CN114022415A - Liquid crystal display defect detection method based on single-pixel feature clustering cluster establishment - Google Patents

Liquid crystal display defect detection method based on single-pixel feature clustering cluster establishment Download PDF

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CN114022415A
CN114022415A CN202111204952.1A CN202111204952A CN114022415A CN 114022415 A CN114022415 A CN 114022415A CN 202111204952 A CN202111204952 A CN 202111204952A CN 114022415 A CN114022415 A CN 114022415A
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漆长松
李勇
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Chengdu Botovision Technology Co ltd
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Abstract

The invention provides a liquid crystal display defect detection method for establishing a cluster based on single-pixel characteristic clustering, which comprises the steps of firstly, obtaining an RGB three-channel image of a liquid crystal display, and also comprises the step of S1, obtaining gray values and r, g and b channel values of each pixel point of the image, and converting the image into a gray image; s2, performing traversal calculation on each pixel point in the gray-scale image, and generating a feature vector of each pixel point through a multi-mode and multi-scale feature extraction kernel; s3, judging whether the liquid crystal screen has defects or not according to the feature vector clustering result and the coordinate distribution condition of the pixel points in the clustered cluster; by adopting the method, the defect samples do not need to be collected, the method is more practical in the algorithm landing application, and the efficiency of the defect detection algorithm is effectively improved due to the small scale of the parameters; in addition, compared with the traditional algorithms such as local pixel values and the like, the defect detection provided by the method is more comprehensive.

Description

Liquid crystal display defect detection method based on single-pixel feature clustering cluster establishment
Technical Field
The invention relates to the technical field of liquid crystal display detection, in particular to a liquid crystal display defect detection method based on single-pixel feature clustering cluster establishment.
Background
Mobile technology devices, such as mobile phones, VR (Virtual Reality) devices, and the like, have not yet developed display screens. In production, the defect detection of the display screen is an essential step. The defects of the liquid crystal display screen are of various types and are very difficult to detect.
In contrast, the conventional detection method is manual detection, which has high requirements on inspectors, and the defects of the inspectors are detected manually for a long time, so that the eyes of the inspectors are greatly damaged, such as vision loss; in addition, the inspector works for a long time and is tired, so that the inspection omission is caused, and the probability that defective products flow into the market is increased.
In order to overcome the defects of manual detection, a defect analysis method based on image analysis is also provided; for example, in the method, the system and the device for detecting the defect of the liquid crystal screen based on the small sample deep learning of the chinese patent with the publication number CN109242829A, the defect detection model is trained by collecting the defect sample, but the occurrence of the defect is unknown, and then the color feature, the pixel size and the shape after the defect imaging are unknown, so that even if the defect detection model can be obtained based on the small sample training, the generalization capability of the model is limited; also, for example, chinese patent publication No. CN104978748A discloses a method for detecting defects of a liquid crystal panel based on local pixel values, which detects defects by calculating local pixels, but the local pixel calculation is based on the premise that an image is divided into mesh-shaped pixel blocks to perform local observation, but if the defect area is large, abnormality cannot be observed in the local mesh-shaped pixel blocks.
In view of the defects in the prior art, the difficulty of visual detection of the liquid crystal display is analyzed, and the defects mainly comprise the defects with no rule and weak difference; the defect forms (such as defect color, defect outline and defect zigzag) are irregular; the defect types of the same liquid crystal screen can be various; aiming at the detection difficulty, the invention provides a novel liquid crystal display defect detection method, so that the defect detection with better accuracy can be realized while the problems are solved.
Disclosure of Invention
The invention aims to provide a liquid crystal display defect detection method for establishing a cluster based on single-pixel characteristic clustering, which does not need to collect defect samples, is more practical in algorithm floor application, and effectively improves the efficiency of a defect detection algorithm due to small scale of parameters; in addition, compared with the traditional algorithms such as local pixel values and the like, the defect detection provided by the method is more comprehensive.
The embodiment of the invention is realized by the following technical scheme:
in a first aspect, a method for detecting defects of a liquid crystal display based on single-pixel feature clustering cluster establishment is provided, which includes the following steps:
s1, obtaining gray values and r, g and b channel values of all pixel points of the image, and converting the image into a gray map;
s2, performing traversal calculation on each pixel point in the gray-scale image, and generating a feature vector of each pixel point through a multi-mode and multi-scale feature extraction kernel;
s3, dividing the pixel points into two first clusters according to the result of the feature vector clustering, filtering the clusters to generate a second cluster, and if the second cluster is generated and the number of the pixel points in the second cluster is greater than a first threshold value, possibly having defects; if a second cluster is not generated and the difference value of the pixel points between the two first clusters is greater than a second threshold value, a defect may exist; and under the condition that defects possibly exist, judging whether the coordinate distribution of the pixel point of one first cluster or the second cluster with smaller pixel points in the first cluster is discrete, if so, judging that the first cluster or the second cluster is not defective, otherwise, judging that the first cluster or the second cluster is defective.
Further, the traversing calculation of each pixel point in the gray-scale map specifically includes:
by pixel points
Figure BDA0003306469940000033
Taking the local image area matrix with the same size as the characteristic extraction kernel as the center through sampling
Figure BDA0003306469940000034
Matrix multiplication or matrix subtraction is carried out;
the feature extraction kernel is a two-dimensional matrix f with the size of m × mm*m
Wherein, the matrix multiplication operation is the multiplication of the two-dimensional matrix of the feature extraction kernel and the local image area matrix, as the following formula (1),
Figure BDA0003306469940000031
the matrix subtraction is to subtract a local image area matrix from a feature extraction kernel two-dimensional matrix, as shown in the following formula (2),
Figure BDA0003306469940000032
wherein,
Figure BDA0003306469940000035
to the pixel point
Figure BDA0003306469940000088
The local image area matrix obtained for center sampling
Figure BDA0003306469940000037
And the feature extraction kernel two-dimensional matrix fm*mThe result after multiplication or subtraction.
Further, the generating of the feature vector of the pixel point by the multi-modal and multi-scale feature extraction kernel specifically includes:
the multi-scale value, namely the size m of the feature extraction kernel, comprises a plurality of values, and the multi-scale value is the feature value in the feature extraction kernel
Figure BDA0003306469940000038
The definition of (a) includes a plurality;
and generating the feature vector of the pixel point according to the multi-modal feature value definition and different values of the multi-scale feature extraction kernel
Figure BDA0003306469940000041
Further, the S3 specifically includes:
s31, selecting one pixel point as a clustering initial center, traversing all other pixel points of the image, and calculating the Euclidean distance between the clustering initial center and the feature vectors of all other pixel points;
s32, screening out two pixel points with the maximum Euclidean distance from the characteristic vector of the clustering initial center as second clustering centers a and b;
s33, respectively calculating characteristic vector Euclidean distances between each pixel point and the second clustering center a and the second clustering center B, and classifying all the pixel points to obtain a first cluster A of the second clustering center a and a first cluster B of the second clustering center B;
s34, filtering the first cluster A and the first cluster B to generate a second cluster C, and judging whether defects exist or not according to whether the second cluster C is generated or not and the number of pixel points contained in the second cluster C;
and S35, according to the judgment result of the S34, judging whether the defect exists or not by combining the coordinate distribution of the pixel points in the first cluster A, the first cluster B and the second cluster C.
Further, the classifying all the pixel points in S33 specifically includes:
and when the Euclidean distance between the pixel point and the characteristic vector of the second clustering center a is greater than that between the pixel point and the characteristic vector of the second clustering center B, classifying the pixel point as a first cluster A, otherwise, classifying the pixel point as a first cluster B.
Further, the filtering process in S34 specifically includes:
calculating characteristic vector Euclidean distances between all pixel points in the first cluster A and the second cluster center a, and calculating and obtaining a characteristic vector Euclidean distance mean value dAThe characteristic vector Euclidean distance between the first cluster center a and the second cluster center a is larger than j x dAThe pixel points of (a) are deleted from the first cluster a and added to the second cluster C, where j is a constant term.
Further, the specific step of judging whether a defect may exist according to whether the second cluster C is generated or not and the number of pixels included in the second cluster C is as follows:
when a second cluster C is generated and the number of pixel points in the second cluster C is more than 5, judging that a defect possibly exists;
when the second cluster C is not generated, whether the difference of the pixel point numbers of the first cluster A and the first cluster B is larger than 1/3 of the total pixel point number of the image is judged, and if the difference is larger than 1/3, the defect is judged to exist.
Further, the S35 specifically includes:
under the condition that a second cluster C appears and the number of pixel points in the second cluster C is more than 5, calculating whether the coordinate distribution of the pixel points in the second cluster C is discrete or not; under the condition that the second cluster C does not appear, selecting a cluster with a small number of pixel points in the first cluster A and the first cluster B, defining the cluster as a cluster Q, and calculating whether the pixel coordinate distribution of the pixel points in the cluster Q is discrete or not; and if the pixel point coordinates are distributed in a discrete manner, judging that no defect exists, and if the pixel point coordinates are distributed in an independently polymerizable region, judging that the defect occurs.
Further, whether the coordinate distribution of the pixel points is discrete specifically is:
setting a pixel point coordinate distribution distance threshold d, wherein the distance threshold
Figure BDA0003306469940000051
Wherein IwRepresenting the pixel width, I, of an imagehIndicating that the image pixel is high; sequentially traversing the pixel points in the cluster Q or the second cluster C, and calculating the coordinate distribution distance value d of every two pixel points in the cluster Q or the second cluster CPIf d isPD is less than or equal to d, the two pixel points are the coordinate cluster set of the similar pixel points, and the total number N of the newly clustered coordinate distribution clusters is obtainedd
Presetting a third threshold value T, wherein T is k NtWhere k is a constant term, NtThe total number of pixel points of the cluster Q or the second cluster C is NdWhen the number of the pixels in the cluster Q is larger than or equal to T, the pixel point coordinate distribution of the second cluster C is considered to be discrete, and the pixel point coordinate distribution is judged to be free of defects; otherwise, the coordinate distribution is considered to be in the independently polymerizable region, and the defect is judged.
In a second aspect, an electronic device is provided that includes a memory and a processor;
the memory stores computer-executable instructions;
the processor executes the computer-executable instructions stored in the memory, so that the processor executes the liquid crystal display defect detection method for establishing the cluster based on the single-pixel characteristic clustering.
The technical scheme of the embodiment of the invention at least has the following advantages and beneficial effects:
(1) compared with the existing deep learning technical scheme based on small samples, the method does not need to collect the defect samples, is more practical in algorithm floor application, and effectively improves the efficiency of the defect detection algorithm due to small scale of parameters;
(2) compared with the traditional algorithms such as local pixel values and the like, the defect detection is more comprehensive, and can be used for detecting the zigzag defects and large-area defects of the liquid crystal display.
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FIG. 1 is a flow chart of the method of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
In a first aspect, a method for detecting defects of a liquid crystal display based on single-pixel feature clustering cluster establishment is provided, and first, an RGB three-channel image of the liquid crystal display is obtained, which further includes the following steps:
s1, obtaining the gray value and the r, g and b channel values of each pixel point of the image, and converting the image into a gray map.
The general formula for converting an RGB three-channel image into a gray scale map is as follows,
Figure BDA0003306469940000071
wherein,
Figure BDA0003306469940000073
representing the gray value of the nth pixel point of the image,
Figure BDA0003306469940000074
respectively representing the r, g and b channel values of the nth pixel point of the image.
Generally, an RGB three-channel image of a liquid crystal panel is an image when the liquid crystal panel displays a single color.
And S2, performing traversal calculation on each pixel point in the gray-scale image, and generating a feature vector of each pixel point through multi-mode and multi-scale feature extraction kernels.
Specifically, each pixel point in the gray-scale map is subjected to traversal calculation, and the pixel points are used for calculation
Figure BDA0003306469940000075
Taking the local image area matrix with the same size as the characteristic extraction kernel as the center through sampling
Figure BDA0003306469940000072
Matrix multiplication or matrix subtraction is carried out;
the feature extraction kernel is a two-dimensional matrix f with the size of m × mm*m
Wherein, the matrix multiplication operation is the multiplication of the two-dimensional matrix of the feature extraction kernel and the local image area matrix, as the following formula (1),
Figure BDA0003306469940000081
Figure BDA0003306469940000082
wherein,
Figure BDA0003306469940000086
the eigenvalues in the feature extraction kernel, i.e., the two-dimensional matrix elements, are represented.
The matrix subtraction is to subtract a local image area matrix from a feature extraction kernel two-dimensional matrix, as shown in the following formula (2),
Figure BDA0003306469940000083
Figure BDA0003306469940000084
wherein,
Figure BDA0003306469940000087
to the pixel point
Figure BDA0003306469940000088
The local image area matrix obtained for center sampling
Figure BDA0003306469940000089
And the feature extraction kernel two-dimensional matrix fm*mThe result after multiplication or subtraction.
It should be noted that the multi-scale, i.e., the size m of the feature extraction kernel, includes a plurality of values, and the multi-scale, i.e., the feature values in the feature extraction kernel
Figure BDA00033064699400000810
The definition of (1) includes various.
In a specific embodiment, the size m of the feature extraction kernel includes 3, 5, and 9; feature values in a feature extraction kernel
Figure BDA00033064699400000811
Representing feature values of n-th row and n-th column in a feature extraction kernel, e.g. in a feature kernel
Figure BDA00033064699400000812
In
Figure BDA0003306469940000085
The specific feature extraction kernel obtained is as follows,
Figure BDA0003306469940000091
Figure BDA0003306469940000092
Figure BDA0003306469940000093
wherein,
Figure BDA0003306469940000094
s is an identity matrix of size m.
And generating the feature vector of the pixel point according to the multi-modal feature value definition and different values of the multi-scale feature extraction kernel
Figure BDA0003306469940000096
As shown in the following formula,
Figure BDA0003306469940000095
s3, dividing the pixel points into two first clusters according to the result of the feature vector clustering, filtering the clusters to generate a second cluster, and if the second cluster is generated and the number of the pixel points in the second cluster is greater than a first threshold value, possibly having defects; if a second cluster is not generated and the difference value of the pixel points between the two first clusters is greater than a second threshold value, a defect may exist; and under the condition that defects possibly exist, judging whether the coordinate distribution of the pixel point of one first cluster or the second cluster with smaller pixel points in the first cluster is discrete, if so, judging that the first cluster or the second cluster is not defective, otherwise, judging that the first cluster or the second cluster is defective.
Specifically, the S3 includes:
s31, selecting one pixel point as a clustering initial center, traversing all other pixel points of the image, and calculating the Euclidean distance between the clustering initial center and the feature vectors of all other pixel points;
s32, screening out two pixel points with the maximum Euclidean distance from the characteristic vector of the clustering initial center as second clustering centers a and b;
s33, respectively calculating characteristic vector Euclidean distances between each pixel point and the second clustering center a and the second clustering center B, and classifying all the pixel points to obtain a first cluster A of the second clustering center a and a first cluster B of the second clustering center B;
it should be noted that the classification method of the pixel point is specifically that, when the euclidean distance between the pixel point and the feature vector of the second clustering center a is greater than the euclidean distance between the pixel point and the feature vector of the second clustering center B, the pixel point is classified as the first cluster a, otherwise, the pixel point is classified as the first cluster B.
S34, filtering the first cluster A and the first cluster B to generate a second cluster C, and judging whether defects exist or not according to whether the second cluster C is generated or not and the number of pixel points contained in the second cluster C;
the filtering process here is specifically to calculate the distance between all the pixel points in the first cluster a and the second cluster center aThe Euclidean distance of the characteristic vector is calculated and obtained, and the mean value d of the Euclidean distance of the characteristic vector is calculated and obtainedAThe characteristic vector Euclidean distance between the first cluster center a and the second cluster center a is larger than j x dAThe pixel points of (a) are deleted from the first cluster a and added to the second cluster C, where j is a constant term.
In a specific embodiment, the value of j is 2, it should be noted that the value of the constant term j can be adjusted according to different liquid crystal screen images to be measured, and in multiple experiments, it is found that the value of j is about 2, which is the most effective section, and the value of j is 2 as the most preferable section.
The specific step of judging whether a defect may exist according to whether the second cluster C is generated or not and the number of pixels included in the second cluster C is as follows:
when a second cluster C is generated and the number of pixel points in the second cluster C is more than 5, judging that a defect possibly exists; it should be noted that, the value 5 may be changed according to different liquid crystal screen images to be measured.
When the second cluster C is not generated, whether the difference of the pixel point numbers of the first cluster A and the first cluster B is larger than 1/3 of the total pixel point number of the image is judged, and if the difference is larger than 1/3, the defect is judged to exist.
And S35, according to the judgment result of the S34, judging whether the defect exists or not by combining the coordinate distribution of the pixel points in the first cluster A, the first cluster B and the second cluster C.
Specifically, S35 is:
under the condition that a second cluster C appears and the number of pixel points in the second cluster C is more than 5, calculating whether the coordinate distribution of the pixel points in the second cluster C is discrete or not; under the condition that the second cluster C does not appear, selecting a cluster with a small number of pixel points in the first cluster A and the first cluster B, defining the cluster as a cluster Q, and calculating whether the pixel coordinate distribution of the pixel points in the cluster Q is discrete or not; and if the pixel point coordinates are distributed in a discrete manner, judging that no defect exists, and if the pixel point coordinates are distributed in an independently polymerizable region, judging that the defect occurs.
Specifically, whether the coordinate distribution of the pixel points is discrete or not is determined by setting the coordinate distribution of the pixel pointsA distance threshold value d, the distance threshold value
Figure BDA0003306469940000111
Wherein IwRepresenting the pixel width, I, of an imagehIndicating that the image pixel is high; sequentially traversing the pixel points in the cluster Q or the second cluster C, and calculating the coordinate distribution distance value d of every two pixel points in the cluster Q or the second cluster CPIf d isPD is less than or equal to d, the two pixel points are the coordinate cluster set of the similar pixel points, and the total number N of the newly clustered coordinate distribution clusters is obtainedd
Presetting a third threshold value T, wherein T is k NtWhere k is a constant term, NtThe total number of pixel points of the cluster Q or the second cluster C is NdWhen the number of the pixels in the cluster Q is larger than or equal to T, the pixel point coordinate distribution of the second cluster C is considered to be discrete, and the pixel point coordinate distribution is judged to be free of defects; otherwise, the coordinate distribution is considered to be in the independently polymerizable region, and the defect is judged.
It should be noted that the value of the constant term k may also vary according to different liquid crystal screen images to be measured, and a large number of experiments show that the preferred value range is 0.15-0.35.
In a second aspect, an electronic device is provided that includes a memory and a processor;
the memory stores computer-executable instructions;
the processor executes the computer-executable instructions stored in the memory, so that the processor executes the liquid crystal display defect detection method for establishing the cluster based on the single-pixel characteristic clustering.
Compared with the prior art, the technical scheme of the invention can bring the following improvement effects,
(1) compared with the existing deep learning technical scheme based on small samples, the method does not need to collect the defect samples, is more practical in algorithm floor application, and effectively improves the efficiency of the defect detection algorithm due to small scale of parameters;
(2) compared with the traditional algorithms such as local pixel values and the like, the defect detection is more comprehensive, and can be used for detecting the zigzag defects and large-area defects of the liquid crystal display.
The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. A liquid crystal screen defect detection method based on single pixel characteristic clustering cluster building cluster is disclosed, firstly, RGB three-channel image of liquid crystal screen is obtained, which is characterized by also comprising the following steps:
s1, obtaining gray values and r, g and b channel values of all pixel points of the image, and converting the image into a gray map;
s2, performing traversal calculation on each pixel point in the gray-scale image, and generating a feature vector of the pixel point through a multi-mode and multi-scale feature extraction kernel;
s3, dividing the pixel points into two first clusters according to the result of the feature vector clustering, filtering the clusters to generate a second cluster, and if the second cluster is generated and the number of the pixel points in the second cluster is greater than a first threshold value, possibly having defects; if a second cluster is not generated and the difference value of the pixel points between the two first clusters is greater than a second threshold value, a defect may exist; and under the condition that defects possibly exist, judging whether the coordinate distribution of the pixel point of one first cluster or the second cluster with smaller pixel points in the first cluster is discrete, if so, judging that the first cluster or the second cluster is not defective, otherwise, judging that the first cluster or the second cluster is defective.
2. The method for detecting defects of a liquid crystal display based on single-pixel feature cluster building cluster according to claim 1, wherein the traversing calculation of each pixel point in the gray-scale map specifically comprises:
by pixel points
Figure FDA0003306469930000011
Taking the local image area matrix with the same size as the characteristic extraction kernel as the center through sampling
Figure FDA0003306469930000012
Then carrying out matrix multiplication or matrix subtraction operation;
the feature extraction kernel is a two-dimensional matrix f with the size of m × mm*m
Wherein, the matrix multiplication operation is the multiplication of the two-dimensional matrix of the feature extraction kernel and the local image area matrix, as the following formula (1),
Figure FDA0003306469930000021
the matrix subtraction is to subtract a local image area matrix from a feature extraction kernel two-dimensional matrix, as shown in the following formula (2),
Figure FDA0003306469930000022
wherein,
Figure FDA0003306469930000023
to the pixel point
Figure DEST_PATH_BDA0003306469940000088
The local image area matrix obtained for center sampling
Figure FDA0003306469930000025
And the feature extraction kernel two-dimensional matrix fm*mThe result after multiplication or subtraction.
3. The method for detecting the defects of the liquid crystal display based on the single-pixel feature cluster building cluster as claimed in claim 2, wherein the feature vectors for generating the pixel points through the multi-modal and multi-scale feature extraction kernel are specifically as follows:
the multi-scale value, namely the size m of the feature extraction kernel, comprises a plurality of values, and the multi-scale value is the feature value in the feature extraction kernel
Figure FDA0003306469930000026
The definition of (a) includes a plurality;
and generating the feature vector of the pixel point according to the multi-modal feature value definition and different values of the multi-scale feature extraction kernel
Figure FDA0003306469930000027
4. The method for detecting defects of a liquid crystal display based on single-pixel feature cluster building cluster according to claim 1, wherein the S3 specifically includes:
s31, selecting one pixel point as a clustering initial center, traversing all other pixel points of the image, and calculating the Euclidean distance between the clustering initial center and the feature vectors of all other pixel points;
s32, screening out two pixel points with the maximum Euclidean distance from the characteristic vector of the clustering initial center as second clustering centers a and b;
s33, respectively calculating characteristic vector Euclidean distances between each pixel point and the second clustering center a and the second clustering center B, and classifying all the pixel points to obtain a first cluster A of the second clustering center a and a first cluster B of the second clustering center B;
s34, filtering the first cluster A and the first cluster B to generate a second cluster C, and judging whether defects exist or not according to whether the second cluster C is generated or not and the number of pixel points contained in the second cluster C;
and S35, according to the judgment result of the S34, judging whether the defect exists or not by combining the coordinate distribution of the pixel points in the first cluster A, the first cluster B and the second cluster C.
5. The method for detecting defects of a liquid crystal display based on single-pixel feature cluster building cluster according to claim 4, wherein the classifying all the pixel points in the step S33 is specifically as follows:
and when the Euclidean distance between the pixel point and the characteristic vector of the second clustering center a is greater than that between the pixel point and the characteristic vector of the second clustering center B, classifying the pixel point as a first cluster A, otherwise, classifying the pixel point as a first cluster B.
6. The method for detecting defects of a liquid crystal display based on single-pixel feature cluster building cluster according to claim 5, wherein the filtering process in S34 specifically comprises:
calculating characteristic vector Euclidean distances between all pixel points in the first cluster A and the second cluster center a, and calculating and obtaining a characteristic vector Euclidean distance mean value dAThe characteristic vector Euclidean distance between the first cluster center a and the second cluster center a is larger than j x dAThe pixel points of (a) are deleted from the first cluster a and added to the second cluster C, where j is a constant term.
7. The method for detecting the defects of the liquid crystal display based on the single-pixel feature cluster established cluster is characterized in that the step of judging whether the defects possibly exist according to whether the second cluster C is generated or not and the number of pixels contained in the second cluster C is specifically as follows:
when a second cluster C is generated and the number of pixel points in the second cluster C is more than 5, judging that a defect possibly exists;
when the second cluster C is not generated, whether the difference of the pixel point numbers of the first cluster A and the first cluster B is larger than 1/3 of the total pixel point number of the image is judged, and if the difference is larger than 1/3, the defect is judged to exist.
8. The method for detecting defects of a liquid crystal display based on single-pixel feature cluster building cluster according to claim 7, wherein the step S35 specifically comprises:
under the condition that a second cluster C appears and the number of pixel points in the second cluster C is more than 5, calculating whether the coordinate distribution of the pixel points in the second cluster C is discrete or not; under the condition that the second cluster C does not appear, selecting a cluster with a small number of pixel points in the first cluster A and the first cluster B, defining the cluster as a cluster Q, and calculating whether the pixel coordinate distribution of the pixel points in the cluster Q is discrete or not; and if the pixel point coordinates are distributed in a discrete manner, judging that no defect exists, and if the pixel point coordinates are distributed in an independently polymerizable region, judging that the defect occurs.
9. The method for detecting the defects of the liquid crystal display based on the single-pixel feature cluster building cluster of claim 8, wherein whether the coordinate distribution of the pixel points is discrete is specifically as follows:
setting a pixel point coordinate distribution distance threshold d, wherein the distance threshold
Figure FDA0003306469930000041
Wherein IwRepresenting the pixel width, I, of an imagehIndicating that the image pixel is high; sequentially traversing the pixel points in the cluster Q or the second cluster C, and calculating the coordinate distribution distance value d of every two pixel points in the cluster Q or the second cluster CPIf d isPD is less than or equal to d, the two pixel points are the coordinate cluster set of the similar pixel points, and the total number N of the newly clustered coordinate distribution clusters is obtainedd
Presetting a third threshold value T, wherein T is k NtWhere k is a constant term, NtThe total number of pixel points of the cluster Q or the second cluster C is NdWhen the number of the pixels in the cluster Q is larger than or equal to T, the pixel point coordinate distribution of the second cluster C is considered to be discrete, and the pixel point coordinate distribution is judged to be free of defects; otherwise, the coordinate distribution is considered to be in the independently polymerizable region, and the defect is judged.
10. An electronic device comprising a memory and a processor;
the memory stores computer-executable instructions;
the processor executes the computer-executable instructions stored in the memory, so that the processor executes the liquid crystal display defect detection method based on clustering of single-pixel features according to any one of claims 1 to 9.
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