JP2011082784A - Image processing apparatus, image processing method, and image processing program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make colors to be printed out close to colors to be displayed on a picture on the basis of arbitrary image data. <P>SOLUTION: An image processing apparatus includes: a printing color characteristic acquisition means for acquiring printing color characteristics including the color gamut of colors to be printed out; a means for acquiring image data; an operation means for accepting operation for adjusting colors of the image data within an adjustment range; an adjustment range-setting means for setting the adjustment range in which the colors of the image data are settled in the color gamut of the colors to be printed out, on the basis of the printing color characteristics; and a color adjustment means for adjusting the colors of the image data according to the accepted operation. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image processing apparatus, an image processing method, and an image processing program, and more particularly to color management for printing.

  Color management that matches the colors of images displayed by a plurality of devices is known (see Patent Document 1). In color management between two devices having different color characteristics, at least one of gradation value compression, expansion, and saturation occurs during color space conversion. In CMM (Color Management Module), a color space conversion method can be specified by specifying a rendering indent.

JP2009-126100

  However, when the gamuts (color gamuts) of a plurality of devices are different, all the colors output from the respective devices cannot be completely matched with the conventional technology. For example, if "absolute" is specified as the rendering indent, the colors match in the overlapping gamut range, but the gradation value is saturated outside the color gamut. Therefore, the rich color of the image displayed on the display based on the image data is greatly changed to a different color that the user did not expect in the printed image even though the image is printed based on the same image data. Sometimes. In addition, if “perception” is specified as the rendering indent, the gradation value does not saturate, but it is necessary to compress or expand the gradation value, so even if the color is in the color gamut, a different color that the user did not expect. Will change greatly.

  The present invention was created in view of such a problem, and an object of the present invention is to prevent the color displayed by printing based on arbitrary image data from greatly differing from the color displayed on the screen. I will.

  (1) An image processing apparatus for achieving the above object includes a print color characteristic acquisition unit that acquires a print color characteristic including a color gamut of a print display color, a unit that acquires image data, and the image data in an adjustment range. An operation means for accepting an operation for adjusting the color of the image, an adjustment range setting means for setting the adjustment range in which the color of the image data falls within a color gamut of the print display color based on the print color characteristics, and the accepted Color adjusting means for adjusting the color of the image data in accordance with an operation.

  Here, the print color characteristic is definition information that enables at least the range of colors that can be displayed by printing, that is, the color gamut of the print display color, to be uniquely specified by coordinates (combination of gradation values). This is information in which the color gamut of the display color is defined through a device-independent color space such as CIE L * a * b * and CIE XYZ. Generally, the color gamut of the print display color is narrower than the color gamut of the color displayed on the screen. Therefore, in order to match the color displayed on the screen with the color displayed on the screen based on the color data indicating the color of the pixel, it is necessary that the color that cannot be printed is not designated by the color data. According to the present invention, since the color of the image data cannot be adjusted in a range that does not fall within the color gamut of the print display color, the screen display color of the image data and the print display color are not matched by adjusting the color. it can. Therefore, according to the present invention, it is possible to prevent the color printed and displayed based on arbitrary image data from greatly differing from the color displayed on the screen.

(2) In the image processing apparatus for achieving the above object, the adjustment range setting means may analyze the image data and set the adjustment range based on an analysis result and the print color characteristic.
According to the present invention, since the adjustment range can be set for each image data, it is possible to adjust the color by effectively using the color gamut of the print display color. For example, the adjustment range of image data with low saturation can be made wider than the adjustment range of image data with high saturation.

  Note that the function of each means described in the claims is realized by a hardware resource whose function is specified by the configuration itself, a hardware resource whose function is specified by a program, or a combination thereof. The functions of these means are not limited to those realized by hardware resources that are physically independent of each other. Furthermore, the present invention can also be realized as an image processing method, an image processing program, or an image processing program recording medium. Of course, the recording medium for the computer program may be a magnetic recording medium, a magneto-optical recording medium, or any recording medium that will be developed in the future.

The block diagram concerning embodiment of this invention. The figure which shows GUI concerning embodiment of this invention. The flowchart concerning embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in the following order with reference to the accompanying drawings. In addition, the same code | symbol is attached | subjected to the corresponding component in each figure, and the overlapping description is abbreviate | omitted.

1. 1. First embodiment 1-1. 1. Overview A first embodiment of the present invention is an image processing apparatus including a GUI (Graphical User Interface) that accepts an operation for adjusting the color of image data in a range where the color of the image data falls within the color gamut of the print display color.

1-2. Configuration The configuration of an image processing apparatus 1 as a first embodiment of the present invention is shown in FIG. The image processing apparatus 1 includes a personal computer (PC) including a CPU 14, a ROM 15, a RAM 16, a display control unit 11, a hard disk device (HDD) 12, an interface (I / F) 13, and the like. A keyboard 32, a mouse 33 and a display 31 for operating the image processing apparatus 1 are connected to the image processing apparatus 1. An image processing program P1 for causing the PC to function as the image processing apparatus 1 is installed in the HDD 12. The image processing program P1 is loaded into the RAM 16, and the CPU 14 executes the GUI module P11, the adjustment range setting module P12, the color adjustment module P13, and the like that constitute the image processing program P1, whereby various functions of the image processing apparatus 1 are performed. Realized.

  The GUI module P11 is a program module for displaying the editing window 20 shown in FIG. 2A on the screen of the display 31. The editing window 20 constitutes a GUI that receives an operation for adjusting the color of the image data. The editing window 20 is provided with a slider for adjusting the color of the image data and an image display area 24 in which an image based on the image data is displayed. The slider 21 is a slider for adjusting the saturation. The slider 22 is a slider for adjusting the brightness. The slider 23 is a slider for adjusting the contrast. In the vicinity of the sliders 21, 22, and 23, status bars 21a, 22a, and 23a indicating the respective adjustment ranges are displayed. The sliders 21, 22, and 23 can be operated within a range indicated by both ends of the status bars 21a, 22a, and 23a. That is, outside the range indicated by the both ends of the status bars 21a, 22a, and 23a, user operations on the sliders 21, 22, and 23 are not accepted. When the operation range of the sliders 21, 22, and 23 whose color is adjusted within the color gamut of the print display color is displayed by the status bars 21 a, 22 a, and 23 a, the color is adjusted for the purpose of screen display, and the purpose is print display. It is possible to make the user recognize that the adjustment range differs depending on the color adjustment. In the image display area 24, an image is displayed based on image data whose color is adjusted according to the positions of the sliders 21, 22, and 23. Data for displaying the editing window 20 is generated by the GUI module P11 and written in the display area of the RAM 16. The display control unit 11 displays an image on the screen of the display 31 based on the data written in the display area of the RAM 15.

  The adjustment range setting module P12 is a program module for setting a color adjustment range in which the color of the image data D2 falls within the color gamut of the print display color based on the print color characteristics. Specifically, when the adjustment range setting module P12 is executed, the saturation of the image data D2 is analyzed for each hue of the ink of the printer, and the sliders 21, 22, 23 are based on the analysis result and the print color characteristic D1. The color adjustment range made according to the operation is set.

The print color characteristic D1 is information that defines the color (print display color) expressed on the print medium by the inkjet printer 3 by the gradation value of CIE L * a * b * or CIE XYZ which is a PCS (Profile Connection Space). It is. Specifically, a look-up table in which each color of 28 ^{× 3} colors represented on the print medium by printing is associated with a gradation value of 12-bit depth of each channel of CIE XYZ representing the same color is set as the print color characteristic D1. To do. The print color characteristic D1 may be provided to the user as a part of the image processing program P1, downloaded from a server computer connected to the image processing apparatus 1 via the Internet, or input to the image processing apparatus 1 from a removable memory. You may do it. When adopting a configuration in which the user inputs arbitrary print color characteristics to the image processing apparatus 1, an operation for registering the print color characteristics in the image processing apparatus 1 is received via the GUI. The data format of the print color characteristic D1 is arbitrary, but it may be in accordance with the data format of the ICC profile.

  The print color characteristic is definition information unique to a specific printer. Therefore, in order to make the image processing program P1 correspond to an arbitrary printer, the image processing program P1 needs a function for setting print color characteristics specific to the printer on which the image data is printed. Such a function may be accepted by a GUI menu operation using the mouse 33 or the keyboard 32, or may be automatically set by the image processing program P1 according to the installation of the printer driver.

  The color gamut that can be printed by the printer 3 is represented by print color characteristics, and is generally narrower than the color gamuts of sRGB and Adobe RGB. Colors outside the color gamut represented by the print color characteristic D1 of the printer 3 when the image data D2 generated in the color space defined on the assumption of the color gamut of the display (color gamut of the screen display color) such as sRGB or Adobe RGB , Even if the color is displayed on the screen of the display 31, there are colors that cannot be printed and displayed by the printer 3. Therefore, the adjustment range setting module P12 sets the color adjustment range corresponding to the operation of the sliders 21, 22, and 23 so that the adjustment that causes such a color is not performed.

  The color adjustment module P13 is a program module for adjusting the color of the image data D2 in accordance with the operation received by the editing window 20. Specifically, when the sliders 21, 22, and 23 are operated, the color adjustment module P13 is executed, so that the saturation, brightness, and contrast of the image data are adjusted according to the positions of the sliders 21, 22, and 23. Is done.

1-3. Image Processing Method FIG. 3 is a flowchart showing an image processing method executed on the image data D2 acquired by the image processing apparatus 1 that executes the image processing program P1.
First, the image processing apparatus 1 reads the image data D2 selected by the GUI operation from the digital camera 2 or the HDD 12 into the RAM 16, and analyzes the saturation of the image data D2 for each hue (S100). Specifically, the pixel with the highest saturation for each ink hue of the printer 3 is detected from the image data D2, and the saturation of the detected pixel is acquired. The ink hue of the printer 3 may be specified based on the print color characteristic D1, or may be determined in advance in the image processing program P1 assuming a general printer.

  Next, the image processing apparatus 1 sets a conversion function according to the positions of the sliders 21, 22, and 23 based on the analysis result of the image data D <b> 2 and the print color characteristic D <b> 1 and sets the operation range of the sliders 21, 22, and 23. Set (S101). Specifically, first, the color with the highest saturation is specified for each ink hue of the printer 3 based on the print color characteristic D1. Then, a color conversion function that sets the highest saturation color of the printer 3 as the limit color of the conversion result is set. The color adjustment range varies depending on what conversion function is set. The color conversion function is a function of the positions of the sliders 21, 22, and 23. Further, since the color conversion function is set based on the analysis result of the image data D2, it differs for each image data D2. Specifically, for example, when the image data D2 is generated by photographing close-up flowers with high saturation, and when the image data D2 is generated by photographing a distant view of a rocky mountain with low saturation. Then, the correspondence between the position of the slider 21 for adjusting the saturation and the coefficient multiplied by the saturation of the image data D2 is different. The positions of both ends of the status bars 21a, 22a, and 23a indicating the operation ranges of the sliders 21, 22, and 23 are set according to the color gamut of the print display color and the screen display color.

  Next, the image processing apparatus 1 causes the display 31 to display the editing window 20 in which the sliders 21, 22, and 23 in which the operation ranges are set and the status bars 21a, 22a, and 23a in which the lengths are set are arranged (S102). . At this time, since the operation ranges of the sliders 21, 22, and 23 indicated by the status bars 21a, 22a, and 23a are set based on the analysis result of the image data D2, the image data as shown in FIGS. 2A and 2B. Different for each D2. For example, assume that the difference between the display gamut and the print gamut is small in the cyan hue and large in the magenta hue. In this case, the width for reducing the operation range of the slider 21 displayed for the image data D2 containing only the cyan hue color is small according to the print color gamut (that is, the status bar 21a becomes long), The width by which the operation range of the slider 21 displayed for the image data D2 containing only the magenta hue color is reduced according to the print color gamut (that is, the status bar 21a is shortened).

  Next, when the sliders 21, 22, and 23 are operated, the image processing apparatus 1 adjusts the color of the image data D2 according to the positions of the sliders 21, 22, and 23 (S103).

  When receiving a print instruction from the user, the image processing apparatus 1 converts color data representing the color of each pixel of the image data into print data for printing by the printer 3 based on the print color characteristic D1. At this time, print data to be printed by the printer 3 with the same color as the color displayed on the display 31 within the color gamut of the print display color is generated. On the other hand, if the color displayed on the display 31 includes a color outside the print display color gamut, the color is replaced with another color, and print data to be printed by the printer 3 is generated.

  According to the first embodiment described above, the color adjustment range corresponding to the operation range of the sliders 21, 22, and 23 is set according to the color gamut of the print display color defined in the print color characteristic D 1. The color of the image data cannot be adjusted within a range that does not fall within the display color gamut. Therefore, it is possible to prevent the screen display color of the image data from being inconsistent with the print display color by adjusting the color by operating the sliders 21, 22 and 23. That is, according to the first embodiment described above, the color displayed on the screen and the color displayed on the screen can be brought close to each other based on arbitrary image data.

  In general, a display is used because of an error based on an effective digit when converting color data representing the color of each pixel of image data into print data for printing by the printer 3 or an error due to individual differences of the printer 3. It is almost impossible to cause the printer 3 to print with exactly the same color as that displayed on the printer 31. However, the “same color” in this specification is a term including a color having an error range which is not strictly the same color. Further, “different colors” in the present specification are words that mean different colors beyond the range of error.

3. Other Embodiments The technical scope of the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the scope of the present invention.
For example, in the above embodiment, in order to be able to simultaneously recognize the operation range of the slider corresponding to the color gamut of the print display color and the operation range of the slider corresponding to the color gamut of the screen display color, Although it is displayed every time, the status bar may not be displayed, and the operation range of the slider may not be set according to the print color gamut. In other words, the configuration on the GUI screen that accepts color adjustment operations is fixed regardless of the print color gamut, and the internal process for GUI operations is set according to the print color gamut, so that the color adjustment range is set. You may control.

  Further, for example, a mode in which the color adjustment range is set according to the color gamut of the print display color and a mode in which the color adjustment range is set regardless of the color gamut of the print display color may be switched. Specifically, for example, a mode in which the color adjustment range is set regardless of the color gamut of the print display color is set as the initial mode, and when a specific operation is performed, the color adjustment range is set according to the color gamut of the print display color. You may employ | adopt GUI which switches to the mode set.

  Further, for example, the print color characteristic may correspond to the print display color of a specific model of the printer, or may correspond to the print display color of a general printer. For example, an ICC profile such as Japan Color 2001 Corted or Japan Color 2001 Uncored may be used as the print color characteristic.

  Further, instead of defining the print color characteristics for all the print display colors, the print color characteristics may be defined for a part of the print display colors. For example, it may be defined only for the print display color with the highest saturation that defines the print color gamut, or the print color characteristics may be defined for discrete print display colors on the premise of interpolation calculation.

  Further, instead of defining the print display color with the PCS gradation value in the print color characteristics, it may be defined with the gradation value of the color space (for example, sRGB or Adobe RGB) in which the color data is to be interpreted. Even if the print color characteristics are defined by the gradation value of the color space in which the color data is to be interpreted, the print display color is defined via a device-independent color space such as CIE L * a * b * or CIE XYZ. There is no substitute for being done. The color space for defining the print display color is not limited to these color spaces, and any color space may be used as long as the definition can be shared between the display and the printer.

  The present invention is not limited to color adjustment processing in a PC, but may be applied to color adjustment processing in a digital camera or a photo viewer.

1: Image processing device, 3: Printer, 11: Display control unit, 12: Hard disk device, 13: Interface, 20: Edit window, 21, 22, 23: Slider, 21a, 22a, 23a: Status bar, 24: Sub window , 31: display, 32: keyboard, 33: mouse, D1: print color characteristics, D2: image data, P1: image processing program, P11: GUI module, P12: adjustment range setting module, P13: color adjustment module

Claims (4)

Print color characteristic acquisition means for acquiring print color characteristics including the color gamut of the print display color;
Means for obtaining image data;
Operation means for accepting an operation for adjusting the color of the image data in an adjustment range;
Adjustment range setting means for setting the adjustment range in which the color of the image data falls within the color gamut of the print display color based on the print color characteristics;
Color adjusting means for adjusting the color of the image data in accordance with the accepted operation;
An image processing apparatus comprising: The adjustment range setting means analyzes the image data, and sets the adjustment range based on an analysis result and the print color characteristics.
The image processing apparatus according to claim 1. Get print color characteristics including color gamut of print display color,
Get image data,
Accepting an operation to adjust the color of the image data in the adjustment range,
Setting the adjustment range in which the color of the image data falls within the color gamut of the print display color based on the print color characteristics;
Adjusting the color of the image data in accordance with the accepted operation;
An image processing method. Print color characteristic acquisition means for acquiring print color characteristics including the color gamut of the print display color;
Means for obtaining image data;
Operation means for accepting an operation for adjusting the color of the image data in an adjustment range;
Adjustment range setting means for setting the adjustment range in which the color of the image data falls within the color gamut of the print display color based on the print color characteristics;
Color adjusting means for adjusting the color of the image data in accordance with the accepted operation;
Image processing program that makes the computer function.

Images