Method for generating proof image data, proof image data generating device, and computer program

Abstract

To provide a technique to reflect the influence of bleeding on proof image data.SOLUTION: A method for generating proof image data includes: (a) a step of acquiring basic proof image data for reproducing, with a proof output device, the color of a print printed on a print medium by using a printer; and (b) a step of applying bleeding adding processing to the basic proof image data by using a bleeding parameter representing a bleeding state of ink in the print to generate bleeding added proof image data simulating the bleeding state.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a method for creating proof image data, a proof image data creation device, and a computer program. [Background technology]

[0002] Patent Document 1 discloses a method for creating a proof image for proofreading a printed matter. In this conventional technology, a proof image is created by correcting an image based on the density distribution in two-dimensional space on the surface of a printed matter printed at 100% density on a printing medium. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 09-270930 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the inventors of the present disclosure have discovered that the impact of ink bleeding is significant in prints printed on certain print media, such as fabric, and that the impact of bleeding should be taken into consideration when creating a proof image. Bleeding occurs when ink that has landed on the print medium spreads, mixes with adjacent inks, or flows due to the unevenness of the print medium before soaking into the print medium. Therefore, in order to faithfully reproduce the state of the print, it is desirable to reflect the impact of bleeding in the proof image data. [Means for solving the problem]

[0005] According to a first aspect of the present disclosure, there is provided a method for creating proof image data, the method including: (a) acquiring basic proof image data for reproducing, with a proof output device, the colors of a printed matter printed on a printing medium using a printing press; and (b) applying a bleeding process to the basic proof image data using bleeding parameters representing a bleeding state of ink in the printed matter, thereby creating bleeding-added proof image data that simulates the bleeding state.

[0006] According to a second aspect of the present disclosure, there is provided a proof image data creation device including: a basic proof image acquisition unit that acquires basic proof image data for reproducing, by a proof output device, the colors of a printed matter printed on a printing medium using a printing press; and a bleed processing unit that applies a bleed addition process to the basic proof image data using bleed parameters that represent the bleed state of ink in the printed matter, thereby creating bleed-added proof image data that simulates the bleed state.

[0007] According to a third aspect of the present disclosure, there is provided a computer program for creating proof image data, which causes a computer to execute (a) a process for acquiring basic proof image data for reproducing, by a proof output device, the colors of a printed matter printed on a printing medium using a printing press, and (b) a process for creating bleeding-added proof image data that simulates the bleeding state by applying a bleeding addition process to the basic proof image data using bleeding parameters that represent the bleeding state of ink in the printed matter. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is an explanatory diagram showing a printing system for proofreading a printed material. [Figure 2] FIG. 1 is a block diagram showing the configuration of a proof image data creation device. [Figure 3] FIG. 4 is an explanatory diagram showing the flow of proof image creation processing. [Figure 4]FIG. 10 is an explanatory diagram showing an example of a basic proof image. [Figure 5] FIG. 10 is an explanatory diagram showing an example of texture information. [Figure 6] FIG. 10 is an explanatory diagram showing an example of a bleeding parameter setting screen. [Figure 7] FIG. 10 is an explanatory diagram showing an example of a bleeding process in bleeding mode M1. [Figure 8] FIG. 10 is an explanatory diagram showing an example of a bleeding process in bleeding mode M2. [Figure 9] FIG. 10 is an explanatory diagram showing another example of the bleeding process in the bleeding mode M2. [Figure 10] FIG. 10 is an explanatory diagram showing an example of a bleeding process using a bleeding mode M2a. [Figure 11] FIG. 10 is an explanatory diagram showing an example of a bleeding process in bleeding mode M3. [Figure 12] FIG. 10 is an explanatory diagram showing an example of a bleeding process in bleeding mode M4. [Figure 13] 10 is a flowchart showing the procedure of a process for creating proof image data. [Figure 14] 10 is a flowchart showing the detailed procedure of a bleeding process. DETAILED DESCRIPTION OF THE INVENTION

[0009] FIG. 1 is an explanatory diagram showing a printing system 500 for proofing printed materials. This printing system 500 includes a printing machine 300 that prints printed materials PM according to input image data IM, a proof image data creation device 100 that creates proof image data using the input image data IM, and a proof printing device 200. Proofing can be performed in two ways: hard proofing, in which a proof print HP is printed using the proof printing device 200, and soft proofing, in which a proof image SP is displayed on a display device 150 according to the proof image data. In hard proofing, the proof printing device 200 corresponds to the "proof output device," while in soft proofing, the display device 150 corresponds to the "proof output device." The image output from the proof output device is also called the "output image." In hard proofing, the proof print HP corresponds to the "output image," while in soft proofing, the proof image SP corresponds to the "output image."

[0010] The proof image data creation device 100 is configured to be able to perform at least one of hard proofing and soft proofing. In hard proofing, the proof printing device 200 prints a proof HP according to the proof image data created by the proof image data creation device 100. If the proof printing device 200 is an inkjet printer, the proof image data creation device 100 applies color conversion processing and halftone processing to the proof image data to create dot data for printing, and supplies this dot data to the proof printing device 200 to print the proof HP. In soft proofing, a proof image SP is displayed on the display device 150 according to the proof image data created by the proof image data creation device 100. The present disclosure is applicable to both hard proofing and soft proofing.

[0011] The printing machine 300 is, for example, a textile printing machine that performs textile printing on a printing medium made of cloth. The print PM printed on a printing medium made of cloth is significantly affected by ink bleeding. The proof image data creation device 100 creates proof image data that incorporates bleeding in order to faithfully reproduce the state of the print PM. However, the present disclosure is also applicable to cases where the printing machine 300 prints on a printing medium other than cloth.

[0012] 2 is a block diagram showing the configuration of the proof image data creation device 100. The proof image data creation device 100 is a computer including a CPU 50, a storage unit 60, and an input / output interface 70. The CPU 50, the storage unit 60, and the input / output interface 70 are connected via an internal bus to enable bidirectional communication.

[0013] The CPU 50 executes a proof image creation program 61 stored in advance in the storage unit 60, thereby functioning as a basic proof image acquisition unit 120, a bleed processing unit 130, and a texture adding unit 140. The bleed processing unit 130 includes an edge extraction unit 131 and a bleed adding unit 132. At least a part of the functions of these units 120 to 140 may be realized by a hardware circuit, or may be realized on the cloud.

[0014] The input / output interface 70 is connected by wire or wirelessly to the display device 150 and the proof printing device 200. The display device 150 is used to display windows and proof images, which will be described later.

[0015] FIG. 3 is an explanatory diagram showing the flow of the proof image creation process. The basic proof image acquisition unit 120 acquires basic proof image data BPF. The basic proof image data BPF is data that reflects the differences in color reproduction between the printing press 300 and the proof output device in the input image data IM. In other words, the basic proof image data BPF is data for reproducing the colors of the printed matter printed on the printing medium using the printing press 300 in the proof output device. However, the basic proof image data BPF does not reflect ink bleeding or texture information of the printing medium. In this embodiment, the basic proof image acquisition unit 120 creates basic proof image data BPF from the input image data IM. This creation process uses various ICC profiles, such as the input profile of the input image data IM, the device profile and media profile of the proof output device, and the media profile of the printing press 300 that will print the printed matter PM. However, if the basic proof image data BPF has already been created, the basic proof image acquisition unit 120 may acquire the basic proof image data BPF by reading it out from the storage unit 60.

[0016] Any method can be used to create the basic proof image data BPF. For example, the method described in Japanese Patent Application No. 2022-194704, filed by the applicant of the present disclosure, may be used. In this method, the following processes are executed in sequence. <Process P1> The first image data is obtained by converting the color space of the input image data IM into the output color space of the printing machine 300 using an ICC profile. <Process P2> The first image data is converted to a representation in the profile connection space using a first conversion table, and white point conversion is performed using information on how the background color area in the printed matter PM, where no image is formed, appears in a predetermined observation environment, thereby obtaining second image data represented in the absolute XYZ color space. <Process P3> Using a second conversion table, the second image data is converted into converted image data expressed in the output color space of the proof output device. The output color space of the proof output device is, for example, the CMYK color space or the RGB color space. The second image data or the converted image data can be used as basic proof image data BPF.

[0017] Note that a proof image may also be created using the above-mentioned conventional technique (JP 09-270930 A) or the method described in JP 2006-30277 A. When using the above-mentioned conventional technique, basic proof image data BPF that does not reflect texture can be created by performing processing that omits the first and second corrections related to the texture of the paper.

[0018] In this embodiment, the basic proof image data BPF is assumed to be expressed in the L*a*b* color space. When basic proof image data expressed in the output color space of the proof output device is created using the various methods described above, the output color space of the proof output device can be converted to the L*a*b* color space using the output profile of the proof output device. Furthermore, when using the method described in the above-mentioned Japanese Patent Application No. 2022-194704, the color space of the second image data expressed in the absolute XYZ color space may be converted to the L*a*b* color space.

[0019] 4 is an explanatory diagram showing an example of a basic proof image represented by the basic proof image data BPF. The basic proof image data BPF represents a basic proof image in which a dark-colored ink-discharged area IP is printed on a background BG. In this embodiment, the basic proof image data BPF is expressed in the L*a*b* color space. For example, the background BG is a white area with L*=90, and the ink-discharged area IP is a gray area with L*=25.

[0020] 3, the bleed processing unit 130 applies bleed processing to the basic proof image data BPF to create bleed-added proof image data ZPF that simulates a bleed state. The bleed processing unit 130 includes an edge extraction unit 131 and a bleed adding unit 132.

[0021] The edge extraction unit 131 generates edge data ED representing the edges by extracting edges of the basic proof image represented by the basic proof image data BPF. As the edge extraction process, for example, one or more of the following processes can be used.

[0022] <Edge extraction processing using pixel value differences> The brightness difference or color difference between adjacent pixels in the basic proof image is calculated, and pixels with a brightness difference or color difference greater than or equal to a threshold are extracted as edge pixels. In edge extraction processing using brightness difference, the difference in brightness L* between the basic proof image and a shifted image obtained by shifting the basic proof image by one pixel is calculated, and pixels with an absolute value of the brightness difference greater than or equal to a threshold are determined as candidate pixels. If the brightness difference is positive, the candidate pixel is extracted as an edge pixel. On the other hand, if the brightness difference is negative, a pixel shifted one pixel from the candidate pixel in the direction opposite to the shift direction is extracted as an edge pixel. This edge extraction processing is performed for both cases where pixels are shifted vertically and horizontally. The same is true for edge extraction processing using color difference.

[0023] <Edge extraction processing using an edge extraction filter> An edge extraction filter is used to extract edge pixels contained in the basic proof image.

[0024] <Edge extraction processing for characters> If the basic proof image data BPF includes character data representing characters, pixels that form the outline of the characters are extracted as edge pixels.

[0025] In the example of FIG. 4, all pixels that make up the dark-color ink ejection area IP are extracted as edge pixels.

[0026] The bleeding imparting unit 132 applies a bleeding imparting process to the basic proof image data BPF using bleeding parameters ZP that represent the ink bleeding state in the printed matter PM printed by the printing press 300, thereby creating bleeding imparted proof image data ZPF that simulates the bleeding state. The bleeding parameters ZP are set by the user using a bleeding parameter setting screen, which will be described later. In addition to the bleeding parameters ZP, the bleeding imparting process also references edge data ED and texture information TI. An example of the bleeding imparting process will be described later.

[0027] The texture imparting unit 140 applies a process for imparting the texture of the printing medium to the bleed-added proof image data ZPF obtained by the bleed-adding process using the texture information TI, thereby creating texture-imparted proof image data TPF that simulates the texture. The texture imparting process may be similar to the process disclosed in Japanese Patent Application Laid-Open No. 06-86045. Specifically, the difference between the average texture value and each texture value may be multiplied by a gain and the result may be added to the pixel value of the bleed-added proof image data ZPF. Texture imparting may also be performed according to other known methods. If the bleed-added proof image data ZPF is expressed in the CIE-L*a*b* color system, the texture imparting process may be performed only on the lightness L*. If the bleed-added proof image data ZPF is expressed in the RGB color system, the texture imparting process may be performed on each RGB color component.

[0028] FIG. 5 is an explanatory diagram showing an example of texture information TI. As texture information TI, a height map used in 3D rendering or a brightness value map generated based on image data obtained by photographing a print medium can be used. In either case, the texture information TI is preferably configured as a map of texture values ​​that indicate the unevenness of the print medium. In the example of FIG. 5, the texture value assigned to each pixel is brightness L*. Pixels with high brightness L* correspond to convex portions, and pixels with low brightness L* correspond to concave portions. However, values ​​in the range of 0 (dark) to 100 (light) may also be used as the texture value. The image area of ​​the texture information TI preferably has a size that encompasses the basic proof image.

[0029] 6 is an explanatory diagram showing an example of a bleeding parameter setting screen ZW. This bleeding parameter setting screen ZW has a selection tool ZT1 for "A. Bleeding mode," setting tools ZT2 and ZT3 for "B. Bleeding characteristic value," a setting tool ZT4 for "C. Filter size for processing targeting all pixels for bleeding," and setting tools ZT11 to ZT14 for "D. Bleeding setting for text."

[0030] The "A. Bleeding Mode" selection tool ZT1 is configured to allow selection of one of multiple bleed modes M1 to M6. Each bleed mode option has a texture-dependent designation parameter TDP and a bleed target parameter ZSP.

[0031] The texture-dependent parameter TDP is a parameter that specifies whether or not texture dependence is present. In this embodiment, the texture-dependent parameter TDP has one of three values: "texture dependence: none," "texture dependence: yes (bright direction)," and "texture dependence: yes (dark direction)." "Texture dependence: none" means that the blurring process is performed without relying on the texture information TI. "Texture dependence: yes (bright direction)" means that blurring is applied to a blurring target candidate pixel adjacent to an edge pixel when the lightness L* of the texture value of the blurring target candidate pixel adjacent to an edge pixel is greater than a preset threshold. "Texture dependence: yes (dark direction)" means that blurring is applied to a blurring target candidate pixel adjacent to an edge pixel when the lightness L* of the texture value of the blurring target candidate pixel is equal to or less than a threshold. The bright direction is also referred to as the "increase direction," and the dark direction is also referred to as the "decrease direction."

[0032] When the texture information TI represents the brightness of the printing medium, bleeding tends to occur more easily in pixels with high brightness, so dependency in the "brighter direction (increasing direction)" is usually used as the texture dependency. When the texture information TI is a height map, bleeding also tends to occur more easily in pixels with high height, so dependency in the "brighter direction (increasing direction)" is usually used as the texture dependency. However, there are cases where the "darker direction (decreasing direction)" is preferable as the texture dependency.

[0033] Texture dependency is "bright" when, for example, ink bleeds along the threads of the weave of the fabric, which is the printing medium. In the texture information TI, the convex parts of the weave have high brightness. For example, in the case of a fabric with a loose weave, the positions of the threads are bright pixels, and ink bleed occurs along the threads, resulting in texture dependency being "bright." On the other hand, texture dependency is "dark" when, for example, ink bleeds along the grooves of the weave of the fabric, which is the printing medium. In other words, if the ink is absorbed into the grooves faster than it is absorbed into the threads, there is a possibility that the ink will bleed in the dark direction.

[0034] Whether the texture dependency is "light direction" or "dark direction" depends on the type of print medium and the type of ink. The type of print medium is determined by factors such as the yarn material, knitting method, and pre-treatment. Pre-treatment is a process in which a chemical is applied and dried before printing to ensure that the ink adheres to the fabric. In practice, it is preferable for the user to check the bleeding pattern when actually printing and select either "light direction" or "dark direction."

[0035] "Texture Dependent: Yes (Lighter)" and "Texture Dependent: Yes (Darker)" are parameters that indicate whether bleeding is applied depending on whether the relationship between the texture value and the threshold is a first relationship or a second relationship. For example, the first relationship is a relationship in which the texture value is greater than the threshold, and the second relationship is a relationship in which the texture value is less than or equal to the threshold. "Texture Dependent: Yes (Lighter)" and "Texture Dependent: Yes (Darker)" are also referred to as "bleeding direction parameters."

[0036] The bleeding target parameter ZSP is a parameter that specifies whether the bleeding target is "all pixels" or "bleed range." If the bleeding target is "all pixels," bleeding is applied to all pixels of the basic proof image represented by the basic proof image data BPF. If the bleeding target is "bleed range," pixels that are adjacent to edge pixels and exist in the "bleed range" become candidate bleeding target pixels.

[0037] Below the multiple blur modes M1 to M6, a selection tool SMT for selecting the reference position of the texture information is provided. Here, two options for the reference position of the texture information are provided: "blur-target candidate pixel only" and "blur-target candidate pixel + edge pixel." When the reference position of the texture information is "blur-target candidate pixel only," only the texture values ​​of the blur-target candidate pixel are referenced to determine whether or not to impart blur to the blur-target candidate pixel. As described above, the blur-target candidate pixel is a pixel adjacent to an edge pixel and located in the "blur range." When the reference position of the texture information is "blur-target candidate pixel + edge pixel," the texture values ​​of both the blur-target candidate pixel and the edge pixel are referenced to determine whether or not to impart blur to the blur-target candidate pixel. Specific examples of these options will be described later.

[0038] The "B. Bleeding Characteristic Value" setting tools include a "Bleeding Range" setting tool ZT2 and a "Bleeding Intensity Coefficient" setting tool ZT3. In the example of FIG. 6, the "Bleeding Range" is set to 1 pixel, and the "Bleeding Intensity Coefficient" is set to 1.0. The "Bleeding Range" can be set to any number of pixels greater than or equal to 1. However, instead of specifying the "Bleeding Range" by pixel count, options such as "Small, Medium, Large" may be displayed, and the number of pixels may be calculated based on the option and the resolution of the proof image. Furthermore, instead of specifying the "Bleeding Range" by pixel value, a specified difference value of color difference ΔE, brightness difference, or saturation difference may be specified as the difference pixel value between edge pixels and white pixels in the basic proof image data BPF. In this case, pixels adjacent to the edge pixels whose difference pixel value is equal to or less than the specified value are subject to bleed application.

[0039] When the bleeding target is "all pixels," the bleeding process that targets all pixels of the proof image is performed using a blur filter. The size of the blur filter is set using the setting tool ZT4 for "C. Filter size for processing that targets all pixels for bleeding." In the example in Figure 6, the filter size is set to "small."

[0040] The setting tools for "D. Bleeding Settings for Characters" include a setting tool ZT11 for specifying whether or not to perform a bleed processing on characters, a setting tool ZT12 for setting the bleed direction, a setting tool ZT13 for setting the bleed range, and a setting tool ZT14 for setting the bleed strength coefficient. However, a simple setting tool for selecting options such as "weak bleed" or "no bleed" may also be used. In this case, it is preferable that detailed setting values ​​corresponding to each option are set in advance.

[0041] The blurring process for text is a process in which, when the basic proof image data BPF includes character data representing characters, pixels constituting the outline of the characters are extracted as edge pixels and blurred. The user may specify the edge pixels of the characters using a GUI (Graphical User Interface). Alternatively, edge pixels may be extracted using a detection tool that automatically detects characters in an image. When blurring process for text is specified, the settings in the setting tools ZT1 to ZT4 are not applied to the text, and the blurring process is performed according to the settings in the setting tools ZT11 to ZT14 in "D. Bluring Settings for Text." In this way, by performing the blurring process for text according to settings that differ from those for other image portions, it is possible to impart a blur appropriate to the text.

[0042] Below, examples of blurring processes using multiple blur modes M1 to M6 will be explained in order. In the following explanation, it is assumed that the multiple blur modes M1 to M6 have "blurring target candidate pixels only" selected as the initial setting for the reference position of the texture information. When "blurring target candidate pixels + edge pixels" is selected as the reference position of the texture information, it will be explained as a supplementary mode for one of the blur modes.

[0043] FIG. 7 is an explanatory diagram showing an example of the bleeding process using bleeding mode M1. The bleeding mode M1 is a mode with "texture dependency: none" and "bleed target: all pixels." In this example, the filter size is set to "small." A 3x3 pixel Gaussian filter is used as the blurring filter BF. Note that other blurring filters, such as an averaging filter, may be used instead of the Gaussian filter. A blurring filter is also called a "smoothing filter." In the bleeding process using bleeding mode M1, the blurring filter BF is applied sequentially to all pixels of the basic proof image to create the bleeding-added proof image data ZPF. As a result, pixels adjacent to the edge pixels of the dark-color ink ejection area IP become bleeding-added pixels.

[0044] FIG. 8 is an explanatory diagram showing an example of a bleed application process using bleed mode M2. The bleed mode M2 ​​is a mode with "Texture Dependency: Yes (Bright Direction)" and "Bleed Target: Bleed Range." In this example, the settings are "Bleed Range = 1 Pixel" and "Texture Information Reference Position: Only bleed target candidate pixel." The bleed target candidate pixel Z is a pixel adjacent to an edge pixel in the basic proof image and within a range of one pixel from the edge pixel. Because "Texture Dependency: Yes (Bright Direction)" is selected, pixels in the texture information TI whose texture values ​​exceed the threshold are hatched as bleed application candidates. In the example shown in FIG. 8, the threshold value is 90, which is the average value of the texture values ​​in the texture information TI. The reason for using the average value is that the range and distribution of texture values ​​in the texture information TI vary significantly depending on the printing medium, making the average value an appropriate threshold for determining the magnitude of the texture value. However, the user can set any threshold value, and it is preferable to set an appropriate threshold value based on the average texture value. In the blurring process, blurring is applied to pixels whose texture values ​​exceed a threshold value among the blurring candidate pixels Z. In the blurring proof image data ZPF, the blurring application pixels to which blurring has been applied are hatched.

[0045] The pixel value Lz after the blurring is added is determined, for example, according to the following formula. Lz = Le + (L*_white - Le) × (1.0 - α) = α×Le + (1.0 - α)×L*_white (q1) Here, Le is the basic proof pixel value of the edge pixel, L*_white is the basic proof pixel value of the background BG, and α is the bleeding intensity coefficient. The bleeding intensity coefficient α is a value greater than 0 and equal to or less than 1, and is set using the setting tool ZT3 in FIG. 6.

[0046] When the pixel value is lightness, the larger the blur strength coefficient α, the greater the degree of blur. In this embodiment, the basic proof pixel value is expressed as lightness, and the blur strength coefficient α is set to 1 or less. When the blur strength coefficient α is equal to 1.0, the pixel value Lz after blurring is added is a direct copy of the pixel value Le of the edge pixel. When the blur strength coefficient α is less than 1.0, the smaller the blur strength coefficient α, the closer the pixel value Lz after blurring is added to the pixel value L*_white of the background BG.

[0047] The pixel value Lz after the blurring is added may be determined according to the following formula instead of the above formula (q1). Lz = Le + (L0 - Le) × (1.0 - α) = α×Le + (1.0 - α)×L0 (q2) Here, L0 is the basic proof pixel value of the bleeding-added pixel before the bleeding-adding process. When this formula (q2) is used, if the bleeding strength coefficient α is less than 1.0, the pixel value Lz after the bleeding addition approaches the pixel value L0 before the bleeding addition as the bleeding strength coefficient α becomes smaller.

[0048] When the blurring range is two or more pixels, it is preferable to decrease the coefficient α linearly or curvedly with increasing distance from the edge pixel so that the blurring intensity decreases with increasing distance from the edge pixel.

[0049] If the basic proof image data BPF is expressed in the CIE-L*a*b* color system, the bleeding process may be performed not only on the lightness L* but also on the a* and b* values ​​according to the above formula (q1) or (q2). However, for the a* and b* values, it is preferable to copy the a* and b* values ​​of the edge pixels directly to the bleeding-to-be-given pixels. This makes it possible to reflect the color of the edge pixels in the bleeding-to-be-given pixels. Even if the basic proof image data BPF is expressed in another color system, the bleeding process may be performed on the pixel values ​​of that color system according to the above formula (q1) or (q2).

[0050] FIG. 9 is an explanatory diagram showing another example of the blurring process using the blurring mode M2. The example in FIG. 9 differs from the example in FIG. 8 only in that the "blurring range = 2 pixels" setting is used. In this case, the blurring target candidate pixel Z is a pixel adjacent to an edge pixel in the basic proof image and within a range of two pixels from the edge pixel. In the blurring process, blurring is applied to pixels among the blurring target candidate pixel Z whose texture value exceeds a threshold. However, pixel NZP is a blurring target candidate pixel Z and corresponds to a pixel whose texture value exceeds the threshold, but is excluded from the blurring application pixels. This is because the texture value of the pixel between pixel NZP and the edge pixel is equal to or less than the threshold. In this way, it is preferable that the blurring application pixels be selected so that they are continuous toward the outer periphery of the edge pixel.

[0051] FIG. 10 is an explanatory diagram showing an example of a blurring process using the blurring mode M2a. The blurring mode M2a is a type of the blurring mode M2 ​​and is a supplementary mode that is set as "reference position of texture information: blurring target candidate pixel + edge pixel." FIG. 10 differs from the example of FIG. 8 only in the setting of the reference position of texture information. In this case, the blurring process applies blur to pixels whose texture value of the blurring target candidate pixel Z exceeds a threshold and whose texture value of the edge pixel also exceeds a threshold. For pixel NZP, the texture value of the blurring target candidate pixel Z exceeds the threshold, but the texture value of the edge pixel is equal to or less than the threshold, so it is excluded from the blurring application pixels.

[0052] FIG. 11 is an explanatory diagram showing an example of a bleeding process using bleeding mode M3. The bleeding mode M3 is a mode with "texture dependency: yes (dark direction)" and "bleed target: bleeding range." In this example, "bleed range = 1 pixel" and "texture information reference position: only bleeding target candidate pixels" are set. Because "texture dependency: yes (dark direction)" is set, pixels in the texture information TI whose texture value is equal to or less than the threshold are hatched as bleeding target candidates. In the bleeding process, bleeding is applied to pixels among the bleeding target candidate pixels Z whose texture value is equal to or less than the threshold. In bleeding mode M3 as well, the pixel value after bleeding is applied is calculated according to the above formula (q1) or (q2).

[0053] FIG. 12 is an explanatory diagram showing an example of the bleeding process in the bleeding mode M4. The bleeding mode M4 is a mode with "texture dependency: none" and "bleeding target: bleeding range." In this example, "bleeding range = 1 pixel" is set. The bleeding target candidate pixel Z is a pixel that is adjacent to an edge pixel of the basic proof image and is within a range of one pixel from the edge pixel. In the bleeding process in the bleeding mode M4, bleeding is applied to all the bleeding target candidate pixels Z. In the bleeding mode M4 as well, the pixel value after the bleeding is applied is calculated according to the above formula (q1) or (q2).

[0054] The above-mentioned bleeding modes M1 and M4 are texture-independent modes that do not depend on texture information, while the bleeding modes M2 and M3 are texture-dependent modes that depend on texture information.

[0055] As can be seen from FIG. 6, the bleeding mode M5 is a mode in which bleeding processing is performed in the bleeding mode M1 after the bleeding processing in the bleeding mode M2. The bleeding mode M6 is a mode in which bleeding processing is performed in the bleeding mode M3 after the bleeding processing in the bleeding mode M1. Each of these modes M5 and M6 is also called a "composite bleeding mode." Note that some of the multiple bleeding modes M1 to M6 shown in FIG. 6 may be omitted. Furthermore, other bleeding modes may be added.

[0056] 13 is a flowchart showing the steps of the proof image data creation process. In step S10, the basic proof image acquisition unit 120 acquires basic proof image data BPF. In step S20, the texture addition unit 140 acquires texture information TI. As described above, the texture information TI is also used by the bleed addition unit 132. In step S30, the bleed processing unit 130 acquires bleed parameters ZP. In step S40, the edge extraction unit 131 extracts edges of the basic proof image. In step S50, the bleed addition unit 132 executes bleed addition processing.

[0057] FIG. 14 is a flowchart showing the detailed procedure of the blurring process in step S50. In step S51, it is determined whether the blurring is texture-dependent. If it is texture-independent, the process proceeds to step S52, where it is determined whether the blurring target is all pixels or the blurring range. If it is texture-dependent, the process proceeds to step S53, where it is determined whether the blurring direction is the light direction or the dark direction. As a result, one of the blurring modes M1 to M4 is selected and executed in steps S54 to S57. Note that in the case of the composite blurring mode M5 shown in FIG. 6, the blurring mode M2 ​​is executed in step S56, and after it is determined in step S58 that the process is not complete and the process returns to step S51, the blurring mode M1 is executed in step S54. Similarly, in the case of the composite blurring mode M6, the blurring mode M3 is executed in step S57, and after it is determined in step S58 that the process is not complete and the process returns to step S51, the blurring mode M1 is executed in step S54.

[0058] When the bleeding process is completed in this manner, the texture applying unit 140 executes the texture applying process in step S60 of Fig. 13. The order of the steps in Fig. 13 and Fig. 14 may be changed as appropriate.

[0059] In the above embodiment, the bleeding parameter ZP is used to apply a bleeding process to the basic proof image data BPF, thereby obtaining bleeding-added proof image data ZPF that simulates the bleeding state. Also, the texture information TI is used to apply a texture-added process to the bleeding proof image data ZPF, thereby obtaining texture-added proof image data TPF that simulates the bleeding state and texture.

[0060] Other forms: The present disclosure is not limited to the above-described embodiments and can be realized in various forms without departing from the spirit thereof. For example, the present disclosure can also be realized in the following forms. The technical features in the above embodiments corresponding to the technical features in each form described below can be appropriately replaced or combined to solve some or all of the problems of the present disclosure or to achieve some or all of the effects of the present disclosure. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted.

[0061] (1) According to a first aspect of the present disclosure, there is provided a method for creating proof image data, the method including: (a) acquiring basic proof image data for reproducing, with a proof output device, the colors of a printed matter printed on a printing medium using a printing press; and (b) applying a bleeding process to the basic proof image data using bleeding parameters representing the bleeding state of ink in the printed matter, thereby creating bleeding-added proof image data that simulates the bleeding state. According to this method, proof image data that simulates the bleeding state can be obtained.

[0062] (2) The above method may further include (c) a step of creating textured proof image data that simulates the texture by applying a texture imparting process to the bleed proof image data using texture information that represents the texture of the printing medium. According to this method, it is possible to obtain textured proof image data that simulates the bleeding state and texture.

[0063] (3) In the above method, the bleeding parameters may include a bleeding range parameter that defines a bleeding range, and step (b) may include (b1) a step of extracting an edge of the basic proof image represented by the basic proof image data, and (b2) a step of applying bleeding to pixel values ​​of the basic proof image data in a bleeding target area adjacent to the edge and spanning the bleeding range. According to this method, the area to which bleeding is applied can be changed by adjusting the bleeding range parameter.

[0064] (4) In the above method, the bleeding process may include a texture-dependent mode that depends on the texture information, the texture information including a texture value for each pixel, and the bleeding parameters for the texture-dependent mode may include a bleeding direction parameter that indicates whether to apply bleeding depending on whether a magnitude relationship between the texture value and a threshold is a first magnitude relationship or a second magnitude relationship. In the texture-dependent mode, step (b2) may be executed to apply bleeding to pixel values ​​of the basic proof image data for pixels in the bleeding target area that are determined to be applied with bleeding according to the bleeding direction parameter. According to this method, the pixels to which bleeding is applied can be changed by adjusting the bleeding direction parameter.

[0065] (5) In the above method, the blurring process may further include a texture-independent mode in which blurring is applied to all pixels regardless of the texture information, and when the blurring parameters include a first parameter related to the texture-dependent mode and a second parameter related to the texture-independent mode, step (b) may include performing steps (b1) and (b2) according to the first parameter, and then applying a blur filter process to all pixels according to the second parameter. This method makes it possible to impart bleeding over the entire proof image in addition to bleeding near the edges.

[0066] (6) In the above method, the blurring process may include a mode in which blurring is applied to all pixels, and step (b) may include a step of applying a blur filter process to all pixels of the basic proof image represented by the basic proof image data. This method makes it possible to impart bleeding across the entire proof image.

[0067] (7) According to a second aspect of the present disclosure, there is provided a proof image data creation device including: a basic proof image acquisition unit that acquires basic proof image data for reproducing, by a proof output device, the colors of a printed matter printed on a printing medium using a printing press; and a bleed processing unit that applies a bleed addition process to the basic proof image data using bleed parameters that represent the bleed state of ink in the printed matter, thereby creating bleed-added proof image data that simulates the bleed state.

[0068] (8) According to a third aspect of the present disclosure, there is provided a computer program for creating proof image data, which causes a computer to execute (a) a process for acquiring basic proof image data for reproducing, by a proof output device, the colors of a printed matter printed on a printing medium using a printing press, and (b) a process for creating bleeding-added proof image data that simulates the bleeding state by applying a bleeding addition process to the basic proof image data using bleeding parameters that represent the bleeding state of ink in the printed matter.

[0069] The present disclosure may be realized in various forms other than those described above, such as a computer program that realizes the functions of a proof image data creation device, or a non-transitory storage medium on which a computer program is recorded. [Explanation of symbols]

[0070] 50...CPU, 60...storage unit, 61...proof image creation program, 70...input / output interface, 100...proof image data creation device, 120...basic proof image acquisition unit, 130...bleed processing unit, 131...edge extraction unit, 132...bleed application unit, 140...texture application unit, 150...display device, 200...proof printing device, 300...printing machine, 500...printing system

Claims

1. 1. A method for creating proof image data, comprising: (a) acquiring basic proof image data for reproducing the colors of a printed matter printed on a printing medium using a printing press with a proof output device; (b) applying a bleeding process to the basic proof image data using bleeding parameters that represent the bleeding state of ink in the printed matter, thereby creating bleeding-added proof image data that simulates the bleeding state; A method comprising:

2. 10. The method of claim 1 further comprising: (c) applying a texture imparting process to the bleed proof image data using texture information representing the texture of the printing medium, thereby creating texture imparted proof image data that simulates the texture.

3. 3. The method of claim 2, the bleeding parameters include a bleeding range parameter that defines a bleeding range, The step (b) (b1) extracting edges of a basic proof image represented by the basic proof image data; (b2) applying bleeding to pixel values ​​of the basic proof image data in a bleeding target area adjacent to the edge and spanning the bleeding range; A method comprising:

4. 4. The method of claim 3, the bleeding process includes a texture-dependent mode that depends on the texture information, the texture information includes a texture value for each pixel; the bleeding parameter for the texture-dependent mode includes a bleeding direction parameter indicating whether to impart bleeding depending on whether a magnitude relationship between the texture value and a threshold is a first magnitude relationship or a second magnitude relationship, In the texture-dependent mode, step (b2) is executed to impart the bleeding to pixel values ​​of the basic proof image data for pixels in the bleeding target area that are determined to be subjected to the bleeding according to the bleeding direction parameter.

5. 5. The method of claim 4, the blurring process further includes a texture-independent mode in which blurring is applied to all pixels without depending on the texture information, When the bleeding parameters include a first parameter for the texture-dependent mode and a second parameter for the texture-independent mode, The method of claim 1, wherein the step (b) applies blurring filtering to all the pixels according to the second parameter after performing the steps (b1) and (b2) according to the first parameter.

6. 10. The method of claim 1, the blurring process includes a mode in which blurring is applied to all pixels; The method, wherein step (b) includes applying a blur filter to all pixels of the base proof image represented by the base proof image data.

7. A proof image data creation device, a basic proof image acquisition unit that acquires basic proof image data for reproducing the colors of a print that is printed on a printing medium using a printing press with a proof output device; a bleeding processing unit that applies bleeding processing to the basic proof image data using bleeding parameters that represent the bleeding state of ink in the printed matter, thereby creating bleeding-added proof image data that simulates the bleeding state; A proof image data creation device comprising:

8. A computer program for creating proof image data, (a) a process of acquiring basic proof image data for reproducing the colors of a printed matter printed on a printing medium using a printing press with a proof output device; (b) applying a bleeding process to the basic proof image data using bleeding parameters that represent the bleeding state of ink in the printed matter, thereby creating bleeding-added proof image data that simulates the bleeding state; A computer program that causes a computer to execute the following.

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