Information processing system and program

Abstract

To suppress degradation of granularity of a printed image, as compared with the case where determination is made of the color material amount of the color material of basic and special colors corresponding to a color value uniformly irrespective of the color value which is going to be converted, when generating profile data for a printing device using the color material of a special color other than the basic CMYK colors.SOLUTION: When the Lab value which is going to be converted is outside of a color gamut expressible by basic CMYK colors and inside of a color gamut expressible by a special color P and the CMYK colors when generating an ICC profile for converting an input color value to the toner amount used for printing, an ICC profile generation unit 32 generates an ICC profile in which the toner amount of each of the CMYKP colors is determined so that the toner amount of K toner becomes zero.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure relates to an information processing system and a program. [Background technology]

[0002] Patent Document 1 discloses a color processing device that sets a color gamut in which an extraneous color component uniquely corresponds to an input color signal, generates color signal pairs that correspond to the input color signal and each extraneous color component within that color gamut, calculates each extraneous color component that corresponds to the color signal to be converted based on the color signal pairs, calculates primary color components from the calculated extraneous color components and the color signal to be converted, and converts the primary color components and extraneous color components into an output color signal.

[0003] Patent Document 2 discloses a color processing device that selects, from among combinations of M color component values ​​that can be used to obtain a target color, a combination that satisfies preset restrictions and that minimizes the sum of the M color component values, obtains combinations of M color component values ​​that are modified within a range that satisfies the restrictions for the selected combination of M color component values, and increases or decreases the number of obtained combinations of M color components depending on the color region to obtain a set of color chart colors. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-194745 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-010083 Summary of the Invention [Problem to be solved by the invention]

[0005] In a printing device that prints an image on a recording medium, the color of the formed image varies depending on the characteristics of the recording medium, environmental conditions, the characteristics of the printing device, etc. Therefore, a color measurement chart composed of multiple patch images is printed by the printing device, and profile data is generated in advance to convert the color values ​​obtained by measuring the color of each of the multiple patch images on the color measurement chart into the amounts of color materials to be used in printing. Then, in the printing process by the printing device, the generated profile data is used to determine the amount of color material for each color during printing, and printing is performed.

[0006] In recent years, in order to expand the color gamut of images printed by printing devices, printing has become commonplace, using not only the basic CMYK color materials but also special color materials such as fluorescent pink (hereinafter referred to as P) and fluorescent green (hereinafter referred to as G). The use of such special color materials allows for the reproduction of vivid colors, thereby expanding the color gamut. However, images printed using K (black) color materials generally suffer from poorer graininess than images printed using only CMY color materials. In particular, when images printed using bright color materials such as fluorescent colors are combined with K color materials, the deterioration of graininess due to the K color material becomes more noticeable compared to images printed using CMY color materials.

[0007] The object of the present disclosure is to provide an information processing system and program that, when generating profile data for a printing device that uses color materials of special colors other than the basic CMYK colors, can suppress deterioration of graininess in printed images compared to when the amounts of color materials of the basic and special colors corresponding to the color values ​​to be converted are uniformly determined regardless of the color values ​​to be converted. [Means for solving the problem]

[0008] An information processing system of a first aspect of the present disclosure includes a processor, and when generating profile data for converting input color values ​​into amounts of color materials to be used for printing, if the color value to be converted is outside the color gamut that can be expressed by the CMYK colors that are the basic colors, and is within the color gamut that can be expressed by special colors other than the basic colors and the basic colors, the processor generates profile data in which the color material amount of each color is determined so that the color material amount of the K color material is zero.

[0009] An information processing system of a second aspect of the present disclosure is the information processing system of the first aspect, wherein the processor determines the amount of color material of a predetermined special color based on first rate information indicating the proportion of the amount of color material to be used for the special color.

[0010] An information processing system of a third aspect of the present disclosure is the information processing system of the second aspect, wherein the processor determines the amounts of color materials for the remaining CMY colors excluding the amounts of color materials for the determined K color and special color, and determines the amounts of color materials for the basic color and special color corresponding to the color values.

[0011] An information processing system of a fourth aspect of the present disclosure is the information processing system of the first aspect, wherein the processor determines the amount of colorant for each color without setting the colorants for both the special color and the K color to zero when the color value to be converted is within the color gamut that can be expressed by the basic colors CMYK.

[0012] An information processing system of a fifth aspect of the present disclosure is the information processing system of the fourth aspect, wherein the processor determines the amount of color material of a predetermined special color based on first rate information indicating the proportion of the amount of color material of the special color to be used, and determines the amount of color material of the K color based on second rate information indicating the proportion of the amount of color material of a predetermined K color to be used.

[0013] An information processing system according to a sixth aspect of the present disclosure is the information processing system according to the first aspect, wherein the special color is a fluorescent color.

[0014] A program according to a seventh aspect of the present disclosure includes steps of receiving an input color value; When generating profile data for converting input color values ​​into amounts of color materials used for printing, if the color value to be converted is outside the color gamut that can be expressed by the CMYK colors that are the basic colors, and is within the color gamut that can be expressed by the basic colors and special colors other than the basic colors, the computer is caused to execute a step of generating profile data in which the color material amount of each color is determined so that the color material amount of the K color material is zero. [Effects of the Invention]

[0015] According to the information processing system of the first aspect of the present disclosure, when generating profile data for a printing device that uses color materials of special colors other than the basic CMYK colors, it is possible to suppress deterioration of graininess in the printed image compared to when the amount of color materials of the basic colors and special colors corresponding to the color values ​​to be converted is uniformly determined regardless of the color values ​​to be converted.

[0016] According to the information processing system of the second aspect of the present disclosure, it is possible to adjust the amount of color material of a special color used in printing.

[0017] According to the information processing system of the third aspect of the present disclosure, it is possible to determine the amounts of color materials for all colors, basic colors and special colors, by giving priority to determining the amounts of color materials for K color and special colors.

[0018] According to the information processing system of the fourth aspect of the present disclosure, it is possible to determine the amounts of color materials for all basic colors and special colors while using the amounts of color materials for K color and special colors.

[0019] According to the information processing system of the fifth aspect of the present disclosure, it is possible to adjust the amounts of color materials of the K color and special colors used in printing.

[0020] According to the information processing system of the sixth aspect of the present disclosure, when generating profile data for a printing device that uses fluorescent special color materials other than the basic CMYK colors, it is possible to suppress deterioration of graininess in the printed image compared to when the amounts of color materials for the basic and special colors that correspond to the color values ​​to be converted are uniformly determined regardless of the color values ​​to be converted.

[0021] According to the program of the seventh aspect of the present disclosure, when generating profile data for a printing device that uses color materials of special colors other than the basic CMYK colors, it is possible to suppress deterioration of graininess in the printed image compared to when the amount of color materials of the basic colors and special colors corresponding to the color values ​​to be converted is uniformly determined regardless of the color values ​​to be converted. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a diagram illustrating a system configuration of an image forming system according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a cross-sectional view showing the structure of the image forming apparatus 20 shown in FIG. [Figure 3] 10A and 10B are diagrams for explaining differences in image quality depending on combinations of toner amounts when reproducing the same color. [Figure 4] 1 is a diagram illustrating a hardware configuration of a terminal device 10 in an image forming system according to an embodiment of the present disclosure. [Figure 5] 1 is a block diagram showing a functional configuration of a terminal device 10 in an image forming system according to an embodiment of the present disclosure. [Figure 6] FIG. 10 is a diagram showing how the ICC profile generation unit 32 generates an ICC profile in which the toner amount of each CMYKP color is determined so that the toner amount of K toner is zero when the Lab value to be converted is outside the color gamut that can be expressed by the basic CMYK colors. [Figure 7] 10 is a diagram showing an example of a setting screen when a generation condition receiving unit 31 receives the generation conditions of an ICC profile. FIG. [Figure 8]10 is a flowchart for explaining the overall operation of an ICC profile generation process in an ICC profile generation unit 32. [Figure 9] 9 is a flowchart for explaining details of the process of step S103 described in the flowchart of FIG. 8. [Figure 10] 10A and 10B are diagrams illustrating a method for determining the toner amounts of K toner and P toner when the Lab value to be converted is within the range of the color gamut that can be expressed by CMYK colors. [Figure 11] 10A and 10B are diagrams illustrating a method for determining the toner amounts of K toner and P toner when the Lab value to be converted is outside the range of the color gamut that can be expressed by CMYK colors. DETAILED DESCRIPTION OF THE INVENTION

[0023] Next, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0024] FIG. 1 is a diagram showing a system configuration of an image forming system according to an embodiment of the present disclosure.

[0025] 1, the image forming system of this embodiment is composed of an image forming apparatus 20 and a terminal device 10 interconnected by a network 30, and a colorimeter 40 connected to the terminal device 10. The image forming apparatus 20 is, for example, a so-called production printer used for commercial printing, and has the functionality to perform high-quality, high-speed printing processing.

[0026] Next, the structure of the image forming apparatus 20 shown in FIG. 1 is shown in FIG.

[0027] 2, the image forming device 20 has six image forming units 21. These six image forming units 21 are configured to form images on a recording medium using toners of the basic colors of yellow (Y), magenta (M), cyan (C), and black (K), respectively, and toners of two special colors (fluorescent pink (P) and fluorescent green (G)).

[0028] The image forming unit 21 is composed of a photosensitive drum, a charging device that uniformly charges the surface of the photosensitive drum, a developing device that develops the electrostatic latent image formed on the photosensitive drum, and a cleaning device. The photosensitive drum is a cylindrical image carrier that holds a toner image (developer image), and is uniformly charged by the charging device, and an electrostatic latent image is formed on the photosensitive drum by laser light irradiated by an optical scanning device 24. The electrostatic latent image formed on the photosensitive drum is developed with toner by the developing device and transferred to the intermediate transfer belt 22. After the toner image transfer process, residual toner and paper dust remaining on the photosensitive drum are removed by a cleaning device.

[0029] The image forming units 21 are provided adjacent to an intermediate transfer belt 22. The intermediate transfer belt 22 rotates in the direction of arrow A in FIG. 2. Primary transfer rolls 23 are disposed opposite the photosensitive drums across the intermediate transfer belt 22. The primary transfer rolls 23 are provided to transfer the toner images of each color formed on the photosensitive drums onto the intermediate transfer belt 22.

[0030] A transport path 29 for transporting the recording medium is formed below the intermediate transfer belt 22. The transport path 29 is provided with a plurality of transport rolls that transport the recording medium from the inlet 25 to the outlet 28. The transport path 29 also includes a secondary transfer device 26 that performs a second transfer of a toner image, which has been primarily transferred from the photosensitive drum to the intermediate transfer belt 22, onto the recording medium transported along the transport path 29. A fixing device 27 is provided downstream of the secondary transfer device 26 in the recording medium transport direction. The fixing device 27 is a device for fixing an image formed by the plurality of image forming units 21 onto the recording medium by heating it, and fixes the image on the recording medium onto which the toner image has been transferred onto the recording medium by heat and pressure. The recording medium with the image fixed by the fixing device 27 is discharged from the outlet 28.

[0031] In the image forming device 20 that prints an image on printing paper, the color of the printed image varies depending on the characteristics of the printing paper, environmental conditions, and individual differences in the image forming device 20. Therefore, in order to maintain color consistency between printing papers and to unify color reproduction between models, conversion data called an ICC (International Color Consortium) profile is generated in advance for each model, and the amount of toner for each color when printing is determined based on this ICC profile.

[0032] Here, color values ​​that are independent of device characteristics are generally defined by the International Commission on Illumination (CIE) as L * a * b * In the following explanation, the color space is expressed as L * a * b * The values ​​in the color space are simply referred to as Lab values. Therefore, an ICC profile is profile data that stores, in the form of a lookup table, information on which colors of toner should be combined and in what amounts for printing in order to reproduce the Lab color values ​​expressed in a certain Lab color space.

[0033] To generate such an ICC profile, the image forming device 20 first prints a color measurement chart 50 composed of multiple patch images. The color values ​​of each patch image on the printed color measurement chart 50 are then measured using the colorimeter 40, and the resulting color values ​​are input to the terminal device 10. The terminal device 10 then generates an ICC profile by determining a combination of toner amounts that will convert the input color values ​​to target color values, and stores the generated ICC profile in the image forming device 20. The image forming device 20 then uses the stored ICC profile to determine the toner amounts for each color when printing, and executes the printing process, thereby resulting in the color values ​​of the printed image approaching the target color values. Here, "input color values" refer to Lab color values ​​to be input. However, some ICC profiles may use CMYK color values ​​or RGB color values, and are not limited to Lab color values. Furthermore, "target color values" refer to the input color values ​​converted into Lab color values ​​that can be output by a printing press. Furthermore, the combination of toner amounts refers to the CMYK color values ​​that can reproduce the target color values, calculated from the pair of CMYKN of the patch and the measured Lab color values.

[0034] As described above, the image forming device 20 prints using two special color toners, PG, in addition to the normal color toners CMYK. Therefore, the terminal device 10 needs to generate an ICC profile that can determine the amount of toner needed for each of the normal color toners and the special color toners in order to reproduce a certain Lab value.

[0035] However, it is not possible to uniquely determine an ICC profile for converting three-dimensional data, such as Lab values, into five-dimensional data, such as CMYKPG. Even if the reproduced Lab values ​​are the same, the quality of the printed image will change depending on the amount of K toner and the amount of special color PG toner, so it is necessary to determine the appropriate combination from the vast number of combinations of toner amounts for each color of CMYKPG toner.

[0036] Here, the ratio of the amount of special color toner actually used to the amount of toner required to reproduce a certain Lab value is called the CCR (Chromatic Component Replacement) rate.Similarly, the ratio of the amount of K toner actually used to the amount of toner required to reproduce a certain Lab value is called the GCR (Gray Component Replacement) rate.

[0037] For example, for simplicity of explanation, the following description will be given of a case where printing is performed using P (fluorescent pink) toner as a special color toner in addition to normal color CMYK toner.

[0038] Even if the special color toner is only one color, P toner, determining an ICC profile requires determining the toner amounts of five colors in total (P in addition to the four colors of CMYK) to reproduce a certain Lab value. Therefore, the toner amount of P toner is determined based on a preset CCR rate, and the toner amount of K toner is determined based on a preset GCR rate. If the toner amounts of the remaining three colors, CMY, are then determined after the toner amounts of K and P toner have been determined, a unique solution for converting Lab values, which are three-dimensional data, into CMY values, which are three-dimensional data, can be determined.

[0039] However, even when reproducing colors with the same Lab value, the print quality will differ depending on the combination of toner amounts for each color. Figure 3 shows the difference in image quality depending on the combination of toner amounts when reproducing the same color. Figure 3 shows an example of a combination of CMYKP toner amounts when reproducing an image of the same color, pink, using P toner.

[0040] Generally, images printed using K toner have poorer graininess than images printed using only CMY toner. In particular, images printed using P toner, which is a bright color material such as a fluorescent color, have more pronounced graininess than images printed using only CMY toner. Furthermore, fluorescent toners such as P toner have poorer light resistance than standard CMYK toners. Here, an image with poor graininess refers to an image in which the printed image has noticeable roughness, meaning an image with an uneven surface.

[0041] Therefore, as shown in Figure 3, if the CCR rate is set high and the GCR rate is set low to reduce the amount of K toner and increase the amount of P toner, an image with good graininess can be obtained, but lightfastness will be poor. Alternatively, if the GCR rate is left unchanged and the CCR rate is set to an intermediate value to reduce the amount of P toner while keeping the amount of K toner the same, lightfastness will be improved. Furthermore, if the CCR rate is set low and the GCR rate is set high to increase the amount of K toner and decrease the amount of P toner, an image with good lightfastness but poor graininess will be obtained.

[0042] Therefore, in the terminal device 10 of this embodiment, by generating an ICC profile using the method described below, when generating ICC profile data for the image forming device 20 that uses special color toner such as P toner other than the basic CMYK colors, deterioration of the graininess of the printed image is suppressed compared to when the toner amounts of CMYK colors and P toner corresponding to the color values ​​to be converted are uniformly determined regardless of the color values ​​to be converted.

[0043] Next, the hardware configuration of the terminal device 10 in the image forming system of this embodiment is shown in FIG.

[0044] 4, the terminal device 10 has a CPU 11, a memory 12, a storage device 13 such as a hard disk drive, a communication interface (abbreviated as IF) 14 for transmitting and receiving data to and from external devices via a network 30, and a user interface (abbreviated as UI) device 15 including a touch panel or liquid crystal display and a keyboard. These components are connected to each other via a control bus 16.

[0045] The CPU 11 is a processor that controls the operation of the terminal device 10 by executing predetermined processes based on a control program stored in the memory 12 or the storage device 13. In the present embodiment, the CPU 11 is described as reading and executing the control program stored in the memory 12 or the storage device 13, but this is not limiting. The control program may be provided in a form recorded on a computer-readable recording medium. For example, the program may be provided in a form recorded on an optical disc such as a CD (Compact Disc)-ROM or a DVD (Digital Versatile Disc)-ROM, or in a form recorded on a semiconductor memory such as a USB (Universal Serial Bus) memory or a memory card. The control program may also be acquired from an external device via a communication line connected to the communication interface 14. The control program may be provided as standalone application software, or may be incorporated into the software of each device of the terminal device 10 as a function of the device.

[0046] FIG. 5 is a block diagram showing the functional configuration of the terminal device 10 realized by executing the above control program.

[0047] As shown in Fig. 5, the terminal device 10 of this embodiment includes a generation condition receiving unit 31, an ICC profile generation unit 32, an ICC profile storage unit 33, and an ICC profile transfer unit 34. Note that Fig. 4 shows only the part of the functional configuration of the terminal device 10 that is related to the generation of an ICC profile.

[0048] The generation condition receiving unit 31 receives various conditions for generating an ICC profile, specifically, information such as the CCR rate and GCR rate.

[0049] The ICC profile generation unit 32 generates an ICC profile based on the colorimetric values ​​of the patch image of the color measurement chart 50 measured by the colorimeter 40 and the generation conditions accepted by the generation condition acceptance unit 31, and stores the ICC profile in the ICC profile storage unit 33.

[0050] Specifically, when the ICC profile generation unit 32 generates an ICC profile that converts the input color values ​​of the color measurement chart 50 into the toner amounts used for printing, if the Lab values ​​to be converted are outside the color gamut that can be expressed by the basic colors CMYK, but are within the color gamut that can be expressed by the special color P and CMYK, the ICC profile generation unit 32 generates an ICC profile in which the toner amounts of each of the CMYKP colors are determined so that the toner amount of K toner is zero.

[0051] Then, the ICC profile generating unit 32 determines the amount of P toner based on the CCR rate, which is preset rate information indicating the proportion of the amount of P toner, which is a special color, to be used.

[0052] Here, if the color value to be converted is within the color gamut that can be expressed by the basic CMYK colors, the ICC profile generation unit 32 determines the amount of color material for each color without setting the color materials for both the special color and the K color to zero.

[0053] Specifically, the ICC profile generation unit 32 determines the amount of P toner based on the CCR rate, and determines the amount of K toner based on the GCR rate, which is rate information indicating the proportion of the predetermined K color toner amount used.

[0054] Then, after determining the toner amounts of P toner and K toner using the above-described method, the ICC profile generation unit 32 determines the toner amounts of the remaining CMY toners excluding the determined toner amounts of K toner and P toner, and determines the toner amounts of CMYK toner and P toner corresponding to the Lab values.

[0055] The ICC profile transfer unit 34 transfers the ICC profile stored in the ICC profile storage unit 33 to the image forming apparatus 20 .

[0056] In this embodiment, we will explain the case where the special color colorant is fluorescent P toner, but an ICC profile can also be generated using a similar method when the special color colorant is fluorescent G toner.

[0057] Next, Figure 6 shows how the ICC profile generation unit 32 generates an ICC profile in which the toner amount of each CMYKP color is determined so that the toner amount of K toner is zero when the Lab value to be converted is outside the color gamut that can be expressed by the basic CMYK colors.

[0058] 6 shows how the color gamut that can be expressed by CMYK toners is expanded by using basic color toners. The shaded area in FIG. 6 indicates the color gamut expanded by using special color toners. If the Lab value to be converted is included in the color gamut expanded by using such special color toners, the ICC profile generation unit 32 sets the toner amount of K toner to zero regardless of the set GCR rate value, and determines the toner amounts of CMYKP toners.

[0059] 6 shows how a combination of the toner amounts of each color is determined, with the toner amount of K toner set to 0, such as CMYKP=(0, 20, 10, 0, 50), even when a certain Lab value included in the color gamut expanded by the special color toner can be expressed as CMYKP=(0, 10, 0, 10, 50) where the toner amount of K toner is set to 0. In this way, the toner amount of K toner is set to zero in a color gamut that uses P toner, a special color toner, because combining both K toner and P toner worsens the graininess of the printed image.

[0060] Next, an example of a setting screen when the generation condition receiving unit 31 receives the generation conditions of the ICC profile is shown in FIG.

[0061] 7, a slide bar can be used to set whether to increase or decrease the amount of special color toner. When the slide bar is used to increase the amount of special color toner, the CCR rate increases, and when the slide bar is used to decrease the amount of special color toner, the CCR rate decreases.

[0062] 7, a slide bar can be used to set whether to increase or decrease the amount of K toner. When the slide bar is used to increase the amount of K toner, the GCR rate increases, and when the slide bar is used to decrease the amount of K toner, the GCR rate decreases.

[0063] In this way, the generation condition receiving unit 31 receives the settings of the CCR rate and the GCR rate from the user.

[0064] In the example settings screen shown in Figure 7, a checkbox next to the words "Do not include K in areas enlarged by special colors" can be selected. If this checkbox is selected, processing is performed to set the amount of K toner to zero if the Lab value to be converted is included in the color gamut enlarged by special color toner.

[0065] Next, the operation of the ICC profile generating unit 32 in the terminal device 10 of this embodiment will be described in detail with reference to the drawings.

[0066] First, the overall operation of the ICC profile generation process in the ICC profile generation unit 32 will be described with reference to the flowchart in FIG.

[0067] First, in step S101, the ICC profile generator 32 corrects the input color values ​​so that they fall within the color gamut that can be represented by the image forming device 20.

[0068] Then, in step S102, the ICC profile generating unit 32 selects one Lab value from the input color values.

[0069] Next, in step S103, the ICC profile generating unit 32 determines the toner amount of K toner and the toner amount of P toner for the selected Lab value.

[0070] Furthermore, in step S104, the ICC profile generation unit 32 determines the toner amounts of CMY toners for the selected Lab values. At this stage, the toner amounts of K toner and P toner have already been determined, so it is possible to uniquely determine a solution by simply converting the three-dimensional data of Lab values ​​into three-dimensional data of CMY.

[0071] Finally, in step S105, the ICC profile generation unit 32 determines whether or not selection of all input color values ​​in the colorimetric data has been completed. If it is determined in step S105 that selection of all input color values ​​in the colorimetric data has not been completed, the ICC profile generation unit 32 returns to the processing of step S102. On the other hand, if it is determined in step S105 that selection of all input color values ​​has been completed, the ICC profile generation unit 32 ends the processing.

[0072] Next, details of the process of step S103, which is the process for determining the toner amounts of K toner and P toner described in the flowchart of FIG. 8, will be described with reference to the flowchart of FIG.

[0073] First, in step S201, the ICC profile generating unit 32 determines whether the Lab values ​​to be converted are within the range of the CMYK color gamut, that is, whether they are within the range of the color gamut expanded by the special toner.

[0074] Then, if it is determined in step S201 that the Lab value to be converted is within the range of the CMYK color gamut, the ICC profile generation unit 32 determines in step S202 the maximum value (hereinafter abbreviated as maximum K amount) and minimum value (hereinafter abbreviated as minimum K amount) of the toner amount of K toner among the combinations of toner amounts that can represent the Lab value to be converted using CMYKP toner.

[0075] Then, in step S203, the ICC profile generation unit 32 determines the toner amount of K toner using the GCR rate between the maximum K amount and the minimum K amount. Specifically, when the GCR rate is 100%, the ICC profile generation unit 32 determines the maximum K amount as the final toner amount of K toner, and when the GCR rate is 0%, the ICC profile generation unit 32 determines the minimum K amount as the final toner amount of K toner.

[0076] Next, in step S204, the ICC profile generation unit 32 determines the maximum value (hereinafter abbreviated as maximum P amount) and minimum value (hereinafter abbreviated as minimum P amount) of the toner amount of P toner among the combinations of toner amounts that can be expressed using CMYKP toner to convert the Lab value to be converted.

[0077] Then, in step S205, the ICC profile generation unit 32 determines the toner amount of P toner using a CCR rate between the maximum P amount and the minimum P amount. Specifically, when the CCR rate is 100%, the ICC profile generation unit 32 determines the maximum P amount as the final toner amount of P toner, and when the CCR rate is 0%, the ICC profile generation unit 32 determines the minimum P amount as the final toner amount of P toner.

[0078] FIG. 10 shows a method for determining the toner amounts of K toner and P toner when the Lab value to be converted is within the range of the color gamut that can be expressed by CMYK colors.

[0079] The shaded area in the graph of FIG. 10 indicates the range of the K toner amount and the P toner amount that can reproduce the Lab value to be converted.

[0080] The ICC profile generation unit 32 determines the toner amount of K toner based on the GCR rate within the range from the minimum K amount to the maximum K amount. The toner amount of K toner determined in this manner is shown as GCR-K in FIG.

[0081] Similarly, the ICC profile generation unit 32 determines the toner amount of P toner based on the CCR rate within the range from the minimum amount of P to the maximum amount of P. The toner amount of P toner determined in this manner is shown as CCR-P in FIG.

[0082] The GCR-K and CCR-P determined in this way become the final toner amounts of K toner and P toner, respectively.

[0083] Next, if it is determined in step S201 that the Lab value to be converted is outside the range of the CMYK color gamut, the ICC profile generating unit 32 sets the toner amount of K toner to zero in step S206.

[0084] Next, in step S207, the ICC profile generating unit 32 obtains the maximum P amount and the minimum P amount for the Lab values ​​to be converted.

[0085] Then, in step S208, the ICC profile generating unit 32 determines the toner amount of P toner using the CCR rate between the maximum P amount and the minimum P amount.

[0086] FIG. 11 shows a method for determining the toner amounts of K toner and P toner when the Lab value to be converted is outside the range of the color gamut that can be expressed by CMYK colors.

[0087] As in FIG. 10, the hatched areas in the graph of FIG. 11 indicate the ranges of the K toner amount and the P toner amount that can reproduce the Lab values ​​to be converted.

[0088] In this case, the ICC profile generating unit 32 determines the toner amount of K toner to be zero regardless of the set GCR rate.

[0089] Then, for the toner amount of P toner, the ICC profile generation unit 32 determines the toner amount of P toner based on the CCR rate within the range of the minimum P amount to the maximum P amount. The toner amount of P toner determined in this way is also shown as CCR-P in FIG.

[0090] In this way, the toner amount of K toner is determined to be zero, and CCR-P is determined as the final toner amount of P toner.

[0091] In each of the above embodiments, the term "processor" refers to a processor in a broad sense, and includes general-purpose processors (e.g., CPU: Central Processing Unit, etc.) and dedicated processors (e.g., GPU: Graphics Processing Unit, ASIC: Application Specific Integrated Circuit, FPGA: Field Programmable Gate Array, programmable logic device, etc.).

[0092] Furthermore, the operations of the processor in each of the above embodiments may be performed not only by a single processor but also by multiple processors located at physically separate locations working together. Furthermore, the order of the operations of the processor is not limited to the order described in each of the above embodiments and may be changed as appropriate.

[0093] In this embodiment, the term "system" includes both a system made up of multiple devices and a system made up of a single device.

[0094] [Variations] In the above embodiment, an example of generating an ICC profile when printing using fluorescent color toner was described, but the present disclosure is not limited to this example, and can be similarly applied to the case of generating an ICC profile when printing using special color toner other than fluorescent color toner.

[0095] [Note] Preferred embodiments of the present disclosure will be described below.

[0096] (((1))) a processor; The processor: When generating profile data for converting input color values ​​into amounts of color materials used for printing, if the color value to be converted is outside the color gamut that can be expressed by the CMYK colors that are the basic colors, and is within the color gamut that can be expressed by special colors other than the basic colors and the basic colors, generate profile data in which the color material amount of each color is determined so that the color material amount of the K color material is zero. Information processing system.

[0097] (((2))) the processor determines the amount of the colorant of the special color based on first rate information indicating a rate at which the amount of the colorant of the special color is used, the first rate information indicating a rate at which the amount of the colorant of the special color is used being set in advance; The information processing system according to (((1))).

[0098] (((3))) the processor determines the amounts of colorants of the remaining CMY colors excluding the amounts of colorants of the determined K color and special color, and determines the amounts of colorants of the basic colors and special colors corresponding to the color values; The information processing system according to (((2))).

[0099] (((4))) When the color value to be converted is within a color gamut that can be expressed by the CMYK colors that are the basic colors, the processor determines the amount of color material for each color without setting the color materials for both the special color and the K color to zero. An information processing system according to any one of (((1))) to (((3))).

[0100] (((5))) the processor determines the amount of color material of the special color based on first rate information indicating a ratio of a color material amount of the special color to be used, and determines the amount of color material of the K color based on second rate information indicating a ratio of a color material amount of the K color to be used, The information processing system according to (((4))).

[0101] (((6))) The special color is a fluorescent color. An information processing system according to any one of (((1))) to (((5))).

[0102] (((7))) accepting an input color value; a step of generating profile data for converting input color values ​​into amounts of color materials used for printing, in which, when the color value to be converted is outside the color gamut that can be expressed by the CMYK colors that are the basic colors, and is within the color gamut that can be expressed by the basic colors and special colors other than the basic colors, generating profile data in which the color material amount of each color is determined so that the color material amount of the K color material is zero; A program that causes a computer to execute the following.

[0103] The effects of the configuration described above will be described below.

[0104] According to the information processing system (((1))), when generating profile data for a printing device that uses color materials of special colors other than the basic CMYK colors, it is possible to suppress deterioration of graininess in the printed image compared to when the amounts of color materials of the basic colors and special colors that correspond to the color values ​​to be converted are uniformly determined regardless of the color values ​​to be converted.

[0105] According to the information processing system (((2))), it is possible to adjust the amount of color material of a special color used in printing.

[0106] According to the information processing system (((3))), it is possible to determine the amounts of color materials for all basic colors and special colors by giving priority to the amounts of color materials for K color and special colors.

[0107] According to the information processing system (((4))), it is possible to determine the amounts of color materials for all basic colors and special colors while using the amounts of color materials for K color and special colors.

[0108] According to the information processing system (((5))), it is possible to adjust the amount of color material for the K color and special color used in printing.

[0109] According to the information processing system (((6))), when generating profile data for a printing device that uses fluorescent special color materials other than the basic CMYK colors, it is possible to suppress deterioration of graininess in the printed image compared to when the amounts of color materials for the basic and special colors that correspond to the color values ​​to be converted are uniformly determined regardless of the color values ​​to be converted.

[0110] According to the program (((7))), when generating profile data for a printing device that uses color materials of special colors other than the basic CMYK colors, it is possible to suppress deterioration of graininess in the printed image compared to when the amounts of color materials of the basic colors and special colors that correspond to the color values ​​to be converted are uniformly determined regardless of the color values ​​to be converted. [Explanation of symbols]

[0111] 10 Terminal Equipment 11 CPU 12 Memory 13 Storage device 14 Communication Interface 15 User Interface Device 16 Control Bus 20 Image forming device 21 Image forming unit 22 Intermediate transfer belt 23 Primary transfer roll 24 Optical scanning device 25 Loading entrance 26 Secondary transfer device 27 Fixing device 28 Outlet 29 Transport Path 30 Network 31 Generation condition reception unit 32 ICC Profile Generation Unit 33 ICC program file storage 34 ICC Profile Transfer Section 40 Colorimeter 50 Color measurement chart

Claims

1. a processor; The processor: When generating profile data for converting input color values ​​into amounts of color materials used in printing, if the color value to be converted is outside the color gamut that can be expressed by the CMYK colors that are the basic colors, and is within the color gamut that can be expressed by special colors other than the basic colors and the basic colors, profile data is generated in which the color material amount of each color is determined so that the color material amount of the K color material is zero. Information processing system.

2. the processor determines the amount of the colorant of the special color based on first rate information indicating a rate at which the amount of the colorant of the special color is used, the rate being set in advance; The information processing system according to claim 1 .

3. the processor determines the amounts of colorants of the remaining CMY colors excluding the amounts of colorants of the determined K color and special color, and determines the amounts of colorants of the basic color and special color corresponding to the color values; The information processing system according to claim 2 .

4. When the color value to be converted is within a color gamut that can be expressed by the CMYK colors that are the basic colors, the processor determines the amount of color material for each color without setting the color materials for both the special color and the K color to zero. The information processing system according to claim 1 .

5. the processor determines the amount of color material of the special color based on first rate information indicating a ratio of a color material amount of the special color to be used, and determines the amount of color material of the K color based on second rate information indicating a ratio of a color material amount of the K color to be used, The information processing system according to claim 4 .

6. The special color is a fluorescent color. The information processing system according to claim 1 .

7. accepting an input color value; a step of generating profile data for converting input color values ​​into amounts of color materials used in printing, in which, when the color value to be converted is outside the color gamut that can be expressed by the CMYK colors that are the basic colors, and is within the color gamut that can be expressed by the basic colors and special colors other than the basic colors, generating profile data in which the color material amount of each color is determined so that the color material amount of the K color material is zero; A program that causes a computer to execute the following.

Images