A method for improving the clarity of electrophoretic display images

Abstract

The present invention relates to a method for improving the clarity of an electrophoretic display image, the steps of which include: determining the grayscale value of each pixel in the display image, obtaining a grayscale value matrix A determined by the display image, and setting a threshold value according to the grayscale value distribution law of all pixels in the display image; formulating a processing order for the elements in the grayscale value matrix A; and selecting the first element a from the grayscale value matrix A. 11 Initially, each element in the gray value matrix A is processed in sequence to obtain the gray value matrix B; all elements in the first row, first column, nth row and mth column of the gray value matrix B are replaced with 0 to form a gray value matrix C, and then the gray value inverse matrix C is processed into an image and output; the technical solution of the present application takes into account pixels with gray values ​​near the threshold, thereby improving the clarity of the picture.

Description

Technical Field

[0001] The present invention relates to the field of electrophoretic display, and in particular to a method for improving the clarity of electrophoretic display images. Background Art

[0002] When using electronic paper, images are often blurred. To improve display clarity, grayscale transformation is often used. Grayscale transformation involves changing the grayscale value of each pixel in the source image point by point based on a specific transformation relationship and target conditions. Common grayscale transformation methods include thresholding, linear transformation, and nonlinear transformation.

[0003] In the electrophoretic display process, a threshold method is often used to process images to improve image clarity. This method typically involves setting a threshold in a digital image. For pixels in the digital image with grayscale values ​​less than the threshold, their grayscale values ​​are converted to zero, while for pixels with grayscale values ​​greater than or equal to the threshold, their grayscale values ​​are converted to 255.

[0004] However, this method is too rough in processing pixels whose grayscale values ​​are close to the threshold, especially for those pixels whose grayscale values ​​are very close to the threshold. It lacks special considerations and can easily cause image distortion. Summary of the Invention

[0005] The purpose of the present invention is to overcome the defects of the prior art and provide a method for improving the clarity of electrophoretic display images.

[0006] The present invention provides a method for improving the clarity of electrophoretic display images, and its technical solution is as follows:

[0007] A method for improving the clarity of an electrophoretic display comprises the following steps:

[0008] Step 1: Determine the grayscale value of each pixel in the display image, obtain the grayscale value matrix A determined by the display image, and set a threshold value according to the grayscale value distribution law of all the pixels in the display image, wherein:

[0009] ,

[0010] a ij represents the grayscale value corresponding to the i-th row and j-th column of the display area in the display image, 1≤i≤n, 1≤j≤m;

[0011] Step 2: Establish a processing order for the elements in the gray value matrix A;

[0012] Step 3: From the gray value matrix A, the first element a 11First, each element in the gray value matrix A is processed in sequence according to the processing order. The processing rules are as follows:

[0013] If the element a in the gray value matrix A ij is less than the threshold, then the element a ij Replace it with 0, and change the element a in the gray value matrix A i+k j+l The value is incremented by no more than value a ij The gray value matrix A is increased in the form of, and then the next element in the gray value matrix A is processed in the processing order;

[0014] If the element a in the gray value matrix A ij is not less than the threshold, then the element

[0015] a ij Replace it with 255, and change the element a in the gray value matrix A i+k j+1 The value is reduced by an amount not exceeding the value Δ, where

[0016] Δ=255-a ij

[0017] , and then process the next element in the gray value matrix A according to the processing order;

[0018] where 1≤i≤n, 1≤j≤m, i+k≤n, j+l≤m, and (k,l)∈{(0,1),(1,0),(1,1)}

[0019] Replacing all elements in the gray value matrix A according to the processing rule to form a gray value matrix B;

[0020] Step 4: Replace all elements in the first row, first column, last row, and last column of the gray value matrix B with 0 to form a gray value matrix C;

[0021] Step 5: Process the grayscale value matrix C into an image and output it as a display screen.

[0022] By adopting the above technical solution, compared with the prior art, the technical solution provided by the present invention application can at least bring the following beneficial effects: since the threshold is set according to the grayscale value distribution law of all pixels in the display image, and each element in the pixel value matrix A is replaced according to the processing rules, while scientifically defining the threshold, it also takes into account those pixels whose grayscale values ​​are very close to the threshold, so that such pixels will not be arbitrarily binarized. In addition, the processing of replacing the border elements in the pixel value matrix B with 0 effectively ensures the clarity of the image display.

[0023] Preferably, in step 1, the process of setting a threshold value according to the grayscale value distribution rule of all the pixels in the display image includes the following steps:

[0024] Step 1.1, obtaining the median of the grayscale value of the display screen according to the grayscale value distribution information of the display screen;

[0025] Step 1.2, setting the median as a threshold;

[0026] This article takes into account the pixel distribution pattern of the display screen when determining the threshold. By finding the median of the grayscale value and setting it as the threshold, it can scientifically and reasonably distinguish between dark spots and bright spots in the display screen.

[0027] Preferably, the processing sequence includes a first sequence τ1 or a second sequence τ2, and the first sequence τ1 is:

[0028] a 11 →a 12 →…→a 1m →a 21 →…→a 2m →…→a nm

[0029] , the second order τ2 is:

[0030] a 11 →a 21 →…→a n1 →a 12 →…→a n2 →…→a nm ;

[0031] This ensures the orderly operation of the algorithm program and reduces the computational complexity. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a flow chart of a method for improving the clarity of electrophoretic display images according to the present invention; DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention.

[0034] Example 1

[0035] An embodiment of the present invention provides a method for improving the clarity of an electrophoretic display image, comprising the following steps:

[0036] Step 1: Obtain the grayscale value of the display area in the display image through digital processing to form a grayscale value matrix A corresponding to the display image, and set a threshold value according to the grayscale value distribution law of all pixels in the display image, where:

[0037] ,

[0038] a ij Represents the grayscale value corresponding to the i-th row and j-th column of the display area in the display image, 1≤i≤n, 1≤j≤m.

[0039] In this embodiment, the process of setting the threshold value according to the grayscale value distribution of all pixels in the display image in step 1 includes the following steps:

[0040] Step 1.1, obtaining the median of the grayscale value of the display screen according to the grayscale value distribution information of the display screen;

[0041] Step 1.2: Set the median as the threshold.

[0042] Step 2: Establish a processing order for the elements in the gray value matrix A.

[0043] The processing sequence τ1 in this embodiment is:

[0044] a 11 →a 12 →…→a 1m →a 21 →…→a 2m →…→a nm

[0045] Step 3: From the gray value matrix A, the first element a 11 First, each element in the gray value matrix A is processed in the order specified by the processing sequence τ1. The processing rules are as follows:

[0046] When the element a in the gray value matrix A ij When it is less than the threshold, element a ij Replace with 0, and change the element a in the gray value matrix A i+k j+l The value is incremented by no more than value a ij After the processing is completed, the next element in the gray value matrix A is processed in this order;

[0047] When the element a in the gray value matrix A ij When it is not less than the threshold, element a ij Replace it with 255 and change the element a in the gray value matrix A i+k j+l The value is reduced by an amount not exceeding the value Δ, where

[0048] Δ=255-a ij

[0049] , after the processing is completed, the next element in the gray value matrix A is processed in this order;

[0050] Among them, 1≤i≤n, 1≤j≤m, i+k≤n, j+l≤m, and,

[0051] (k, l)∈{(0, 1), (1, 0), (1, 1)}

[0052] According to the processing rule, all elements of the gray value matrix A are replaced to form a gray value matrix B;

[0053] Step 4: Replace all elements in the first row, first column, nth row, and mth column of the gray value matrix B with 0 to form a gray value matrix C;

[0054] Step 5: Convert the grayscale value matrix C into an image and output it as a display screen.

[0055] Example 2

[0056] The processing sequence in this embodiment adopts the sequence τ2, where the sequence τ2 is:

[0057] a 11 →a 21 →…→a n1 →a 12 →…→a n2 →…→a nm .

[0058] The rest of the content is the same as that of the first embodiment.

[0059] Regardless of embodiment 1 or embodiment 2, the element a in the gray value matrix A is i+kj+l The value increase or decrease can be determined according to the energy distribution or transfer rules, provided that the corresponding requirements are met. For the case of i+k>n or j+l>m, since there is no corresponding element in the pixel value matrix A, no increase or decrease can be allocated.

[0060] In summary, although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for improving the clarity of an electrophoretic display, characterized by: The steps include: Step 1: Determine the grayscale value of each pixel in the display image, obtain the grayscale value matrix A determined by the display image, and set a threshold value according to the grayscale value distribution law of all the pixels in the display image, wherein: ， a ij represents the grayscale value corresponding to the i-th row and j-th column of the display area in the display image, 1≤i≤n, 1≤j≤m; Step 2: Establish a processing order for the elements in the gray value matrix A; Step 3: From the gray value matrix A, the first element a 11 First, each element in the gray value matrix A is processed in sequence according to the processing order. The processing rules are as follows: If the element a in the gray value matrix A ij is less than the threshold, then the element a ij Replace it with 0, and change the element a in the gray value matrix A i+k j+1 The value is incremented by no more than value a ij The gray value matrix A is increased in the form of, and then the next element in the gray value matrix A is processed in the processing order; If the element a in the gray value matrix A ij is not less than the threshold, then the element a ij Replace it with 255, and change the element a in the gray value matrix A i+k j+l The value is reduced by an amount not exceeding the value Δ, where Δ=255-a ij , and then process the next element in the gray value matrix A according to the processing order; Among them, 1≤i≤n, 1≤j≤m, i+k≤n, j+l≤m, and, (k, l)∈{(0, 1), (1, 0), (1, 1)} replaces all elements in the gray value matrix A according to the processing rule to form a gray value matrix B; Step 4: Replace all elements in the first row, first column, last row, and last column of the gray value matrix B with 0 to form a gray value matrix C; Step 5: Process the grayscale value matrix C into an image and output it as a display screen.

2. The method for improving the clarity of electrophoretic display according to claim 1, wherein: In step 1, the process of setting a threshold value according to the grayscale value distribution rule of all the pixels in the display image includes the following steps: Step 1.1, obtaining the median of the grayscale value of the display image according to the grayscale value distribution information of the display image; Step 1.2: Set the median as the threshold.

3. The method for improving the clarity of electrophoretic display according to claim 2, wherein: The processing sequence includes a first sequence τ1 or a second sequence τ2, wherein the first sequence τ1 is: a 11 →a 12 →…→a 1m →a 21 →…→a 2m →…→a nm , the second order τ2 is: a 11 →a 21 →…→a n1 →a 12 →…→a n2 →…→a nm 。

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