Image correction method, image forming device and storage medium

Abstract

The embodiment of the present application provides a portrait correction method, an image forming device and a storage medium, the method comprising obtaining the first end color density value and / or the second end color density value of the correction reference image along the direction to be corrected; performing difference calculation between the first end color density value and / or the second end color density value and the target color density value to obtain the first end color density difference and / or the second end color density difference; if the first end color density difference and / or the second end color density difference is greater than or equal to a preset difference threshold, then performing uniformity correction on the image to be corrected. By adopting the scheme provided in the embodiment of the present application, uniformity correction can be performed on an image forming device with poor uniformity, so that the image printed by the image forming device has a better uniformity effect. In addition, the correction scheme provided in the embodiment of the present application can avoid multiple measurements or corrections affecting printing efficiency, saving measurement time and cost.

Description

Technical Field

[0001] The present application relates to the field of image forming technology, and in particular to an image correction method, an image forming device and a storage medium. Background Art

[0002] The image forming apparatus is a device that forms an image on a recording medium by the imaging principle, such as a printer, a copier, a fax machine, a multifunctional image making and copying apparatus, an electrostatic printing apparatus, and any other similar apparatus.

[0003] The photosensitive component is one of the most important parts in the image forming process of the image forming device. Common photosensitive components include a photosensitive drum, the surface of which is coated with photosensitive materials. When the laser scanning unit (LSU) irradiates the surface of the photosensitive drum, the resistance of the irradiated part becomes smaller and the charge disappears; while the part not irradiated by the laser scanning unit still retains the charge. Finally, an electrostatic latent image composed of charges is formed on the surface of the photosensitive drum. When the charged photosensitive drum surface passes through the developing component, the developing roller sends the developer such as toner used to form a visible image to the electrostatic latent image on the surface of the photosensitive drum in combination with the action of forces such as electric field forces, so that the above-mentioned electrostatic latent image is visualized.

[0004] However, after long-term use, the image forming device may have uneven imaging due to aging of the photosensitive drum. For example, the left and right images are often lighter, while the middle image is darker, that is, the image has poor uniformity in the horizontal direction. Of course, there may also be poor uniformity in other directions, such as the vertical direction. Summary of the invention

[0005] The embodiment of the present application provides a method for image correction, an image forming device and a storage medium, so as to solve the problem of poor imaging uniformity in the prior art. Of course, there may also be a problem of poor uniformity in other directions, such as the vertical direction.

[0006] In a first aspect, an embodiment of the present application provides a method for image correction, comprising:

[0007] Acquire a first end color density value and / or a second end color density value of a correction reference image along a direction to be corrected;

[0008] Calculate the difference between the first end color density value and / or the second end color density value and the target color density value to obtain a first end color density difference value and / or a second end color density difference value;

[0009] If the first end color density difference and / or the second end color density difference is greater than or equal to a preset difference threshold, uniformity correction is performed on the image to be corrected.

[0010] Preferably, the uniformity correction of the image to be corrected includes:

[0011] Taking the reference axis of the image to be corrected as the standard position, interpolating and fitting to calculate the compensated color density value of the image to be corrected, wherein the reference axis is perpendicular to the direction to be corrected;

[0012] The original dot matrix image of the image to be corrected is merged with the compensated dot matrix image corresponding to the compensated color density value to obtain a corrected image.

[0013] Preferably, before fusing the original dot matrix image of the image to be corrected with the compensated dot matrix image corresponding to the compensated color density value to obtain the corrected image, the method further includes:

[0014] Converting the compensated color density value into a corresponding pixel grayscale value;

[0015] Convert the pixel grayscale value into corresponding raster dot matrix data;

[0016] According to the black dot distribution characteristics of the raster dot matrix data, it is determined whether it is necessary to perform uniformity correction processing on the image to be corrected.

[0017] Preferably, converting the compensated color density value into a corresponding pixel grayscale value comprises:

[0018] According to the mapping table, the compensated color density value is mapped to a corresponding pixel grayscale value.

[0019] Preferably, converting the pixel grayscale value into corresponding raster dot matrix data comprises:

[0020] According to the halftone matrix table, the pixel grayscale value is converted into corresponding raster dot matrix data.

[0021] Preferably, converting the pixel grayscale value into corresponding raster dot matrix data according to the halftone matrix table includes:

[0022] According to the halftone matrix table of each color channel, the pixel grayscale value is converted into corresponding raster dot matrix data through the same binary rasterization method.

[0023] Preferably, the target color density value is a preset color density value matching the correction reference image; or,

[0024] The target color density value is an average of the first end color density value and the second end color density value.

[0025] Preferably, the correction reference image includes a first color block group and a second color block group which are symmetrically arranged relative to a reference axis of the correction reference image, the pixel values ​​of the symmetrical color blocks in the first color block group and the second color block group are the same, and the reference axis is perpendicular to the direction to be corrected.

[0026] Preferably, the first color block group and the second color block group respectively include two or more color blocks, and the two or more color blocks have different pixel values.

[0027] Preferably, before acquiring the first end color density value and / or the second end color density value of the correction reference image along the direction to be corrected, the method further comprises:

[0028] Print the calibration reference image.

[0029] Preferably, the direction to be corrected is the horizontal direction and / or the vertical direction of the printed page.

[0030] In a second aspect, an embodiment of the present application provides an image forming device, including:

[0031] processor;

[0032] Memory;

[0033] A computer program is stored in the memory, and when the computer program is executed, the image forming apparatus executes the method according to any one of the first aspects.

[0034] In a third aspect, an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium includes a stored program, wherein when the program is running, the device where the computer-readable storage medium is located is controlled to execute any method described in the first aspect.

[0035] By adopting the scheme provided in the embodiment of the present application, uniformity correction can be performed on an image forming device with poor uniformity, so that the image printed by the image forming device has a better uniformity effect. In addition, the correction scheme provided in the embodiment of the present application can avoid multiple measurements or corrections affecting the printing efficiency, saving measurement time and cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0037] Figure 1 A schematic diagram of an application scenario provided for an embodiment of the present application;

[0038] Figure 2A A schematic diagram of an image to be corrected provided in an embodiment of the present application;

[0039] Figure 2B A schematic diagram of a color density curve provided in an embodiment of the present application;

[0040] Figure 3 A schematic diagram of a method for image correction provided in an embodiment of the present application;

[0041] Figure 4 A schematic diagram of a correction reference image provided in an embodiment of the present application;

[0042] Figure 5A Another color density curve schematic diagram provided in an embodiment of the present application;

[0043] Figure 5B An image after uniformity correction provided in an embodiment of the present application;

[0044] Figure 5C Another color density curve schematic diagram provided in an embodiment of the present application;

[0045] Fig. 6A A schematic diagram of an image to be corrected provided in an embodiment of the present application;

[0046] Figure 6B Another color density curve schematic diagram provided in an embodiment of the present application;

[0047] Figure 6C For Fig. 6A Schematic diagram of the image after uniformity correction;

[0048] Figure 7 A schematic diagram of the structure of an image processing device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0049] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0050] It should be clear that the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0051] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0052] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0053] See also Figure 1 , is a schematic diagram of an application scenario provided by an embodiment of the present application. Figure 1 An image forming device 100 is shown in FIG. 1 , and the image correction method provided in the embodiment of the present application can be applied to the image forming device 100. It can be understood that Figure 1 The above is only an exemplary description, and the present embodiment does not limit the specific form of the image forming apparatus 100. For example, the image forming apparatus 100 includes but is not limited to a printer, a copier, a fax machine, a scanner, and a multifunctional peripheral that performs the above functions in a single device.

[0054] In actual application, after long-term use, the image forming device may have uneven imaging due to aging of the photosensitive drum and other reasons.

[0055] See also Figure 2A , is a schematic diagram of an image to be corrected provided in an embodiment of the present application. Figure 2A As shown, the left and right images of the image to be corrected are lighter, while the middle image is darker.

[0056] See also Figure 2B , is a schematic diagram of a color density curve provided in an embodiment of the present application. The color density curve is Figure 2A The color density curve of the image shown is used to reflect the color density change of the image in the horizontal direction. From the color density curve, it can be seen that the color density values ​​are higher on the left and right sides of the image, and the color density value in the middle is lower.

[0057] Therefore, from Figure 2A and Figure 2B It can be seen that the image to be corrected has poor uniformity in the horizontal direction.

[0058] It is understandable that, in addition to the horizontal direction, there may also be a problem of poor uniformity in other directions, such as the vertical direction.

[0059] Based on this, the embodiments of the present application provide a method for image correction, an image forming device and a storage medium, so as to solve the problem of poor imaging uniformity in the prior art.

[0060] See also Figure 3, is a schematic diagram of a method for image correction provided in an embodiment of the present application. The method can be applied to Figure 1 The image forming device shown in Figure 3 As shown, it mainly includes the following steps.

[0061] Step S301: Acquire a first-end color density value and / or a second-end color density value of a correction reference image along a direction to be corrected.

[0062] The direction to be corrected involved in the embodiment of the present application is the direction in which uniformity correction is required in the printed page. For example, the direction to be corrected can be the horizontal direction or the vertical direction of the printed page, and of course, it can also be other directions of the printed page, which is not specifically limited in the embodiment of the present application.

[0063] In a specific implementation, a correction reference image may be printed by the image forming device to be corrected, so as to correct the image forming device to be corrected based on the correction reference image.

[0064] In some possible implementations, the correction reference image may be a halftone image, wherein halftone refers to a picture tone whose tone value is expressed by dot size or density. The corresponding to halftone is continuous tone. Continuous tone images usually refer to an image whose tone change from light to dark or from shallow to dark is composed of the density of imaging material particles per unit area, and whose depth and lightness are infinitely variable, such as photo negatives, photos, and various drawings; while halftones usually refer to a specially processed printed product whose tone change from shallow to dark or from shallow to dark is expressed by dot size. Since the dots are discretely distributed at a certain distance in space, and since the number of screening levels is always limited, the image level change cannot be infinitely variable like a continuous tone image, so it is called a halftone image.

[0065] Color density can reflect the depth of the image. If the color density values ​​at both ends of the direction to be corrected differ greatly from the target color density values, it means that the uniformity of the direction to be corrected is poor, and the image forming device needs to be corrected for uniformity in the direction to be corrected. On the contrary, if the color density values ​​at both ends of the direction to be corrected differ slightly from the target color density values, it means that the uniformity of the direction to be corrected is good, and the image forming device does not need to be corrected for uniformity in the direction to be corrected. Therefore, the embodiment of the present application needs to obtain the color density values ​​at both ends of the direction to be corrected in the correction reference image. For the sake of convenience, the color density values ​​at both ends of the direction to be corrected in the embodiment of the present application are respectively referred to as the first end color density value and the second end color density value.

[0066] It should be noted that in some possible implementations, the first end color density value and the second end color density value may respectively include a set of data, for example, including N first end color density values ​​and N second end color density values, where N≥2.

[0067] For example, when the direction to be corrected is the horizontal direction, the first end color density value and the second end color density value are respectively the left end color density value and the right end color density value of the corrected reference image. In a specific implementation, the left end color density value and the right end color density value may respectively contain a set of data, that is, N left end color density values ​​and N right end color density values. The i-th left end color density value is represented as Density_Left[i]; the i-th right end color density value is represented as Density_Right[i].

[0068] In some possible implementations, the correction reference image includes a first color block group and a second color block group that are symmetrically arranged relative to a reference axis of the correction reference image, the pixel values ​​of the symmetrical color blocks in the first color block group and the second color block group are the same, and the reference axis is perpendicular to the direction to be corrected.

[0069] As shown above, the first end color density value and the second end color density value may respectively include a set of data, that is, N first end color density values ​​and N second end color density values, respectively, N ≥ 2. Correspondingly, the first color block group and the second color block group include N color blocks, respectively, so that N first end color density values ​​are obtained according to the N color blocks in the first color block group; and N second end color density values ​​are obtained according to the N color blocks in the second color block group. In some possible implementations, the pixel values ​​of the N color blocks are different. For example, the pixel values ​​of the N color blocks vary uniformly between 0-255. Of course, those skilled in the art can also use other methods to set the pixel values ​​of the N color blocks, and the embodiments of the present application do not impose specific restrictions on this.

[0070] See also Figure 4 , is a schematic diagram of a correction reference image provided in an embodiment of the present application. Figure 4 The correction direction corresponding to the correction reference image shown is the horizontal direction. The correction reference image includes two color block groups, namely a first color block group and a second color block group. The first color block group and the second color block group are arranged symmetrically on the left and right.

[0071] Specifically, the first color block group and the second color block group include 9 color blocks respectively, and the RGB values ​​of the 9 color blocks are (0, 0, 0) (32, 32, 32) (64, 64, 64) (96, 96, 96) (128, 128, 128) (160, 160, 160) (192, 192, 192) (224, 224, 224) (255, 255, 255) from top to bottom.

[0072] In the embodiment of the present application, the first color block group and the second color block group are symmetrically arranged, which means that the positions of the color blocks in the first color block group and the second color block group are symmetrically arranged, and the RGB values ​​of the symmetrical color blocks are the same. Figure 4 In the correction reference image shown, the RGB values ​​of the two left and right color blocks in the first row are both (0, 0, 0), the RGB values ​​of the two left and right color blocks in the second row are both (32, 32, 32), etc., which will not be elaborated in this embodiment of the present application.

[0073] Specifically, according to Figure 4 The left end color density value and the right end color density value obtained by the correction reference image shown are shown in Table 1.

[0074] Table 1:

[0075]

[0076] The color density value of the left end of the color block in the first row is 1.08, and the color density value of the right end is 1.11; the color density value of the left end of the color block in the second row is 0.84, and the color density value of the right end is 0.96, etc. No further details will be given here.

[0077] It should be pointed out that Figure 4 The calibration reference image shown is only a possible implementation method and should not be used as a limitation to the protection scope of the present application. For example, those skilled in the art can set more than two color blocks (for example, 3 or 4) in each row according to actual needs, and only take the color density values ​​of the color blocks at the left and right ends when making a judgment on whether calibration is needed; of course, the color density values ​​of the two or more color blocks can also be used to make a judgment on whether calibration is needed, and the present application embodiment does not make specific limitations on this.

[0078] Step S302: performing difference calculation between the first end color density value and / or the second end color density value and the target color density value to obtain a first end color density difference value and / or a second end color density difference value.

[0079] In a possible implementation, the target color density value may be a preset color density value that matches the calibration reference image; or, the target color density value may be the average of the first end color density value and the second end color density value. In a specific implementation, an image forming device with normal calibration and uniformity may be used to collect the color density values ​​of each color block in the calibration reference image, obtain the color density value of each color block, and calculate the target color density value by the average of the first end color density value and the second end color density value. The embodiment of the present application does not impose any specific limitation on this.

[0080] As shown above, the first end color density value and the second end color density value may respectively include a set of data, namely, N first end color density values ​​and N second end color density values, N≥2. Correspondingly, the target color density value also includes a set of data, namely, N target color density values.

[0081] See Table 2 for a method for Figure 4 The target color density value corresponding to the reference image shown in the correction is shown in Table 2. The target color density value contains 9 data, corresponding to Figure 4 Each row of color blocks in the image, that is, each row of color blocks corresponds to a target color density value. For example, the target color density value corresponding to the first row of color blocks is 1.12, the target color density value corresponding to the second row of color blocks is 0.98, and so on.

[0082] Table 2:

[0083]

[0084] For ease of explanation, the i-th target color density value is recorded as Density_Center[i]. In a specific implementation, the N first-end color density values ​​and / or the N second-end color density values ​​are respectively subtracted from the N target color density values ​​to obtain N first-end color density differences and / or N second-end color density differences, where N≥2.

[0085] If the direction to be corrected is horizontal, the left end color density value and / or the right end color density value are respectively calculated with the target color density value to obtain the left end color density difference value and / or the right end color density difference value. The specific calculation formula is as follows:

[0086] Formula 1: DeltaDensity_CL[i]=Density_Center[i]-Density_Left[i]

[0087] Formula 2: DeltaDensity_CR[i]=Density_Center[i]-Density_Right[i]

[0088] Among them, DeltaDensity_CL[i] represents the i-th left-end color density value, and DeltaDensity_CR[i] represents the i-th right-end color density value.

[0089] In a possible implementation, the left end color density value and the right end color density value shown in Table 1 are respectively calculated with the target color density value shown in Table 2 to obtain the left end color density difference and the right end color density difference, as shown in Table 3.

[0090] Table 3:

[0091]

[0092] The color density difference of the left end of the color block in the first row is 0.04, and the color density difference of the right end is 0.01; the color density difference of the left end of the color block in the second row is 0.14, and the color density difference of the right end is 0.02, etc. No further description is given here.

[0093] Step S303: If the first-end color density difference and / or the second-end color density difference is greater than or equal to a preset difference threshold, uniformity correction is performed on the image to be corrected.

[0094] The image to be corrected involved in the embodiment of the present application can be understood as an image printed by an image forming device to be corrected.

[0095] In a specific implementation, the embodiment of the present application sets a difference threshold value so as to compare the first end color density difference value and / or the second end color density difference value obtained in step S302 with the difference threshold value respectively to determine whether uniformity correction is required. If the first end color density difference value and / or the second end color density difference value is greater than or equal to the preset difference threshold value, it means that the uniformity of the correction reference image is poor, that is, the uniformity of the corresponding image forming device is poor, and the image forming device needs to be corrected for uniformity; on the contrary, if the first end color density difference value and / or the second end color density difference value is less than the preset difference threshold value, it means that the uniformity of the correction reference image is good, that is, the uniformity of the corresponding image forming device is good, and the image forming device does not need to be corrected for uniformity.

[0096] In a possible implementation, if the color density difference at the first end or the color density difference at the second end is greater than or equal to a preset difference threshold, uniformity correction is performed on the image to be corrected. In other words, uniformity correction is performed as long as the color density difference at one end is greater than or equal to the preset difference threshold.

[0097] Among them, those skilled in the art can set the difference threshold of the corresponding size according to actual needs, and the embodiments of the present application will not be described in detail.

[0098] In some possible implementations, uniformity correction is performed on the image to be corrected, specifically including: taking the reference axis of the image to be corrected as the standard position, interpolating and fitting to calculate the compensated color density value of the image to be corrected, the reference axis being perpendicular to the direction to be corrected, preferably, the reference axis can be the perpendicular bisector of the page width, and the page width can be understood as the page direction corresponding to the direction to be corrected; fusing the original dot matrix image of the image to be corrected with the compensated dot matrix image corresponding to the compensated color density value to obtain a corrected image.

[0099] See Table 4, which is an interpolation fitting calculation of the compensation color density value within the page width provided in the embodiment of the present application. Figure 4 In the illustrated embodiment, the page width corresponds to the horizontal direction.

[0100] Table 4:

[0101] LeftN Left… Left3 Left2 Left1 Left0 Center Right0 Right1 Right2 Right3 Right… RightN BN B... B3 B2 B1 B0 Target A0 A1 A2 A3 A... AN

[0102] Among them, AN is the compensation color density value corresponding to Density_Right, BN is the compensation color density value corresponding to Density_Left, and Target is the compensation color density value corresponding to Density_Center.

[0103] See also Figure 5A , is another color density curve schematic diagram provided in the embodiment of the present application. Figure 5A The color density curve of the image to be corrected and the compensation color density curve are shown in FIG. Figure 2B The color density curve shown, the supplementary color density curve is a color density curve corresponding to the compensated dot matrix image.

[0104] Will Figure 5A The compensation dot matrix image corresponding to the compensation color density curve shown is Figure 2A After the original dot matrix images shown are fused, an image after uniformity correction is obtained.

[0105] See also Figure 5B , is an image after uniformity correction provided in an embodiment of the present application. The image after uniformity correction is Figure 2A The image shown is the image after uniformity correction, as shown in Figure 5B As shown, the image after uniformity correction has a better uniformity effect in the depth of the image in the horizontal direction.

[0106] See also Figure 5C , is another color density curve schematic diagram provided in an embodiment of the present application. Figure 5C and Figure 5A The difference is that the uniformity-corrected color density curve is added. The uniformity-corrected color density curve is Figure 5B The color density curve of the image shown is used to reflect the color density change of the image after uniformity correction in the horizontal direction. It can be seen from the color density curve after uniformity correction that the uniformity effect of the color density value along the horizontal direction is good. In a possible implementation, in order to further improve the accuracy of image correction, after obtaining the compensated color density value, it can be further confirmed whether uniformity correction is required based on the compensated color density value.

[0107] Specifically, before uniformity correction is performed, the compensation color density value is converted into a corresponding pixel grayscale value. Specifically, the compensation color density value can be converted into a corresponding pixel grayscale value by a table lookup mapping method. Then, the pixel grayscale value is converted into the corresponding raster dot matrix data. Specifically, the pixel grayscale value can be converted into the corresponding raster dot matrix data by the same binary rasterization method according to the halftone matrix table of each color channel. Finally, according to the black dot distribution characteristics of the raster dot matrix data, it is determined whether the image to be corrected needs to be subjected to uniformity correction processing. In this way, it is verified again whether it is necessary to perform uniformity correction. The black dot distribution characteristics mainly refer to the presentation effect of different carbon powders and different imaging systems on 0 / 1 dot matrix images. This effect will have a certain tolerance, that is, even if there is a difference within a certain range, the human eye cannot distinguish it; beyond this range, the human eye can distinguish it, and correction is required in this case.

[0108] If it is determined through the above method that uniformity correction is necessary, uniformity correction is performed on the image to be corrected; otherwise, uniformity correction is not performed.

[0109] See also Fig. 6A , is a schematic diagram of an image to be corrected provided in an embodiment of the present application. Fig. 6A As shown, the uniformity of the image to be corrected in the page width direction is poor, so it is necessary to perform uniformity correction on the image in the page width direction.

[0110] See also Figure 6B , is another color density curve schematic diagram provided in an embodiment of the present application. The horizontal axis represents the RGB data corresponding to the correction reference image, and the vertical axis represents the color density value. Curve DL represents the left color density curve obtained by detecting the correction reference image; curve DR represents the right color density curve obtained by detecting the correction reference image; curve Refer represents the expected standard color density curve; curve Curve represents the compensated color density curve calculated according to the correction reference image.

[0111] See also Figure 6C , for Fig. 6A Schematic diagram of the image after uniformity correction. Figure 6B The compensated color density curves shown are Fig. 6A The images shown are corrected for uniformity. Figure 6C As shown, after uniformity correction, the image has better uniformity in depth in the page width direction.

[0112] By adopting the scheme provided in the embodiment of the present application, uniformity correction can be performed on an image forming device with poor uniformity, so that the image printed by the image forming device has a better uniformity effect. In addition, the correction scheme provided in the embodiment of the present application can avoid multiple measurements or corrections affecting the printing efficiency, saving measurement time and cost.

[0113] Corresponding to the above method embodiments, the present application also provides an image processing device.

[0114] See also Figure 7 , is a schematic diagram of the structure of an image processing device provided in an embodiment of the present application, and the image processing device 700 may include: a processor 701, a memory 702, and a communication unit 703. These components communicate through one or more buses. Those skilled in the art can understand that the structure of the server shown in the figure does not constitute a limitation on the embodiment of the present invention. It can be a bus structure or a star structure, and can also include more or fewer components than shown in the figure, or combine certain components, or arrange the components differently.

[0115] The communication unit 703 is used to establish a communication channel so that the storage device can communicate with other devices, receive user data sent by other devices or send user data to other devices.

[0116] The processor 701 is the control center of the storage device, and uses various interfaces and lines to connect various parts of the entire system, and executes various functions of the system and / or processes data by running or executing software programs and / or modules stored in the memory 702, and calling data stored in the memory. The processor can be composed of an integrated circuit (IC), for example, a single packaged IC, or a plurality of packaged ICs with the same or different functions.

[0117] The memory 702 is used to store the execution instructions of the processor 701. The memory 702 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk.

[0118] When the execution instructions in the memory 702 are executed by the processor 701 , the image processing device 700 can execute part or all of the steps on the image processing device side in the above method embodiment.

[0119] In a specific implementation, the present application further provides a computer-readable storage medium, wherein the computer-readable storage medium may store a program, and when the program is executed, the program may include some or all of the steps in each embodiment provided in the present application. The above-mentioned storage medium may be a disk, an optical disk, a read-only memory (ROM) or a random access memory (RAM).

[0120] In a specific implementation, an embodiment of the present application further provides a computer program product, which includes executable instructions. When the executable instructions are executed on a computer, the computer executes some or all of the steps in the above method embodiment.

[0121] In the embodiments of the present application, "at least one" refers to one or more, and "plurality" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. Among them, A and B can be singular or plural. The character " / " generally indicates that the previous and subsequent associated objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b and c can be represented by: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0122] Those of ordinary skill in the art will appreciate that the various units and algorithm steps described in the embodiments disclosed herein can be implemented in a combination of electronic hardware, computer software, and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0123] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0124] The above is only a specific implementation of the present application. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. The protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for image correction, characterized in that: include: Acquire a first end color density value and / or a second end color density value of a correction reference image along a direction to be corrected; Calculate the difference between the first end color density value and / or the second end color density value and the target color density value to obtain a first end color density difference value and / or a second end color density difference value; If the color density difference at the first end and / or the color density difference at the second end is greater than or equal to a preset difference threshold, performing uniformity correction on the image to be corrected; The uniformity correction of the image to be corrected comprises: Taking the reference axis of the image to be corrected as the standard position, interpolating and fitting to calculate the compensated color density value of the image to be corrected, wherein the reference axis is perpendicular to the direction to be corrected; Converting the compensated color density value into a corresponding pixel grayscale value; Convert the pixel grayscale value into corresponding raster dot matrix data; Determining whether it is necessary to perform uniformity correction processing on the image to be corrected according to the black dot distribution characteristics of the raster dot matrix data; If it is determined that the image to be corrected needs to be corrected for uniformity, the original dot matrix image of the image to be corrected is merged with the compensated dot matrix image corresponding to the compensated color density value to obtain a corrected image; When the first end color density value or the second end color density value of the correction reference image is obtained along the direction to be corrected, the target color density value is a preset color density value that matches the correction reference image; when the first end color density value and the second end color density value of the correction reference image are obtained along the direction to be corrected, the target color density value is a preset color density value that matches the correction reference image, or the average of the first end color density value and the second end color density value.

2. The method according to claim 1, characterized in that: The converting the compensated color density value into a corresponding pixel grayscale value comprises: According to the mapping table, the compensated color density value is mapped to a corresponding pixel grayscale value.

3. The method according to claim 1, characterized in that The step of converting the pixel grayscale value into corresponding raster dot matrix data comprises: According to the halftone matrix table, the pixel grayscale value is converted into corresponding raster dot matrix data.

4. The method according to claim 3, characterized in that The step of converting the pixel grayscale value into corresponding raster dot matrix data according to the halftone matrix table includes: According to the halftone matrix table of each color channel, the pixel grayscale value is converted into corresponding raster dot matrix data through the same binary rasterization method.

5. The method according to claim 1, characterized in that The correction reference image includes a first color block group and a second color block group symmetrically arranged relative to a reference axis of the correction reference image, the pixel values ​​of the mutually symmetrical color blocks in the first color block group and the second color block group are the same, and the reference axis is perpendicular to the direction to be corrected.

6. The method according to claim 5, characterized in that The first color block group and the second color block group respectively include two or more color blocks, and the two or more color blocks have different pixel values.

7. The method according to claim 1, characterized in that Before acquiring the first end color density value and / or the second end color density value of the correction reference image along the direction to be corrected, the method further includes: Print the calibration reference image.

8. The method according to claim 1, characterized in that The direction to be corrected is the horizontal direction and / or the vertical direction of the printed page.

9. An image forming device, characterized in that: include: processor; Memory; The memory stores a computer program, and when the computer program is executed, the image forming apparatus executes the method according to any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute the method according to any one of claims 1 to 8.

Images