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 determining ink amount image data representing the amount of ink in each pixel when printing a print on a print medium by using a printer according to input image data; (b) a step of determining a bleeding parameter of each pixel according to the amount of ink in each pixel; (c) a step of applying bleeding adding processing to any one of the input image data and image data for actual printing obtained by converting the color space of the input image data into an output color space for the printer, according to the bleeding parameter, to generate bleeding added image data; and (d) a step of executing processing of converting the color space of the bleeding added image data into an output color space for a proof output device to generate bleeding added proof image data.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, the size of each halftone dot in the proof is made the same as the size of each halftone dot in the printed matter, and the color tone is made similar to the printed matter to the extent that the difference from the printed matter is not recognized, thereby creating a highly reliable proof image. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-30277 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) determining ink volume image data representing an amount of ink for each pixel when a printed matter is printed on a print medium using a printing press according to input image data; (b) determining a bleeding parameter for each pixel according to the ink volume for each pixel; (c) creating bleeding-added image data by applying a bleeding-adding process to either the input image data or image data for actual printing obtained by converting the color space of the input image data into an output color space for the printing press according to the bleeding parameters; and (d) creating bleeding-added proof image data by performing a process of converting the color space of the bleeding-added image data into an output color space for a proof output device.

[0006] According to a second aspect of the present disclosure, there is provided a proof image data creation device, comprising: an ink amount calculation unit that calculates ink amount image data representing an ink amount for each pixel when a printed material is printed on a printing medium using a printing press according to input image data; a bleeding parameter determination unit that determines bleeding parameters for each pixel according to the ink amount for each pixel; a bleeding addition unit that creates bleeding-added image data by applying a bleeding addition process to either the input image data or image data for actual printing obtained by converting the color space of the input image data into an output color space for the printing press according to the bleeding parameters; and a color conversion unit that creates bleeding-added proof image data by performing a process of converting the color space of the bleeding-added image data into an output color space for a proof output device.

[0007] According to a third aspect of the present disclosure, there is provided a computer program for creating proof image data. The computer program causes a computer to execute the following steps: (a) determining ink volume image data representing the amount of ink for each pixel when printing a printed material on a printing medium using a printing press according to input image data; (b) determining a bleeding parameter for each pixel according to the ink volume for each pixel; (c) creating bleeding-added image data by applying a bleeding-adding process to either the input image data or image data for actual printing obtained by converting the color space of the input image data into an output color space for the printing press according to the bleeding parameters; and (d) creating bleeding-added proof image data by converting the color space of the bleeding-added image data into an output color space for a proof output device. [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 an input image. [Figure 5] FIG. 4 is an explanatory diagram showing an example of a bleeding process according to the first embodiment. [Figure 6] FIG. 3 is an explanatory diagram showing a blurring filter used in the first embodiment. [Figure 7] FIG. 10 is an explanatory diagram showing another example of the bleeding processing in the first embodiment. [Figure 8] 10 is a flowchart showing the procedure of a proof image creation process. [Figure 9] FIG. 10 is an explanatory diagram showing an example of a bleeding process according to the second embodiment. [Figure 10] FIG. 10 is an explanatory diagram showing a blurring filter used in the second embodiment. [Figure 11] FIG. 11 is an explanatory diagram showing a method for adjusting a blurring filter in the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] A. First embodiment: FIG. 1 is an explanatory diagram showing a printing system 500 for proofreading printed materials. This printing system 500 includes a printing press 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 110 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 110 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 110 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 an ink amount calculation unit 120, a bleeding parameter determination unit 130, a bleeding addition unit 140, a color conversion unit 150, and a texture addition unit 160. At least some of the functions of these units 120 to 160 may be realized by hardware circuits or on the cloud.

[0014] The input / output interface 70 is connected to a display device 110 and a proof printing device 200. The display device 110 is used to display windows and proof images as a user interface.

[0015] 3 is an explanatory diagram showing the flow of the proof image creation process. The ink amount calculation unit 120 creates ink amount image data QIM by calculating the ink amount for each pixel during actual printing based on the input image data IM.

[0016] FIG. 4 is an explanatory diagram showing an example of an input image represented by input image data IM. The input image is an image in which an ink ejection area IP including a dark blue portion and a light blue portion is placed against a background BG. The input image data IM is expressed in an input color space. As the input color space, an RGB color space such as the sRGB color space or the AdobeRGB color space, or a CMYK color space such as Japan Color 2011 can be used. In the example of FIG. 3, the input color space of the input image data IM is the RGB color space.

[0017] The amount of ink for each pixel can be determined by sequentially executing the following three stages of conversion processing on the input image data IM. <First Conversion Process> The input color space is converted to a device-independent color space using the first ICC profile CP1. <Second Conversion Process> The second ICC profile CP2 is used to convert from the device-independent color space to the output color space of the printing machine 300. <Third Conversion Process> The ink amount conversion lookup table CT is used to convert from the output color space of the printing machine 300 to the ink amount space.

[0018] These three-stage conversion processes are the same as those executed when printing a printed material PM using the printing press 300. However, instead of the three-stage conversion processes described above, the input color space of the input image data IM may be converted into the ink amount space in a single stage of conversion process using a single lookup table or a single ICC profile created in advance.

[0019] The bleeding parameter determination unit 130 determines the bleeding parameter ZP for each pixel according to the ink amount for each pixel in the ink amount image data QIM. The bleeding parameter ZP is a parameter related to bleeding in the printed material PM printed by the printing press 300. In this embodiment, the bleeding parameter ZP includes the filter type of the blurring filter used in the bleeding application process. Specific examples of blurring filters will be described later.

[0020] The bleeding addition unit 140 creates bleeding-added image data ZIM by applying bleeding addition processing in accordance with the bleeding parameter ZP. This bleeding addition processing is performed on either the input image data IM or the actual printing image data obtained by converting the input color space of the input image data IM into the output color space for the printing machine 300. Therefore, the bleeding-added image data ZIM is expressed in the input color space of the input image data IM or the output color space for the printing machine 300. A processing example of the bleeding addition processing will be described later.

[0021] When using the actual printing image data as the target image for the bleeding process, the bleeding addition unit 140 executes color conversion processing using ICC profiles CP1 and CP2 to convert the input color space of the input image data IM into the output color space for the printing press 300. This color conversion processing is the same as the two-stage conversion processing of the first conversion processing and the second conversion processing described above. If the ink amount calculation unit 120 executes the first conversion processing and the second conversion processing when creating the ink amount image data QIM, the actual printing image data resulting from these processing may be supplied to the bleeding addition unit 140 as the target image for the bleeding process.

[0022] The color conversion unit 150 applies color conversion processing to the bleeding-added image data ZIM using the second ICC profile CP2 and the third ICC profile CP3 to create bleeding-added proof image data ZPF. That is, the input color space is converted to the L*a*b* color space using the second ICC profile CP2, and the L*a*b* color space is converted to the CMYK color space using the third ICC profile CP3. This color conversion processing converts the color space of the bleeding-added image data ZIM into the output color space for the proof output device. In the example of FIG. 3, the output color space for the proof output device is the CMYK color space.

[0023] The texture imparting unit 160 applies a process to the bleed-proof image data ZPF to impart the texture of the printing medium 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 added to the pixel value of the bleed-proof image data ZPF. Texture imparting may also be performed using other known methods. If the bleed-proof image data ZPF is expressed in the CMYK color system, the texture imparting process may be performed for each CMYK color component. If the bleed-proof image data ZPF is expressed in the CIE-L*a*b* color system, the texture imparting process may be performed only for the lightness L*. Texture imparting may also be performed before color conversion by the color conversion unit 150.

[0024] 5 is an explanatory diagram showing an example of the bleeding process in the first embodiment. In the ink amount image data QIM calculated by the ink amount calculation unit 120, it is assumed that the ink amounts for pixels in the background BG are (C,M,Y,K)=(0,0,0,0), the ink amounts for pixels in the light blue part of the ink discharge area IP are (C,M,Y,K)=(64,0,0,0), and the ink amounts for pixels in the dark blue part are (C,M,Y,K)=(128,0,0,0).

[0025] The bleeding parameter determination unit 130 determines a bleeding parameter ZP1 for the printing medium according to the amount of ink for each pixel. The bleeding parameter ZP1 is data indicating the filter type of the blur filter BF appropriate for each pixel. In the example of FIG. 5, the filter types are 1, 3, and 5. These numbers indicate the filter size.

[0026] FIG. 6 is an explanatory diagram showing the blur filter BF used in the first embodiment. The filter type for each pixel is determined by referencing the filter type table FT1. The filter type table FT1 indicates the relationship between the total ink amount for each pixel and the filter type. "Total ink amount" refers to the total value of the ink amounts of multiple types of ink (C, M, Y, K). In the examples of FIGS. 4 and 5, the total ink amount for the background BG pixels is 0, the total ink amount for the light blue pixels is 64, and the total ink amount for the dark blue pixels is 128. In the first embodiment, the filter types used are values ​​1, 3, 5, and 7. These filter types indicate the filter size of the blur filter BF. Generally, the larger the filter size of the blur filter BF, the greater the blur effect. Therefore, the filter type can also be considered to indicate the blur effect of the blur filter BF.

[0027] The filter types in the filter type table FT1 are equivalent to the filter sizes calculated according to the following formula: Fs = ROUNDDOWN((Qsum / 64), 0)×2 + 1 (q1) Here, Fs is the filter size, ROUNDDOWN(number, number of digits) is a function that rounds down a number to the specified number of digits, and Qsum is the total amount of ink for each pixel.

[0028] FIG. 6 shows examples of a 1x1 pixel blur filter BF_1, a 3x3 pixel blur filter BF_3, a 5x5 pixel blur filter BF_5, and a 7x7 pixel blur filter BF_7. These blur filters BF are Gaussian filters. A blur filter BF with a filter size of 1x1 pixel does not change pixel values ​​before and after filtering, so it is equivalent to not applying a blur filter. Note that an averaging filter may also be used as the blur filter BF. A blur filter is also called a "smoothing filter."

[0029] Generally, a blur filter BF has the property that the larger the filter size, the greater the blur effect. The blur effect can be confirmed, for example, by comparing the pixel values ​​of adjacent pixels at the edge of an image before and after filter processing. In other words, the smaller the difference in pixel values ​​between adjacent pixels due to filter processing, the greater the blur effect. As can be seen from the contents of filter type table FT1, in this embodiment, the greater the total ink amount, the greater the blur effect used is a blur filter BF. The reason for this is that it is estimated that the greater the total ink amount, the greater the bleeding.

[0030] Instead of using the total ink amount, the filter type may be determined using the ink amount of a specific ink that is prone to bleeding. The filter type may also be determined using the liquid amounts of penetrant liquid and fixer, which are factors that cause bleeding. Since the penetrant liquid has a particularly large effect on bleeding, determining the filter type according to the liquid amount of the penetrant liquid is expected to effectively reflect the bleeding state. In this disclosure, the term "ink" is used to include penetrant liquid and fixer. When referring to ink that does not contain penetrant liquid or fixer, the term "process ink" is used.

[0031] Even with the same ink set, the tendency for individual inks to bleed may differ depending on the blending amounts of the ink components. Furthermore, the greater the amount of penetrant liquid, the greater the penetration effect, but the greater the tendency for the ink to bleed. Therefore, it is preferable to set in advance which ink amounts to use to determine the filter type depending on the ink set used in the printing machine 300.

[0032] Furthermore, the preferred values ​​of the filter size and filter coefficient of the blur filter differ depending on the printing press 300 and printing medium used for the actual printing. Therefore, it is preferable to set the preferred values ​​of the filter size and filter coefficient in advance according to the combination of the printing press 300 and printing medium.

[0033] The bleeding parameter ZP1 shown in FIG. 5 can be thought of as indicating the state in which the center of the blur filter BF of the filter type selected according to the ink amount of each pixel is temporarily positioned at each pixel.

[0034] The filter map FM1 shown in FIG. 5 is created by modifying the blur parameter ZP1 in the following steps. <Step 1> The center of the blur filter BF indicated by the blur parameter ZP1 is provisionally positioned at each pixel, and it is provisionally determined that the blur filter BF will be applied to all pixels included in the filter area of ​​the provisionally positioned blur filter BF. As a result, it is provisionally determined that one or more blur filters BF will be applied to each pixel. <Step 2> Of the one or more blur filters BF tentatively determined to be applied to each pixel in step 1, it is determined that the blur filter BF with the greatest blurring effect is to be applied to that pixel.

[0035] The blur-added image data ZIM is created by applying a filter process using the blur filter BF indicated by the filter map FM1 to the target image for the blur-adding process. This filter process calculates a weighted average of pixel values ​​using the filter coefficients of the blur filter BF as weights. As mentioned above, the target image for the blur-adding process can be either the input image data IM or the actual printing image data, which is obtained by converting the input color space of the input image data IM into the output color space for the printer 300.

[0036] It is preferable that the filtering process using the blurring filter BF be performed on each color component of the image to be processed. For example, if the image to be subjected to the blurring process is image data for actual printing, the filtering process is performed on each color component of CMYK, which is the output color space of the printing machine 300.

[0037] Of the multiple color components of the image to be processed, filter processing may be performed on only certain color components. For example, if yellow ink is particularly prone to bleeding, filter processing may be performed on only the Y component. In this case, some inks that cause bleeding are selected, and the bleeding parameter ZP is determined according to the ink volume of the selected ink. For example, penetrant liquid may be selected as the ink that causes bleeding, and the bleeding parameter ZP may be determined according to the volume of the penetrant liquid.

[0038] In the example of Figure 5, pixels to which bleeding has been substantially imparted in the bleeding-imparted image data ZIM are indicated by hatching. As can be seen from this example, the bleeding-imparted image data ZIM simulates a state in which the greater the amount of ink, the greater the spreading of bleeding around the pixel.

[0039] FIG. 7 is an explanatory diagram showing another example of blurring processing in the first embodiment. The only difference from FIG. 5 is the filter coefficients of the 3×3 pixel blurring filter; the rest is the same as FIG. 5. The blurring filter BF_3a used in FIG. 7 has an apparent filter size of 5×5 pixels, but because the filter coefficients of the outermost pixels are all zero, the effective filter size is 3×3 pixels. Therefore, when creating the filter map FM1 from the blurring parameter ZP1, the filter size of the blurring filter BF_3a is processed as being 3×3 pixels. Even when using such a blurring filter BF_3a, it is possible to obtain an effect equivalent to that of the example in FIG. 5.

[0040] FIG. 8 is a flowchart showing the steps of the proof image creation process. In step S10, the ink amount calculation unit 120 acquires input image data IM. If the input image data IM is stored in the storage unit 60, the ink amount calculation unit 120 reads the input image data IM from the storage unit 60. In step S20, the ink amount calculation unit 120 generates ink amount image data QIM by calculating the ink amount for each pixel during actual printing based on the input image data IM. In step S30, the bleed parameter determination unit 130 determines a bleed parameter ZP for each pixel based on the ink amount for each pixel. In step S40, the bleed addition unit 140 applies a bleed addition process based on the bleed parameter ZP to generate bleed-added image data ZIM. This bleed addition process is performed on either the input image data IM or image data for actual printing, which is obtained by converting the input color space of the input image data IM into the output color space for the printing machine 300. In step S50, the color conversion unit 150 applies color conversion processing to the bleed-added image data ZIM using ICC profile CP3 to create bleed-added proof image data ZPF. In step S60, the texture addition unit 160 applies processing to the bleed-added proof image data ZPF to add the texture of the printing medium using texture information TI, thereby creating texture-added proof image data TPF that simulates the texture. Note that the order of steps S50 and S60 may be reversed. Also, step S60 may be omitted.

[0041] In the first embodiment, the bleeding parameter ZP for each pixel is determined according to the amount of ink in each pixel, bleeding processing is applied according to the bleeding parameter ZP to create bleeding-added image data ZIM, and processing is performed to convert the color space of the bleeding-added image data ZIM to the output color space for the proof output device, thereby obtaining bleeding-added proof image data ZPF that simulates the bleeding state.

[0042] B. Second embodiment: 9 is an explanatory diagram showing an example of the bleeding process in the second embodiment. The device configuration and processing procedure of the second embodiment are the same as those of the first embodiment. The second embodiment differs from the first embodiment mainly as follows. (1) Blur filters BF_a to BF_d are used. (2) The blur parameter ZP2 and the filter map MP2 are maps relating to filter types a to d.

[0043] 10 is an explanatory diagram showing the blurring filter BF used in the second embodiment. In the first embodiment described above, the filter type indicated the filter size, but in the second embodiment, the filter size is fixed, and the blurring effect is changed by changing the filter coefficient according to the filter type.

[0044] In FIG. 10, four filter types of blurring filters BF_a to BF_d are used. The third blurring filter BF_c is the same as the blurring filter BF_5 shown in FIG. 6. The filter magnifications registered in the filter type table FT2 indicate the filter coefficients of each blurring filter BF other than the center, relative to the filter coefficient of the third blurring filter BF_c. For example, the filter magnification of the first blurring filter BF_a is 1 / 16, so the filter coefficients of the other filters are 1 / 16 of the filter coefficient of the third blurring filter BF_c. However, decimals are rounded up or down. The blurring filters BF_a to BF_d of the second embodiment are the same as the blurring filter BF of the first embodiment in that the greater the ink amount, the greater the blurring effect.

[0045] Instead of determining the filter magnification using the filter type table FT2 shown in FIG. 10, the filter magnification may be calculated using the following formula. Fm = Qsum / 128 (q2) Here, Fm is the filter magnification, and Qsum is the total ink amount for each pixel. This filter magnification Fm is multiplied by the filter coefficients other than the center of the reference blur filter BF_c.

[0046] The content of the blur parameter ZP2 is the same as that of the blur parameter ZP1 shown in Fig. 5, where the numerical values ​​1, 3, and 5 are replaced with the letters a, b, and c. However, the filter map FM2 has more pixels marked with the letter b than the filter map FM1 shown in Fig. 5, where the numerical values ​​1, 3, and 5 are replaced with the letters a, b, and c. The reason for this is that the blur filter BF_b has a filter size of 5 x 5 pixels, which is larger than the filter size of the blur filter BF_3 used in the first embodiment. Therefore, when steps 1 and 2 described in the first embodiment are applied using the blur parameter ZP2, more pixels are applied to the blur filter BF_b.

[0047] The second embodiment also provides substantially the same effects as the first embodiment, and the various modifications and alterations described in the first embodiment can also be applied to the second embodiment.

[0048] C. Third embodiment: 11 is an explanatory diagram showing a method for adjusting the blur filter BF in the third embodiment. The device configuration and processing procedure of the third embodiment are the same as those of the first embodiment. The third embodiment differs from the first embodiment in the filter coefficients of the blur filter BF that are applied to each pixel according to the filter map FM1. That is, in the third embodiment, the filter coefficients of the blur filter BF that are applied to each pixel are changed according to the pixel values ​​of the surrounding pixels that exist around that pixel.

[0049] In Case 1 shown in Figure 11, blur filter BF_5a is used, which is a modification of the standard, original blur filter BF_5. The processing target pixel positioned at the center of blur filter BF_5a in Case 1 is a dark blue pixel, and its total ink amount is 128. Furthermore, when the center of the original blur filter BF_5 is positioned at the processing target pixel, blur filter BF_5a corresponds to a filter coefficient that is modified to be smaller for pixels within the filter area of ​​blur filter BF_5 that have less ink than the processing target pixel. In other words, the filter coefficient for pixels with less ink than the processing target pixel is modified to be smaller than the filter coefficient when the ink amount is equal to or greater than that of the processing target pixel. In the example of Case 1 in Figure 11, the modified filter coefficient is zero, but it may also be modified to a value greater than zero.

[0050] In Case 2, blur filter BF_5b is used, which is a modification of the original blur filter BF_5. The processing target pixel positioned at the center of blur filter BF_5b in Case 2 is a light blue pixel, and its total ink amount is 64. Furthermore, when the center of the original blur filter BF_5 is positioned at this processing target pixel, blur filter BF_5b corresponds to a filter coefficient that is modified to be smaller for pixels within the filter area of ​​blur filter BF_5 that have less ink amount than the processing target pixel. In this example of Case 2, the modified filter coefficient is also zero, but it may be modified to a value greater than zero.

[0051] In Case 3, the original blur filter BF_5 is used as is. The processing target pixel positioned at the center of this blur filter BF_5 is a background pixel, and its total ink amount is 0. Furthermore, when the center of the original blur filter BF_5 is positioned at the processing target pixel, the original filter BF_5 is used as is, because among the pixels within the filter area of ​​the blur filter BF_5, there are no pixels with less ink amount than the processing target pixel when the center of the original blur filter BF_5 is positioned at the processing target pixel.

[0052] In this way, in the third embodiment, the filter coefficient of the blurring filter is changed according to the ink amount of each pixel and its surrounding pixels, making it possible to perform blurring filter processing that takes into account the direction in which bleeding is likely to occur. In other words, it is possible to simulate a state in which high-density areas in an image do not become less dense, and bleeding into low-density areas that exist around high-density areas. The third embodiment can also be applied to the blurring filter of the second embodiment.

[0053] In the above-described embodiments, the blurring process is performed by applying a blurring filter to high-density pixels in the ink ejection region IP, but it is also possible not to apply a blurring filter to high-density pixels. Specifically, for example, edges with large density differences may be extracted, and the blurring process may be performed by applying a blurring filter only to pixels on the low-density side of the edge boundary. This case also has a common feature with the above-described embodiments in that the blurring parameter ZP is determined according to the ink amount for each pixel, and the blurring process is applied according to the blurring parameter ZP.

[0054] 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.

[0055] (1) According to a first aspect of the present disclosure, there is provided a method for creating proof image data, the method including: (a) determining ink volume image data representing an amount of ink for each pixel when a printed matter is printed on a print medium using a printing press according to input image data; (b) determining a bleeding parameter for each pixel according to the ink volume for each pixel; (c) creating bleeding-added image data by applying a bleeding-adding process to either the input image data or image data for actual printing obtained by converting the color space of the input image data into an output color space for the printing press according to the bleeding parameters; and (d) creating bleeding-added proof image data by performing a process of converting the color space of the bleeding-added image data into an output color space for a proof output device. According to this method, proof image data that simulates the bleeding state can be obtained.

[0056] (2) In the above method, the bleeding parameters may include a filter type of a blurring filter used in the bleeding process, and step (b) may include a step of selecting a filter type that provides a greater blurring effect as the amount of ink increases. According to this method, bleeding can be imparted using a blurring filter of a filter type selected according to the ink amount of each pixel.

[0057] (3) In the above method, step (c) further includes: (c1) a step of provisionally determining to apply one or more blur filters to each pixel by provisionally locating the center of a blur filter of the filter type selected according to the ink amount of each pixel at the each pixel and provisionally determining to apply the blur filter to all pixels included in the filter area of ​​the provisionally located blur filter; (c2) a step of determining to apply to each pixel one blur filter with the greatest blur effect among the one or more blur filters provisionally determined to be applied to the individual pixel in step (c1); and (c3) a step of creating the blur-added image data by applying the blur filter determined in step (c2) to the each pixel. It may also include. According to this method, bleeding can be imparted using a blurring filter determined according to the ink amount of each pixel.

[0058] (4) In the above method, step (c3) may include, when the center of the blur filter is positioned with the individual pixel as the processing target pixel, changing the filter value for each pixel within the filter area of ​​the blur filter that has a smaller amount of ink than the processing target pixel to a value smaller than the filter value when the ink amount is equal to or greater than that of the processing target pixel, and applying the changed blur filter to the processing target pixel to perform filter processing. According to this method, blurring filter processing can be performed taking into account the direction in which blurring is likely to occur.

[0059] (5) In the above method, step (b) may include a step of selecting, from among multiple types of ink used when printing the printed matter by the printing press, some inks that cause bleeding in the printed matter, and a step of determining the bleeding parameters according to the ink amounts of the selected inks. According to this method, the bleeding parameters can be determined according to the ink amount of ink that easily bleeds.

[0060] (6) In the above method, the selected ink may contain a penetrant liquid. According to this method, the bleeding parameters can be determined according to the amount of the penetrant liquid.

[0061] (7) According to a second aspect of the present disclosure, there is provided a proof image data creation device, comprising: an ink amount calculation unit that calculates ink amount image data representing an ink amount for each pixel when printing a printed material on a printing medium using a printing press according to input image data; a bleeding parameter determination unit that determines bleeding parameters for each pixel according to the ink amount for each pixel; a bleeding addition unit that creates bleeding-added image data by applying a bleeding addition process to either the input image data or image data for actual printing obtained by converting the color space of the input image data into an output color space for the printing press according to the bleeding parameters; and a color conversion unit that creates bleeding-added proof image data by performing a process of converting the color space of the bleeding-added image data into an output color space for a proof output device.

[0062] (8) According to a third aspect of the present disclosure, there is provided a computer program for creating proof image data. The computer program causes a computer to execute the following steps: (a) determining ink volume image data representing the amount of ink for each pixel when printing a printed material on a printing medium using a printing press according to input image data; (b) determining a bleeding parameter for each pixel according to the ink volume for each pixel; (c) creating bleeding-added image data by applying a bleeding-adding process to either the input image data or image data for actual printing obtained by converting the color space of the input image data into an output color space for the printing press according to the bleeding parameters; and (d) creating bleeding-added proof image data by converting the color space of the bleeding-added image data into an output color space for a proof output device.

[0063] 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]

[0064] 50...CPU, 60...storage unit, 61...proof image creation program, 70...input / output interface, 100...proof image data creation device, 110...display device, 120...ink amount calculation unit, 130...bleed parameter determination unit, 140...bleed application unit, 150...color conversion unit, 160...texture application unit, 200...proof printing device, 300...printing machine, 500...printing system

Claims

1. 1. A method for creating proof image data, comprising: (a) determining ink amount image data representing the amount of ink to be used for each pixel when printing a printed matter on a printing medium using a printing machine in accordance with input image data; (b) determining a bleeding parameter for each pixel according to the ink amount for each pixel; (c) creating bleed-added image data by applying a bleed-adding process to either the input image data or actual printing image data obtained by converting the color space of the input image data into an output color space for the printing machine, in accordance with the bleed parameters; (d) creating bleed proof image data by performing a process of converting the color space of the bleed-added image data into an output color space for a proof output device; A method comprising:

2. 10. The method of claim 1, the blur parameters include a filter type of a blur filter used in the blurring process; The method, wherein step (b) includes selecting a filter type that produces a greater blurring effect as the amount of ink increases.

3. 3. The method of claim 2, The step (c) further comprises: (c1) provisionally locating the center of a blur filter of the filter type selected according to the ink amount of each pixel at the individual pixel, and provisionally determining to apply the blur filter to all pixels included in a filter area of ​​the provisionally located blur filter, thereby provisionally determining to apply one or more blur filters to the individual pixel; (c2) determining to apply to each pixel one blur filter having the greatest blur effect among the one or more blur filters tentatively determined to be applied to the individual pixel in (c1); (c3) applying the blur filter determined in (c2) to each pixel to create the blurred image data; A method comprising:

4. 4. The method of claim 3, The step (c3) a step of changing a filter value for a pixel in the filter area of ​​the blur filter, the pixel having a smaller ink amount than the pixel being processed, to a value smaller than the filter value when the ink amount is equal to or greater than that of the pixel being processed, when the center of the blur filter is positioned with the pixel being the pixel being processed; applying the changed blur filter to the processing target pixel to perform a filter process; A method comprising:

5. 10. The method of claim 1, The step (b) selecting, from among a plurality of types of ink used when printing the printed matter by the printing machine, a portion of the ink that causes bleeding in the printed matter; determining the bleeding parameters according to the ink amounts of the selected inks; A method comprising:

6. 6. The method of claim 5, The method wherein the selected ink comprises a penetrant liquid.

7. A proof image data creation device, an ink amount calculation unit that calculates ink amount image data that represents the amount of ink for each pixel when printing a printed matter on a printing medium using a printing machine in accordance with input image data; a bleeding parameter determination unit that determines bleeding parameters for each pixel according to the ink amount for each pixel; a bleeding imparting unit that applies bleeding processing to either the input image data or the actual printing image data obtained by converting the color space of the input image data into an output color space for the printing machine, thereby creating bleeding-imparted image data; a color conversion unit that generates bleeding proof image data by performing a process of converting a color space of the bleeding-added image data into an output color space for a proof output device; A proof image data creation device comprising:

8. A computer program for creating proof image data, (a) a process for obtaining ink amount image data representing the amount of ink for each pixel when printing a printed matter on a printing medium using a printing machine in accordance with input image data; (b) determining a bleeding parameter for each pixel according to the ink amount for each pixel; (c) a process of creating bleed-added image data by applying a bleed-adding process to either the input image data or the actual printing image data obtained by converting the color space of the input image data into an output color space for the printing machine, in accordance with the bleed parameters; (d) creating bleed proof image data by converting the color space of the bleed-added image data into an output color space for a proof output device; A computer program that causes a computer to execute the following.

Images