Image printing toning method and system for different paper color backgrounds

Abstract

The invention relates to the field of printing toning, in particular to an image printing toning method and system for different paper color backgrounds. According to the method, the image sample needing to be printed, the LAB value and the background color of the image sample needing to be printed are obtained firstly, so that when the current situation exists in the color library, the corresponding ink matching parameters are called, and when the current situation does not exist in the color library, the color library is trained, and then the multiple ink matching parameters are obtained through the color library; the method comprises the following steps of: printing a corresponding physical sample according to an ink proportioning parameter, updating a color library when the physical sample meets the requirement, and continuously adjusting an LAB value when the physical sample does not meet the requirement so as to continuously modify the ink proportioning parameter, so that the physical sample is gradually close to an image sample and the physical sample closer to the image sample is automatically printed; the problem that due to the fact that an existing printing color matching system lacks accurate matching of partial colors, the partial colors have chromatic aberration compared with images provided by customers after being printed is solved.

Description

Technical Field

[0001] The present invention relates to the field of printing color matching, and specifically to an image printing color matching method and system for different paper color backgrounds. Background Art

[0002] In the printing industry, printing the image content provided by customers on different papers is a core business. However, with the enrichment of life, there are more and more personalized designs of the image content provided by customers, and their colors are becoming increasingly rich. However, when the current printing system faces some colors, color differences may occur after printing, resulting in a decrease in customer satisfaction. The main reason for this phenomenon is that the current printing color matching system lacks the precise ratio of some colors. Especially when printing on papers of different colors, the ink ratio parameters increase exponentially, so it is difficult for operators to remember such a large amount of ratio parameters, resulting in difficulty in accurately matching the corresponding color ink. Summary of the Invention

[0003] Aiming at the deficiencies of the prior art, the present invention provides an image printing color matching method and system for different paper color backgrounds, which solves the problem that the current printing color matching system lacks the precise ratio of some colors, resulting in color differences between some colors after printing and the images provided by customers.

[0004] To achieve the above object, the present invention provides the following technical solutions: An image printing color matching method and system for different paper color backgrounds, the color matching method specifically includes the following steps: S1. Obtain the image sample to be color-matched and its LAB value, as well as the background color of the paper to be printed; S2. Determine whether there is corresponding historical data in the color library according to the LAB value of the image sample and the background color of the paper; If it exists, perform color restoration and preview on the color matching system, and then enter step S3; If not, train and calibrate the color library based on historical data, and then enter step S3; S3. Obtain several ink ratio parameters closest to the LAB value of the pattern from the color library, and configure the ink cartridges to print physical samples; S4. Determine whether there is a physical sample that meets the requirements of the image sample; If it exists, save the ink ratio parameters of the image sample to the color library; If not, regenerate several ink ratio parameters according to the difference between the LAB values of the physical sample and the image sample, and then return to step S3.

[0005] Preferably, in step S1, it specifically includes the following steps: S11. Identify the RGB colors of each pixel point in the image sample; S12. Convert the RGB colors to LAB values; S13. Set the LAB segmentation threshold; S14. Divide the pixel points whose difference in LAB values between any two pixel points is less than the LAB segmentation threshold into the same color block; S15. Count the number of pixel points in any color block; S16. Select several pixel points from any color block and calculate their average LAB value as the LAB value of the color block; S17. Take the LAB value corresponding to the color block with the largest number of pixel points as the background color of the paper to be printed.

[0006] Preferably, in step S2, it specifically includes the following steps: S21. Determine whether there is corresponding historical data in the color library according to the LAB value of the image sample and the paper background color; If there is, enter step S22; If not, train and calibrate the color library based on the historical data, and then enter step S3; S22. Obtain the corresponding ink ratio parameters according to the color library; S23. Perform color balance on the color corresponding to the ink ratio parameters; S24. Adjust the curve of the result after color balance according to the parameters; S25. Perform layer blending on the result after curve adjustment according to the parameters; S26. Output the color restoration result.

[0007] Preferably, in step S3, it specifically includes the following steps: S31. Obtain several ink ratio parameters that are closest to the LAB value of the pattern from the color library, and sequentially print different physical samples through ink cartridges with different ink ratios; S32. Select the ink ratio parameter of any unprinted image for ink adjustment; S33. Send the configured ink into the ink cartridge; S34. Start the ink cartridge to start printing; S35. After printing, rinse the ink cartridge with water; S36. Determine whether all ink ratio parameters have printed corresponding physical samples; If so, enter the next step; If not, return to step S32.

[0008] Preferably, in step S4, it specifically includes the following steps: S41. Calculate the difference in LAB values between any position on the physical sample and the corresponding position on the image sample; S42. Determine whether the difference in LAB values between any position on the physical sample and the corresponding position on the image sample is less than the LAB threshold; If so, save the ink mixing ratio parameters of the image sample to the color library; If not, proceed to the next step; S43. Calculate the sum of the difference in LAB values and the LAB of the physical sample to obtain the second LAB value of the physical sample; S44. Obtain the ink mixing ratio parameters closest to the LAB value of the pattern according to the second LAB value and the color library; S45. Count the number of times entering step S44 and determine whether it is greater than the number threshold; If so, proceed to the next step; If not, return to step S32.

[0009] S46. Manually adjust the LAB value used for retrieving the ink mixing ratio parameters, and then return to step S31.

[0010] Preferably, in step S41, it specifically includes the following steps: S411. Establish a two-dimensional coordinate system with the same corner of the image sample and the physical sample as the origin; S412. Select the length and width of either the image sample or the physical sample simultaneously as the length and width of both the image sample and the physical sample; S413. Count the number of pixel points corresponding to the length and width of the selected image sample or physical sample; S414. Divide the length and width of the unselected image sample or physical sample into several grids, and the number of divisions is equal to the number of pixel points corresponding to the length and width of the selected image sample or physical sample; S415. Take any grid of the unselected image sample or physical sample as a pixel point, and set the length and width of each pixel point to 1; S416. Establish the coordinates of any pixel point on the image sample and the physical sample according to the two-dimensional coordinate system; S417. Calculate the difference in LAB values between the pixel point at any coordinate on the physical sample and the pixel point at the corresponding coordinate on the image sample.

[0011] This technical solution also provides a system for implementing an image printing color adjustment method for different paper color backgrounds. The system includes: a processor and a memory. The memory is used to store a computer program, and when the computer program is executed by the processor, it implements the image printing color adjustment method for different paper color backgrounds.

[0012] Compared with the prior art, the present invention provides an image printing color adjustment method and system for different paper color backgrounds, having the following beneficial effects: 1. The present invention first obtains an image sample to be printed, its LAB value, and its background color. Thus, when the current situation exists in the color library, the corresponding ink ratio parameters are retrieved. When it does not exist, the color library is trained, and then several ink ratio parameters are obtained through the color library. Thus, a corresponding physical sample can be printed according to the ink ratio parameters. When the physical sample meets the requirements, the color library is updated. When the physical sample does not meet the requirements, the LAB value is continuously adjusted to continuously modify the ink ratio parameters, so as to gradually approach the image sample and automatically print a physical sample closer to the image sample.

[0013] 2. The present invention sets a LAB segmentation threshold to enable different pixel points to be aggregated into several color blocks according to the LAB value, and the background color is identified according to the number of pixel points in the color blocks, thus facilitating the subsequent color adjustment system to automatically retrieve the corresponding ink ratio parameters.

[0014] 3. When comparing the image sample and the physical sample, in order to ensure the consistency of their positions on the image when comparing their LAB values, a two-dimensional coordinate system is established, and one of the image samples or physical samples is equally divided along the x-axis and y-axis, so as to ensure that the corresponding image positions of the same coordinates are the same when comparing. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings described herein are used to provide a further understanding of the present application and form a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation to the present application. In the drawings: Figure 1 is a flowchart of the image printing color adjustment method for different paper color backgrounds of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0016] In order to make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the drawings and specific embodiments. Thereby, the implementation process of how the present application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0017] Those of ordinary skill in the art can understand that all or part of the steps in implementing the following embodiment methods can be completed by instructing relevant hardware through a program. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories, CD-ROMs, optical memories, etc.) containing computer-usable program codes.

[0018] To solve the problem that the current printing color matching system lacks the precise ratio of some colors, resulting in color differences between some printed colors and the images provided by customers, the present invention provides an image printing color matching method for different paper color backgrounds. As the printing equipment is used, the ink ratio parameters in the color library of the printing equipment become increasingly rich and precise, thereby continuously improving the degree of approximation to the colors of the images provided by customers and continuously enhancing customer satisfaction. The specific steps of this color matching method are as follows: S1. Obtain the image sample to be color-matched and its LAB value, as well as the background color of the paper to be printed; the LAB value is converted from the RGB color. Through this method, it is possible to accurately determine whether the product color meets the expected requirements. The advantage of the Lab color model is its wide color gamut, which can represent colors that the RGB and CMYK color models cannot represent. In step S1, it specifically includes the following steps: S11. Identify the RGB colors of each pixel point in the image sample; S12. Convert the RGB color to the LAB value; S13. Set the LAB segmentation threshold; S14. Divide the pixel points with the difference between the LAB values of any two pixel points less than the LAB segmentation threshold into the same color block; the LAB value includes the L value, A value, and B value. Here, there are 3 LAB segmentation thresholds, corresponding to the L value, A value, and B value respectively; S15. Count the number of pixel points in any color block; S16. Select several pixel points from any color block and calculate their average LAB value as the LAB value of this color block; S17. Take the LAB value corresponding to the color block with the largest number of pixel points as the background color of the paper to be printed.

[0019] S2. Determine whether there is corresponding historical data in the color library according to the LAB value of the image sample and the background color of the paper; If it exists, perform color restoration and preview on the color matching system, and then enter step S3; If not, train and calibrate the color library based on historical data, and then proceed to step S3; the method of training and calibrating the color library using historical data is to train with the aid of a neural network model; When the color library contains the situation corresponding to the LAB value of the current image and the paper background color, retrieve the ink ratio parameters corresponding to the current situation from the color library. However, before printing, it is necessary to preview it first to avoid errors. In step S2, it specifically includes the following steps: S21. Determine whether there is corresponding historical data in the color library according to the LAB value of the image sample and the paper background color; If so, proceed to step S22; If not, train and calibrate the color library based on historical data, and then proceed to step S3; S22. Obtain the corresponding ink ratio parameters according to the color library; S23. Perform color balance on the color corresponding to the ink ratio parameters; S24. Adjust the curve of the result after color balance according to the parameters; S25. Perform layer blending on the result after curve adjustment according to the parameters; S26. Output the color restoration result.

[0020] S3. Obtain several ink ratio parameters that are closest to the LAB value of the pattern from the color library, and configure the ink cartridges to print physical samples; in order to select the physical sample with the color closest to the pattern sample and the corresponding ink ratio parameters, in step S3, it specifically includes the following steps: S31. Obtain several ink ratio parameters that are closest to the LAB value of the pattern from the color library, and print different physical samples with ink cartridges of different ink ratios in turn; S32. Select the ink ratio parameter of any unprinted image for ink mixing; S33. Feed the configured ink into the ink cartridge; S34. Start the ink cartridge to print; S35. After printing, rinse the ink cartridge with water; S36. Determine whether physical samples corresponding to all ink ratio parameters have been printed; If so, proceed to the next step; If not, return to step S32.

[0021] S4. Determine whether there is a physical sample that meets the requirements of the image sample; If so, save the ink ratio parameters of the image sample to the color library; If not, regenerate several ink ratio parameters according to the difference in LAB values between the physical sample and the image sample, and then return to step S3. To enable the system to automatically identify whether the image sample is similar to the physical sample after printing an image sample, in step S4, it specifically includes the following steps: S41. Calculate the difference in LAB values at any position on the physical sample and the corresponding position on the image sample; By calculating the difference in LAB values at any position on the physical sample and the corresponding position on the image sample, the similarity of the LAB values at any coordinate of the two can be reflected. However, the number of pixel points in the two images may be different, so the same position in the two may correspond to different patterns. Therefore, to ensure the consistency of the objects at the same position, in step S41, it specifically includes the following steps: S411. Establish a two-dimensional coordinate system with the same corner of the image sample and the physical sample as the origin; S412. Select the length and width of either the image sample or the physical sample simultaneously as the length and width of both the image sample and the physical sample; S413. Count the number of pixel points corresponding to the selected length and width of the image sample or the physical sample; S414. Divide the length and width of the unselected image sample or physical sample into several grids. The number of divisions is equal to the number of pixel points corresponding to the selected length and width of the image sample or the physical sample; S415. Take any grid on the unselected image sample or physical sample as a pixel point, and set the length and width of each pixel point to 1; S416. Establish the coordinates of any pixel point on the image sample and the physical sample according to the two-dimensional coordinate system; S417. Calculate the difference in LAB values between the pixel point at any coordinate on the physical sample and the pixel point at the corresponding coordinate on the image sample.

[0022] S42. Determine whether the difference in LAB values at any position on the physical sample and the corresponding position on the image sample is less than the LAB threshold; If so, save the ink ratio parameters of this image sample to the color library; If not, proceed to the next step; S43. Calculate the sum of the difference in LAB values and the LAB of the physical sample to obtain the second LAB value of the physical sample; S44. Obtain the ink ratio parameter closest to the LAB value of the pattern according to the second LAB value and the color library; S45. Count the number of times entering step S44 and determine whether it is greater than the number threshold; If so, proceed to the next step; If not, return to step S32.

[0023] S46. Manually adjust the LAB value for retrieving ink ratio parameters, and then return to step S31.

[0024] The present invention first obtains the image sample to be printed, the LAB value, and its background color, so as to retrieve the corresponding ink ratio parameters when the current situation exists in the color library. When it does not exist, the color library is trained, and then several ink ratio parameters are obtained through the color library, so that the corresponding physical sample can be printed according to the ink ratio parameters. When the physical sample meets the requirements, the color library is updated. When the physical sample does not meet the requirements, the LAB value is continuously adjusted to continuously modify the ink ratio parameters, so as to gradually approach the image sample and automatically print a physical sample closer to the image sample.

[0025] The present invention also provides an image printing color adjustment system for different paper color backgrounds, including a processor and a memory. The memory is used to store a computer program, and when the computer program is executed by the processor, an image printing color adjustment method for different paper color backgrounds is implemented.

[0026] The above embodiments have introduced the present invention in detail. Specific examples are used in this article to elaborate on the principle and implementation of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. An image printing color adjustment method and system for different paper color backgrounds, characterized in that, The color adjustment method specifically includes the following steps: S1. Obtain the image sample to be color-adjusted and its LAB values, as well as the background color of the paper to be printed; S2. Determine whether there is corresponding historical data in the color library based on the LAB values of the image sample and the background color of the paper; If there is, perform color restoration and preview on the color adjustment system, and then proceed to step S3; If not, train and calibrate the color library based on historical data, and then proceed to step S3; S3. Obtain several ink ratio parameters that are closest to the LAB values of the pattern from the color library, and configure the ink cartridges to print physical samples; S4. Determine whether there is a physical sample that meets the requirements of the image sample; If there is, save the ink ratio parameters of the image sample to the color library; If not, regenerate several ink ratio parameters according to the difference between the LAB values of the physical sample and the image sample, and then return to step S3.

2. The color adjustment method according to claim 1, wherein In step S1, it specifically includes the following steps: S11. Identify the RGB colors of each pixel point in the image sample; S12. Convert the RGB colors to LAB values; S13. Set the LAB segmentation threshold; S14. Divide the pixel points with the difference between the LAB values of any two pixel points less than the LAB segmentation threshold into the same color block; S15. Count the number of pixel points in any color block; S16. Select several pixel points from any color block, and calculate their average LAB value as the LAB value of the color block; S17. Use the LAB value corresponding to the color block with the largest number of pixel points as the background color of the paper to be printed.

3. The color adjustment method according to claim 1, wherein In step S2, it specifically includes the following steps: S21. Determine whether there is corresponding historical data in the color library based on the LAB values of the image sample and the background color of the paper; If there is, proceed to step S22; If not, train and calibrate the color library based on historical data, and then proceed to step S3; S22. Obtain the corresponding ink ratio parameters according to the color library; S23. Perform color balance on the colors corresponding to the ink ratio parameters; S24. Adjust the curve of the color-balanced result according to the parameters; S25. Perform layer blending on the curve-adjusted result according to the parameters; S26. Output the color restoration result.

4. The color adjustment method according to claim 1, characterized in that In step S3, it specifically includes the following steps: S31. Obtain several ink ratio parameters that are closest to the LAB values of the pattern from the color library, and sequentially print different physical samples with ink cartridges of different ink ratios; S32. Select the ink ratio parameter of any unprinted image for ink adjustment; S33. Feed the configured ink into the ink cartridge; S34. Start the ink cartridge to start printing; S35. After printing is completed, rinse the ink cartridge with water; S36. Determine whether all ink ratio parameters have printed corresponding physical samples; If so, proceed to the next step; If not, return to step S32.

5. The color adjustment method according to claim 1, characterized in that, In step S4, it specifically includes the following steps: S41. Calculate the difference between the LAB values at any position on the physical sample and the corresponding position on the image sample; S42. Determine whether the difference between the LAB values at any position on the physical sample and the corresponding position on the image sample is less than the LAB threshold; If so, save the ink ratio parameters of the image sample to the color library; If not, proceed to the next step; S43. Calculate the difference in LAB values and the sum of LAB values of the physical sample to obtain the second LAB value of the physical sample; S44. Obtain the ink ratio parameters closest to the LAB value of the pattern according to the second LAB value and the color library; S45. Count the number of times of entering step S44 and determine whether it is greater than the threshold number of times; If so, proceed to the next step; If not, return to step S32.

6. S46. Manually adjust the LAB value used for retrieving the ink ratio parameters, and then return to step S31.

7. The color adjustment method according to claim 5, characterized in that In step S41, it specifically includes the following steps: S411. Establish a two-dimensional coordinate system with the same corner of the image sample and the physical sample as the origin; S412. Select the length and width of any one of the image sample or the physical sample as the length and width of both the image sample and the physical sample; S413. Count the number of pixel points corresponding to the length and width of the selected image sample or physical sample; S414. Divide the length and width of the unselected image sample or physical sample into several grids, and the number of divisions is equal to the number of pixel points corresponding to the length and width of the selected image sample or physical sample; S415. Take any grid on the unselected image sample or physical sample as a pixel point, and set the length and width of each pixel point to 1; S416. Establish the coordinates of any pixel point on the image sample and the physical sample according to the two-dimensional coordinate system; S417. Calculate the difference in LAB values between the pixel point at any coordinate on the physical sample and the pixel point at the corresponding coordinate on the image sample.

8. A color adjustment system for implementing the color adjustment method according to any one of claims 1-6 above, characterized in that, It includes a processor and a memory, and the memory is used to store a computer program. When the computer program is executed by the processor, it implements the image printing color adjustment method for different paper color backgrounds as described in any one of claims 1-6.

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