Frequency modulation net generation method, device and equipment in net hanging plate making

Abstract

The invention provides a frequency modulation network generation method, device and equipment in network plate making. The method comprises the following steps: acquiring a target threshold matrix to be assigned, a neighboring point aggregation operator matrix and an inter-point diffusion operator matrix; obtaining an intermediate matrix according to the adjacent point aggregation operator matrix and the inter-point diffusion operator matrix; assigning a value to one item in the target threshold matrix according to the value of each item of data in the intermediate matrix; iteration is carried out on the adjacent point aggregation operator matrix and the inter-point diffusion operator matrix until each item in the target threshold matrix is assigned, and the assigned target threshold matrix is obtained; and generating a frequency modulation network according to the assigned target threshold matrix. According to the scheme, the frequency modulation halftone conversion efficiency of the digital image can be improved, and the problem of low efficiency caused by a traditional error diffusion algorithm is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of image hard copy reproduction, in particular to a method, device and equipment for generating frequency modulation screen in screen plate making. Background Art

[0002] The hard copy reproduction of images mainly involves the screen plate-making technology of printers and high-end printing plate-making equipment. The screen technology used for hard copy reproduction of images is also called digital image halftone technology. One of the more common types of digital image halftone technology is frequency modulation screening. It achieves grayscale reproduction of the original image by controlling the number of dyeing points per unit area. Since the dyeing points in the frequency modulation halftone image are distributed in a non-clustered form, different original gray levels will correspond to different average distances between dyeing points. From the perspective of digital image processing, the frequency of the image is changing, which is the origin of the term frequency modulation screening.

[0003] In the traditional FM screening method, the error diffusion method is the most commonly used method. However, this method requires complex error diffusion processing for each pixel of the original image in the screening process, which involves multiple mathematical operations and complex table lookup operations. In actual applications, the number of pixels processed in the original image is tens of thousands or even more. Therefore, the FM screening (digital image FM halftone conversion) implemented by the traditional error diffusion calculation method has a serious lag in the actual output efficiency, greatly reducing the output speed of the equipment, thereby affecting the industrial application of efficient batch output, limiting its wide application space, and needs further improvement and perfection. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method, device and equipment for generating frequency modulated screen in screen plate making, which can improve the efficiency of frequency modulated halftone conversion of digital images and solve the problem of low efficiency caused by traditional error diffusion algorithm.

[0005] In order to solve the above technical problems, the technical solution of the present invention is as follows:

[0006] A method for generating a frequency modulation screen in screen plate making, comprising:

[0007] Obtain the target threshold matrix to be assigned, the adjacent point aggregation operator matrix and the point diffusion operator matrix;

[0008] Obtaining an intermediate matrix according to the adjacent point aggregation operator matrix and the inter-point diffusion operator matrix;

[0009] Assign a value to an item in the target threshold matrix according to the value of each item of data in the intermediate matrix;

[0010] Iterating the adjacent point aggregation operator matrix and the inter-point diffusion operator matrix until each item in the target threshold matrix is ​​assigned a value, thereby obtaining a target threshold matrix after the assignment; wherein each item in the target threshold matrix after the assignment represents a gray level for frequency modulation halftone conversion of a digital image in screen plate making;

[0011] The frequency modulation network is generated according to the assigned target threshold matrix.

[0012] Optionally, obtain the target threshold matrix to be assigned, the adjacent point aggregation operator matrix, and the point diffusion operator matrix, including:

[0013] Obtain a target threshold matrix of size W*W, a neighboring point aggregation operator matrix with randomly initialized values, and an inter-point diffusion operator matrix with initialized values ​​of preset values, where W is a positive integer.

[0014] Optionally, an intermediate matrix is ​​obtained according to the adjacent point aggregation operator matrix and the point diffusion operator matrix, including:

[0015] Perform matrix convolution on the adjacent point aggregation operator matrix and the point diffusion operator matrix to obtain an intermediate matrix; the intermediate matrix is ​​equal to the target threshold matrix in size.

[0016] Optionally, assigning a value to an item in the target threshold matrix according to the value of each item of data in the intermediate matrix includes:

[0017] According to the value of each item of data in the intermediate matrix, determining the item of data with the largest value in the intermediate matrix;

[0018] According to the index coordinate value of the data item with the largest value, an item corresponding to the index coordinate value in the target threshold matrix is ​​assigned a value.

[0019] Optionally, the adjacent point aggregation operator matrix and the point diffusion operator matrix are iterated until each item in the target threshold matrix is ​​assigned a value, and the assigned target threshold matrix is ​​obtained, including:

[0020] Iterating the adjacent point aggregation operator matrix and the point diffusion operator matrix to obtain an iterated adjacent point aggregation operator matrix and point diffusion operator matrix;

[0021] Obtaining a new intermediate matrix according to the iterated adjacent point aggregation operator matrix and the inter-point diffusion operator matrix;

[0022] Assign a value to an item in the target threshold matrix according to the value of each item of data in the new intermediate matrix;

[0023] The adjacent point aggregation operator matrix and the inter-point diffusion operator matrix are repeatedly iterated until each item in the target threshold matrix is ​​assigned a value, thereby obtaining a target threshold matrix after the assignment.

[0024] Optionally, iterating the adjacent point aggregation operator matrix and the point diffusion operator matrix to obtain the iterated adjacent point aggregation operator matrix and the point diffusion operator matrix includes:

[0025] Multiplying the adjacent point aggregation operator matrix by a preset function to obtain an iterated adjacent point aggregation operator matrix;

[0026] A preset value is subtracted from the inter-point diffusion operator matrix to obtain an iterated inter-point diffusion operator matrix.

[0027] Optionally, assigning a value to an item in the target threshold matrix according to the value of each item of data in the new intermediate matrix includes:

[0028] According to the value of each item of data in the new intermediate matrix, determining the item of data with the largest value in the new intermediate matrix;

[0029] According to the index coordinate value of the data item with the largest value, a value is assigned to an item corresponding to the index coordinate value in the target threshold matrix; each time the intermediate matrix is ​​updated, the value assigned in the target threshold matrix is ​​increased by one.

[0030] The present invention also provides a frequency modulation screen generating device in screen plate making, comprising:

[0031] An acquisition module is used to obtain a target threshold matrix to be assigned, a neighboring point aggregation operator matrix, and an inter-point diffusion operator matrix;

[0032] A processing module is used to obtain an intermediate matrix according to the adjacent point aggregation operator matrix and the point diffusion operator matrix; assign a value to an item in the target threshold matrix according to the value of each item of data in the intermediate matrix; iterate the adjacent point aggregation operator matrix and the point diffusion operator matrix until each item in the target threshold matrix is ​​assigned a value, thereby obtaining the assigned target threshold matrix; wherein each item in the assigned target threshold matrix represents a grayscale level for frequency modulation halftone conversion of a digital image in screen platemaking; and generate the frequency modulation screen according to the assigned target threshold matrix.

[0033] The present invention also provides a computing device, comprising: a processor and a memory storing a computer program, wherein when the computer program is run by the processor, the method as described above is executed.

[0034] The present invention also provides a computer-readable storage medium storing instructions, which, when executed on a computer, enable the computer to execute the above method.

[0035] The above solution of the present invention includes at least the following beneficial effects:

[0036] The above scheme of the present invention obtains the target threshold matrix to be assigned, the adjacent point aggregation operator matrix and the inter-point diffusion operator matrix; obtains the intermediate matrix according to the adjacent point aggregation operator matrix and the inter-point diffusion operator matrix; assigns a value to an item in the target threshold matrix according to the value of each item of data in the intermediate matrix; iterates the adjacent point aggregation operator matrix and the inter-point diffusion operator matrix until each item in the target threshold matrix is ​​assigned a value, and obtains the assigned target threshold matrix; wherein each item in the assigned target threshold matrix represents the gray level of the frequency modulation halftone conversion of the digital image in the screen plate making; and generates the frequency modulation screen according to the assigned target threshold matrix. The efficiency of the frequency modulation halftone conversion of the digital image can be improved, and the problem of low efficiency caused by the traditional error diffusion algorithm can be solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a first flow chart of the method for generating a frequency modulation screen in screen plate making according to an embodiment of the present invention;

[0038] Figure 2 It is a second flow chart of the method for generating a frequency modulation screen in screen plate making according to an embodiment of the present invention;

[0039] Figure 3 Schematic diagram of convolution of an aggregation operator matrix and a diffusion operator matrix according to an embodiment of the present invention;

[0040] Figure 4 It is a model diagram of the aggregation operator matrix iterative calculation function of an embodiment of the present invention;

[0041] Figure 5 is a partial schematic diagram of a target threshold matrix according to an embodiment of the present invention;

[0042] Figure 6 is a schematic diagram of a first dot of a frequency modulated halftone image according to an embodiment of the present invention;

[0043] Figure 7 is a schematic diagram of a second dot of a frequency modulated halftone image according to an embodiment of the present invention;

[0044] Figure 8 It is a structural diagram of the frequency modulation screen generating device in the screen plate making according to an embodiment of the present invention. DETAILED DESCRIPTION

[0045] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0046] like Figure 1 As shown, an embodiment of the present invention provides a method for generating a frequency modulation screen in screen plate making, comprising:

[0047] Step 11, obtaining the target threshold matrix to be assigned, the adjacent point aggregation operator matrix and the point diffusion operator matrix;

[0048] Here, the target threshold matrix to be assigned is an empty matrix that limits the target size, and each item in this empty target threshold matrix can be further assigned according to a certain order and rule. The assigned target threshold matrix can be used to convert the digital image in the screen plate making into a frequency modulated halftone image, that is, the digital image is frequency modulated and screened to obtain a frequency modulated halftone image. The halftone image is relative to the continuous image, such as the printed image of the screen printing, which expresses the image level and color changes through the size or density of the dots. From a microscopic point of view, the details of this type of image change discontinuously, so it is called a halftone image. The dots refer to the clusters of dyeing areas formed by the dyeing points being adjacent to each other in geometric positions.

[0049] Among them, the adjacent point aggregation operator matrix and the point diffusion operator matrix are two attribute operator matrices. In this application, the adjacent point aggregation operator matrix is ​​set as U1, and the point diffusion operator matrix is ​​set as U2.

[0050] Step 12, obtaining an intermediate matrix according to the adjacent point aggregation operator matrix and the inter-point diffusion operator matrix;

[0051] Step 13, assigning a value to an item in the target threshold matrix according to the value of each item of data in the intermediate matrix;

[0052] Here, an item in the target threshold matrix refers to Figure 5 The number in a square in the matrix shown.

[0053] Step 14, iterating the adjacent point aggregation operator matrix and the inter-point diffusion operator matrix until each item in the target threshold matrix is ​​assigned a value, thereby obtaining a target threshold matrix after the assignment; wherein each item in the target threshold matrix after the assignment represents a gray level for frequency modulation halftone conversion of the digital image in the screen plate making;

[0054] Here, each item in the target threshold matrix is ​​assigned a value such as Figure 5 Each square in the matrix shown has a corresponding value. Figure 5 In the target threshold matrix shown, each number represents a gray level, and each gray level is determined by a series of parameters such as halftone dot distribution, dot size, and arrangement. By determining the gray level of the halftone image, the dot distribution, dot size, and arrangement can be controlled according to the gray level, thereby realizing the conversion of the digital image to the halftone image.

[0055] Step 15, generating the frequency modulation network according to the assigned target threshold matrix.

[0056] In this embodiment, Figure 2 As shown, a matrix-based FM screen generation method is involved. On the basis of the halftone AM screening principle based on the threshold matrix method, the basic implementation method of the threshold matrix is ​​fully utilized, and the random distribution modulation of error diffusion and the algorithm mechanism of AM dot aggregation are combined to achieve discrete distribution of dots in a fixed-size matrix area while performing effective partial aggregation of dots as the threshold is increased, which is more in line with the output requirements of the printing process. On the other hand, while ensuring the random dot distribution effect of imitating error diffusion, a table lookup mechanism is adopted, thereby greatly improving the efficiency of FM screen operation, solving the problem of low efficiency caused by the traditional error diffusion algorithm, and fully meeting the normal industrial application efficiency standards.

[0057] In an optional embodiment of the present invention, step 11 may include:

[0058] Step 111, obtaining a target threshold matrix of size W*W, a neighboring point aggregation operator matrix with randomly initialized values, and an inter-point diffusion operator matrix with initialized values ​​as preset values, where W is a positive integer.

[0059] In this embodiment, the target threshold matrix is ​​a square with a side length of W. Let the target threshold matrix be M, and then an initial zero value is assigned to each item in the matrix M. The value of each item in the target threshold matrix M after the assignment determines the order in which the value is "lit up". The order value is expressed as an integer from large to small, and the value range of each item is M[x,y]∈[1,WxW]. The initialization zero value is an unassigned mark. Where x and y represent the index values ​​of the columns and rows in the target threshold matrix, respectively.

[0060] Each item in the adjacent point aggregation operator matrix U1 is initialized to a unique pseudo-random number, and its value range is U1[x,y]∈(0,1]. In this application, a possible implementation method of the adjacent point aggregation operator matrix U1 is as follows:

[0061] U1=(a×x+b×y)mod(c)÷255

[0062] Among them, x, y represent the horizontal and vertical coordinates of each value in the matrix U1, and the three values ​​of a, b, and c are three positive integers that are prime to each other, and their values ​​must ensure that (a, b, c)∈[0,255].

[0063] Each item in the inter-point diffusion operator matrix U2 is initialized to a preset value, which is preferably 1.0. In the subsequent iterative operation process, the value range of the matrix U2 is U2[x,y]∈[1,AxA], where A is the side length of the square matrix U2 and A is a positive integer.

[0064] In an optional embodiment of the present invention, step 12 may include:

[0065] Step 121, performing matrix convolution on the adjacent point aggregation operator matrix and the point diffusion operator matrix to obtain an intermediate matrix; the intermediate matrix is ​​equal in size to the target threshold matrix.

[0066] In this embodiment, there is no restriction on the size of the adjacent point aggregation operator matrix and the inter-point diffusion operator matrix. Figure 3 As shown in the figure, the 3*3 size is the point diffusion operator matrix, and the 10*10 size is the adjacent point aggregation operator matrix. By controlling the convolution step size and padding value, an intermediate matrix equal to the target threshold matrix size is obtained.

[0067] In an optional embodiment of the present invention, step 13 may include:

[0068] Step 131, determining a data item with the largest value in the intermediate matrix according to the value of each data item in the intermediate matrix;

[0069] Step 132, assigning a value to an item corresponding to the index coordinate value in the target threshold matrix according to the index coordinate value of the item of data with the largest value.

[0070] In this embodiment, the size of each data item in the intermediate matrix U3 is counted to find the maximum value U3[x max ,y max ], which corresponds to the index coordinate [x max ,y max ]. The index coordinates [x max ,y max] The corresponding position item is assigned an integer C. When the intermediate matrix is ​​obtained for the first time after the neighboring point aggregation operator matrix and the point diffusion operator matrix are initialized, the item corresponding to the maximum value coordinate in the target threshold matrix M is assigned 1, that is, C takes the value of 1 at this time. During the iteration process of the neighboring point aggregation operator matrix and the point diffusion operator matrix, the value of the corresponding item of the target threshold matrix M increases by 1 for each iteration.

[0071] In an optional embodiment of the present invention, step 14 may include:

[0072] Step 141, iterating the adjacent point aggregation operator matrix and the point diffusion operator matrix to obtain an iterated adjacent point aggregation operator matrix and point diffusion operator matrix;

[0073] Step 142, obtaining a new intermediate matrix according to the iterated adjacent point aggregation operator matrix and the inter-point diffusion operator matrix;

[0074] Step 143, assigning a value to an item in the target threshold matrix according to the value of each item of data in the new intermediate matrix;

[0075] Step 144, repeatedly iterating the adjacent point aggregation operator matrix and the inter-point diffusion operator matrix until each item in the target threshold matrix is ​​assigned a value, thereby obtaining a target threshold matrix after the assignment.

[0076] In this embodiment, each time the adjacent point aggregation operator matrix and the point diffusion operator matrix are iterated once, an item in the target threshold matrix is ​​assigned a value. If each item in the target threshold matrix of size W*W is assigned a value, it needs to be iterated W*W-1 times. During each iteration, the assignment items of the target threshold matrix are determined according to the coordinates of the maximum value in the intermediate matrix, so that each item in the target threshold matrix is ​​assigned a value at intervals, and finally a complete target threshold matrix is ​​obtained.

[0077] In an optional embodiment of the present invention, step 141 may include:

[0078] Step 1411, multiplying the adjacent point aggregation operator matrix by a preset function to obtain an iterated adjacent point aggregation operator matrix;

[0079] Step 1412: Subtract a preset value from the inter-point diffusion operator matrix to obtain an iterated inter-point diffusion operator matrix.

[0080] In this embodiment, the iteration method of the adjacent point aggregation operator matrix adopts the following formula:

[0081] U1[x,y]=U1[x,y]×F(d)

[0082] Where [x, y] represents the index coordinate value of each table item in the U1 matrix, and the F(d) function equation satisfies the ringing effect law and is composed of multiple straight line equations. Its change law is consistent with the initial amplitude being large, and as the density of the distribution points changes, its single-point amplitude gradually tends to a stable value. The F(d) function is as follows:

[0083]

[0084] in, f is the cutoff frequency of the single-point distribution of the frequency modulation network, and is also the reciprocal of the mean of the distances between the assigned items in the target threshold matrix. f can be expressed as f = 1 / ∑r, where r is the distance between the two items.

[0085] The adjacent point aggregation operator matrix iterative calculation function model diagram is as follows Figure 4 shown.

[0086] The iteration method of the inter-point diffusion operator matrix adopts the following formula:

[0087] U2[x,y]=U2[x,y]-h

[0088] where h is defined as follows:

[0089] h=exp(-r 2 / d 2 ) / ∑exp(-r 2 / d 2 )

[0090] Where r is the average distance between two items,

[0091] In an optional embodiment of the present invention, step 143 may include:

[0092] Step 1431, determining a data item with the largest value in the new intermediate matrix according to the value of each data item in the new intermediate matrix;

[0093] Step 1432, assign a value to an item corresponding to the index coordinate value in the target threshold matrix according to the index coordinate value of the item of data with the largest value; each time the intermediate matrix is ​​updated, the value assigned in the target threshold matrix is ​​increased by one.

[0094] In this embodiment, the intermediate matrix is ​​continuously iterated, and each item in the target threshold matrix is ​​gradually assigned a value. It should be noted that in this application, each item in the target threshold matrix is ​​assigned in the order of priority, and the value of each item increases by 1 each time. For example, in one iteration, an item with an index coordinate value of [3,2] is assigned a value of 5; after the next iteration, the index coordinate value of the maximum value in the intermediate matrix is ​​[5,8], then an item with a coordinate value of [5,8] in the target threshold matrix is ​​assigned a value of 6; continuing the next iteration, the corresponding item is assigned a value of 7, and so on. The local effect diagram of the target threshold matrix after the final assignment is shown in the figure. Figure 5 As shown, you can see that the integers are arranged at intervals and each item is assigned a value.

[0095] As mentioned above, each item in the target threshold matrix represents a gray level, and the dot effect of the generated halftone image is controlled according to the gray level. Figure 6 and Figure 7 As shown in FIG. 1 , it is a schematic diagram of the dot effect of the halftone image generated at the grayscale level of different target threshold matrices. Figure 7 The gray level is higher than Figure 6 Gray levels.

[0096] The present invention will be further described below in conjunction with embodiments:

[0097] Embodiment 1,

[0098] Step 1: Set the target threshold matrix M, which contains a series of digital arrays such as halftone dot distribution, dot size, and arrangement. The matrix is ​​square with a side length of 128. Assign an initial zero value to each item in the matrix M. The value of each item in the matrix M depends on the order in which the value is "lit up". The order value is expressed as an integer from large to small, and the value range of each item is M[x,y]∈[1,128x128]. The initial zero value is an unassigned mark. Where x and y represent the index values ​​of the column and row in the matrix respectively.

[0099] Step 2: Set two attribute operator matrices U1 and U2 of the same size as the M matrix. The operator matrix U1 is the neighboring point aggregation operator matrix, and U2 is the inter-point diffusion operator matrix. Initialize each item U1[x,y] in the U1 matrix with a unique pseudo-random number.

[0100] U1[x,y]=(a×x+b×y)mod(c)÷255

[0101] Wherein: x, y represent the horizontal and vertical coordinates of each value in the matrix U1, and a, b, c are three positive integers that are prime to each other. In this embodiment, the calculation formulas of parameters a, b, c are as follows:

[0102] T n=Tr n-1 +Tr n-2 +Tr n-3 (For n>2)

[0103] Among them: Tr0 = 0, Tr1 = 1, Tr2 = 1. Calculate Tr3, Tr4, Tr5 in turn as the values ​​of parameters a, b, c respectively. The value range is U1[x, y]∈(0,1].

[0104] At the same time, each item U2[x,y] in the U2 matrix is ​​initialized to 1.0.

[0105] Step 3: For the attribute operator matrices U1 and U2, perform matrix convolution calculation to obtain the intermediate matrix U3. The calculation process is as follows: in: Represents the convolution operation. Count the size of each data item in U3 and find the maximum value U3[x max ,y max ], the index coordinate corresponding to this value [x max ,y max ]In the matrix M, the position item is assigned an integer C, C is an incremental item, and its value range is [1,WxW]. After each assignment of M, C increases by 1.

[0106] Step 4: Iterate the values ​​of the operator matrix U1.

[0107] Step 5: Iterate the values ​​in the operator matrix U2.

[0108] Step 6: Repeat steps 3 to 5 until all points in M ​​are “lit up” in turn and assigned values ​​from 1 to W×W in sequence.

[0109] The above method of the present invention can give full play to the characteristics of multi-bit imaging devices based on the threshold matrix lookup table method halftone screening algorithm according to the device imaging requirements for dots, and compared with the traditional multi-level grayscale error diffusion frequency modulation screen algorithm, while ensuring the quality of multi-level grayscale gradation, it greatly improves the frequency modulation screen operation efficiency. The method of the present invention can efficiently complete the frequency modulation screen output on a multi-bit depth output device without losing quality.

[0110] like Figure 8 As shown, the present invention also provides a frequency modulation screen generating device 80 in screen plate making, comprising:

[0111] An acquisition module 81 is used to acquire a target threshold matrix to be assigned, a neighboring point aggregation operator matrix and an inter-point diffusion operator matrix;

[0112] The processing module 82 is used to obtain an intermediate matrix according to the adjacent point aggregation operator matrix and the point diffusion operator matrix; assign a value to an item in the target threshold matrix according to the value of each data item in the intermediate matrix; iterate the adjacent point aggregation operator matrix and the point diffusion operator matrix until each item in the target threshold matrix is ​​assigned a value, thereby obtaining the assigned target threshold matrix; wherein each item in the assigned target threshold matrix represents a grayscale level for frequency modulation halftone conversion of a digital image in screen platemaking; and generate the frequency modulation screen according to the assigned target threshold matrix.

[0113] Optionally, obtain the target threshold matrix to be assigned, the adjacent point aggregation operator matrix, and the point diffusion operator matrix, including:

[0114] Obtain a target threshold matrix of size W*W, a neighboring point aggregation operator matrix with randomly initialized values, and an inter-point diffusion operator matrix with initialized values ​​of preset values, where W is a positive integer.

[0115] Optionally, an intermediate matrix is ​​obtained according to the adjacent point aggregation operator matrix and the point diffusion operator matrix, including:

[0116] Perform matrix convolution on the adjacent point aggregation operator matrix and the point diffusion operator matrix to obtain an intermediate matrix; the intermediate matrix is ​​equal to the target threshold matrix in size.

[0117] Optionally, assigning a value to an item in the target threshold matrix according to the value of each item of data in the intermediate matrix includes:

[0118] According to the value of each item of data in the intermediate matrix, determining the item of data with the largest value in the intermediate matrix;

[0119] According to the index coordinate value of the data item with the largest value, an item corresponding to the index coordinate value in the target threshold matrix is ​​assigned a value.

[0120] Optionally, the adjacent point aggregation operator matrix and the point diffusion operator matrix are iterated until each item in the target threshold matrix is ​​assigned a value, and the assigned target threshold matrix is ​​obtained, including:

[0121] Iterating the adjacent point aggregation operator matrix and the point diffusion operator matrix to obtain an iterated adjacent point aggregation operator matrix and point diffusion operator matrix;

[0122] Obtaining a new intermediate matrix according to the iterated adjacent point aggregation operator matrix and the inter-point diffusion operator matrix;

[0123] Assign a value to an item in the target threshold matrix according to the value of each item of data in the new intermediate matrix;

[0124] The adjacent point aggregation operator matrix and the inter-point diffusion operator matrix are repeatedly iterated until each item in the target threshold matrix is ​​assigned a value, thereby obtaining a target threshold matrix after the assignment.

[0125] Optionally, iterating the adjacent point aggregation operator matrix and the point diffusion operator matrix to obtain the iterated adjacent point aggregation operator matrix and the point diffusion operator matrix includes:

[0126] Multiplying the adjacent point aggregation operator matrix by a preset function to obtain an iterated adjacent point aggregation operator matrix;

[0127] A preset value is subtracted from the inter-point diffusion operator matrix to obtain an iterated inter-point diffusion operator matrix.

[0128] Optionally, assigning a value to an item in the target threshold matrix according to the value of each item of data in the new intermediate matrix includes:

[0129] According to the value of each item of data in the new intermediate matrix, determining the item of data with the largest value in the new intermediate matrix;

[0130] According to the index coordinate value of the data item with the largest value, a value is assigned to an item corresponding to the index coordinate value in the target threshold matrix; each time the intermediate matrix is ​​updated, the value assigned in the target threshold matrix is ​​increased by one.

[0131] It should be noted that the device is a device corresponding to the above method, and all implementation methods in the above method embodiments are applicable to the embodiments of the device and can achieve the same technical effects.

[0132] The embodiment of the present invention further provides a computing device, comprising: a processor, a memory storing a computer program, wherein when the computer program is executed by the processor, the method described above is executed. All implementations in the above method embodiment are applicable to this embodiment and can achieve the same technical effect.

[0133] The embodiment of the present invention further provides a computer-readable storage medium storing instructions, which, when executed on a computer, enable the computer to execute the above method. All implementations in the above method embodiment are applicable to this embodiment and can achieve the same technical effect.

[0134] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of 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 the present invention.

[0135] 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.

[0136] In the embodiments provided by the present invention, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0137] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0138] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0139] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard disks, ROM, RAM, magnetic disks, or optical disks.

[0140] In addition, it should be noted that in the apparatus and method of the present invention, it is obvious that each component or each step can be decomposed and / or recombined. These decompositions and / or recombinations should be regarded as equivalent schemes of the present invention. Moreover, the steps of performing the above-mentioned series of processing can naturally be performed in chronological order according to the order of description, but it is not necessary to perform them in chronological order, and some steps can be performed in parallel or independently of each other. For those of ordinary skill in the art, it is understood that all or any steps or components of the method and apparatus of the present invention can be implemented in any computing device (including processors, storage media, etc.) or a network of computing devices in hardware, firmware, software or a combination thereof, which can be achieved by those of ordinary skill in the art using their basic programming skills after reading the description of the present invention.

[0141] Therefore, the purpose of the present invention can also be achieved by running a program or a group of programs on any computing device. The computing device can be a well-known general device. Therefore, the purpose of the present invention can also be achieved by simply providing a program product containing a program code that implements the method or device. That is to say, such a program product also constitutes the present invention, and the storage medium storing such a program product also constitutes the present invention. Obviously, the storage medium can be any well-known storage medium or any storage medium developed in the future. It should also be pointed out that in the device and method of the present invention, it is obvious that each component or each step can be decomposed and / or recombined. These decompositions and / or recombinations should be regarded as equivalent schemes of the present invention. In addition, the steps of performing the above-mentioned series of processing can naturally be performed in chronological order according to the order of description, but it is not necessary to perform them in chronological order. Some steps can be performed in parallel or independently of each other.

[0142] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for generating a frequency modulation screen in screen plate making, characterized in that: include: Obtain the target threshold matrix to be assigned, the adjacent point aggregation operator matrix and the point diffusion operator matrix; Obtaining an intermediate matrix according to the adjacent point aggregation operator matrix and the inter-point diffusion operator matrix; Assign a value to an item in the target threshold matrix according to the value of each item of data in the intermediate matrix; Iterating the adjacent point aggregation operator matrix and the inter-point diffusion operator matrix until each item in the target threshold matrix is ​​assigned a value, thereby obtaining a target threshold matrix after the assignment; wherein each item in the target threshold matrix after the assignment represents a gray level for frequency modulation halftone conversion of a digital image in screen plate making; The frequency modulation network is generated according to the assigned target threshold matrix.

2. The method for generating a frequency modulated screen in screen plate making according to claim 1, characterized in that: Obtain the target threshold matrix, adjacent point aggregation operator matrix and inter-point diffusion operator matrix to be assigned, including: Obtain a target threshold matrix of size W*W, a neighboring point aggregation operator matrix with randomly initialized values, and an inter-point diffusion operator matrix with initialized values ​​of preset values, where W is a positive integer.

3. The method for generating a frequency modulated screen in screen plate making according to claim 1, characterized in that: According to the adjacent point aggregation operator matrix and the point diffusion operator matrix, an intermediate matrix is ​​obtained, including: Perform matrix convolution on the adjacent point aggregation operator matrix and the point diffusion operator matrix to obtain an intermediate matrix; the intermediate matrix is ​​equal to the target threshold matrix in size.

4. The method for generating a frequency modulated screen in screen plate making according to claim 1, characterized in that: Assigning a value to an item in the target threshold matrix according to the value of each item of data in the intermediate matrix includes: According to the value of each item of data in the intermediate matrix, determining the item of data with the largest value in the intermediate matrix; According to the index coordinate value of the data item with the largest value, an item corresponding to the index coordinate value in the target threshold matrix is ​​assigned a value.

5. The method for generating frequency modulation screen in screen plate making according to claim 1, characterized in that: The adjacent point aggregation operator matrix and the point diffusion operator matrix are iterated until each item in the target threshold matrix is ​​assigned a value, and the assigned target threshold matrix is ​​obtained, including: Iterating the adjacent point aggregation operator matrix and the point diffusion operator matrix to obtain an iterated adjacent point aggregation operator matrix and point diffusion operator matrix; Obtaining a new intermediate matrix according to the iterated adjacent point aggregation operator matrix and the inter-point diffusion operator matrix; Assign a value to an item in the target threshold matrix according to the value of each item of data in the new intermediate matrix; The adjacent point aggregation operator matrix and the inter-point diffusion operator matrix are repeatedly iterated until each item in the target threshold matrix is ​​assigned a value, thereby obtaining a target threshold matrix after the assignment.

6. The method for generating a frequency modulated screen in screen plate making according to claim 5, characterized in that: Iterating the adjacent point aggregation operator matrix and the point diffusion operator matrix to obtain the iterated adjacent point aggregation operator matrix and the point diffusion operator matrix, including: Multiplying the adjacent point aggregation operator matrix by a preset function to obtain an iterated adjacent point aggregation operator matrix; A preset value is subtracted from the inter-point diffusion operator matrix to obtain an iterated inter-point diffusion operator matrix.

7. The method for generating a frequency modulation screen in screen plate making according to claim 5, characterized in that: Assigning a value to an item in the target threshold matrix according to the value of each item of data in the new intermediate matrix, including: According to the value of each item of data in the new intermediate matrix, determining the item of data with the largest value in the new intermediate matrix; According to the index coordinate value of the data item with the largest value, a value is assigned to an item corresponding to the index coordinate value in the target threshold matrix; each time the intermediate matrix is ​​updated, the value assigned in the target threshold matrix is ​​increased by one.

8. A frequency modulation network generation device in screen plate making, characterized in that: include: An acquisition module is used to obtain a target threshold matrix to be assigned, a neighboring point aggregation operator matrix, and an inter-point diffusion operator matrix; A processing module is used to obtain an intermediate matrix according to the adjacent point aggregation operator matrix and the point diffusion operator matrix; assign a value to an item in the target threshold matrix according to the value of each item of data in the intermediate matrix; iterate the adjacent point aggregation operator matrix and the point diffusion operator matrix until each item in the target threshold matrix is ​​assigned a value, thereby obtaining the assigned target threshold matrix; wherein each item in the assigned target threshold matrix represents a grayscale level for frequency modulation halftone conversion of a digital image in screen platemaking; and generate the frequency modulation screen according to the assigned target threshold matrix.

9. A computing device, characterized in that include: A processor and a memory storing a computer program, wherein when the computer program is executed by the processor, the method according to any one of claims 1 to 7 is performed.

10. A computer-readable storage medium, characterized in that: Instructions are stored, and when the instructions are executed on a computer, the computer is caused to execute the method according to any one of claims 1 to 7.

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