White ink quantity setting method and device based on inverse color gray value, equipment and medium

Abstract

The invention discloses a white ink quantity setting method, device and equipment based on an inverse color gray value and a medium, and the method comprises the steps: obtaining the value of the gray value of each pixel point after the gray processing of a color image, and recording the value as the inverse color gray value; obtaining an actual mapping relation between the inverse color gray value and the white ink quantity value of each pixel point; and according to the inverse color gray value of each pixel point and the actual mapping relation, obtaining a white ink quantity value for bottoming each pixel point of the color image before printing the color image. According to the invention, the multi-dimensional color values are converted into the one-dimensional gray values which can be directly compared, and the gray values are reversed, so that the bottomed white ink and the color ink in the color image are mutually complementary, and the printed color image is brighter in color and more layered; and meanwhile, the problem that the air permeability of a cloth printing medium is poor due to the fact that all pixel points adopt the same white ink concentration for bottoming is solved.

Description

[0001] This application is a divisional application of the invention patent application with the application number 201910517305.2, titled "Method, Device, Equipment and Medium for Automatically Setting White Ink Amount Pixel by Pixel in Images", which was filed on June 14, 2019. Technical Field

[0002] The present invention relates to the field of printing technology, and in particular to a method, device, equipment and medium for setting the amount of white ink based on the anti-color gray value. Background Art

[0003] An inkjet printer sprays fine droplets of colored liquid ink onto the printing medium through nozzles. However, in some special application scenarios, if a color image needs to be printed, a layer of white ink needs to be printed on a non-white printing medium for laying the base, so that the expressiveness of the color image will be better. For example, in the field of textile digital printing, a layer of white ink with a concentration of 100% needs to be printed for laying the base before printing a color image; but directly printing white ink with a concentration of 100% without considering the color and material of the printing medium will not only result in a weak sense of hierarchy in the printed color image, but also waste white ink. In the textile industry, it is often necessary to print fabrics with relatively thin materials such as silk fabrics. At this time, if white ink with a concentration of 100% is directly printed for laying the base, it will cause the white ink concentration to be too thick, the air permeability of the fabric to become poor, and the product quality to decline. Summary of the Invention

[0004] Embodiments of the present invention provide a method, device, equipment and medium for setting the amount of white ink based on the anti-color gray value, so as to solve the problem of single white ink concentration for laying the base when printing color images in the prior art and poor printing product quality.

[0005] In a first aspect, an embodiment of the present invention provides a method for setting the amount of white ink based on the anti-color gray value, the method including:

[0006] Obtaining the value after anti-color processing of the gray value of each pixel point after gray-scale processing of the color image, denoted as the anti-color gray value;

[0007] Obtaining the initial mapping relationship between the anti-color gray value of each pixel point and the white ink amount value;

[0008] Selecting n anti-color gray values from the anti-color gray values as sample anti-color gray values, where n≥1 and n is an integer;

[0009] Comparing the sample anti-color gray values with a preset gray threshold to obtain a comparison result;

[0010] Adjusting the initial mapping relationship according to the comparison result to obtain the actual mapping relationship;

[0011] Obtain the white ink amount value for underlaying each pixel of the color image before printing the color image according to the anti-color gray value of each pixel and the actual mapping relationship.

[0012] Preferably, the obtaining of the initial mapping relationship between the anti-color gray value of each pixel and the white ink amount value includes:

[0013] Obtain the initial mapping relationship according to the following formula: W = H, where W is the white ink amount value and H is the anti-color gray value.

[0014] Preferably, the obtaining of the actual mapping relationship by adjusting the initial mapping relationship according to the comparison result includes:

[0015] Automatically adjust the initial mapping relationship according to the comparison result by calling an adjustment program in the memory to obtain the actual mapping relationship.

[0016] Preferably, the adjustment program includes: when the anti-color gray values of most pixels in the color image are less than the preset gray threshold, the white ink amount values corresponding to all the anti-color gray values less than the preset gray threshold should be correspondingly reduced, and the white ink amount values corresponding to all the anti-color gray values greater than the preset gray threshold should be correspondingly increased.

[0017] Preferably, n = 1, and the sample anti-color gray value is the anti-color gray value corresponding to the most pixels.

[0018] Preferably, when n > 1, the selecting of n anti-color gray values from the anti-color gray values as sample anti-color gray values includes:

[0019] Sort all the anti-color gray values in descending order according to the number of corresponding pixels to obtain an anti-color gray value sequence list;

[0020] Select n anti-color gray values from the anti-color gray value sequence list in descending order, and the n anti-color gray values are the sample anti-color gray values.

[0021] Preferably, after obtaining the white ink amount value for underlaying each pixel of the color image before printing the color image according to the anti-color gray value of each pixel and the actual mapping relationship, it further includes:

[0022] Perform white ink underlay printing according to the white ink amount value, and then perform color printing according to the color ink amount.

[0023] In a second aspect, an embodiment of the present invention provides a white ink amount setting device based on anti-color gray values, and the device includes:

[0024] An inverse-color grayscale value acquisition module, configured to obtain the value after inverse-color processing of the grayscale values of each pixel point after the color image is grayscaled, denoted as the inverse-color grayscale value;

[0025] An initial mapping relationship acquisition module, configured to always obtain the initial mapping relationship between the inverse-color grayscale value of each pixel point and the white ink amount value;

[0026] A selection module, configured to select n inverse-color grayscale values from the inverse-color grayscale values as sample inverse-color grayscale values, where n≥1 and n is an integer;

[0027] A comparison module, configured to compare the sample inverse-color grayscale value with a preset grayscale threshold to obtain a comparison result;

[0028] An actual mapping relationship acquisition module, configured to adjust the initial mapping relationship according to the comparison result to obtain the actual mapping relationship;

[0029] A white ink amount setting module, configured to obtain the white ink amount value for underlaying each pixel point of the color image before printing the color image according to the inverse-color grayscale value of each pixel point and the actual mapping relationship.

[0030] In a third aspect, an embodiment of the present invention provides a white ink amount setting device based on inverse-color grayscale values, including: at least one processor, at least one memory, and computer program instructions stored in the memory, which implement the method in the first aspect of the above-mentioned implementation manner when the computer program instructions are executed by the processor.

[0031] In a fourth aspect, an embodiment of the present invention provides a storage medium, on which computer program instructions are stored, which implement the method in the first aspect of the above-mentioned implementation manner when the computer program instructions are executed by the processor.

[0032] In summary, the white ink amount setting method, device, equipment, and medium based on inverse-color grayscale values provided by the embodiments of the present invention automatically obtain the white ink amount value corresponding to each pixel point in the color image through the actual mapping relationship between the inverse-color grayscale value and the white ink amount value. The method is simple and fast, and the white ink amount value for underlaying each pixel point is set according to the actual color value of each pixel point in the color image, ensuring that the white ink amount values for underlaying each pixel point are different, avoiding the problem of poor product quality caused by directly printing with the same white ink amount value in the industrial inkjet printing industry. At the same time, setting the underlaying white ink in this way is complementary to the color ink in the color image, making the printed color image more vivid in color and more layered in image, and also avoiding the problem of poor air permeability of the fabric printing medium caused by using the same white ink concentration for underlaying all pixel points. Description of the Drawings

[0033] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the accompanying drawings required for use in the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0034] Figure 1 is a flowchart of the method for automatically setting the white ink amount per pixel of the image in the first embodiment of the present invention.

[0035] Figure 2 is a flowchart of the method for automatically setting the white ink amount per pixel of the image in the second embodiment of the present invention.

[0036] Figure 3 is a flowchart of the method for automatically setting the white ink amount per pixel of the image in the third embodiment of the present invention.

[0037] Figure 4 is a schematic diagram of the mapping relationship of the method for automatically setting the white ink amount per pixel of the image in the third embodiment of the present invention.

[0038] Figure 5 is a flowchart of the method for automatically setting the white ink amount per pixel of the image in the fourth embodiment of the present invention.

[0039] Figure 6 is a schematic diagram of the mapping relationship of the method for automatically setting the white ink amount per pixel of the image in the fourth embodiment of the present invention.

[0040] Figure 7 is a schematic structural diagram of the device for automatically setting the white ink amount per pixel of the image in the embodiments of the present invention.

[0041] Figure 8 is a schematic structural diagram of the device for automatically setting the white ink amount per pixel of the image in the embodiments of the present invention. Detailed Embodiments

[0042] The following will describe in detail the features and exemplary embodiments of various aspects of the present invention. To make the objectives, technical solutions, and advantages of the present invention clearer, the following further describes the present invention in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present invention and are not configured to limit the present invention. For those skilled in the art, the present invention can be implemented without some of these specific details. The following description of the embodiments is only to provide a better understanding of the present invention by showing examples of the present invention.

[0043] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0044] Please refer to Figure 1 , an embodiment of the present invention provides an automatic white ink amount setting method for each pixel of an image, and the method specifically includes the following steps:

[0045] S1. Obtain the value after inverse color processing of the gray value of each pixel point after graying the color image, and record it as the inverse color gray value;

[0046] Specifically, traverse all pixel points in the color image, obtain the actual color value of each pixel point, perform graying processing on the actual color value to obtain the gray value of each pixel point, and perform inverse color processing on the gray value of each pixel point to obtain the inverse color gray value of each pixel point. Among them, the representation of the actual color value is different in different color gamuts. For example, in the CMYK color gamut, the actual color value of a pixel point is determined by four colors: cyan (C), magenta (M), yellow (Y), and black (K), so the actual color value of a certain pixel point is (C, M, Y, K); in the RGB color gamut, the actual color value is (R, G, B). The graying processing of the color image is also different in different color gamuts. The formula for graying processing of the color image in the CMYK color gamut is:

[0047]

[0048] where Gray represents the gray value, and the actual color value of the pixel point is (C, M, Y, K);

[0049] The formula for graying processing of the color image in the RGB color gamut is:

[0050] Gray = R × 0.299 + G × 0.587 + B × 0.114

[0051] where Gray represents the gray value, and the actual color value of the pixel point is (R, G, B);

[0052] After obtaining the grayscale value of each pixel, perform color inversion on the grayscale value to obtain the color-inverted grayscale value of each pixel. The calculation method of the color-inverted grayscale value is as follows:

[0053] H = 255 - Gray

[0054] Where H is the color-inverted grayscale value and Gray is the grayscale value.

[0055] S2. Obtain the actual mapping relationship between the color-inverted grayscale value of each pixel and the white ink amount value;

[0056] Please refer to Figure 2 , in this embodiment, the actual mapping relationship is obtained by the following method:

[0057] S211. Obtain the initial mapping relationship between the color-inverted grayscale value of each pixel and the white ink amount value;

[0058] S212. Obtain the initial white ink amount value corresponding to each pixel when printing the color image according to the color-inverted grayscale value of each pixel and the initial mapping relationship;

[0059] S213. Perform inkjet printing according to the initial white ink amount value and color ink amount value of each pixel to obtain a calibration image;

[0060] S214. Obtain an adjustment coefficient for adjusting the initial mapping relationship according to the calibration image and the color image;

[0061] S215. Adjust the initial mapping relationship according to the adjustment coefficient to obtain the actual mapping relationship.

[0062] Specifically, an initial mapping relationship between the anti-color gray value and the white ink amount value is set. The initial mapping relationship is set according to actual printing requirements. In this embodiment, the initial mapping relationship is: W = H, where W is the white ink amount value and H is the anti-color gray value. The white ink amount value is equal to the anti-color gray value and changes with the change of the anti-color gray value. In another embodiment, the initial mapping relationship is: W = 100%, where W is the white ink amount value, and in this embodiment, the white ink amount values of all pixel points are equal. After obtaining the initial mapping relationship, the initial white ink amount value corresponding to each pixel point can be calculated according to the anti-color gray value of each pixel point in the obtained color image. Printing is performed based on the white ink amount value and the color ink amount value of each pixel point to obtain a first calibration image, where the color ink amount value is the ink amount value of four colors of ink, namely cyan (C), magenta (M), yellow (Y), and black (K), which reflect the color of the pixel point. Then, the printed calibration image is scanned to obtain the color value of each pixel point in the calibration image. An error calculation is performed between the color value of each pixel point in the calibration image and the color value of the corresponding pixel point in the color image to obtain an adjustment coefficient for adjusting the initial mapping relationship. The initial mapping relationship is adjusted according to the adjustment coefficient to obtain an actual mapping relationship. Among them, the calibration image can also be observed manually, and then compared with the color image, and the initial mapping relationship is adjusted according to experience. However, manual observation has large errors and low efficiency.

[0063] Please refer to Figure 3 , and the specific steps for obtaining the adjustment coefficient include the following steps:

[0064] S2141. Scan the calibration image and perform gray-scale processing to obtain the gray value of each pixel point in the calibration image, denoted as the first gray value;

[0065] S2142. Obtain the gray value of each pixel point after gray-scale processing of the color image, denoted as the second gray value;

[0066] S2143. Compare the first gray value and the second gray value to obtain an adjustment coefficient for adjusting the initial mapping relationship.

[0067] Specifically, scan the calibration image, then import the scanned image into image processing software, and at the same time call the grayscale processing program from the memory to perform grayscale processing on the image. Then, perform color inversion processing to obtain one-dimensional color-inverted grayscale values. The calibration image and the color image are only different in color, with the same size, number of pixels, and each pixel corresponding one by one. Then, calculate the difference between the color-inverted grayscale values of each pixel in the color image and the color-inverted grayscale values of each pixel in the scanned calibration image to obtain the adjustment coefficient corresponding to each pixel, establish an adjustment mapping relationship between the adjustment coefficient and the color-inverted grayscale values of the color image, and perform quadratic polynomial fitting and smoothing processing on the initial mapping relationship and the adjustment mapping relationship to obtain the actual mapping relationship.

[0068] Please refer to Figure 4 , when the initial mapping relationship is as Figure 4 in (1): W = H, after adjustment by the adjustment coefficient, the actual mapping relationship is as Figure 4 in (2). Then, at this time, the actual mapping relationship is represented by a smooth curve, and the mathematical expression of the smooth curve is: W = aH 2 + bH + c, where H is the color-inverted grayscale value, W is the white ink amount value, and a, b, c are natural numbers and a ≠ 0; as Figure 4 in (3), at this time, the actual mapping relationship is represented by a broken line, and the mathematical expression of the broken line is:

[0069]

[0070] where H is the color-inverted grayscale value, W is the white ink amount value, and a1, a2, a3 are natural numbers. The representations of the actual mapping relationships obtained according to the different adjustment coefficients are also different.

[0071] Please refer to Figure 5 , in this embodiment, the actual mapping relationship can also be obtained by the following method:

[0072] S221. Obtain the initial mapping relationship between the color-inverted grayscale value of each pixel and the white ink amount value;

[0073] S222. Select n values from the color-inverted grayscale values as sample color-inverted grayscale values, where n ≥ 1 and n is an integer;

[0074] S223. Compare the sample color-inverted grayscale values with a preset grayscale threshold to obtain a comparison result;

[0075] S224. Adjust the initial mapping relationship according to the comparison result to obtain the actual mapping relationship.

[0076] Specifically, an initial mapping relationship between the inverse color gray value and the white ink amount value is set. The initial mapping relationship is set according to actual printing requirements. In this embodiment, the initial mapping relationship is: W = H, where W is the white ink amount value and H is the inverse color gray value. The white ink amount value is equal to the inverse color gray value and changes with the change of the inverse color gray value. In another embodiment, the initial mapping relationship is: W = 100%, where W is the white ink amount value, and the white ink amount values of all pixel points are equal in this embodiment. Then, n inverse color gray values are selected from the inverse color gray values as sample inverse color gray values, and the sample inverse color gray values are compared with the preset gray threshold to obtain a comparison result. For example, the inverse color gray value corresponding to the most pixel points is selected as the sample inverse color gray value. If the sample inverse color gray value is 102 and the gray threshold is 128, then the sample inverse color gray value is less than the gray threshold. According to this comparison result, an adjustment program in the memory is called to automatically adjust the initial mapping relationship to obtain the actual mapping relationship as Figure 6 , adjustment programs in different forms are stored in the memory. For example, in this embodiment, the gray threshold is 128. When the inverse color gray values of most pixel points in the color image are less than this threshold, the white ink amount values corresponding to all inverse color gray values less than 128 should be correspondingly reduced, and the white ink amount values corresponding to all inverse color gray values greater than 128 should be correspondingly increased. This makes the printed image transition more uniform and has better color expressiveness. At the same time, in another embodiment, the inverse color gray values are sorted according to the number of corresponding pixel points from more to less, and then the top 20 inverse color gray values corresponding to the number of pixel points are selected as sample inverse color gray values. The 20 sample inverse color gray values are compared with the gray threshold such as 128 to obtain the distribution of the sample inverse color gray values. Different adjustment coefficients are obtained according to different distributions, and the initial mapping relationship is adjusted according to the adjustment coefficients to obtain the actual mapping relationship. The gray threshold is set according to requirements and the medium material, and no specific limitation is made here.

[0077] S3. Obtain the white ink amount value for underlaying each pixel point of the color image before printing the color image according to the inverse color gray value of each pixel point and the actual mapping relationship.

[0078] Specifically, the white ink amount value corresponding to each pixel point is calculated through the actual mapping relationship according to the inverse color gray values of all pixel points in the color image. White ink underlay printing is performed according to the white ink amount value, and then color printing is performed according to the color ink amount. In this way, the printed color image has brighter colors and more vivid layers, and at the same time, it avoids the problem of poor air permeability of the fabric printing medium caused by using the same white ink concentration for all pixel points for underlaying.

[0079] Please refer to Figure 7 , an image-by-pixel white ink amount automatic setting device is provided in an embodiment of the present invention. The device includes:

[0080] An inverse color gray value acquisition module 10 is configured to acquire the values of the gray values of each pixel point after graying processing of the color image through color development, denoted as inverse color gray values;

[0081] An actual mapping relationship acquisition module 20 is configured to acquire the actual mapping relationship between the inverse color gray value of each pixel point and the white ink amount value;

[0082] A white ink amount setting module 30 is configured to obtain the white ink amount values for underlaying each pixel point of the color image before printing the color image according to the inverse color gray value of each pixel point and the actual mapping relationship.

[0083] Preferably, the actual mapping relationship acquisition module 20 includes:

[0084] A first initial mapping relationship acquisition unit is configured to acquire the initial mapping relationship between the inverse color gray value of each pixel point and the white ink amount value;

[0085] An initial white ink amount value acquisition unit is configured to acquire the initial white ink amount value corresponding to each pixel point when printing the color image according to the inverse color gray value of each pixel point and the initial mapping relationship;

[0086] A calibration image acquisition unit is configured to perform inkjet printing according to the initial white ink amount value and the color ink amount value of each pixel point to obtain a calibration image;

[0087] An adjustment coefficient acquisition unit is configured to acquire an adjustment coefficient for adjusting the initial mapping relationship according to the calibration image and the color image;

[0088] A first actual mapping relationship acquisition unit is configured to adjust the initial mapping relationship according to the adjustment coefficient to obtain the actual mapping relationship.

[0089] Preferably, acquiring the adjustment coefficient for adjusting the initial mapping relationship according to the calibration image and the color image includes:

[0090] Scanning the calibration image and performing graying processing to obtain the gray values of each pixel point in the calibration image, denoted as first gray values;

[0091] Acquiring the gray values of each pixel point after graying processing of the color image, denoted as second gray values;

[0092] Comparing the first gray value and the second gray value to acquire an adjustment coefficient for adjusting the initial mapping relationship.

[0093] Preferably, the actual mapping relationship acquisition module 20 further includes:

[0094] The second initial mapping relationship obtaining unit is configured to obtain an initial mapping relationship between the inverted gray value and the white ink amount value of each pixel point;

[0095] The sample inverted gray value obtaining unit is configured to select n values from the inverted gray values as sample inverted gray values, where n≥1 and n is an integer;

[0096] The comparison result obtaining unit is configured to compare the sample inverted gray value with a gray threshold to obtain a comparison result;

[0097] The second actual mapping relationship obtaining unit is configured to adjust the initial mapping relationship according to the comparison result to obtain the actual mapping relationship.

[0098] Preferably, n = 1, and the sample inverted gray value is the inverted gray value corresponding to the most pixel points.

[0099] Preferably, if n>1, then selecting n inverted gray values from the inverted gray values as sample inverted gray values includes:

[0100] Sorting all the inverted gray values in descending order according to the number of corresponding pixel points to obtain an inverted gray value sequence list;

[0101] Selecting n inverted gray values from the inverted gray value sequence list in descending order, and the n inverted gray values are the sample inverted gray values.

[0102] Preferably, the actual mapping relationship is represented by a smooth curve or a broken line. The abscissa of the smooth curve or the broken line is the inverted gray value, and the ordinate is the white ink amount value. The broken line includes at least two line segments.

[0103] In addition, the per-pixel white ink amount automatic setting method of the embodiment of the present invention described in Figure 1 can be implemented by a per-pixel white ink amount automatic setting device. Figure 8 FIG. shows a schematic hardware structure diagram of a per-pixel white ink amount automatic setting device provided by an embodiment of the present invention.

[0104] The per-pixel white ink amount automatic setting device may include a processor 401 and a memory 402 storing computer program instructions.

[0105] Specifically, the above-mentioned processor 401 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiment of the present invention.

[0106] The memory 402 may include a mass storage for data or instructions. By way of example and not limitation, the memory 402 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive, or a combination of two or more of these. In a suitable case, the memory 402 may include removable or non-removable (or fixed) media. In a suitable case, the memory 402 may be internal or external to the data processing device. In a particular embodiment, the memory 402 is a non-volatile solid-state memory. In a particular embodiment, the memory 402 includes a read-only memory (ROM). In a suitable case, the ROM may be a mask-programmed ROM, a programmable ROM (PROM), an erasable PROM (EPROM), an electrically erasable PROM (EEPROM), an electrically rewritable ROM (EAROM), or a flash memory, or a combination of two or more of these.

[0107] The processor 401 reads and executes the computer program instructions stored in the memory 402 to implement any one of the image per-pixel white ink amount automatic setting methods in the above embodiments.

[0108] In one example, the image per-pixel white ink amount automatic setting device may further include a communication interface 403 and a bus 410. Among them, as Figure 8 shown, the processor 401, the memory 402, and the communication interface 403 are connected through the bus 410 and complete communication with each other.

[0109] The communication interface 403 is mainly used to implement communication between each module, device, unit, and / or device in the embodiments of the present invention.

[0110] The bus 410 includes hardware, software, or both, and couples the components of the image per-pixel white ink amount automatic setting device to each other. By way of example and not limitation, the bus may include an accelerated graphics port (AGP) or other graphics bus, an enhanced industry standard architecture (EISA) bus, a front-side bus (FSB), a hypertransport (HT) interconnect, an industry standard architecture (ISA) bus, an infinite bandwidth interconnect, a low pin count (LPC) bus, a memory bus, a microchannel architecture (MCA) bus, a peripheral component interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a serial advanced technology attachment (SATA) bus, a video electronics standards association local (VLB) bus, or other suitable buses, or a combination of two or more of these. In a suitable case, the bus 410 may include one or more buses. Although the embodiments of the present invention describe and illustrate specific buses, the present invention contemplates any suitable bus or interconnect.

[0111] In addition, in combination with the method for automatically setting the white ink amount for each pixel of the image in the above embodiments, an embodiment of the present invention can provide a computer-readable storage medium to implement. Computer program instructions are stored on the computer-readable storage medium; when the computer program instructions are executed by a processor, any one of the methods for automatically setting the white ink amount for each pixel of the image in the above embodiments is implemented.

[0112] In summary, the method, device, equipment and medium for automatically setting the white ink amount for each pixel of the image provided by the embodiment of the present invention, the method automatically obtains the white ink amount value corresponding to each pixel in the color image through the actual mapping relationship between the inverted gray value and the white ink amount value. This method is simple and fast, and the white ink amount value for laying the bottom of each pixel is set according to the actual color value of each pixel in the color image, ensuring that the white ink amount values for laying the bottom of each pixel are different, avoiding the problem of poor product quality caused by directly printing with the same white ink amount value in the industrial inkjet printing industry. At the same time, setting the white ink for laying the bottom in this way and the color ink in the color image complement each other, making the printed color image more vivid in color and the image more layered. At the same time, it also avoids the problem of poor air permeability of the fabric printing medium caused by laying the bottom with the same white ink concentration for all pixels.

[0113] It should be clear that the present invention is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present invention is not limited to the specific steps described and shown. Those skilled in the art can make various changes, modifications and additions, or change the order between steps after understanding the spirit of the present invention.

[0114] The functional blocks shown in the above block diagrams can be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application-specific integrated circuit (ASIC), appropriate firmware, a plug-in, a function card, etc. When implemented in software, the elements of the present invention are programs or code segments used to execute the required tasks. The program or code segment can be stored in a machine-readable medium, or transmitted via a data signal carried in a carrier wave on a transmission medium or a communication link. "Machine-readable medium" can include any medium that can store or transmit information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical discs, hard disks, fiber optic media, radio frequency (RF) links, etc. The code segment can be downloaded via a computer network such as the Internet, an intranet, etc.

[0115] It should also be noted that in the exemplary embodiments mentioned in the present invention, some methods or systems are described based on a series of steps or devices. However, the present invention is not limited to the order of the above steps, that is, the steps can be executed in the order mentioned in the embodiments, or different from the order in the embodiments, or several steps can be executed simultaneously.

[0116] As described above, the above are only specific embodiments of the present invention. Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the above-described systems, modules, and units can refer to the corresponding processes in the foregoing method embodiments and will not be repeated herein. It should be understood that the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should be covered within the protection scope of the present invention.

Claims

1. A method for setting the amount of white ink based on the inverse gray value, characterized in that, The method includes: Obtaining the values of the gray levels of each pixel point after grayscale processing of the color image and then performing inverse color processing, denoted as inverse color gray level values; Obtaining the initial mapping relationship between the inverse color gray level values of each pixel point and the white ink amount value; Selecting n inverse color gray level values from the inverse color gray level values as sample inverse color gray level values, where n≥1 and n is an integer; Comparing the sample inverse color gray level values with a preset gray level threshold to obtain a comparison result; Adjusting the initial mapping relationship according to the comparison result to obtain an actual mapping relationship; Obtaining the white ink amount value for underlaying each pixel point of the color image before printing the color image according to the inverse color gray level values of each pixel point and the actual mapping relationship.

2. The method for setting the amount of white ink based on the inverted gray value according to claim 1, wherein The obtaining of the initial mapping relationship between the inverse color gray level values of each pixel point and the white ink amount value includes: Obtaining the initial mapping relationship according to the following formula: W = H, where W is the white ink amount value and H is the inverse color gray level value.

3. The method for setting the white ink amount based on the inverse color grayscale value according to claim 1, wherein, The adjusting of the initial mapping relationship according to the comparison result to obtain the actual mapping relationship includes: Automatically adjusting the initial mapping relationship according to the comparison result by calling an adjustment program in the memory to obtain the actual mapping relationship.

4. The method for setting the white ink amount based on the inverse gray value according to claim 3, wherein The adjustment program includes: when the inverse color gray level values of most pixel points in the color image are less than the preset gray level threshold, the white ink amount values corresponding to all the inverse color gray level values less than the preset gray level threshold should be correspondingly reduced, and the white ink amount values corresponding to all the inverse color gray level values greater than the preset gray level threshold should be correspondingly increased.

5. The method for setting the white ink amount based on the inverse color gray value according to claim 1, characterized in that When n = 1, the sample inverse color gray level value is the inverse color gray level value corresponding to the most pixel points.

6. The method for setting the amount of white ink based on the inverse color gray value according to claim 1, wherein, When n>1, the selecting of n inverse color gray level values from the inverse color gray level values as sample inverse color gray level values includes: Sorting all the inverse color gray level values in descending order according to the number of corresponding pixel points to obtain an inverse color gray level value sequence list; Selecting n inverse color gray level values from the inverse color gray level value sequence list in descending order, and the n inverse color gray level values are the sample inverse color gray level values.

7. The method for setting the amount of white ink based on the inverted gray value according to any one of claims 1-7, characterized in that, After obtaining the white ink amount value for underlaying each pixel point of the color image before printing the color image according to the inverse color gray level values of each pixel point and the actual mapping relationship, it further includes: Performing white ink underlay printing according to the white ink amount value, and then performing color printing according to the color ink amount.

8. An apparatus for setting the amount of white ink based on the inverted gray value, characterized in that, The device includes: An inverse color gray level value obtaining module, configured to obtain the values of the gray levels of each pixel point after grayscale processing of the color image and then perform inverse color processing, denoted as inverse color gray level values; An initial mapping relationship obtaining module, always obtaining the initial mapping relationship between the inverse color gray level values of each pixel point and the white ink amount value; A selecting module, configured to select n inverse color gray level values from the inverse color gray level values as sample inverse color gray level values, where n≥1 and n is an integer; A comparing module, configured to compare the sample inverse color gray level values with a preset gray level threshold to obtain a comparison result; An actual mapping relationship obtaining module, configured to adjust the initial mapping relationship according to the comparison result to obtain an actual mapping relationship; The white ink amount setting module is used to obtain the white ink amount value for underlaying each pixel of the color image before printing the color image according to the inverted gray value of each pixel and the actual mapping relationship.

9. An equipment for setting the amount of white ink based on the inverted gray value, characterized in that It includes: At least one processor, at least one memory, and computer program instructions stored in the memory, which implement the method according to any one of claims 1-7 when the computer program instructions are executed by the processor.

10. A medium on which computer program instructions are stored, characterized in that, When the computer program instructions are executed by the processor, the method according to any one of claims 1-7 is implemented.

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