is further thinned to be converted into a thumbnail image for LCD display.

  The lossless compressed data, RAW thumbnail data, LCD display thumbnail data, and jpeg data, which are the four image data sent from the CPU bus 10, are respectively stored in the memory 3 of 11 and converted into respective file formats.

  Among them, the thumbnail data for LCD display is sent again to the CPU bus 10, sent to the video encoder circuit 7 f in the IC 7, and displayed on the LCD 12.

  Lossless compressed data and jpeg data are sent to the I / F circuit 13 and stored in the storage medium 14. A series of these operations is performed by pressing the release switch 19 of the CPU 15 once.

  Next, when a thumbnail image for LCD display is displayed on the LCD, while pressing the menu button 20, the dial 24 is turned to select a print from the menu.

  Next, the number of sheets to be printed is determined by turning the dial 24 while pressing the number-of-prints button 21, and the data is read from the recording medium 14 to the CPUBUS 10 via the I / F 13 by pressing the print OK button 22. 11 memory 3. The image data stored in the memory 3 is converted into printer data, for example, YCbCr, and is output to the CPUBUS 10 again, and is output from the USB port 28 to the printer 29 via the I / F 27. .

  Therefore, if the printer 29 side supports input of a color space wider than sRGB, the image data read from the recording medium 14 is read not through the jpeg data but through the RAW data before development via the I / F 13, and the CPU BUS10. And stored in the memory 3 of 11. The stored RAW data is decompressed and sent to the IC 7 via the CPU BUS 10 for the IC 7 to redevelop again.

  In the IC 7, in 7 b 3 in the development processing block 7 B, the color space corresponding to the printer 29, for example, the matrix for Adobe RGB is set again instead of the matrix for the sRGB color space, and redevelopment is performed. The re-developed image is output again to the CPU BUS 10 and stored in the memory 3 of 11.

  Next, the developed image data stored in the memory 3 of 11 is converted into data for the printer 29, for example, YCbCr, and is output to the CPU BUS 10 again, via the I / F 27, the USB port 28 To the printer 29.

  Therefore, the above-described configuration and processing can provide a print that draws out the performance of the printer.

  Next, a more detailed description will be given using the flowchart of FIG.

  The process starts when the print OK button 22 is pressed from the print menu.

  First, the camera and printer acquire information on each other's color space by communication (S1). Next, when the printer side supports an extended color space wider than sRGB (S2), it is determined whether the developed image is a color space wider than sRGB (S3). If the developed image is sRGB, it is determined whether RAW + jpeg photography has been performed (S4). In the case of shooting only jpeg, it is converted into print data, for example, YCbCr (S5), and output to the printer (S6). The printer performs printing based on the data obtained from the camera.

  If the image was shot with RAW + jpeg in S4, the RAW data is read from the recording medium and decompressed (S7). The decompressed RAW data is sent to the IC 7 and is most developed using, for example, a matrix coefficient for AdobeRGB (S8).

  Next, the most developed image data is converted into printer data such as YCbCr (S9) and output to the printer (S10).

  Finally, it is determined whether or not an image re-developed for a printer is to be recorded (S11). When an image with a changed color space is to be recorded, it is stored in a recording medium (S12).

  By realizing the above image processing system, it is possible to perform printing that draws out the performance of the printer.

1 is a block diagram of a digital camera according to a first embodiment of the present invention. It is a block diagram of the detail of the block regarding the part of FIG. It is a conceptual diagram which shows the interpolation method of the image processing of the digital camera which concerns on 1st Example of this invention. It is a conceptual diagram which shows the thinning-out method of the image processing of the digital camera which concerns on 1st Example of this invention. It is a conceptual diagram which shows the thinning-out method of the image processing of the digital camera which concerns on 1st Example of this invention. It is a chromaticity diagram showing the color space of the image of the digital camera according to the first embodiment of the present invention. It is a block diagram which shows the structure of this invention which concerns on 1st Example of this invention. The flowchart of the image processing of the digital camera which concerns on embodiment of this invention The block diagram which shows the prior art example of this invention which concerns on embodiment of this invention

Explanation of symbols

4 Image sensor 7 Image processing IC
8 memory 1
12 LCD (display means)
14 Recording medium 15 CPU
30 sRGB color space 31 AdobeRGB color space

Claims (4)

  An image sensor that converts an optical image into an electrical signal, a means for outputting a signal from the image sensor as an image signal, a means for converting the image signal into digital data, and image processing of the digitized image data A digital camera having image processing means for storing, storage means for storing both the digitized image data and the image data after image processing, and means for displaying the image processed image data; In an image processing system with a printer capable of printing the image processed image data on a paper medium that can be directly connected to the digital camera, when the photographed image is printed on the printer, the digital camera takes the image If the first color space of the obtained image data is narrower than the second color space that can be input by the printer, the stored image The image processing system characterized by perform redevelopment in optimum color space to suit the physical previous digital data into a color space of the printer performs printing by transferring the images to the printer.   The digitized image data is RAW data before image processing, and the image data after the image processing is image data converted into YCbCr such as jpeg or image data including three planes of RGB. The image processing system according to claim 1.   2. The image processing system according to claim 1, wherein the first color space is sRGB or the like, and the second color space is a color space such as AdobeRGB or NTSC.   An image processing system, wherein the re-developed image data is stored in a recording medium as another image file.

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