JP4592089B2 - Image processing method, profile creation method, and image processing apparatus - Google Patents

Description

  The present invention relates to an image processing method, a profile creation method, and an image processing apparatus, and more particularly to a color gamut mapping (gamut mapping) used in a color conversion profile.

  In recent years, digital devices such as digital cameras and image scanners have become widespread, and digital images can be easily obtained. Also, full-color hard copy technology is rapidly developing. In particular, inkjet printing is becoming more widely used because its image quality is comparable to silver salt photography. On the other hand, networks such as the Internet are widely spread, and many users can connect various devices. In an environment where such input / output devices are diverse, the color reproduction range, for example, when a color image signal of a monitor having a certain color reproduction range is hard-copied by a printer with a narrower color reproduction range. Input / output of color image data is performed between devices having different.

  On the other hand, “color management system (hereinafter also simply referred to as“ CMS ”)” is known as a technique for reproducing the same color between different devices.

FIG. 1 is a diagram showing an outline of one configuration of this CMS, and shows a CMS using a device-independent color space. For example, when an image input device such as a camera or a scanner is connected to an image output device such as a printer or monitor, in the configuration shown in FIG. 1, conversion from a color signal of a certain device to a color signal of an output device Device-independent color space (for example, CIE-XYZ, CIE) based on a profile (conversion formula linking each device color to a device-independent color space, or a conversion table in which the above conversion is created in advance as a lookup table: LUT) -L ^* a ^* b ^* ). Such a system has an advantage that a system having different input and output devices to be connected can be easily exchanged.

  By the way, when performing color reproduction with each device in CMS, in order to be able to reproduce colors that can be reproduced with a certain device with an output device, the difference in the color reproduction range between those input and output devices is absorbed. A gamut mapping technique is used.

  In general, the color gamut of a device varies from device to device. For example, the monitor performs color reproduction by additive color mixing by the development of phosphors of three primary colors of red (R), green (G), and blue (B). For this reason, the color gamut of the monitor depends on the type of phosphor used. On the other hand, the color gamut of the printer differs depending not only on the ink used but also on the type of paper.

  FIG. 2 is a diagram showing the relationship between the color gamut of the sRGB color space of the monitor and the color gamut of the inkjet printer, and shows the relationship between brightness and saturation in a certain hue. As shown in the example, when there is an area where the printer color gamut 202 is smaller than the monitor color gamut 201, the color of the monitor color gamut in that area cannot be reproduced as it is by the printer. Therefore, in such a case, it is necessary to perform processing for mapping a color outside the color gamut into the color gamut while keeping the original image information as much as possible. In this way, pushing a color that cannot be physically reproduced into the color gamut by some processing is generally called “color gamut compression”.

  In such color gamut compression, generally, the maximum brightness value and the minimum brightness value in the monitor color gamut that is the mapping source are different from the maximum brightness value and the minimum brightness value in the printer color gamut that is the mapping destination. In this case, although depending on the mapping method, in general, natural color reproduction can be performed in the high saturation portion. However, in the low saturation portion, a difference in the maximum brightness value and the minimum brightness value may cause a decrease in gradation in the low saturation portion of the image output from the printer.

On the other hand, conventionally, the brightness value L ^* in of the printer color gamut that is the mapping destination is normalized to the brightness value L ^* ori of the monitor color gamut of the mapping source (hereinafter referred to as “relative brightness”). ) A method of performing color gamut compression after L ^* std is known. The relative lightness L ^* std is a lightness value obtained by normalizing the paper whiteness L ^* w of the printer to 100 and the black lightness L ^* bk to 0, and the relative lightness L ^* std uses the following formula (1). Can be defined.
L ^* std = (L ^* in−L ^* bk) / (L ^* w−L ^* bk) × 100 (1)

Here, the paper brightness L ^* w of the printer is a brightness value of white (hereinafter, also referred to as “media white”) of the medium of the print medium such as paper used when output using the printer. Specifically, it is a value obtained by measuring the brightness value of the media using a colorimeter. The blackness L ^* bk of the printer is a patch of black (hereinafter also referred to as “process black”) in which the signal value of the image input to the printer is (R, G, B) = (0, 0, 0). It is a lightness value in the L ^* a ^* b ^* space, which is the result of output by a printer and colorimetric using a colorimeter.

  By the way, media white and process black of a printer are not neutral gray but have a saturation component. In general, the saturation component does not disappear even by the above normalization. However, due to the characteristics of human chromatic adaptation, it is desirable that the white and black of the monitor to be compressed, for example, be mapped to media white and process black, respectively, having a saturation component. In addition, in this way, white and black, which are specific points (colors) in one color gamut, are mapped to media white and process black, which are specific points (colors) in the same manner as the other color gamut, respectively. Is preferable in that it is easy to set or map points that determine the direction of compression in gamut mapping.

Here, in the relative conversion of the ICC profile, the CIEXYZ value of the printer color gamut can be converted according to the following equation (2).
Xdst = 96.42 × Xsrc / Xn
Ydst = 100.00 × Ysrc / Yn (2)
Zdst = 82.49 × Zsrc / Zn
In this equation, (Xsrc, Ysrc, Zsrc) represents an XYZ value before conversion, (Xdst, Ydst, Zdst) represents an XYZ value after conversion, and (Xn, Yn, Zn) represents an XYZ value of media white. Yes.

  With this conversion, the media white of the printer gamut can be matched to the white of the monitor being compressed. However, process black cannot be matched with monitor black even by the above conversion.

  On the other hand, in Patent Document 1, a color gamut that matches the gray axis of the monitor with the gray axis of the printer is transformed by translation and rotation of the gray axis of the monitor. Gamut mapping to a region is described. According to this, it is possible to perform mapping in which white and black in the monitor color gamut are matched with media white and process black of the printer, respectively.

Japanese Patent No. 2560972

  However, as described in Patent Document 1, if only one of the color gamuts is deformed, there arises a problem caused by the mutual positional relationship being shifted. For example, in gamut mapping, the color in the monitor color gamut that overlaps the printer color gamut is often mapped to the same color in the printer color gamut as it is. In this case, when only one of the color gamuts is deformed as described above, even if the subsequent mapping is performed with the relationship of mapping as the same color, it is not mapped to the same color of the other color gamut. As a result, there arises a problem that, for example, a color correspondence relationship is impaired such that gamut mapping that is colorimetrically consistent cannot be realized.

  The present invention has been made to solve such a problem. The object of the present invention is to apply a specific color such as white or black in one gamut to the other gamut. It is an object of the present invention to provide an image processing method, a profile creation method, and an image processing apparatus that can be mapped to the same specific color and that do not impair the color correspondence.

To this end, the present invention provides an image processing method for performing a conversion based on a mapping relationship including a compressed mapping from a first color gamut to a second color gamut, wherein at least white and black of the second color gamut rotated to point moves to a point on the achromatic axis, said a step of deforming the second gamut by parallel movement, a region overlapping with the second color gamut of the first color gamut rotation, And a step of deforming the first color gamut by moving in parallel and a step of forming a mapping relationship from the deformed first color gamut to the deformed second color gamut.

A profile creation method for a profile used for conversion based on a mapping relationship including a compressed mapping from a first color gamut to a second color gamut, wherein at least white and black points of the second color gamut are achromatic colors. It rotated to move to a point on the axis, a step of deforming the second gamut by translational movement, the region overlapping the second color gamut of the first color gamut rotation, to translational movement Yes a step of deforming the first gamut, and forming a mapping relation from the first color gamut and the deformed second color gamut which is the deformation, a step of creating a table of the mapping relation, the by It is characterized by that.

Further, the image processing apparatus performs conversion based on a mapping relationship including a compressed mapping from the first color gamut to the second color gamut, wherein at least white and black points of the second color gamut are on the achromatic color axis. rotated to move to a point, and means for deforming the second gamut by parallel movement, the rotation of the region overlapping with the second color gamut of the first color gamut, the by parallel movement And means for deforming the first color gamut and means for forming a mapping relationship from the deformed first color gamut to the deformed second color gamut.

According to the above configuration, the second color gamut is deformed so that at least white and black points of the second color gamut of the printer or the like move to points on the achromatic color axis. Such a conversion relationship is applied to a region that overlaps the second color gamut after the deformation in the first color gamut such as a monitor, and the first color gamut is deformed. It can be mapped to white and black in the second color gamut, for example, white and black in the first color gamut are respectively associated with specific colors in the second color gamut, for example media white and process black Can do. This mapping can make white and black in the first color gamut coincide with white and black in the second color gamut, respectively, so that the compression direction in gamut mapping can be easily set.

  As a result, a specific color such as white or black in one color gamut is mapped to a similar specific color in the other color gamut, and gamut mapping without impairing the color correspondence is possible. .

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 3 is a block diagram showing an image processing apparatus according to an embodiment of the present invention.

  The configuration shown in FIG. 3 shows an example of the configuration of the CMS. Specifically, the image processing apparatus 201 performs color conversion between the image input apparatus 202, the image display apparatus 203, and the image output apparatus 204 in respective profiles. It is a system that executes using The image input device 202 inputs an image in the form of a camera or a scanner. The image display device 203 is in the form of a monitor or the like and displays an image. The image output device 204 is in the form of a printer or the like, and prints out an image. As the printer, for example, an ink jet printer or an electrophotographic printer can be used.

  The image processing apparatus 201 is in the form of a personal computer, and has the following elements to perform processing such as color conversion and profile creation according to the embodiment of the present invention. The image input unit 205 captures an image signal input by the image input device 202. The image display unit 206 generates a display image signal and controls display of the image display device 203 based on the generated image signal.

  The color matching processing unit 207 uses the respective profiles 210, 211, and 212, inputs the image with the image input device 202, displays the image with the image display device 203, and outputs the color with respect to each image signal output with the image output device 204. Perform matching. For example, when an image displayed by the image display device 203 is printed out by the image output device 204, the image output device 204 converts the color of the image signal displayed by the image display device 203 using the monitor profile 211 and the printer profile 212. The image signal of the color gamut is generated. The profile used here uses a lookup table (LUT) created in each embodiment of the present invention, which will be described later with reference to FIG.

  The image processing unit 208 generates color material signals such as ink used in the image output device 204 from the image signal in the color gamut of the image output device 204 obtained by the color matching processing unit 207 as described above. Processing and γ correction processing. The image output unit 209 outputs a print signal to the image output device 204 based on the image signal obtained by the image processing unit 208.

  The image processing apparatus 201 also performs processing for creating a camera profile 210, a monitor profile 211, and a printer profile 212, which will be described later with reference to FIG.

In the following, several embodiments of profile creation based on the configuration shown in FIG. 3 will be described.
(Embodiment 1)
In the first embodiment of the present invention, “colorimetric” color gamut compression is performed. That is, when mapping from the monitor color gamut to the printer color gamut, the colors included in the printer color gamut are faithfully mapped to the colors as they are in the monitor color gamut. On the other hand, compression mapping is performed for colors outside the printer gamut, and the mapping destination is set as an outer portion of the printer gamut (a boundary portion of the printer gamut).

  As described above with reference to FIG. 2, the white Wm of the monitor gamut 201 is mapped to the media white Wp of the printer gamut 202, and the black Km of the monitor gamut 201 is mapped to the process black Kp of the printer gamut 202. It is desirable. This is because the white and black of the monitor to be mapped are preferably mapped to the media white and process black, respectively, which have a saturation component, due to the characteristics of human chromatic adaptation. When color gamut compression is executed, the compression direction must be adaptively changed, and the color gamut compression processing becomes complicated accordingly.

  Therefore, in the present embodiment, as shown in FIG. 4, the printer color gamut 202 (broken line) is rotated and translated based on the white point Wp and the black point Kp, and converted to the color gamut 402 (solid line). The white Wp and black Kp of the printer color gamut 202 are placed on the lightness axis (achromatic color axis). That is, the white Wp ′ and the black Kp ′ in the printer color gamut 402 after the conversion are on the lightness axis. Thus, in the mapping of the color gamut thus transformed, the white Wm and black Km of the monitor are mapped to the white Wp ′ and black Kp ′ of the printer, respectively, so that the media white Wp and the process black Wk are mapped. Can be associated. In this mapping, the white Wm and black Km of the monitor can be matched with the white Wp ′ and black Kp ′ of the printer, respectively, so that the compression direction can be easily set. The above conversion can be easily performed by, for example, determining a matrix of parallel movement from the black point to the coordinate system and a rotation matrix that matches the vector KpWp from the black point to the white point with the lightness axis in the coordinate system. Can be realized.

  With the above modification, the white Wm and black Km of the monitor color gamut 201 are transferred to the media white Wp of the printer color gamut 202 having a saturation component through mapping to the white Wp ′ and black Kp ′ of the printer color gamut. In addition, it is possible to map to the process black Wk, and it becomes easy to set the compression direction when realizing this mapping.

  In the present embodiment, the above modification is also applied to the monitor color gamut 201.

  That is, the area that overlaps the printer color gamut 402 in the monitor color gamut 201 is an area that does not need to be compressed. If the deformation due to the above rotation is applied to this region, the relative positional relationship of the same color is lost. Therefore, for the monitor color gamut 201, the above-described modification is applied to an area overlapping with the printer color gamut. When this deformation is performed, for example, in a region where the printer color gamut is larger than the monitor color gamut as in region A shown in FIG. 4, the shape of the color gamut curves in the deformed monitor color gamut 401 (solid line). Also occurs. However, this color gamut is a color gamut that can be reproduced by a printer, and is not particularly problematic because it maintains a relative relationship due to deformation.

  Specifically, the deformation of the monitor color gamut is applied to the area of the monitor color gamut that overlaps the printer color gamut. In addition, as in the area B shown in FIG. 4, the above-described deformation is weighted and applied to an area close to the boundary of the printer color gamut outside the printer color gamut. Thereby, the continuity of deformation of the monitor color gamut can be maintained. For example, a weighting coefficient corresponding to the distance from the boundary of the printer color gamut 402 in the monitor color gamut can be used so that the deformation is zero in the outline (boundary) of the monitor color gamut 401. In the actual lookup table creation, the monitor color gamut is divided into predetermined grid points and gamut mapping is performed, so that the continuity of deformation can be easily maintained.

  In the gamut mapping of the monitor color gamut whose color gamut has been deformed as described above to the printer color gamut, first, the point of the monitor color gamut 401 after the modification is determined inside / outside with respect to the printer color gamut 402 after the modification, When it is determined, the color (point) itself is associated as a mapping destination. On the other hand, if it is determined to be outside, for example, compression is performed toward a predetermined point on the lightness axis (for example, lightness 50), and a point on the printer color gamut boundary is associated as a mapping destination. By executing this for all the color gamuts, “colorimetric” gamut mapping can be realized.

  In this way, deforming only one of the two color gamuts means that the relative positional relationship with each other changes. This is a fatal problem for “colorimetric coincidence” color gamut mapping. Therefore, in this embodiment, by applying the “deformation” of the printer color gamut to the monitor color gamut, the relative positional relationship is preserved particularly in an area where the color gamut need not be compressed. As a result, it is possible to improve the accuracy of mapping in an area where color gamut compression is not required. Further, by placing white and black of the printer color gamut on the brightness axis, the convergence point at the time of color gamut compression can be fixed, so that the compression process can be facilitated.

  In the above-described embodiment, the rotation conversion is shown as an example of the conversion for placing the media white and the process black on the lightness axis. However, it goes without saying that the application of the present invention is not limited to this.

For example, the saturation component (a ^* , b ^* ) of the media white is subtracted for the brightness of the media white, the saturation component is subtracted for the brightness of the process black, and the brightness of the other colors is shown in FIGS. As shown in b), a conversion may be performed in which a saturation component that is linearly continuous with respect to lightness is calculated from the two saturations and is subtracted. FIG. 5A shows Δa ^* related to brightness, and similarly, FIG. 5B shows Δb ^* related to brightness. Further, as shown in FIGS. 6A and 6B, the saturation component to be subtracted may be configured non-linearly with respect to lightness. In this way, by performing conversion for subtracting the saturation of at least the media white Wp and the process black Kp, these colors are converted into white Wp ′, which is a color on the lightness axis, in the same manner as in the embodiment described in FIG. And black Kp ′. In either case, white and black in the monitor color gamut are not deformed by setting the saturation value to be subtracted at lightness 0 and 100 to 0.

In addition, in the rotation conversion described above, the deformation with respect to only the saturation direction can be realized by excluding the deformation with respect to the brightness. Further, the above-described modification may be applied only to the area near the media white and the process black. For example, a weight related to lightness is set as in FIG. That is, the lightness value of media white and process black is 1, and the weight is 0 when L ^* = 0 and L ^* = 100 (the weight may be set between media white and process black as necessary). The weights are continuously defined so that the amount of movement in the saturation direction of the rotation conversion is multiplied by the weight according to the lightness value before conversion, and the deformation is applied.

  The above-described conversion of the color gamut mapping is performed using a look-up table that realizes the conversion. That is, it is possible to create a conversion table by performing color gamut compression on the above-described conversion on the representative grid data of the monitor color gamut and associating it with the device color of the printer. More specifically, each color gamut is discretely represented by 729 grids, and colors other than these grids are obtained by linear interpolation using grid data, thereby obtaining the color space shown in FIG. Can do.

  In this embodiment, the monitor color gamut has been described as an example of the first color gamut. However, the present invention is not limited to this, and is not limited to the monitor color gamut, and any other color gamut is possible. Of course, this is applicable.

(Embodiment 2)
In the first embodiment described above, so-called “colorimetric coincidence” gamut mapping has been described. However, in this method, the highlight and shadow portions of the monitor may be collapsed and mapped. Therefore, in this embodiment, gamut mapping that reproduces a certain level of gradation in lightness compression is performed.

  FIG. 7 shows a printer color gamut 402 (thin solid line) after modification, similar to the monitor color gamut 401 (dashed line) after modification according to the first embodiment. On the other hand, the highlight portion and the shadow portion of the monitor color gamut 401 are compressed using preset brightness P and Q. That is, mapping is performed in which colors from the lightness P of the monitor color gamut 401 to 100 (maximum lightness point) are compressed into lightness colors from the lightness P of the printer color gamut 402 to the media white Wp. Similarly, colors from the lightness Q of the monitor color gamut 402 to 0 (minimum lightness point) are compressed from the lightness Q of the printer color gamut 402 to the lightness of the process black Kp. Specifically, the lightness compression process described above may be applied to the corresponding grid points. By executing the color gamut compression of the monitor color gamut grid points subjected to lightness compression on the printer color gamut in this way, it is possible to realize color gamut compression that maintains a constant gradation with respect to lightness. .

  Here, since only the monitor color gamut is deformed, the relative positional relationship is impaired. However, most of the lightness compression areas in this embodiment are areas that cannot be reproduced in the printer color gamut. Yes, it is an area that needs some kind of color gamut compression. That is, the gradation collapse and the color shift relating to the brightness are in a trade-off relationship with each other. In addition, since the highlight portion and the shadow portion are generally low in saturation, a color shift caused by lightness compression can be tolerated as compared with gradation collapse relating to lightness, and thus more suitable color gamut compression can be realized.

(Embodiment 3)
The present embodiment relates to “tone-oriented (Perceptual)” gamut mapping, which is one of the main methods of gamut mapping.

  In general, even in “gamut-oriented” color gamut compression, it is not preferable that the correspondence of colors be impaired. Therefore, the monitor and printer color gamut conversion processing is exactly the same as the method described in the first embodiment. The difference is that the color gamut of “colorimetric coincidence” is not the entire printer gamut, but compression is performed so that a certain high saturation area is pushed into the high saturation area of the monitor gamut.

  Specifically, for the converted printer color gamut, for example, as shown by the broken line in FIG. 8A, 80% of the printer color gamut 402 is set as the “colorimetric match” area. The monitor color gamut within this color gamut is mapped faithfully. Further, the remaining monitor color gamut is compressed with respect to the remaining color gamut exceeding the “colorimetric match” area set in this way. For the “colorimetric match” color gamut, for example, a ratio may be set uniformly with respect to the printer color gamut, or the ratio may be partially changed. For example, it is possible to set to 70% for a hue for which gradation is to be partially retained. On the contrary, the gradation is reduced, but it may be set to 95% or the like if it is to be reproduced as faithfully as possible. If a “colorimetric match” region 901 is set as indicated by the broken line in FIG. 8B, the other color gamuts are reproduced as faithfully as possible while maintaining the gradation of the highlight portion and the shadow portion. Will be. That is, color gamut compression equivalent to that of the second embodiment can be realized.

(Other embodiments)
The present invention provides a software program for realizing the functions of the above-described embodiment in 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. The present invention includes those implemented by supplying a code and operating the various devices in accordance with a program stored in a computer (CPU or MPU) of the system or apparatus.

  In this case, the software program code 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, the program code are stored. The storage 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) or other application software in which the program code is running on the computer. It goes without saying that the program code is also included in the embodiment of the present invention even when the functions of the above-described embodiment are realized in cooperation with the above.
Further, after the supplied program code is stored in the memory of the function expansion board of the computer or the function expansion unit connected to the computer, the CPU of 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.

It is a figure which shows the outline | summary of one structure of a color management system. It is a figure which shows the relationship between the color gamut of the color space which a monitor has, and the color gamut of an inkjet printer. 1 is a block diagram illustrating an image processing apparatus according to an embodiment of the present invention. It is a figure explaining the color gamut deformation | transformation which concerns on one Embodiment of this invention. It is a figure explaining the brightness compression of the monitor color gamut based on the modification of the said color gamut modification. It is a figure explaining the brightness compression of the monitor color gamut based on the further modification of the said color gamut modification. It is a figure explaining the color gamut deformation | transformation which concerns on other embodiment of this invention. It is a figure explaining the color gamut deformation | transformation which concerns on other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 201 Image processing apparatus 202 Image input apparatus 203 Image display apparatus 204 Image output apparatus 205 Image input part 206 Image display part 207 Color matching process part 208 Image processing part 209 Image output part 210 Camera profile 211 Monitor profile 212 Printer profile

Claims (16)

An image processing method for performing conversion based on a mapping relationship including a compressed mapping from a first color gamut to a second color gamut,
Transforming the second color gamut by rotating and moving in parallel so that at least white and black points of the second color gamut move to points on the achromatic color axis;
A step of deforming the first color gamut by said rotating a region overlapping with the second color gamut of the first color gamut, parallel movement,
Forming a mapping relationship from the deformed first color gamut to the deformed second color gamut;
An image processing method characterized by comprising: The step of deforming said first gamut is a further, relative to the previous SL region outside the region overlapping with the second color gamut of the first color gamut, the said rotation, the deformation due to parallel movement the 2. The image processing method according to claim 1, wherein the first color gamut is deformed by applying the weight according to the distance from the boundary between the two color gamuts. The rotation, the said deformation by parallel movement, Mu said a translational movement to move the point of the white or black on the achromatic axis, the vector connecting the one and the other of said moving is white or black point The image processing method according to claim 1, wherein the rotation is made to coincide with a chromatic axis. The step of deforming the second color gamut is applied in the vicinity of white and black of the second color gamut and continuously suppresses deformation toward the white and black of the first color gamut. the image processing method according to any one of claims 1 to 3,. After the step of deforming the first color gamut, lightness compression is performed from the maximum brightness of the first color gamut and its predetermined vicinity to white of the second color gamut and its predetermined vicinity, and the first color lightness compression and its vicinity predetermined black from the lowest lightness and near the predetermined range, the according to any of claims 1 to 4, characterized in that the first gamut having further a step of deforming Image processing method. A profile creation method for a profile used for conversion based on a mapping relationship including a compressed mapping from a first color gamut to a second color gamut,
Transforming the second color gamut by rotating and moving in parallel so that at least white and black points of the second color gamut move to points on the achromatic color axis;
A step of deforming the first color gamut by said rotating a region overlapping with the second color gamut of the first color gamut, parallel movement,
Forming a mapping relationship from the deformed first color gamut to the deformed second color gamut;
Creating a mapping table;
A profile creation method characterized by comprising: The step of deforming said first gamut is a further, relative to the previous SL region outside the region overlapping with the second color gamut of the first color gamut, the said rotation, the deformation due to parallel movement the The profile creation method according to claim 6 , wherein the first color gamut is deformed by applying the weight according to the distance from the boundary between the two color gamuts. The rotation, the said deformation by parallel movement, Mu said a translational movement to move the point of the white or black on the achromatic axis, the vector connecting the one and the other of said moving is white or black point The profile creation method according to claim 6 or 7 , wherein the rotation is made to coincide with the chromatic axis. The step of deforming the second color gamut is applied in the vicinity of white and black of the second color gamut and continuously suppresses deformation toward the white and black of the first color gamut. profile creation method according to any one of claims 6 to 8,. After the step of deforming the first color gamut, lightness compression is performed from the maximum brightness of the first color gamut and its predetermined vicinity to white of the second color gamut and its predetermined vicinity, and the first color lightness compression and its vicinity predetermined black from the lowest lightness and near the predetermined range, the according to any of claims 6 to 9, characterized in that the first gamut having further a step of deforming Profile creation method. An image processing device that performs conversion based on a mapping relationship including a compressed mapping from a first color gamut to a second color gamut,
Means for transforming the second color gamut by rotating and moving in parallel so that at least white and black points of the second color gamut move to points on the achromatic color axis;
Means for deforming the first color gamut by said rotating a region overlapping with the second color gamut of the first color gamut, parallel movement,
Means for forming a mapping relationship from the deformed first color gamut to the deformed second color gamut;
An image processing apparatus comprising: Means for deforming said first gamut is a further, relative to the previous SL region outside the region overlapping with the second color gamut of the first color gamut, the said rotation, the deformation due to parallel movement the The image processing apparatus according to claim 11 , wherein the first color gamut is deformed by applying a weight according to a distance from a boundary between the two color gamuts. The rotation, the said deformation by parallel movement, Mu said a translational movement to move the point of the white or black on the achromatic axis, the vector connecting the one and the other of said moving is white or black point the image processing apparatus according to claim 11 or 12, characterized in that a rotating, to match the neutral axis. The means for deforming the second color gamut is applied in the vicinity of white and black in the second color gamut, and continuously suppresses deformation toward white and black in the first color gamut. the image processing apparatus according to any one of claims 11 to 13,. After the deformation by the means for deforming the first color gamut, the lightness is compressed from the maximum brightness of the first color gamut and its predetermined neighborhood to the white of the second color gamut and its predetermined neighborhood, lightness compression and its predetermined vicinity of the black from the lowest lightness and the vicinity of the predetermined one gamut, to any one of claims 11, characterized in that had the further means for deforming the first gamut 14 The image processing apparatus described. A program that causes a computer to function as an image processing apparatus that performs conversion based on a mapping relationship including a compressed mapping from a first color gamut to a second color gamut,
Means for transforming the second color gamut by rotating and moving in parallel so that at least white and black points of the second color gamut move to points on the achromatic color axis;
Means for deforming the first color gamut by said rotating a region overlapping with the second color gamut of the first color gamut, parallel movement,
Means for forming a mapping relationship from the deformed first color gamut to the deformed second color gamut;
The program characterized by having.

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