JP4411228B2 - Color processing method and apparatus - Google Patents

Description

  The present invention relates to converting input color data into output data represented by a plurality of color components including a black component.

  FIG. 12 is a conceptual diagram showing color matching between general different devices.

  Input data that is RGB data or CMYK data is converted into XYZ data in a color space that does not depend on a device by an input profile. Since colors outside the color gamut of the output device are not represented by the output device, the color space is converted to input data that has been converted to device-independent color space data so that all of the colors fall within the color gamut of the output device. Compression is applied. After the color space compression, the input data is converted from the device-independent color space to the CMYK data in the color space depending on the output device.

  According to FIG. 12, color matching between different devices can be realized by passing through XYZ values (or Lab values) that do not depend on devices. However, when converting from an XYZ value to a CMYK value, since there are a plurality of combinations of CMY values and K values for one XYZ value, a black plate (K plate) is generated to obtain one solution. It was necessary to fix the characteristics.

  If the characteristics of the black plate generation are fixed, the combination of the CMY value and the K value can be uniquely determined for the XYZ value. However, because the characteristics of black plate generation are determined, in the case of conversion from CMYK values to CMYK values, even if the combination of input CMY values and K values is changed, the change cannot be reflected in the output data. Problems arise. For example, if the CMYK value A1 ′ is output with respect to the input of the CMYK value A1, even if the input CMY value is increased, the K value is decreased, and another CMYK value A2 expressing the same color is input, Since the XYZ values of the expressed colors are the same, it can be seen that the output data becomes the CMYK value A1 ′ according to the characteristics of the black plate generation.

  For the same reason, when gray is output in response to an input of CMYK values, even if the input data is K single color (0, 0, 0, K), the output data is K single color (0, 0, 0, K '). However, in the field of Graphic Arts, characters and the like are often expressed in K single colors in CMYK values, and it has been desired to output K single colors for black K input (black plate compensation).

  Therefore, Patent Document 1 proposes a method for realizing black plate compensation.

  The printer profile defined by the International Color Consortium (ICC) includes an AToBxTag (a tag that describes color conversion from a device-dependent color space to a PCS using an LUT) in order to perform mutual conversion between PCS and device-dependent colors. BToAxTag (a tag in which color conversion from PCS to device-dependent color space is described in LUT or the like) is stored.

  FIG. 14 shows a processing flow, and FIG. 13 shows an initialization process for black plate compensation.

  In FIG. 14, it is first determined whether or not the black plate compensation is ON / OFF (41).

  When the black plate compensation is OFF, conversion from a general CMYK value to a CMYK value is performed using AToBxTag of the source profile 11 and BToAxTag of the destination profile 12. Here, even if K single color is input, the output is a CMYK value (other than K single color) determined by the characteristics of the black plate generation.

  On the other hand, when the black plate compensation is ON, an initialization process 31 for black plate compensation is executed.

  Hereinafter, the flow of the initialization process 31 for black plate compensation will be described (see FIG. 13).

  First, AtoBxTag is read from the CMYK profile 12 on the destination side (32). In AToBxTag, color conversion from the CMYK value of the destination device to the PCS (for example, the CMYK value to the Lab value) is described in an LUT or the like.

  Next, K single color (0, 0, 0, K) is pseudo-input (for example, K = 0 to 255) as an input for color conversion of AToBxTag, so that K single color (K = 0 to 255) is input. Lab values can be obtained. Here, since only the L * value (lightness information) is required, a * and b * are ignored (33). If PCS is an XYZ value, it is converted to a Lab value.

  Thereby, the KL characteristic as shown in the graph 34 is obtained.

  Next, the KL characteristic (graph 34) is inversely converted to obtain the LK characteristic (graph 36) (35). Here, the LK characteristic indicates a K monochrome value corresponding to the lightness L *.

  When the above-described initialization process 31 for black plate compensation is completed, it is determined whether or not there is K single color for each CMYK value input (42).

  The input CMYK value is C! = 0 or M! = 0 or Y! When = 0 (when any of CMY has a value other than 0), the input CMYK value is determined to be other than K single color, and AToBxTag of the source profile 11 and BToAxTag of the destination profile 12 are used. A general conversion from CMYK values to CMYK values is performed.

  On the other hand, when the input CMYK value is C = M = Y = 0, the input CMYK value is determined to be K monochrome.

For the K single color, the AToBxTag of the source profile 11 and the LK characteristic obtained in the initialization process 31 for black plate compensation are applied. That is, the Lab value (or XYZ value) for the source side K monochrome is obtained by AToBxTag, and the destination side K monochrome is obtained by the LK characteristic (when PCS is an XYZ value, it is converted to the Lab value). To do).
JP 2004-120566 A

  In the conventional black plate process, color space compression like BToAxTag of the destination profile 12 is not considered in the LK characteristic obtained by the initialization process 31, and therefore, for the K single color using the LK characteristic. There may be a difference in brightness of the matching result between the processing and the processing for non-K single color using BToAxTag.

  The invention described in claim 1 is a color processing method for converting input color data into output data represented by a plurality of color components including a black component, and is device-independent from device-dependent data according to a destination profile. Whether or not the brightness component-black component conversion data for converting the brightness component value into the black component value is generated from the first conversion data to be converted into the following data, and whether the input color data is color data indicating an achromatic color or not When the input color data is determined to be achromatic color data, brightness component-black component conversion data is used to determine that the input color data has 0 color components other than the black component. A color processing method for converting to output color-data. The conversion is performed according to a source profile when the input color data is determined to be achromatic color data. The input color data is converted into device-independent data using second conversion data for converting device-dependent data into device-independent data, and the device-independent data according to the destination profile is converted into a device. The converted device-independent data is converted into destination device-dependent data using third converted data that is converted into dependent data, and the converted destination data is converted using the first converted data. The brightness of the destination device-independent data converted using the first conversion data using the brightness component-black component conversion data after converting the device-dependent data into device-independent data The value of the black component of the output color data is obtained from the brightness of the component, and the input color data indicates an achromatic color If it is determined that the data is not color data, the input color data is converted into output data represented by a plurality of color components including a black component using the second conversion data and the third conversion data. And

  The invention described in claim 2 is a color processing method for converting input color data into output data represented by a plurality of color components including a black component, from device-dependent data corresponding to a destination profile to device-independent Whether or not the brightness component-black component conversion data for converting the brightness component value into the black component value is generated from the first conversion data to be converted into the following data, and whether the input color data is color data indicating an achromatic color or not When the input color data is determined to be achromatic color data, brightness component-black component conversion data is used to determine that the input color data has 0 color components other than the black component. The output color-data conversion method converts the output color to data. When the input color data is determined to be achromatic color data, the conversion is performed according to a source profile. Input color data is converted to device-independent data using second conversion data that converts device-dependent data into device-independent data, and color space compression processing is performed according to the color reproduction range of the destination device. , Performed on the converted device-independent data, using the brightness component-black component conversion data, to determine the value of the black component of the output color data from the brightness of the color space compressed data, When it is determined that the input color data is not color data indicating an achromatic color, the second conversion data, the color space compression processing, and device-independent data are converted into destination device-dependent data. A color processing method for converting the input color data into output data represented by a plurality of color components including a black component by using conversion data

  According to the present invention, an achromatic input color can be reproduced as a single black color based on the color reproduction range of the output device.

Example 1
Hereinafter, the black plate compensation considering the color space compression processing will be described.

<Black compensation in color conversion from CMYK values to CMYK values considering color space compression processing>
The black plate compensation in color conversion from CMYK values to CMYK values in consideration of color space compression processing will be described with reference to FIG. The initialization process is the same as in FIG. Further, in FIG. 1, the same processing as in FIG. 14 is denoted by the same reference numerals and description thereof is omitted.

  In the process of FIG. 14, since the color space compression like BToAxTag of the destination profile 12 is not considered in the LK characteristic obtained by the initialization process 31, the process for K single color using the LK characteristic And the brightness of the matching result may occur between the non-K single color processing using BToAxTag.

  In order to improve this point, as shown in FIG. 1, when the black plate compensation is ON and the input color data is K single color (that is, the input color is an achromatic color), the source profile 11 The input color data is converted into Lab values using AtoBxTag. Next, processing by the destination profile 12 using BToAxTag and AToBxTag is performed.

  For the L value of the Lab value obtained using AtoBxTag of the destination profile 12, the K value is calculated using the LK characteristic (graph 36) obtained in the initialization 31.

  The BtoAxTag of the destination profile 12 takes into account color space compression processing based on the color reproduction range of the destination device. Therefore, according to the present embodiment, the LK characteristic can be applied to the lightness after color space compression. Therefore, the brightness of the matching result can be matched between the K single color process using the LK characteristic and the non-K single color process using BToAxTag.

  It should be noted that the processing by BmutAxTag and AToBxTag of the destination profile 12 can be prioritized if the destination profile 12 includes gamutTag.

<Black compensation in color conversion from RGB values to CMYK values in consideration of color space compression processing>
When the source profile is a monitor profile, a 3 × 3 matrix and gamma characteristics for conversion from device-dependent colors to PCS are stored.

  FIG. 2 shows a processing flow in black plate compensation in color conversion from RGB values to CMYK values. In addition, about the process similar to FIG. 1, the same code | symbol is attached | subjected and description is omitted.

  The processing contents are almost the same as the color conversion from the CMYK value to the CMYK value, but it is not determined whether or not the color is a single K color (achromatic color), but is determined whether or not R = G = B (52). .

  The source profile 11 stores a 3 × 3 matrix and a gamma characteristic, and the device RGB is converted to linear RGB by the gamma characteristic, and the linear RGB is converted to XYZ value by the 3 × 3 matrix. Conversion from XYZ to Lab is performed based on a known conversion method. Although the conversion data stored in FIG. 1 is different from that in FIG. 1, the processing using the source profile in color matching has the same meaning, and thus the same reference numeral is given.

<Black compensation in color conversion from GRAY value to CMYK value considering color space compression processing>
When the source profile is a GRAY profile, a 1D LUT or the like for converting device-dependent colors to PCS is stored.

  FIG. 3 shows a processing flow in the black plate compensation in the color conversion from the GRAY value to the CMYK value. In addition, about the process similar to FIG. 1, the same code | symbol is attached | subjected and description is omitted.

  The processing contents are almost the same as the color conversion from the CMYK value to the CMYK value. However, it is not determined whether the color is K single color, but is automatically set to K single color output when the black plate compensation is ON.

  A 1D LUT is stored in the source profile 11. The 1D LUT converts the device GRAY to a luminance value, and converts the luminance value into the XYZ value by integrating the XYZ values of the white point.

  As described above, according to the present embodiment, when the black plate compensation is ON and the input color data is a single black color, the black single color is considered in consideration of the color reproduction range of the output device (destination device). Can be converted to output data. Therefore, the brightness of the matching result can be matched between the K single color process using the LK characteristic and the non-K single color process using BToAxTag.

(Example 2)
The color perception model is a human color perception space such as CIE CAM97s, CAM02, for example, for converting XYZ values under the viewing condition VC1 (including W1) into XYZ values under the viewing condition VC2 (including W2). This is a conversion method using QMH (or JCH). Here, Q of QMH represents brightness, M represents colorfullness, H represents huequadture or hueangle, JCH of JCH represents lightness, C represents chroma, and H represents huequature or hueangle. When this conversion method is applied to the Lab uniform color space, the Lab value under W1 and the Lab value under W2 do not match as in the Von Kries conversion. For example, the XYZ value of the sample under W1 (Xw1, Yw1, Zw1) is (X1, Y1, Z1), and the XYZ value of the sample under W2 (Xw2, Yw2, Zw2) is (X2, Y2, Z2). When doing so, according to the color perception model, the following transformations are performed:
(X1, Y1, Z1) → [CIE CAM97s forward conversion] → (Q, M, H) or (J, C, H) → [CIE CAM97s inverse conversion] → (X2, Y2, Z2) color perception model is used FIG. 4 shows an example in which color matching under different observation conditions is realized.

<C Black Compensation in Color Conversion from CMYK Value / RGB Value / GRAY Value to CMYK Value Considering Observation Conditions>
When the observation conditions are considered, the basic processing flow is the same as in FIG. 14, but the observation conditions are considered in the initialization process 31 for black plate compensation and the processing for the source profile 11 and the destination profile 12. There is a need to.

  In the black plate compensation, a reference observation condition (for example, an office observation condition at D50) is set in advance, and the profile is considered in consideration of the observation condition when the KL characteristic derivation 34 of the initialization process 31 is performed. The color perception model is applied so that the L value under the reference observation condition is changed from the observation condition set in the inside.

  When actually processing the input color data of K single color, the L value under the observation condition of the source profile 11 obtained by the AtoBxTag 11 of the source profile 11 is set when the KL characteristic derivation 34 is performed. The color perception model is converted into the L value under the reference observation condition. Then, the K monochrome is obtained by applying the LK characteristic under the reference observation condition derived by the initialization process 31 to the L value under the reference observation condition.

  The observation conditions can be considered by applying the same processing as in FIG. 4 to the case where the black plate compensation is OFF or the input other than the K single color.

  Further, the difference in processing between the case of CMYK values and the case of RGB values / GRAY values is the same as in the first embodiment. Therefore, by applying the processing procedure for the CMYK value to the processing procedure for the RGB value / GRAY value, it is possible to realize black plate compensation in consideration of the observation conditions as in the case of the CMYK value.

(Example 3)
FIG. 5 shows a conceptual diagram of color matching using color space compression on a human color perception space.

  First, the input side device model 1101 and the output side device model 1106 are generated using the colorimetric values 1111 or the colorimetric values 1114. The device model includes forward conversion (corresponding to the processing of ICC profile AToB1Tag) and backward conversion (corresponding to the processing of ICC profile BToA1Tag). Device characterization is based on colorimetric values, conversion data for forward conversion (from device-dependent data to device-independent data) and backward conversion (from device-independent data to device-dependent) Conversion data for performing conversion to data).

  The forward conversion data is generated by reading a colorimetric value file (1111 or 1114) that describes the correspondence between device colors and colorimetric values, and generating a multidimensional LUT or conversion formula that converts device colors to XYZ values. To do. The reverse conversion data is generated by converting the XYZ values into device colors by using the result of the forward conversion and performing reverse conversion of the forward multidimensional LUT or optimizing the polynomial parameters by the regression analysis method. LUT or conversion formula is generated.

  Here, the color space that does not depend on the colorimetric value or the device need not be limited to XYZ, and may be a color space such as Lab or Luv.

  Next, the color reproduction range 1107 (or 1108) of the input side device and the color reproduction range 1109 (or 1110) of the output side device in the human color perception space are obtained. In the case of the relative mode, JCh is selected as the human color perception space, and in the case of the absolute mode, QMh is selected.

  The color gamut 1107 (or 1108) of the input side device is a color perception model for the XYZ values of the entire input side device obtained from the colorimetric values of the colorimetric value file 1111 and the forward conversion result of the device model 1101. It can be obtained by applying forward transformation and creating a three-dimensional convex hull (Convex Hull) of the obtained JCh (or QMh) value. The color reproduction range is a three-dimensional solid including the obtained JCh (or QMh) value.

  The color reproduction range 1109 (or 1110) of the output-side device is also the order of the color perception model with respect to the XYZ values of the entire output-side device obtained from the colorimetric values of the colorimetric value file 1114 and the forward conversion result of the device model 1106 It can be obtained by applying direction transformation and creating a three-dimensional convex hull (Convex Hull) of the obtained JCh (or QMh) value.

  Here, the input side viewing condition 1112 is set for the input side color perception model, and the output side viewing condition 1113 is set for the output side color perception model. The color perception model need not be limited to CIECAM02, CIECAM97s, etc., but any color perception model that can predict human color perception parameters J, C, Q, M, h, H is another color perception model. It doesn't matter.

  Based on the input-side and output-side device models and the color reproduction range thus generated, color matching is performed.

  Color conversion from the input device color to the output device color in consideration of color space compression on the human color perception space JCh can be performed by the following processing.

  First, the XYZ value is obtained by applying the forward conversion of the input device model 1101 to the input color. Next, the forward direction conversion of the color perception model 1102 based on the input side observation condition 1112 is applied to obtain the JCh value. Next, color space compression 1103 is performed based on the color reproduction range 1107 of the input device and the color reproduction range 1109 of the output device. An XYZ value is obtained by applying a reverse transformation of the color perception model 1105 based on the output side observation condition 1113 to the JCh value after color space compression. Then, the output color is obtained by applying the reverse transformation of the output side device model 1106.

  Similarly, the color conversion from the input device color to the output device color in consideration of the color space compression on the human color perception space QMh, similarly, the color reproduction range 1108 of the input device and the color reproduction range 1110 of the output device. , And color space compression 1104 or the like.

  According to the color matching shown in FIG. 4, optimal color space compression can be performed for a combination of color reproduction ranges of an input side device and an output side device to be color matched.

<Black Plate Compensation in Color Conversion from CMYK Value / RGB Value / GRAY Value to CMYK Value Considering Color Space Compression in Human Color Perception Space>
A processing procedure for realizing black plate compensation in color matching using color space compression in the human color perception space shown in FIG. 5 will be described.

  FIG. 6 shows an initialization process for black plate compensation in this embodiment. FIG. 7 shows the processing flow for CMYK input, FIG. 8 for RGB input, and FIG. 9 for GRAY input.

The source profile 1101 in FIGS. 7, 8, and 9 corresponds to the input side device model (input side forward conversion data) 1101 in FIG. The destination profile 1106 corresponds to the output side device model (output side inverse transform data) 1106. 5 and 7, 8, and 9, the same reference numerals indicate the same processing even if the notation method is different.
First, ON / OFF of the black plate compensation is determined (1301).

  When the black plate compensation is OFF, the process shown in the conceptual diagram of FIG. 5 is performed.

  On the other hand, when the black plate compensation is ON, an initialization process 1201 for black plate compensation is executed.

  FIG. 6 shows an initialization process for black plate compensation.

  First, the colorimetric value file 1114 of the destination device is read (1202), the lightness L * (or luminance Y) characteristic for the K single color is calculated by applying linear interpolation or the like to the colorimetric value, and the KL characteristic ( A graph 1204) is derived (1203). Next, an LK characteristic (graph 1206) that is an inverse transformation of the KL characteristic is derived (1205).

  When the initialization process 1201 for black plate compensation is completed, it is determined whether or not the input color is K single color (when CMYK is input) and R = G = B (when RGB is input) (1302).

  When the input color is other than K single color and other than R = G = B, the same processing as the black plate compensation OFF is performed, and the color reproduction of the destination device is performed from the color reproduction range 1107 (or 1108) of the source device. Color space compression to the range 1109 (or 1110) is performed. FIG. 10A shows a color reproduction range 1601 of the source device and a color reproduction range 1602 of the destination device.

  On the other hand, when the input color is K single color (when CMYK is input), R = G = B (when RGB is input), and gray (when GRAY is input), processing for compensating the black plate is performed.

  As the color reproduction range 1107 (or 1108) of the source side device, the entire input colors of K, R = G = B, and gray (for example, K = 0 to 255 for 8-bit input, R = G = B = 0 to 255, GRAY = 0 to 255) color reproduction range (hereinafter referred to as achromatic color reproduction range) 1603, destination side device color reproduction range 1109 (or 1110), K single color output color whole area (in case of 8-bit output) For K = 0 to 255), a color reproduction range (hereinafter referred to as K single color reproduction range) 1604 is obtained (see FIG. 16A).

  In the color space compression 1103 (or 1104) on the human color perception space, the achromatic color reproduction range 1603 is included in the K single color reproduction range 1604 in consideration of the lightness (or luminance) of the input / output color reproduction range. Mapping (color space compression 1103 or 1104) is performed.

  In this case, color space compression when the input color is other than K single color and R = G = B (hereinafter referred to as chromatic color space compression) and color space compression when K is single color and R = G = B (hereinafter referred to as achromatic color). Spatial compression) not only has different brightness (or luminance) ranges, but also different compression methods. Therefore, there may be a deviation in brightness (or luminance) in the output results of chromatic color space compression and achromatic color space compression. For example, when the color space compression of the chromatic color space compression is Perceptual, there is a possibility that non-linear lightness compression is performed. Therefore, when the achromatic color space compression is linear lightness compression, the input color As a result, even if the colors have the same brightness, the output colors have different brightness. Therefore, in achromatic color space compression, in order to realize color space compression with little difference in brightness (or luminance) from chromatic color space compression and maintaining a certain degree of gradation, for example, lightness (or luminance) of an input color. Is equivalent to within (α + β)% of the K single color reproduction range 1603, the lightness (or luminance) obtained by the chromatic color space compression is output by the LK (or YK) characteristic, and (α + β ) If it corresponds to other than%, the lightness (or luminance) obtained by mapping such that the input color in the achromatic color reproduction range is within the K single color reproduction range is output by the LK (or YK) characteristic. That's fine. Here, α% and β% indicate a ratio from the point of 50% with respect to the entire K single color reproduction range 1603, and the maximum lightness of the achromatic color reproduction range is Jmax1, the minimum lightness is Jmin1, and the K single color reproduction range. If the maximum brightness is Jmax2 and the minimum brightness is Jmin2, α% and β% are determined as follows, for example:

  FIG. 16B shows an example in which the chromatic color space compression is Colorimetric and the input color of the achromatic color reproduction range 1603 corresponding to a portion other than α% of the K single color reproduction range 1604 is linearly color space compressed. It is a thing. Here, the color space compression corresponding to a portion other than α% of the K single color reproduction range 1604 does not need to be linear, and is a nonlinear connection in which the chromatic color space compression (portion within α%) and the gradient are continuously connected. It may be a characteristic.

The L value obtained by performing such color space compression (1103) and CAM- ¹ (1105) is converted using the LK characteristic 1206 to obtain the K value.

  According to the processing of this embodiment, color space compression is performed in consideration of the color reproduction range for the input side K single color, R = G = B, GRAY and the color reproduction range for the output side K single color, R = G = B, GRAY. Do. Therefore, highly accurate black plate processing can be realized.

(Modification)
Whether to apply the black plate compensation can be set independently in the color matching function (MatchColors) for the color list and the color matching function (MatchPixmap) for the raster image.

  As shown in FIG. 11, when color matching is performed, whether to apply black plate compensation may be selected for each object type via the user interface (FIG. 7). For each correction, the black plate compensation is turned on by turning on the check box. In the case of GRAY input, color matching from GRAY value to CMYK, in the case of RGB input, color matching from RGB value to CMYK value, CMYK input The case is effective only in color matching from CMYK values to CMYK values.

  A program code of software for realizing the functions of the above-described embodiment is applied to an apparatus or a computer in the system connected to the various devices so as to operate the various devices so as to realize the functions of the above-described embodiments. What is implemented by operating the various devices in accordance with a program stored in a computer (CPU or MPU) of the system or apparatus supplied is also included in the scope of the present invention.

  In this case, the program code of the software itself realizes the functions of the above-described embodiments, and the program code itself and means for supplying the program code to the computer, for example, a memory storing the program code The medium constitutes the present invention.

  As a storage medium for storing the program code, for example, a floppy (registered trademark) disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

  Further, by executing the program code supplied by the computer, not only the functions of the above-described embodiments are realized, but also the OS (operating system) in which the program code is running on the computer, or other application software Needless to say, the program code is also included in the embodiment of the present invention even when the functions of the above-described embodiments are realized in cooperation with the embodiment.

  Further, the supplied program code is stored in the memory provided in the function expansion board of the computer or the function expansion unit connected to the computer, and then the CPU provided in the function expansion board or function storage unit based on the instruction of the program code However, it is needless to say that the present invention also includes a case where the function of the above-described embodiment is realized by performing part or all of the actual processing.

Black plate compensation in color conversion from CMYK values to CMYK values considering color space compression Black plate compensation in color conversion from RGB values to CMYK values considering color space compression Black compensation in color conversion from GRAY value to CMYK value considering color space compression Conceptual diagram of color matching under different viewing conditions Conceptual diagram of color matching using color space compression on color perception space Initialization processing for black plate compensation according to the third embodiment Ink compensation in color conversion from CMYK values to CMYK values in consideration of color space compression according to the third embodiment Black plate compensation in color conversion from RGB values to CMYK values in consideration of color space compression according to the third embodiment Black compensation in color conversion from GRAY values to CMYK values in consideration of color space compression according to the third embodiment Color reproduction range 1601 of the source side device, color reproduction range of the destination side device User interface for black compensation Conceptual diagram showing color matching between different devices in the past Initialization processing for conventional black plate compensation Conventional black plate compensation

Claims (7)

A color processing method for converting input color data into output data represented by a plurality of color components including a black component,
Generating brightness component-black component conversion data for converting the brightness component value into the black component value from the first conversion data for converting the device-dependent data according to the destination profile to the device-independent data;
Determine whether the input color data is color data indicating an achromatic color,
When it is determined that the input color data is a color data indicating an achromatic color, the input color data is output color having a color component other than the black component is 0 using brightness component-black component conversion data. -Color processing method to convert to data,
The transformation is
When it is determined that the input color data is color data indicating an achromatic color,
Converting the input color data into device-independent data using second conversion data for converting device-dependent data according to a source profile into device-independent data;
Using the third conversion data for converting the device-independent data corresponding to the destination profile into the device-dependent data, and converting the converted device-independent data into the destination device-dependent data;
Using the first converted data, the converted destination device dependent data is converted into device independent data,
Using the brightness component-black component conversion data, the value of the black component of the output color data is obtained from the brightness of the brightness component of the destination device-independent data converted using the first conversion data. ,
When it is determined that the input color data is not color data indicating an achromatic color,
A color processing method comprising: converting input color data into output data represented by a plurality of color components including a black component using the second conversion data and the third conversion data. A color processing method for converting input color data into output data represented by a plurality of color components including a black component,
Generating brightness component-black component conversion data for converting the brightness component value into the black component value from the first conversion data for converting the device-dependent data according to the destination profile to the device-independent data;
Determine whether the input color data is color data indicating an achromatic color,
When it is determined that the input color data is a color data indicating an achromatic color, the input color data is output color having a color component other than the black component is 0 using brightness component-black component conversion data. -Color processing method to convert to data,
The transformation is
When it is determined that the input color data is color data indicating an achromatic color,
Using the second conversion data that converts device-dependent data according to the source profile to device-independent data, the input color data is converted to device-independent data,
A color space compression process corresponding to the color reproduction range of the destination device is performed on the converted device-independent data,
Using the brightness component-black component conversion data , obtain the value of the black component of the output color data from the brightness of the color space compressed data,
When it is determined that the input color data is not color data indicating an achromatic color,
A plurality of color components including a black component using the second conversion data, the color space compression processing, and third conversion data for converting device-independent data into destination device-dependent data. A color processing method characterized by converting to output data indicated by The input color data is represented by a plurality of color components including a black component,
The color processing method according to claim 1, wherein the determination includes determining whether a color component value other than a black component of the input color data is zero . The input color data is indicated by red, blue and green components,
It said determining, a red component value, a blue component value, a color processing method according to claim 1, wherein the green component value is determined equal poetry not.   The program for implement | achieving the color processing method in any one of Claims 1 thru | or 4 using a computer. A color processing device that converts input color data into output data represented by a plurality of color components including a black component,
Generation means for generating brightness component-black component conversion data for converting a brightness component value into a black component value from first conversion data that converts device-dependent data according to the destination profile into device-independent data When,
Determining means for determining whether or not the input color data is color data indicating an achromatic color;
When it is determined that the input color data is a color data indicating an achromatic color, the input color data is output color having a color component other than the black component is 0 using brightness component-black component conversion data. -Conversion means for converting to data,
The converting means includes
When it is determined that the input color data is color data indicating an achromatic color,
Converting the input color data into device-independent data using second conversion data for converting device-dependent data according to a source profile into device-independent data;
Using the third conversion data for converting the device-independent data corresponding to the destination profile into the device-dependent data, and converting the converted device-independent data into the destination device-dependent data;
Using the first converted data, the converted destination device dependent data is converted to device independent data,
Using the brightness component-black component conversion data , obtain the value of the black component of the output color data from the brightness component of the destination device independent data converted using the first conversion data ,
When it is determined that the input color data is not color data indicating an achromatic color,
A color processing apparatus that converts input color data into output data represented by a plurality of color components including a black component, using the second conversion data and the third conversion data. A color processing device that converts input color data into output data represented by a plurality of color components including a black component,
Generation means for generating brightness component-black component conversion data for converting a brightness component value into a black component value from first conversion data that converts device-dependent data according to the destination profile into device-independent data When,
Determining means for determining whether or not the input color data is color data indicating an achromatic color;
When it is determined that the input color data is a color data indicating an achromatic color, the input color data is output color having a color component other than the black component is 0 using brightness component-black component conversion data. -Conversion means for converting to data,
The converting means includes
When it is determined that the input color data is color data indicating an achromatic color,
Using the second conversion data that converts device-dependent data according to the source profile to device-independent data, the input color data is converted to device-independent data,
A color space compression process corresponding to the color reproduction range of the destination device is performed on the converted device-independent data,
Using the brightness component-black component conversion data , obtain the value of the black component of the output color data from the brightness of the color space compressed data,
When it is determined that the input color data is not color data indicating an achromatic color,
A plurality of color components including a black component using the second conversion data, the color space compression processing, and third conversion data for converting device-independent data into destination device-dependent data. A color processing apparatus characterized by converting into output data indicated by

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