CN117912404A - Boundary determination method of lamp bead effective pixel point applied to LED display screen - Google Patents

Boundary determination method of lamp bead effective pixel point applied to LED display screen Download PDF

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Publication number
CN117912404A
CN117912404A CN202410303030.3A CN202410303030A CN117912404A CN 117912404 A CN117912404 A CN 117912404A CN 202410303030 A CN202410303030 A CN 202410303030A CN 117912404 A CN117912404 A CN 117912404A
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China
Prior art keywords
pixel point
pixel
point
value
lamp bead
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CN202410303030.3A
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CN117912404B (en
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章琦杰
周强
蓝明华
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Hangzhou Hikvision Digital Technology Co Ltd
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Hangzhou Hikvision Digital Technology Co Ltd
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    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/22—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources
    • G09G3/30—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels
    • G09G3/32—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/2007—Display of intermediate tones
    • G09G3/2074—Display of intermediate tones using sub-pixels
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/02—Improving the quality of display appearance
    • G09G2320/029—Improving the quality of display appearance by monitoring one or more pixels in the display panel, e.g. by monitoring a fixed reference pixel
    • G09G2320/0295—Improving the quality of display appearance by monitoring one or more pixels in the display panel, e.g. by monitoring a fixed reference pixel by monitoring each display pixel
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/06—Adjustment of display parameters
    • G09G2320/0693—Calibration of display systems

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Control Of Indicators Other Than Cathode Ray Tubes (AREA)

Abstract

The embodiment of the application provides a boundary determination method of a lamp bead effective pixel point applied to an LED display screen. The method comprises the following steps: acquiring a target image when a lamp bead in a display screen is lighted, wherein the lamp bead comprises a first lamp bead and a second lamp bead which are adjacent in a target direction; determining a central pixel point of a first lamp bead and a central pixel point of a second lamp bead on a target image, wherein the central pixel point and the central pixel point of the second lamp bead are used as a first pixel point and a second pixel point; searching a pixel point with the pixel value smaller than the first threshold value as a third pixel point; determining a pixel point with the largest pixel value and a pixel point with the smallest pixel value as a fourth pixel point and a fifth pixel point; calculating the standard change rate of the pixel points on the third connecting line of the fourth pixel point and the fifth pixel point in the image coordinate system; and searching a pixel point with the absolute value of the difference value between the pixel value change rate and the standard change rate in the target direction smaller than the second threshold value on the third connecting line as a boundary pixel point of the first lamp bead. The efficiency of confirming the effective pixel point boundary of lamp pearl is improved.

Description

Boundary determination method of lamp bead effective pixel point applied to LED display screen
Technical Field
The application relates to the technical field of display control and image processing, in particular to a boundary determination method of a lamp bead effective pixel point applied to an LED display screen.
Background
The display screen correction system is used for correcting the display effect of the display screen, and the screen imaging quality of the display screen is closely related to the correction effect. When the display effect of the display screen is corrected, the number of effective pixel points of the lamp bead imaging is judged to be particularly critical, the imaging of light emitted by each lamp bead on an image is required to show the effects that the center is bright and the periphery is dark, the boundaries between adjacent lamp beads are clear, the imaging quality of the lamp beads can be influenced due to the fact that the effective pixel points of the lamp bead imaging are too much or too little, the correction effect is influenced, and the boundaries of the effective pixel points of the lamp bead are usually required to be judged firstly when the number of the effective pixel points of the lamp bead imaging is determined. At present, in the actual correction process, the judgment of the number of the effective pixel points of the lamp bead imaging depends on personnel experience, and the boundary of the effective pixel points of the lamp bead is judged according to human eyes, so that whether the number of the effective pixel points of the lamp bead imaging meets the corrected image requirement or not is determined, and the mode efficiency of determining the boundary of the effective pixel points of the lamp bead is lower.
Disclosure of Invention
The embodiment of the application aims to provide a boundary determining method of a lamp bead effective pixel point applied to an LED display screen, so as to improve the efficiency of determining the boundary of the lamp bead effective pixel point. The specific technical scheme is as follows:
the embodiment of the application provides a boundary determination method of a lamp bead effective pixel point, which comprises the following steps:
Acquiring a target image when a lamp bead in a display screen is lighted, wherein the lamp bead comprises a first lamp bead and a second lamp bead which are adjacent in a target direction; wherein the target direction is a horizontal direction and/or a vertical direction;
Determining a central pixel point of the first lamp bead on the target image as a first pixel point, and determining a central pixel point of the second lamp bead as a second pixel point;
Searching a pixel point with a pixel value smaller than a first threshold value on a first connecting line of the first pixel point and the second pixel point in an image coordinate system as a third pixel point;
Determining a pixel point with the largest pixel value as a fourth pixel point and a pixel point with the smallest pixel value as a fifth pixel point on a second connecting line of the first pixel point and the third pixel point in an image coordinate system;
calculating the standard change rate of the pixel points on the third connecting line of the fourth pixel point and the fifth pixel point in the image coordinate system; the standard change rate is used for representing the average value of the change rate of the pixel value of each pixel point positioned on the third connecting line, and the change rate of the pixel value is the change rate of the pixel value of the pixel point in the airspace;
and searching a pixel point with the absolute value of the difference value between the pixel value change rate in the target direction and the standard change rate smaller than a second threshold value on the third connecting line as a boundary pixel point of the first lamp bead.
In a possible embodiment, the calculating a standard rate of change of the pixel points located on the third line of the fourth pixel point and the fifth pixel point in the image coordinate system includes:
And taking the slope of a fourth connecting line of the fourth pixel point and the fifth pixel point at a corresponding point in a first pixel point distance-pixel value coordinate system as a standard change rate, wherein the first pixel point distance is the distance between the pixel point on the third connecting line and the first pixel point in the target direction.
In a possible embodiment, the searching for a pixel point, where an absolute value of a difference between the rate of change of the pixel value in the target direction and the standard rate of change is smaller than a second threshold, as a boundary pixel point of the first light bead includes:
And determining the pixel points on the third connecting line to be used as boundary pixel points of the first lamp beads when the pixel points are ordered from large to small according to the distance from the corresponding point of the pixel points in the first pixel point distance-pixel value coordinate system to the fourth connecting line.
In a possible embodiment, the beads are distributed in an array on the display screen, and the beads in each row and each column are aligned;
searching a pixel point with a pixel value smaller than a first threshold value on a first connecting line of the first pixel point and the second pixel point in an image coordinate system as a third pixel point, wherein the method comprises the following steps:
and determining a central pixel point positioned on a first connecting line of the first pixel point and the second pixel point in the image coordinate system as a third pixel point.
In one possible embodiment, the beads are distributed in an array on the display screen, and at least two rows or columns of beads are not aligned;
searching a pixel point with a pixel value smaller than a first threshold value on a first connecting line of the first pixel point and the second pixel point in an image coordinate system as a third pixel point, wherein the method comprises the following steps:
Acquiring a pixel value change curve in a second pixel point distance-pixel value coordinate system; the second pixel point distance is the distance between the first pixel point and the first pixel point on a first connecting line of the first pixel point and the second pixel point in an image coordinate system in the target direction;
And determining a first minimum value point which is started by a point corresponding to the first pixel point and is distant from the second pixel point in the forward direction on the pixel value change curve, and taking the pixel point corresponding to the point as a third pixel point.
In one possible embodiment, the method further comprises:
If the target direction is a horizontal direction, determining an effective pixel point of the first lamp bead in the horizontal direction according to the distance between the boundary pixel point and the first pixel point in the horizontal direction;
If the target direction is a vertical direction, determining an effective pixel point of the first lamp bead in the vertical direction according to the distance between the boundary pixel point and the first pixel point in the vertical direction.
The embodiment of the application also provides a boundary determination method of the lamp bead effective pixel point applied to the LED display screen, which comprises the following steps:
Obtaining a target image when a lamp bead in an LED display screen is lighted, wherein the lamp bead comprises a first lamp bead and a second lamp bead which are adjacent in a target direction; wherein the target direction is a horizontal direction and/or a vertical direction;
Determining a central pixel point of the first lamp bead on the target image as a first pixel point, and determining a central pixel point of the second lamp bead as a second pixel point;
Searching a pixel point with a pixel value smaller than a first threshold value on a first connecting line of the first pixel point and the second pixel point in an image coordinate system as a third pixel point;
Determining a pixel point with the largest pixel value as a fourth pixel point and a pixel point with the smallest pixel value as a fifth pixel point on a second connecting line of the first pixel point and the third pixel point in an image coordinate system;
calculating the standard change rate of the pixel points on the third connecting line of the fourth pixel point and the fifth pixel point in the image coordinate system; the standard change rate is used for representing the average value of the change rate of the pixel value of each pixel point positioned on the third connecting line, and the change rate of the pixel value is the change rate of the pixel value of the pixel point in the airspace;
and searching a pixel point with the absolute value of the difference value between the pixel value change rate in the target direction and the standard change rate smaller than a second threshold value on the third connecting line as a boundary pixel point of the first lamp bead.
The embodiment of the application also provides a device for determining the boundary of the effective pixel point of the lamp bead, which comprises the following steps:
The device comprises a target image acquisition module, a display screen and a display module, wherein the target image acquisition module is used for acquiring a target image when a lamp bead in the display screen is lighted, and the lamp bead comprises a first lamp bead and a second lamp bead which are adjacent in a target direction; wherein the target direction is a horizontal direction and/or a vertical direction;
The central pixel point determining module is used for determining a central pixel point of the first lamp bead on the target image as a first pixel point, and determining a central pixel point of the second lamp bead as a second pixel point;
A third pixel point searching module, configured to search, on a first line between the first pixel point and the second pixel point in an image coordinate system, a pixel point with a pixel value smaller than a first threshold value as a third pixel point;
A fourth pixel point determining module, configured to determine, on a second connection line between the first pixel point and the third pixel point in the image coordinate system, a pixel point with a maximum pixel value as a fourth pixel point, and determine, as a fifth pixel point, a pixel point with a minimum pixel value;
A standard change rate calculation module, configured to calculate a standard change rate of a pixel point located on a third line of the fourth pixel point and the fifth pixel point in an image coordinate system; the standard change rate is used for representing the average value of the change rate of the pixel value of each pixel point positioned on the third connecting line, and the change rate of the pixel value is the change rate of the pixel value of the pixel point in the airspace;
And the boundary pixel point searching module is used for searching the pixel points, on the third connecting line, of which the absolute value of the difference value between the pixel value change rate in the target direction and the standard change rate is smaller than a second threshold value, and the pixel points are used as the boundary pixel points of the first lamp beads.
In one possible embodiment, the standard rate of change statistics module calculates a standard rate of change of pixel points located on a third line of the fourth pixel point and the fifth pixel point in the image coordinate system, including:
And taking the slope of a fourth connecting line of the fourth pixel point and the fifth pixel point at a corresponding point in a first pixel point distance-pixel value coordinate system as a standard change rate, wherein the first pixel point distance is the distance between the pixel point on the third connecting line and the first pixel point in the target direction.
In a possible embodiment, the boundary pixel point searching module searches for a pixel point, where an absolute value of a difference between the pixel value change rate in the target direction and the standard change rate is smaller than a second threshold, as the boundary pixel point of the first light bead, including:
And determining the pixel points on the third connecting line to be used as boundary pixel points of the first lamp beads when the pixel points are ordered from large to small according to the distance from the corresponding point of the pixel points in the first pixel point distance-pixel value coordinate system to the fourth connecting line.
In a possible embodiment, the beads are distributed in an array on the display screen, and the beads in each row and each column are aligned;
The third pixel point searching module searches a pixel point with a pixel value smaller than a first threshold value on a first connection line of the first pixel point and the second pixel point in an image coordinate system, and is used as a third pixel point, and comprises:
and determining a central pixel point positioned on a first connecting line of the first pixel point and the second pixel point in the image coordinate system as a third pixel point.
In one possible embodiment, the beads are distributed in an array on the display screen, and at least two rows or columns of beads are not aligned;
The third pixel point searching module searches a pixel point with a pixel value smaller than a first threshold value on a first connection line of the first pixel point and the second pixel point in an image coordinate system, and is used as a third pixel point, and comprises:
Acquiring a pixel value change curve in a second pixel point distance-pixel value coordinate system; the second pixel point distance is the distance between the first pixel point and the first pixel point on a first connecting line of the first pixel point and the second pixel point in an image coordinate system in the target direction;
And determining a first minimum value point which is started by a point corresponding to the first pixel point and is distant from the second pixel point in the forward direction on the pixel value change curve, and taking the pixel point corresponding to the point as a third pixel point.
In one possible embodiment, the apparatus further comprises:
The effective pixel point determining module is used for determining an effective pixel point of the first lamp bead in the horizontal direction according to the distance between the boundary pixel point and the first pixel point in the horizontal direction if the target direction is the horizontal direction;
If the target direction is a vertical direction, determining an effective pixel point of the first lamp bead in the vertical direction according to the distance between the boundary pixel point and the first pixel point in the vertical direction.
The embodiment of the application also provides electronic equipment, which comprises:
A memory for storing a computer program;
and the processor is used for realizing any one of the above boundary determination methods of the lamp bead effective pixel points or the boundary determination method of the lamp bead effective pixel points applied to the LED display screen when executing the program stored in the memory.
The embodiment of the application also provides a computer readable storage medium, wherein a computer program is stored in the computer readable storage medium, and the computer program realizes the method for determining the boundary of the effective pixel point of the lamp bead or the method for determining the boundary of the effective pixel point of the lamp bead applied to the LED display screen when being executed by a processor.
The embodiment of the application also provides a computer program product containing instructions, which when run on a computer, causes the computer to execute the method for determining the boundary of the effective pixel point of the lamp bead or the method for determining the boundary of the effective pixel point of the lamp bead applied to the LED display screen.
The embodiment of the application has the beneficial effects that:
According to the boundary determining method applied to the lamp bead effective pixel point of the display screen, a target image when the lamp bead is lighted in the display screen can be obtained, the lamp bead comprises a first lamp bead and a second lamp bead which are adjacent in the target direction, the central pixel point of the first lamp bead is determined on the target image and used as a first pixel point, the central pixel point of the second lamp bead is determined, the first pixel point can be regarded as the brightest pixel point imaged by the first lamp bead, the second pixel point can be regarded as the brightest pixel point imaged by the second lamp bead, the pixel point with the pixel value smaller than a first threshold value is found on a first connecting line of the first pixel point and the second pixel point and used as a third pixel point, the pixel value of the third pixel point is sufficiently small, the first pixel point and the third pixel point can be determined on a second connecting line of the first pixel point and the third pixel point, the maximum pixel value can be determined on a second connecting line of the first pixel point and the third pixel point, the fourth pixel point can be regarded as the boundary point and the fifth pixel point can be determined on a fifth pixel point and the fourth pixel point. The standard change rate can represent the average value of the change rate of the pixel values of the pixel points positioned on the third connecting line, namely the standard change rate can represent the average value of the light attenuation rate of the pixel points positioned on the third connecting line, so that the speed of the change rate of the pixel values of the pixel points can be judged through the difference value of the standard change rate and the change rate of the pixel values of the pixel points positioned on the third connecting line in the target direction, namely the speed of the light attenuation of the pixel points is judged, and further whether the pixel points are effective pixel points for bead imaging is judged.
Because the light bead in the display screen can be regarded as a point light source, the intensity of light emitted by the point light source is inversely proportional to the square of the distance, and the intensity of light emitted by other light beads or noise such as an external light source can be influenced by the intensity of light during the imaging of the light bead, the influence of the noise on the intensity of light can be generally regarded as uniform change, therefore, the stronger the light of a pixel point which is closer to the center of the light bead is in the imaging of the light bead, and the faster the light attenuation rate of the pixel point which is closer to the center of the light bead is, at this time, the light attenuation rate of the pixel point can be regarded as being caused by the light change of the light emitted by the light bead, and the slower the light attenuation rate of the pixel point is also caused by the light emitted by the light bead, at this time, the light attenuation rate of the pixel point can be possibly caused by noise, and the light attenuation of the pixel point can be regarded as being less in the light change relation with the light emitted by the light bead itself. Because of the influence of noise factors, the pixel value of the pixel far from the center of the lamp bead, that is, the light intensity is high, so if only the pixel value of the pixel is used to judge whether the pixel is a valid pixel, the judgment result may be inaccurate. Therefore, the judgment of the effective pixel point can be performed through the pixel value change rate of the pixel point, namely, the light attenuation rate of the pixel point, when the pixel value change rate of the pixel point is larger than the standard change rate, the light attenuation of the pixel point is faster, the pixel point can be regarded as the effective pixel point of the first lamp bead imaging, when the pixel value change rate of the pixel point is smaller than the standard change rate, the light attenuation of the pixel point is slower, the pixel point can be regarded as the ineffective pixel point of the first lamp bead imaging, and therefore, when the pixel value change rate of the pixel point is more approximate to the standard change rate, the pixel point is more likely to be located between the effective pixel point and the ineffective pixel point, and the pixel point can be regarded as the limit between the effective pixel point and the ineffective pixel point. Therefore, the pixel point with the absolute value of the difference value between the pixel value change rate and the standard change rate in the pixel points on the third connection line being smaller than the second threshold value can be used as the boundary pixel point of the first lamp bead, so that the boundary of the effective pixel point of the first lamp bead is obtained, and compared with the mode of manually determining the boundary of the effective pixel point of the lamp bead, the efficiency of determining the boundary of the effective pixel point of the lamp bead is improved. The method for manually determining the boundary of the effective pixel point of the lamp bead depends on experience, but the experience of people is limited, and the method for manually determining the boundary of the effective pixel point of the lamp bead cannot be used for all scenes, so that a certain error exists in the boundary of the effective pixel point of the lamp bead manually determined under part of scenes.
Of course, it is not necessary for any one product or method of practicing the application to achieve all of the advantages set forth above at the same time.
Drawings
In order to more clearly illustrate the embodiments of the application or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the application, and other embodiments may be obtained according to these drawings to those skilled in the art.
Fig. 1 is a schematic flow chart of a method for determining a boundary of an effective pixel point of a lamp bead according to an embodiment of the present application;
FIG. 2a is a schematic diagram of a target image according to an embodiment of the present application;
FIG. 2b is another schematic diagram of a target image according to an embodiment of the present application;
FIG. 3a is a schematic diagram illustrating the positioning of a lamp bead according to an embodiment of the present application;
FIG. 3b is a schematic diagram of coordinates of a pixel according to an embodiment of the present application;
FIG. 4a is a schematic diagram of a pixel value variation curve according to an embodiment of the present application;
FIG. 4b is a schematic diagram of another variation curve of pixel values according to an embodiment of the present application;
FIG. 4c is a schematic diagram of a pixel value variation curve according to an embodiment of the present application;
FIG. 5a is a schematic flow chart of traversing a pixel according to an embodiment of the present application;
FIG. 5b is a schematic diagram of a pixel value variation curve according to an embodiment of the present application;
FIG. 5c is a schematic diagram of a pixel value variation curve according to an embodiment of the present application;
FIG. 6 is a schematic diagram of a device for determining a boundary of an effective pixel of a light bulb according to the present application;
Fig. 7 is a schematic structural diagram of an electronic device according to the present application.
Detailed Description
The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. Based on the embodiments of the present application, all other embodiments obtained by the person skilled in the art based on the present application are included in the scope of protection of the present application.
In order to more clearly describe the method for determining the boundary of the valid pixel point of the light bead applied to the LED display screen, the following description will be given by way of example of possible application scenarios of the method for determining the boundary of the valid pixel point of the light bead applied to the LED display screen, it is to be understood that the following examples are only possible application scenarios of the method for determining the boundary of the valid pixel point of the light bead applied to the LED display screen, and in other possible embodiments, the method for determining the boundary of the valid pixel point of the light bead applied to the LED display screen can be applied to other possible application scenarios, and the following examples do not limit the method.
The LED display screen is composed of tens of thousands to hundreds of thousands of LED pixel points which are uniformly arranged, different colors of LED pixel points can be manufactured by utilizing different materials, and various information display screens such as characters, graphics, images, animation, quotations, videos, video signals and the like can be displayed by controlling the display mode of the LEDs. To ensure the screen imaging quality of the LED display screen, correction of the display effect of the LED display screen is generally required. At present, in the correction process of the display effect of the LED display screen, the judgment of the number of the effective pixel points of the lamp bead imaging depends on personnel experience, and the boundary of the effective pixel points of the lamp bead is judged according to human eyes, so that whether the number of the effective pixel points of the lamp bead imaging accords with the corrected image requirement is determined, and the mode efficiency of determining the boundary of the effective pixel points of the lamp bead is lower.
Based on this, the application provides a method for determining the boundary of the effective pixel point of the lamp bead, as shown in fig. 1, specifically, the method may include the following steps:
S101, obtaining a target image when a lamp bead in a display screen is lighted, wherein the lamp bead comprises a first lamp bead and a second lamp bead which are adjacent in a target direction.
Wherein the target direction is a horizontal direction and/or a vertical direction.
S102, determining a central pixel point of a first lamp bead on the target image as a first pixel point, and determining a central pixel point of a second lamp bead as a second pixel point.
S103, searching a pixel point with a pixel value smaller than a first threshold value on a first connecting line of the first pixel point and the second pixel point in the image coordinate system as a third pixel point.
S104, determining a pixel with the largest pixel value as a fourth pixel and determining a pixel with the smallest pixel value as a fifth pixel on a second connecting line of the first pixel and the third pixel in the image coordinate system.
S105, calculating the standard change rate of the pixel points on the third connecting line of the fourth pixel point and the fifth pixel point in the image coordinate system.
The standard change rate is used for representing the average value of the change rate of the pixel value of each pixel point on the third connecting line, and the change rate of the pixel value is the change rate of the pixel value of the pixel point in the airspace.
And S106, on the third connecting line, searching a pixel point with the absolute value of the difference value between the pixel value change rate and the standard change rate in the target direction smaller than the second threshold value as a boundary pixel point of the first lamp bead.
By applying the embodiment of the application, the target image when the lamp beads in the display screen are lighted can be obtained, the lamp beads comprise the first lamp beads and the second lamp beads which are adjacent in the target direction, the central pixel point of the first lamp beads is determined on the target image and is used as a first pixel point, the central pixel point of the second lamp beads is determined and is used as a second pixel point, the first pixel point can be regarded as the brightest pixel point of the first lamp bead imaging, the second pixel point can be regarded as the brightest pixel point of the second lamp bead imaging, the pixel point with the pixel value smaller than the first threshold value is found on a first connecting line of the first pixel point and the second pixel point and is used as a third pixel point, so that the pixel value of the third pixel point is small enough, the pixel point with the largest pixel value can be determined and is used as a fourth pixel point on a second connecting line of the first pixel point and the third pixel point in an image coordinate system, and the pixel point with the fifth pixel point can be determined and is used as a fifth pixel point in the coordinate system, and the fifth pixel point can be located on the fifth pixel point and the coordinate system. The standard change rate can represent the average value of the change rate of the pixel values of the pixel points positioned on the third connecting line, namely the standard change rate can represent the average value of the light attenuation rate of the pixel points positioned on the third connecting line, so that the speed of the change rate of the pixel values of the pixel points can be judged through the difference value of the standard change rate and the change rate of the pixel values of the pixel points positioned on the third connecting line in the target direction, namely the speed of the light attenuation of the pixel points is judged, and further whether the pixel points are effective pixel points for bead imaging is judged.
Because the light bead in the LED display screen can be regarded as a point light source, the intensity of light emitted by the point light source is inversely proportional to the square of the distance, and the intensity of light emitted by the light bead during imaging can be influenced by noise such as light emitted by other light beads or an external light source, the influence of the noise on the intensity of light can be generally regarded as uniform change, therefore, the stronger the light of a pixel point which is closer to the center of the light bead is in the imaging of the light bead, and the faster the light attenuation rate of the pixel point which is closer to the center of the light bead is, at this time, the light attenuation rate of the pixel point can be regarded as being caused by the light change of the light emitted by the light bead, and the slower the light attenuation rate of the pixel point is also caused by the light emitted by the light bead, at this time, the light attenuation rate of the pixel point can be caused by the noise, and the light change relation with the light emitted by the light bead is smaller, therefore the light attenuation of the pixel point can be regarded as an ineffective pixel point when the light bead is imaged. Because of the influence of noise factors, the pixel value of the pixel far from the center of the lamp bead, that is, the light intensity is high, so if only the pixel value of the pixel is used to judge whether the pixel is a valid pixel, the judgment result may be inaccurate. Therefore, the judgment of the effective pixel point can be performed through the pixel value change rate of the pixel point, namely, the light attenuation rate of the pixel point, when the pixel value change rate of the pixel point is larger than the standard change rate, the light attenuation of the pixel point is faster, the pixel point can be regarded as the effective pixel point of the first lamp bead imaging, when the pixel value change rate of the pixel point is smaller than the standard change rate, the light attenuation of the pixel point is slower, the pixel point can be regarded as the ineffective pixel point of the first lamp bead imaging, and therefore, when the pixel value change rate of the pixel point is more approximate to the standard change rate, the pixel point is more likely to be located between the effective pixel point and the ineffective pixel point, and the pixel point can be regarded as the limit between the effective pixel point and the ineffective pixel point. Therefore, the pixel point with the absolute value of the difference value between the pixel value change rate and the standard change rate in the pixel points on the third connection line being smaller than the second threshold value can be used as the boundary pixel point of the first lamp bead, so that the boundary of the effective pixel point of the first lamp bead is obtained, and compared with the mode of manually determining the boundary of the effective pixel point of the lamp bead, the efficiency of determining the boundary of the effective pixel point of the lamp bead is improved. The method for manually determining the boundary of the effective pixel point of the lamp bead depends on experience, but the experience of people is limited, and the method for manually determining the boundary of the effective pixel point of the lamp bead cannot be used for all scenes, so that a certain error exists in the boundary of the effective pixel point of the lamp bead manually determined under part of scenes.
On the other hand, compared with the scheme of establishing a model to determine the boundary of the effective pixel point of the lamp bead, the method for determining the boundary of the effective pixel point of the lamp bead provided by the application can determine the boundary of the effective pixel point of the lamp bead without knowing various probability density function models and cumulative distribution function models, and greatly reduces the calculated amount of determining the boundary of the effective pixel point of the lamp bead while improving the efficiency of determining the boundary of the effective pixel point of the lamp bead.
The foregoing S101 to S106 will be described below, respectively, in which:
In S101, the method for determining the boundary of the effective pixel point of the lamp bead provided by the application can be applied to various display screens such as an LED display screen, an LCD display screen, an OLED display screen, and the like, and will be exemplified below by the LED display screen.
The target image can be obtained under the condition that all the lamp beads on the LED display screen are lighted, or can be obtained when the lamp beads in a certain area on the LED display screen are lighted and the lamp beads in the area are not lighted.
For the distribution of the beads on the LED display screen, in one possible embodiment, the beads are distributed in an array on the display screen, and the beads in each row and each column are aligned, and in this embodiment, the obtained target image may be as shown in fig. 2 a. In another possible embodiment, the beads are distributed in an array on the display screen, and at least two rows or columns of beads are not aligned, and in this embodiment, the acquired target image may be as shown in fig. 2 b. The application does not limit the distribution mode of the lamp beads on the display screen.
The target direction refers to a horizontal direction and/or a vertical direction, wherein the horizontal direction refers to a direction parallel to the pixel rows of the LED display screen, and the vertical direction refers to a direction perpendicular to the pixel rows of the LED display screen. And if the target direction is the horizontal direction or the vertical direction, executing S101-S105 aiming at the target direction to obtain the boundary pixel point of the first lamp bead in the target direction. If the target direction is the horizontal direction and the vertical direction, S101-S105 are executed respectively for the horizontal direction and the vertical direction, so as to obtain a boundary pixel point of the first lamp bead in the horizontal direction and a boundary pixel point of the first lamp bead in the vertical direction.
For two different target directions, namely, the horizontal direction and the vertical direction, the implementation manners of the method for determining the boundary of the effective pixel point of the lamp bead provided by the application are the same, so that the method for determining the boundary of the effective pixel point of the lamp bead provided by the application will be specifically described by taking the target direction as the horizontal direction.
In S102, the arrangement coordinates of each lamp bead in the target image and the coordinates of the central pixel point of the lamp bead corresponding to each lamp bead under the image coordinate system of the target image may be obtained through a lamp bead positioning algorithm. The arrangement coordinates of the lamp beads in the target image are used for representing the rows and columns of the lamp beads distributed in the target image, and the arrangement coordinates of the lamp beads in the target image are marked as N row and col, wherein row represents a row and col represents a column. If the target image is shown in fig. 2a, a schematic view of the bead positioning obtained by the bead positioning algorithm may be shown in fig. 3 a. The coordinates of the center pixel P corresponding to the lamp beads N [ row ] [ col ] in the image coordinate system of the target image can be marked as P { N [ row ] [ col ]. X, N [ row ] [ col ]. Y }.
For the coordinates of the pixel point in the image coordinate system of the target image, the pixel point in the image has a certain width and height, but the values of the width and the height are small, so the width and the height of the pixel point are negligible. Illustratively, as shown in fig. 3b, with the upper left corner of the image as the origin, the horizontal right as the X-axis, and the vertical down as the Y-axis, the coordinates of the darkened pixel point in fig. 3b are (4, 2).
The first bead may refer to any one of the beads in the target image, and the second bead is a bead adjacent to the first bead in a horizontal direction or a vertical direction. For convenience of description, the beads will be expressed in terms of arrangement coordinates of the beads, that is, nx y represents the beads located in the x-th row and y-th column. If the first bead is N row and the second bead is adjacent to the first bead in the horizontal direction, the second bead may be represented as N row and col+1 or N row and col-1; if the first bead is N row and the second bead is adjacent to the first bead in the vertical direction, the second bead may be N row+1 col or N row-1 col. Hereinafter, the first bead is N row, and the second bead is N row, and the target direction is horizontal.
The first lamp bead is N [ row ] [ col ], the central pixel point of the first lamp bead, namely the first pixel point is P { N [ row ] [ col ]. X, N [ row ] [ col ]. Y }; the second light bead is N [ row ] [ col+1], and the center pixel point of the second light bead, namely the second pixel point, is P 2 { N [ row ] [ col+1]. X, N [ row ] [ col+1]. Y }.
In S103, the pixel value refers to a value that may represent luminance information at a pixel point, and specifically, the pixel value may refer to a gray value, a luminance value, or the like. Hereinafter, a boundary determining method of a lamp bead effective pixel point provided by the application will be exemplarily described by taking a pixel value as an example and using a gray value as an expression. And searching for a pixel with a pixel value smaller than a first threshold value from all the pixel points on a first connection line of the first pixel point and the second pixel point in the image coordinate system as a third pixel point. The first threshold may be set to any value of 1,5, 10, etc. Only one pixel point with the found pixel value smaller than the first threshold value may be found, and at this time, the pixel point may be directly used as the third pixel point. The number of the pixels with the pixel value smaller than the first threshold may be plural, in this case, the pixel with the smallest pixel value among the pixels with the pixel value smaller than the first threshold may be used as the third pixel, or the pixels with the pixel value smaller than the first threshold may be arranged in order of the pixel values from small to large, and any one of the pixels with the number of the pixels preset in the arrangement may be used as the third pixel, where the preset number may be set to any value such as 3, 5, etc.
Because the pixel point with smaller pixel value on the first connection line of the first pixel point and the second pixel point in the image coordinate system is determined as the third pixel point through the setting of the first threshold value, if the setting of the first threshold value is overlarge, more pixel points with smaller pixel value than the first threshold value can be possibly caused, and the pixel point with smaller pixel value can not be determined from the searched pixel points more conveniently and accurately as the third pixel point; if the first threshold is set too small, it may result in that no pixel point with a pixel value smaller than the first threshold is found, so that the third pixel point cannot be determined. Therefore, the pixel point with smaller pixel value on the first connecting line of the first pixel point and the second pixel point in the image coordinate system can be directly determined as the third pixel point through the distribution of the lamp beads on the LED display screen and the luminous characteristics of the lamp beads.
For the aforesaid lamp pearl is array distribution on the display screen, and the condition that the lamp pearl of each row each column is aligned, confirm the mode of third pixel, include: and determining a central pixel point positioned on a first connecting line of the first pixel point and the second pixel point in the image coordinate system as a third pixel point.
Taking an LED display screen as an example, it may be understood that if the light beads are distributed in an array on the LED display screen, and the light beads in each row and each column are aligned, then the effect that the light emitted by the light beads is combined to form an image on the image, the center is bright and the periphery is dark, and the boundary between the adjacent light beads is clear, so that the pixel value of the center point of two adjacent light beads may be considered to be generally minimum, that is, the pixel value of the center pixel point may be considered to be minimum in each pixel point on the first line between the first pixel point and the second pixel point in the image coordinate system. The pixel value change curve of each pixel point located on the first line of the first pixel point and the second pixel point in the image coordinate system may be as shown in fig. 4 a. Therefore, the center pixel point on the first line of the first pixel point and the second pixel point in the image coordinate system can be used as the third pixel point, so that the pixel point with smaller pixel value on the first line of the first pixel point and the second pixel point in the image coordinate system can be determined as the third pixel point.
If the target direction is the horizontal direction, as described above, the first pixel is P { N [ row ] [ col ]. X, N [ row ] [ col ]. Y }, the second pixel is P 2 { N [ row ] [ col+1]. X, N [ row ] [ col+1]. Y }, and if the third pixel is P center, the coordinate of the third pixel in the X-axis direction is P center. X= (N [ row ] [ col ]. X+N [ row ] [ col+1]. X)/2. As shown in fig. 4b, since the first and second beads are adjacent and aligned in the horizontal direction, it can be considered that the center pixel of the first bead and the center pixel of the second bead are aligned in the horizontal direction, that is, the coordinates of the first and second pixels in the Y-axis direction are equal, and the coordinates P center. Y=n [ row ] [ col ]. Y=n [ row ] [ col+1]. Y ] of the third pixel in the Y-axis direction are P center { (N row ] [ col ] [ x+n [ row ] [ col+1]. X)/2, N [ row ] [ col ]. Y }, with the center pixel on the first line as the third pixel.
If the target direction is vertical, the first pixel is P { N [ row ] [ col ]. X, N [ row ] [ col ]. Y }, the second pixel is P 2 { N [ row+1] [ col ]. X, N [ row+1] [ col ]. Y }, and if the third pixel is P center, the coordinate of the third pixel in the Y-axis direction is P center. Y= (N [ row ] [ col ]. Y+N [ row+1] [ col ]. Y)/2. Since the first and second beads are adjacent and aligned in the vertical direction, the center pixel of the first bead and the center pixel of the second bead may be considered to be aligned in the vertical direction, that is, the coordinates of the first pixel and the second pixel in the X-axis direction are equal, the coordinates P center. X=n [ row ] [ col ] = N [ row+1] [ col ]. X, and the coordinates of the third pixel are P center { N [ row ] [ col ]. X, (N [ row ] [ col ]. Y+n [ row+1] [ col ]. Y)/2 }.
In this embodiment, since the beads are distributed in an array on the display screen, and the beads in each row and each column are aligned, the effect that the light emitted by the beads should appear bright in the center and dark in the periphery when the light is imaged on the image, and the boundary between the adjacent beads is clear can be considered as the pixel value of the center point of two adjacent beads is generally minimum, that is, the pixel value of the center pixel is minimum in each pixel on the first line of the first pixel and the second pixel in the image coordinate system, so that the third pixel can be directly determined, the searching and comparing in a plurality of pixels are not needed, the calculation amount for determining the third pixel is greatly reduced, the efficiency for determining the third pixel is improved, the calculation amount for determining the boundary of the effective pixel of the beads is greatly reduced, and the efficiency for determining the boundary of the effective pixel of the bead is improved.
For the situation that the lamp beads are distributed in an array on the display screen and at least two rows or two columns of lamp beads are not aligned; the method for determining the third pixel point comprises the following steps: acquiring a pixel value change curve in a second pixel point distance-pixel value coordinate system; the second pixel point distance is the distance between the first pixel point and the first pixel point on the first connecting line of the first pixel point and the second pixel point in the image coordinate system in the target direction; and determining a first minimum value point which is started by a point corresponding to the first pixel point and is along the second pixel point from the forward direction on the pixel value change curve, and taking the pixel point corresponding to the point as a third pixel point.
The distance between the pixel point a and the pixel point B is taken as a unit pixel, and since the width and the height of the pixel point are one unit pixel, the distance between the pixel point a and the pixel point B can be understood as: the number of pixels spaced between pixel a and pixel B. Taking an LED display screen as an example, if the beads are distributed in an array on the LED display screen, and at least two rows or two columns of beads are not aligned, the target image is shown in fig. 2b, and referring to fig. 2b, the brightness between the first and second beads adjacent in two horizontal directions will be interfered by the brightness of the beads in the adjacent rows. At this time, as shown in fig. 4c, the pixel value change curve in the second pixel distance-pixel value coordinate system may be that the horizontal axis of the coordinate system is the second pixel distance, and the vertical axis is the gray value, that is, the pixel value, in units of pixel points. The second pixel point distance refers to the distance between the first pixel point and the pixel point on the first line of the first pixel point and the second pixel point in the image coordinate system in the target direction. Referring to fig. 4c, if a pixel point with a smaller pixel value on a first line between a first pixel point and a second pixel point in an image coordinate system needs to be determined and used as a third pixel point, a center pixel point on the first line cannot be directly used as the third pixel point, but a pixel point with a minimum value from a point corresponding to the first pixel point to be along a forward direction of the second pixel point, namely, a pixel point corresponding to a first inflection point is used as the third pixel point on a pixel value change curve.
In this embodiment, if the light beads are distributed in an array on the display screen and at least two rows or two columns of the light beads are not aligned, a pixel value change curve of each pixel point on a first line of a first pixel point and a second pixel point in the image coordinate system can be obtained; the pixel point corresponding to the first minimum value point of the pixel value change curve is determined and used as the third pixel point, so that the third pixel point can be directly determined, searching and comparing in a plurality of pixel points are not needed, the calculated amount for determining the third pixel point is greatly reduced, the efficiency for determining the third pixel point is improved, the calculated amount for determining the boundary of the effective pixel point of the lamp bead is greatly reduced, and the efficiency for determining the boundary of the effective pixel point of the lamp bead is improved.
In S104, when determining the fourth pixel point and the fifth pixel point, all the pixel points on the second connection line of the first pixel point and the third pixel point in the image coordinate system may be traversed, to obtain the pixel values corresponding to the pixel points on the second connection line, determine the pixel point with the largest pixel value as the fourth pixel point, and determine the pixel point with the smallest pixel value as the fifth pixel point. The flow chart of the traversal may be as shown in fig. 5 a. In the target image [ x, y ], taking the coordinates P { N [ row ] [ col ]. X, N [ row ] [ col ]. Y } of the first pixel point as initial coordinates, judging whether the x coordinate of the pixel point of the current extracted pixel value is larger than the x coordinate of the third pixel point, if so, namely, the x coordinate of the pixel point of the current extracted pixel value is larger than the x coordinate of the third pixel point, ending the traversal flow; if not, that is, the x coordinate of the pixel point of the current extracted pixel value is not greater than the x coordinate of the third pixel point, adding 1 to the x coordinate of the pixel point of the current extracted pixel value, and continuing to extract the pixel value Data [ i ] of the next pixel point in the target image [ x, y ].
If a plurality of pixel points with the same pixel value and the maximum pixel value are arranged on the second connection line, the pixel point with the maximum pixel value closest to the third pixel point is taken as a fourth pixel point. It can be understood that the intensity of the light emitted by the lamp beads normally attenuates with the increase of the propagation distance, so that only one pixel point with the maximum pixel value exists, and if a plurality of pixel points with the maximum pixel value exist at the same time, the influence of the light emission of other lamp beads can be considered to cause the fluctuation of the pixel value of the pixel point. The pixel point with the largest pixel value is not appeared between the pixel point with the largest pixel value closest to the third pixel point and the third pixel point, so that the pixel point with the largest pixel value closest to the third pixel point and the pixel point between the third pixel point are not influenced or less influenced by the light emission of other lamp beads, and therefore the pixel point with the largest pixel value closest to the third pixel point can be used as a fourth pixel point to reduce the interference of the light emission of other lamp beads on the determined boundary pixel point.
If a plurality of pixel points with the same pixel value and the minimum pixel value are arranged on the second connection line, the pixel point with the minimum pixel value closest to the first pixel point is taken as a fifth pixel point. Similarly, in normal cases, only one pixel point with the minimum pixel value exists, and if a plurality of pixel points with the minimum pixel value exist at the same time, the pixel points can be regarded as that the pixel value of the pixel points fluctuates due to the luminous influence of other lamp beads. And the pixel point with the minimum pixel value is not appeared between the pixel point with the minimum pixel value closest to the first pixel point and the first pixel point, the pixel value of the pixel point with the minimum pixel value closest to the first pixel point and the pixel point between the first pixel point can be considered to be not influenced or less influenced by the light emission of other lamp beads, so the pixel point with the minimum pixel value closest to the first pixel point can be used as a fifth pixel point to reduce the interference of the light emission of other lamp beads on the determined boundary pixel point.
In combination with the effect that the light emitted by the beads should show bright center and dark periphery and clear boundary between adjacent beads, the pixel value of the central pixel point of the beads can be considered to be the largest, so in one possible embodiment, the central pixel point of the first bead, that is, the first pixel point, can be determined as the pixel point with the largest pixel value on the second line, that is, the first pixel point is taken as the fourth pixel point.
The third pixel point may also be determined as the pixel point with the smallest pixel value on the second line, that is, the third pixel point is taken as the fifth pixel point. As an example, as in S103, when the light beads are distributed in an array on the display screen and the light beads of each row and each column are aligned, it may be considered that the pixel value of the center pixel is the smallest among the pixel points located on the first line of the first pixel point and the second pixel point in the image coordinate system, and thus the center pixel on the first line may be regarded as the third pixel point. Then, the third pixel point may be determined as the pixel point with the smallest pixel value on the second line, i.e., the third pixel point is the fifth pixel point.
When the light beads are distributed in an array on the display screen and at least two rows or two columns of the light beads are not aligned, a first minimum value point which is started by a point corresponding to the first pixel point and is along the forward direction of the distance between the second pixel point and the pixel value in the pixel value change curve in the second pixel point distance-pixel value coordinate system can be determined, and the pixel point corresponding to the minimum value point can be regarded as a point with the minimum pixel value on the first connecting line and is regarded as a third pixel point. Then, the third pixel point may be determined as the pixel point with the smallest pixel value on the second line, i.e., the third pixel point is the fifth pixel point.
In S105, the pixel value change rate herein refers to a change rate of the pixel value in the spatial domain, that is: the amount of change in pixel values in the case of changing the unit distance in the image coordinate system. The rate of change of the pixel value in the target direction is: in the case where the image coordinate system is changed by a unit distance in the target direction, for example, assuming that the coordinates of a pixel point a in the image coordinate system are (x, y), the pixel value of the pixel point a is I (x, y), and the target direction is the horizontal direction, and the unit distance is Δ, in the case where the image coordinate system is changed by a unit distance in the target direction, the pixel value should be changed to the pixel value at the coordinates of (x+Δ, y), denoted as I (x+Δ, y), and thus the rate of change of the pixel value in the target direction at the pixel point a is I (x+Δ, y) -I (x, y). When the unit distance Δ is regarded as 1, in the case where the image coordinate system changes the unit distance in the target direction, the pixel value should be changed to the pixel value at the coordinates (x+1, y), that is, the pixel value of the pixel point B adjacent to the pixel point a, denoted as I (x+1, y), and therefore the rate of change of the pixel value in the target direction at the pixel point a is I (x+1, y) -I (x, y), that is, the rate of change of the pixel value in the target direction at the pixel point a is: the difference between the pixel value of pixel a and the pixel value of the adjacent pixel B.
The standard rate of change is used to represent the average of the rates of change of the pixel values of the respective pixel points located on the third lines of the fourth pixel point and the fifth pixel point in the image coordinate system. The standard change rate is obtained by calculating an average value of the change rates of the pixel values of all the pixel points located on the third line.
In one possible embodiment, the slope of the fourth line of the two pixels of the fourth pixel and the fifth pixel at the corresponding point in the first pixel distance-pixel value coordinate system may be used as the standard change rate, where the first pixel distance is the distance between the pixel on the third line and the first pixel in the target direction.
The distance between the pixel point on the third connection line and the first pixel point in the horizontal direction can be regarded as i in the traversing process of fig. 5a. The pixel value change curve of each pixel point located on the second connection line extracted according to the above-mentioned traversing method shown in fig. 5a may be as shown in fig. 5b, and since the fourth pixel point and the fifth pixel point are also pixel points located on the second connection line, the point between the maximum pixel value point and the minimum pixel value point marked in fig. 5b, that is, the point corresponding to the pixel point on the third connection line, the curve between the maximum pixel value point and the minimum pixel value point in fig. 5b may be regarded as the pixel value change curve of each pixel point located on the third connection line. Referring to fig. 5b, the horizontal axis of the coordinate system is the first pixel distance, and the vertical axis is the gray value, i.e., the pixel value, in units of pixels.
It will be appreciated that two points are arbitrarily selected on the pixel value variation curve shown in fig. 5b, and assuming that point 1 is (X 1,f（x1)), point 2 is (X 2,f（x2)), the distances between point 1 and point 2 in the X-axis direction are equally divided into n parts, each of which isI.e.When n is sufficiently large,/>Small enough, the tangential slope of point 1, i.e. the rate of change of pixel value of the pixel point corresponding to point 1 is/>Point/>The change rate of the pixel value of the corresponding pixel point is… …, And so on, dot/>The change rate of the pixel value of the corresponding pixel point is/>. The average value of the pixel value change rates of the pixel points corresponding to the n points is/>Due to/>，. Obviously, k' is the slope of the line between the point 1 and the point 2, and the slope of the line between the point 1 and the point 2 can be regarded as the average value of the pixel value change rates of the pixel points corresponding to all the points between the point 1 and the point 2. Therefore, the slope of the fourth line may be regarded as the average value of the pixel value change rates of the pixel points located on the third line, i.e., equivalent to the standard change rate.
Referring to fig. 5b, the target direction is the horizontal direction, the X-axis of the coordinate system in fig. 5b represents the distance between the pixel point located on the third connection line and the first pixel point in the horizontal direction, i.e., the first pixel point distance, and the Y-axis represents the pixel value corresponding to the pixel point located on the third connection line, so that the coordinate system shown in fig. 5b may be referred to as the first pixel point distance-pixel value coordinate system.
The sitting of the pixel point with the largest pixel value on the second connecting line, namely the fourth pixel point, in the first pixel point distance-pixel value coordinate system is marked as Pmax (pmax.x, pmax.y), the sitting of the pixel point with the smallest pixel value on the second connecting line, namely the fifth pixel point, in the first pixel point distance-pixel value coordinate system is marked as Pmin (pmin.x, pmin.y), and the slope of the fourth connecting line, namely the standard change rate, can be calculated by the following formula (1):
；
where k represents a standard change rate, pmax.y represents an ordinate of a point corresponding to the fourth pixel point in the first pixel point distance-pixel value coordinate system, pmin.y represents an ordinate of a point corresponding to the fifth pixel point in the first pixel point distance-pixel value coordinate system, pmax.x represents an abscissa of a point corresponding to the fourth pixel point in the first pixel point distance-pixel value coordinate system, and pmin.x represents an abscissa of a point corresponding to the fifth pixel point in the first pixel point distance-pixel value coordinate system.
By adopting the embodiment, the slope of the fourth connecting line of the two pixels of the fourth pixel point and the fifth pixel point, which are positioned at the corresponding point in the first pixel point distance-pixel value coordinate system, can be directly used as the standard change rate in the third connecting line of the fourth pixel point and the fifth pixel point in the image coordinate system, so that the standard change rate can be determined more simply, the calculated amount for determining the boundary of the effective pixel point of the lamp bead is reduced, and the efficiency for determining the boundary of the effective pixel point of the lamp bead is improved.
In S105, if the target direction is the horizontal direction, among the pixel points located on the third line, a pixel point having an absolute value of a difference between the pixel value change rate in the horizontal direction and the standard change rate smaller than the second threshold value is searched as a boundary pixel point of the first bead. The second threshold may be set to any value of 0.1, 0.2, 0.5, etc. The speed of the change rate of the pixel value of each pixel point can be judged through the difference value of the standard change rate and the change rate of the pixel value of each pixel point positioned on the third connecting line, so that the light intensity at each pixel point can be further judged. When the change rate of the pixel value of the pixel point is larger than the standard change rate, the light of the pixel point is faster and stronger, and can be regarded as an effective pixel point of the first lamp bead imaging, when the change rate of the pixel value of the pixel point is smaller than the standard change rate, the light of the pixel point is slower and the light of the pixel point is weaker, and can be regarded as an ineffective pixel point of the first lamp bead imaging, so that when the change rate of the pixel value of the pixel point is more approximate to the standard change rate, the pixel point is more likely to be positioned between the effective pixel point and the ineffective pixel point, and can be regarded as a limit between the effective pixel point and the ineffective pixel point.
In one possible embodiment, it is determined that the pixel points on the third connection line are located at the first preset number of bits of pixel points as the boundary pixel points of the first light bead when the pixel points are ordered from large to small according to the distance from the corresponding point in the first pixel point distance-pixel value coordinate system to the fourth connection line. The first pixel point distance is the distance between the pixel point on the third connecting line of the fourth pixel point and the fifth pixel point in the image coordinate system and the first pixel point in the target direction.
Specifically, the distance from the corresponding point of the pixel point on the third connecting line to the fourth connecting line in the first pixel point distance-pixel value coordinate system can be obtained, the pixel points on the third connecting line are ordered according to the sequence from the large distance to the small distance, and the pixel points with the first preset number of bits in the ordering are determined to be used as the boundary pixel points of the first lamp beads. Taking the target direction as the horizontal direction as an example, referring to fig. 5c, the coordinates of the corresponding point of the pixel point on the third connection line in the first pixel point distance-pixel value coordinate system are denoted as (i, data [ i ]), where i represents the distance between the pixel point on the third connection line and the first pixel point in the horizontal direction, that is, the first pixel point distance, and Data [ i ] represents the pixel value corresponding to the pixel point on the third connection line and the first pixel point in the horizontal direction, that is, the distance i between the pixel point and the first pixel point. The slope k of the fourth line, i.e. the straight line L, can be calculated by the foregoing formula (1), and the equation of the straight line L is y=kx+b=k (x-pmin.x) +pmin.y, where pmin.x represents the abscissa of the point corresponding to the fifth pixel point in the first pixel point distance-pixel value coordinate system, and pmin.y represents the ordinate of the point corresponding to the fifth pixel point in the first pixel point distance-pixel value coordinate system. The distance from the corresponding point of the pixel point located on the third connecting line to the fourth connecting line in the first pixel point distance-pixel value coordinate system can be calculated by the following formula (2):
；
Wherein d [ i ] is the distance from the pixel point on the third connecting line to the fourth connecting line in the first pixel point distance-pixel value coordinate system, k is the slope of the straight line L, data [ i ] is the pixel value corresponding to the pixel point on the third connecting line with the first pixel point having the distance i in the horizontal direction, and b is the intercept of the straight line L.
Sequencing all the pixel points from large to small according to the distance calculated by the formula (2), and taking the pixel points positioned at the preset number of bits as boundary pixel points of the first lamp beads. The larger the distance from the corresponding point of the pixel point to the fourth connecting line in the first pixel point distance-pixel value coordinate system, the closer the pixel value change rate of the pixel point in the horizontal direction is to the standard change rate, and the more likely the pixel point is the boundary pixel point of the first lamp bead. The preset number may be set to 1, that is, a pixel point having a pixel value change rate closest to the standard change rate in the horizontal direction, which is the largest distance from the corresponding point in the first pixel point distance-pixel value coordinate system to the fourth line, is used as the boundary pixel point of the first lamp bead.
The preset number can also be set to other values, such as 2, 3, etc., and the pixel point of the preset number of bits in the sequence can be used as the boundary pixel point of the first lamp bead. For example, considering the interference of the light emitted by the light beads around the first light beads on the light emission imaging of the first light beads, the pixel value of the pixel point at the position of the first light beads in the target image may be larger or smaller than the brightness of the light emitted by the first light beads which are not interfered, and the interference suffered at different positions is different. That is, the obtained pixel value change curve shown in fig. 5b may deviate from the pixel value change curve obtained when the first lamp bead is not interfered and emits light and images, and accordingly, the pixel point corresponding to the point with the largest distance from the fourth connecting line in the first pixel point distance-pixel value coordinate system is not necessarily the boundary pixel point of the first lamp bead. Therefore, the pixel point corresponding to the point with the largest distance from the fourth connecting line can be used as the candidate pixel point, and the pixel point obtained after the candidate pixel point is shifted leftwards or rightwards by the preset unit is used as the boundary pixel point of the first lamp bead. The preset unit refers to the number of pixels, i.e. the pixels on the left or right side of the candidate pixel are regarded as boundary pixels of the first lamp bead, and the pixels are shifted to the left or right by one pixel.
Referring to fig. 5c, it is obvious that the adjacent pixels have smaller variation between the corresponding point in the first pixel distance-pixel value coordinate system and the fourth line distance, so that when the pixels are sorted from large to small according to the distance calculated by the formula (2), the adjacent pixels are also closer. Therefore, the offset of the candidate pixel may be regarded as the offset of the distance calculated according to the formula (2), and the boundary pixel of the first bead is obtained after the offset of the candidate pixel, that is, the pixel of the 2 nd or 3 rd preset number of bits in the sequence is used as the boundary pixel of the first bead.
If the target direction is the vertical direction, the pixel point obtained after the candidate pixel point is shifted upwards or downwards by a preset unit is required to be used as the boundary pixel point of the first lamp bead.
In one possible implementation manner, the preset number may be defaulted to 1, and the pixel point with the largest distance from the corresponding point to the fourth line in the first pixel point distance-pixel value coordinate system is taken as the boundary pixel point of the first lamp bead.
By adopting the embodiment, according to the pixel value change curve of each pixel point on the third connection line of the fourth pixel point and the fifth pixel point in the image coordinate system, the turning point of smooth attenuation of the pixel value of the lamp bead can be determined through a three-point method, namely, the boundary pixel point of the first lamp bead is determined.
In a possible embodiment, the effective pixel point of the first lamp bead may be determined according to the determined boundary pixel point. If the target direction is the horizontal direction, determining an effective pixel point of the first lamp bead in the horizontal direction according to the distance between the boundary pixel point and the first pixel point in the horizontal direction; if the target direction is the vertical direction, determining an effective pixel point of the first lamp bead in the vertical direction according to the distance between the boundary pixel point and the first pixel point in the vertical direction.
Specifically, if the target direction is the horizontal direction, after the boundary pixel point is determined, the range of the effective pixel point of the first lamp bead in the horizontal direction can be determined according to the distance i between the boundary pixel point and the first pixel point in the horizontal direction, or the distance i between the boundary pixel point and the first pixel point in the horizontal direction can be used as the cutoff distance of the first lamp bead illumination imaging in the horizontal direction, and since the height and the width of the pixel point are one unit pixel, the distance i between the boundary pixel point and the central pixel point of the first lamp bead, i.e. the first pixel point in the horizontal direction, can be considered to be half the number of the pixel points occupied by the first lamp bead in the horizontal direction, and the number of the pixel points occupied by the horizontal width of the first lamp bead can be determined to be w=2i.
If the target direction is the vertical direction, after determining the boundary pixel point, the range of the effective pixel point of the first lamp bead in the vertical direction can be determined according to the distance i between the boundary pixel point and the first pixel point in the vertical direction, and the distance i between the boundary pixel point and the first pixel point in the vertical direction can be used as the cutoff distance of the first lamp bead illumination imaging in the vertical direction.
The effective pixel point of the first lamp bead can be determined through the boundary pixel point of the first lamp bead, the first lamp bead can be any lamp bead in the display screen, the effective pixel point of the first lamp bead can be determined, the lamp bead distribution on the display screen and the brightness of the lamp bead can be conveniently adjusted, and the display result of the display screen can be conveniently corrected.
The application also provides a method for determining the boundary of the effective pixel point of the lamp bead, which is applied to the LED display screen, and comprises the following steps:
Obtaining a target image when a lamp bead in an LED display screen is lighted, wherein the lamp bead comprises a first lamp bead and a second lamp bead which are adjacent in a target direction; wherein the target direction is a horizontal direction and/or a vertical direction;
Determining a central pixel point of a first lamp bead on a target image as a first pixel point, and determining a central pixel point of a second lamp bead as a second pixel point;
Searching a pixel point with a pixel value smaller than a first threshold value on a first connecting line of a first pixel point and a second pixel point in an image coordinate system as a third pixel point;
determining a pixel point with the largest pixel value as a fourth pixel point and a pixel point with the smallest pixel value as a fifth pixel point on a second connecting line of the first pixel point and the third pixel point in the image coordinate system;
calculating the standard change rate of the pixel points on the third connecting line of the fourth pixel point and the fifth pixel point in the image coordinate system; the standard change rate is used for representing the average value of the change rate of the pixel value of each pixel point positioned on the third connecting line, and the change rate of the pixel value is the change rate of the pixel value of the pixel point in the airspace;
And searching for a pixel point with the absolute value of the difference value between the pixel value change rate and the standard change rate in the target direction smaller than the second threshold value on the third connecting line as a boundary pixel point of the first lamp bead.
The specific implementation of the method for determining the boundary of the effective pixel point of the lamp bead applied to the LED display screen is the same as the specific implementation of the method for determining the boundary of the effective pixel point of the lamp bead, and will not be described herein.
The application also provides a device for determining the boundary of the effective pixel point of the lamp bead, as shown in fig. 6, the device comprises:
a target image obtaining module 601, configured to obtain a target image when a bead in a display screen is lit, where the bead includes a first bead and a second bead that are adjacent in a target direction; wherein the target direction is a horizontal direction and/or a vertical direction;
The central pixel point determining module 602 is configured to determine a central pixel point of a first lamp bead on the target image as a first pixel point, and determine a central pixel point of a second lamp bead as a second pixel point;
a third pixel searching module 603, configured to search, on a first line between the first pixel and the second pixel in the image coordinate system, a pixel having a pixel value smaller than a first threshold value as a third pixel;
A fourth pixel determining module 604, configured to determine, on a second connection line between the first pixel and the third pixel in the image coordinate system, a pixel with a maximum pixel value as a fourth pixel, and determine, as a fifth pixel, a pixel with a minimum pixel value;
A standard change rate calculation module 605, configured to calculate a standard change rate of a pixel point located on a third line of the fourth pixel point and the fifth pixel point in the image coordinate system; the standard change rate is used for representing the average value of the change rate of the pixel value of each pixel point positioned on the third connecting line, and the change rate of the pixel value is the change rate of the pixel value of the pixel point in the airspace;
The boundary pixel point searching module 606 is configured to search, on the third connection line, a pixel point having an absolute value of a difference between the rate of change of the pixel value in the target direction and the standard rate of change smaller than the second threshold value as a boundary pixel point of the first light bead.
In one possible embodiment, the standard rate of change statistics module calculates a standard rate of change of pixel points located on a third line of a fourth pixel point and a fifth pixel point in the image coordinate system, including:
And taking the slope of a fourth connecting line of the fourth pixel point and the fifth pixel point at the corresponding point in the first pixel point distance-pixel value coordinate system as a standard change rate, wherein the first pixel point distance is the distance between the pixel point on the third connecting line and the first pixel point in the target direction.
In one possible embodiment, the boundary pixel point searching module searches for a pixel point, where an absolute value of a difference between a change rate of a pixel value in the target direction and a standard change rate is smaller than a second threshold, as a boundary pixel point of the first light bead, including:
And determining the pixel points on the third connecting line as boundary pixel points of the first lamp beads when the pixel points are ordered from large to small according to the distance from the corresponding point of the pixel points in the first pixel point distance-pixel value coordinate system to the fourth connecting line.
In one possible embodiment, the beads are distributed in an array on the display screen, and the beads in each row and each column are aligned;
The third pixel point searching module searches a pixel point with a pixel value smaller than a first threshold value on a first connecting line of the first pixel point and the second pixel point in an image coordinate system, and is used as a third pixel point, and comprises:
and determining a central pixel point positioned on a first connecting line of the first pixel point and the second pixel point in the image coordinate system as a third pixel point.
In one possible embodiment, the beads are distributed in an array on the display screen, and at least two rows or columns of beads are not aligned;
The third pixel point searching module searches a pixel point with a pixel value smaller than a first threshold value on a first connecting line of the first pixel point and the second pixel point in an image coordinate system, and is used as a third pixel point, and comprises:
acquiring a pixel value change curve in a second pixel point distance-pixel value coordinate system; the second pixel point distance is the distance between the first pixel point and the first pixel point on the first connecting line of the first pixel point and the second pixel point in the image coordinate system in the target direction;
and determining a first minimum value point which is started by a point corresponding to the first pixel point and is along the second pixel point from the forward direction on the pixel value change curve, and taking the pixel point corresponding to the point as a third pixel point.
In one possible embodiment, the apparatus further comprises:
The effective pixel point determining module is used for determining the effective pixel point of the first lamp bead in the horizontal direction according to the distance between the boundary pixel point and the first pixel point in the horizontal direction if the target direction is the horizontal direction;
if the target direction is the vertical direction, determining an effective pixel point of the first lamp bead in the vertical direction according to the distance between the boundary pixel point and the first pixel point in the vertical direction.
The embodiment of the application also provides an electronic device, as shown in fig. 7, including:
a memory 701 for storing a computer program;
the processor 702 is configured to execute the program stored in the memory 701, and implement the following steps:
Acquiring a target image when a lamp bead in a display screen is lighted, wherein the lamp bead comprises a first lamp bead and a second lamp bead which are adjacent in a target direction; wherein the target direction is a horizontal direction and/or a vertical direction;
Determining a central pixel point of a first lamp bead on a target image as a first pixel point, and determining a central pixel point of a second lamp bead as a second pixel point;
Searching a pixel point with a pixel value smaller than a first threshold value on a first connecting line of a first pixel point and a second pixel point in an image coordinate system as a third pixel point;
determining a pixel point with the largest pixel value as a fourth pixel point and a pixel point with the smallest pixel value as a fifth pixel point on a second connecting line of the first pixel point and the third pixel point in the image coordinate system;
calculating the standard change rate of the pixel points on the third connecting line of the fourth pixel point and the fifth pixel point in the image coordinate system; the standard change rate is used for representing the average value of the change rate of the pixel value of each pixel point positioned on the third connecting line, and the change rate of the pixel value is the change rate of the pixel value of the pixel point in the airspace;
And searching for a pixel point with the absolute value of the difference value between the pixel value change rate and the standard change rate in the target direction smaller than the second threshold value on the third connecting line as a boundary pixel point of the first lamp bead.
And the electronic device may further comprise a communication bus and/or a communication interface, through which the processor 702, the communication interface, and the memory 701 communicate with each other.
The communication bus mentioned above for the electronic device may be a peripheral component interconnect standard (PERIPHERAL COMPONENT INTERCONNECT, PCI) bus or an extended industry standard architecture (Extended Industry StandardArchitecture, EISA) bus, etc. The communication bus may be classified as an address bus, a data bus, a control bus, or the like. For ease of illustration, the figures are shown with only one bold line, but not with only one bus or one type of bus.
The communication interface is used for communication between the electronic device and other devices.
The memory may include random access memory (Random Access Memory, RAM) or may include non-volatile memory (NVM), such as at least one disk memory. Optionally, the memory may also be at least one memory device located remotely from the aforementioned processor.
The processor may be a general-purpose processor, including a central processing unit (Central Processing Unit, CPU), a network processor (Network Processor, NP), etc.; but may also be a digital signal Processor (DIGITAL SIGNAL Processor, DSP), application SPECIFIC INTEGRATED Circuit (ASIC), field-Programmable gate array (Field-Programmable GATE ARRAY, FPGA) or other Programmable logic device, discrete gate or transistor logic device, discrete hardware components.
In yet another embodiment of the present application, there is also provided a computer readable storage medium having a computer program stored therein, the computer program when executed by a processor implementing the steps of the method for determining a boundary of an effective pixel point of any one of the above-mentioned light beads.
In yet another embodiment of the present application, a computer program product containing instructions that, when run on a computer, cause the computer to perform the method of determining a boundary of an effective pixel point of any of the above-described embodiments of the present application is also provided.
In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, produces a flow or function in accordance with embodiments of the present application, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. The computer instructions may be stored in or transmitted from one computer-readable storage medium to another, for example, by wired (e.g., coaxial cable, optical fiber, digital Subscriber Line (DSL)), or wireless (e.g., infrared, wireless, microwave, etc.). The computer readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that contains an integration of one or more available media. The usable medium may be a magnetic medium (e.g., floppy disk, hard disk, tape), an optical medium (e.g., DVD), or a Solid state disk (Solid STATE DISK, SSD), etc.
It is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
In this specification, each embodiment is described in a related manner, and identical and similar parts of each embodiment are all referred to each other, and each embodiment mainly describes differences from other embodiments. In particular, for the apparatus, electronic device, computer readable storage medium, and computer program product embodiments, the description is relatively simple, as relevant to the method embodiments being referred to in the section of the description of the method embodiments.
The foregoing description is only of the preferred embodiments of the present application and is not intended to limit the scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application are included in the protection scope of the present application.

Claims (10)

1. The method for determining the boundary of the effective pixel point of the lamp bead is characterized by comprising the following steps:
Acquiring a target image when a lamp bead in a display screen is lighted, wherein the lamp bead comprises a first lamp bead and a second lamp bead which are adjacent in a target direction; wherein the target direction is a horizontal direction and/or a vertical direction;
Determining a central pixel point of the first lamp bead on the target image as a first pixel point, and determining a central pixel point of the second lamp bead as a second pixel point;
Searching a pixel point with a pixel value smaller than a first threshold value on a first connecting line of the first pixel point and the second pixel point in an image coordinate system as a third pixel point;
Determining a pixel point with the largest pixel value as a fourth pixel point and a pixel point with the smallest pixel value as a fifth pixel point on a second connecting line of the first pixel point and the third pixel point in an image coordinate system;
calculating the standard change rate of the pixel points on the third connecting line of the fourth pixel point and the fifth pixel point in the image coordinate system; the standard change rate is used for representing the average value of the change rate of the pixel value of each pixel point positioned on the third connecting line, and the change rate of the pixel value is the change rate of the pixel value of the pixel point in the airspace;
and searching a pixel point with the absolute value of the difference value between the pixel value change rate in the target direction and the standard change rate smaller than a second threshold value on the third connecting line as a boundary pixel point of the first lamp bead.
2. The method of claim 1, wherein said calculating a standard rate of change of pixel points located on a third line of said fourth pixel point and said fifth pixel point in an image coordinate system comprises:
And taking the slope of a fourth connecting line of the fourth pixel point and the fifth pixel point at a corresponding point in a first pixel point distance-pixel value coordinate system as a standard change rate, wherein the first pixel point distance is the distance between the pixel point on the third connecting line and the first pixel point in the target direction.
3. The method according to claim 2, wherein the searching for a pixel point having an absolute value of a difference between a rate of change of the pixel value in the target direction and the standard rate of change smaller than a second threshold value as a boundary pixel point of the first bead includes:
And determining the pixel points on the third connecting line to be used as boundary pixel points of the first lamp beads when the pixel points are ordered from large to small according to the distance from the corresponding point of the pixel points in the first pixel point distance-pixel value coordinate system to the fourth connecting line.
4. The method of claim 1, wherein the beads are distributed in an array on the display screen, and the beads of each row and each column are aligned;
searching a pixel point with a pixel value smaller than a first threshold value on a first connecting line of the first pixel point and the second pixel point in an image coordinate system as a third pixel point, wherein the method comprises the following steps:
and determining a central pixel point positioned on a first connecting line of the first pixel point and the second pixel point in the image coordinate system as a third pixel point.
5. The method of claim 1, wherein the beads are distributed in an array on the display screen, and wherein at least two rows or columns of beads are not aligned;
searching a pixel point with a pixel value smaller than a first threshold value on a first connecting line of the first pixel point and the second pixel point in an image coordinate system as a third pixel point, wherein the method comprises the following steps:
Acquiring a pixel value change curve in a second pixel point distance-pixel value coordinate system; the second pixel point distance is the distance between the first pixel point and the first pixel point on a first connecting line of the first pixel point and the second pixel point in an image coordinate system in the target direction;
And determining a first minimum value point which is started by a point corresponding to the first pixel point and is distant from the second pixel point in the forward direction on the pixel value change curve, and taking the pixel point corresponding to the point as a third pixel point.
6. The method according to claim 1, wherein the method further comprises:
If the target direction is a horizontal direction, determining an effective pixel point of the first lamp bead in the horizontal direction according to the distance between the boundary pixel point and the first pixel point in the horizontal direction;
If the target direction is a vertical direction, determining an effective pixel point of the first lamp bead in the vertical direction according to the distance between the boundary pixel point and the first pixel point in the vertical direction.
7. The method for determining the boundary of the effective pixel point of the lamp bead applied to the LED display screen is characterized by comprising the following steps:
Obtaining a target image when a lamp bead in an LED display screen is lighted, wherein the lamp bead comprises a first lamp bead and a second lamp bead which are adjacent in a target direction; wherein the target direction is a horizontal direction and/or a vertical direction;
Determining a central pixel point of the first lamp bead on the target image as a first pixel point, and determining a central pixel point of the second lamp bead as a second pixel point;
Searching a pixel point with a pixel value smaller than a first threshold value on a first connecting line of the first pixel point and the second pixel point in an image coordinate system as a third pixel point;
Determining a pixel point with the largest pixel value as a fourth pixel point and a pixel point with the smallest pixel value as a fifth pixel point on a second connecting line of the first pixel point and the third pixel point in an image coordinate system;
calculating the standard change rate of the pixel points on the third connecting line of the fourth pixel point and the fifth pixel point in the image coordinate system; the standard change rate is used for representing the average value of the change rate of the pixel value of each pixel point positioned on the third connecting line, and the change rate of the pixel value is the change rate of the pixel value of the pixel point in the airspace;
and searching a pixel point with the absolute value of the difference value between the pixel value change rate in the target direction and the standard change rate smaller than a second threshold value on the third connecting line as a boundary pixel point of the first lamp bead.
8. An electronic device, comprising:
A memory for storing a computer program;
A processor for implementing the method of any one of claims 1-6 or 7 when executing a program stored on a memory.
9. A computer readable storage medium, characterized in that the computer readable storage medium has stored therein a computer program which, when executed by a processor, implements the method of any of claims 1-6 or 7.
10. A computer program product comprising a computer program which, when executed by a processor, implements the method according to any of claims 1-6 or 7.
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