CN115953981B

CN115953981B - Special-shaped plane screen lamp point positioning method and brightness information obtaining method

Info

Publication number: CN115953981B
Application number: CN202310171276.5A
Authority: CN
Inventors: 苗静; 郑喜凤; 毛新越; 郭贵新; 徐子程; 曹慧
Original assignee: Changchun Cedar Electronics Technology Co Ltd
Current assignee: Changchun Cedar Electronics Technology Co Ltd
Priority date: 2023-02-28
Filing date: 2023-02-28
Publication date: 2023-06-16
Anticipated expiration: 2043-02-28
Also published as: CN115953981A

Abstract

The invention provides a special-shaped plane screen lamp point positioning method and a brightness information obtaining method, relates to control of an indicating device for displaying variable information by a static method, and particularly relates to the field of display screen correction. The problems of time consumption, labor consumption and poor universality of the prior art are solved by adopting the traditional display screen correction technology to correct the display screens of the special-shaped plane screens with different shapes. According to the lamp point positioning method, the minimum circumscribed rectangle Dv of the outline of the special-shaped plane screen is drawn; calculating to obtain the barycenter coordinates of the theoretical lamp points; and carrying out coordinate correction on the centroid coordinates of the theoretical lamp points to obtain the centroid coordinates of the application lamp points. The LED flat screen detection device is mainly applied to the technical fields of production detection, installation and maintenance of LED flat screens with various shapes.

Description

Special-shaped plane screen lamp point positioning method and brightness information obtaining method

Technical Field

The invention relates to control of an indication device for displaying variable information by a static method, in particular to the field of display screen correction.

Background

The LED display screen is widely applied to commercial media, cultural performance, information transmission, news release and the like due to the advantages of bright color, wide dynamic range, high brightness, long service life and the like.

It is known to those skilled in the art that an LED display screen is formed by splicing individual LED display modules, and each LED display module has a plurality of LED light emitting dies, also called light spots, integrated thereon, and the LED light emitting dies are elements for emitting light. Due to the self-luminescence discreteness, performance attenuation and the like of the LED luminous tube cores, the brightness and/or chromaticity emitted by different LED luminous tube cores of the same specification are different under the condition of the same power input, and the phenomenon of uneven brightness and chromaticity of the LED display module and the LED display screen is caused. In order to improve the display uniformity of the LED display screen and enhance the viewing comfort of human eyes, an LED display screen correction technology appears.

The LED display screen correction technology can be divided into single module correction and whole screen correction; the single module correction means that one LED display module is corrected so that the brightness and/or chromaticity of each light point on the LED display module are consistent, the single module correction is generally used before the LED display modules are spliced into an LED display screen; the whole screen correction refers to that the whole LED display screen is regarded as a whole, and the whole LED display screen is corrected so that the brightness and/or chromaticity of each lamp point on the whole LED display screen are consistent, and the whole screen correction is generally used after the LED display modules are spliced into the LED display screen.

The whole screen correction aiming at the traditional LED display screen is mature, and the common method is as follows: firstly, shooting a specific image of an LED display screen through a camera for one or more times; then, positioning the lamp points of the screen image, and extracting optical information of each lamp point on the LED display screen in the shooting area; then, according to the optical information and the image of the whole screen, calculating to obtain a compensation coefficient (or called a correction coefficient) of each lamp point; and finally, the compensation coefficient (or called a correction coefficient) is sent to a control system, and the control system carries out differential adjustment on the brightness and/or chromaticity of each lamp point on the whole LED display screen so as to enable the brightness and/or chromaticity of each lamp point on the whole LED display screen to be consistent.

Along with the higher and higher personalized requirements of people on the LED display screen, more special-shaped LED plane screens (or special-shaped plane screens for short) appear, and the special-shaped LED plane screens still belong to the field of plane display screens, but in the whole shape, the traditional rectangle is not used, but more diversified shapes such as a circle, a trapezoid, a triangle and the like are adopted; the special-shaped LED plane screens with different shapes bring more visual impact to us and simultaneously bring new difficulties to the correction of the display screen.

At present, the correction technology of the LED display screen is developed aiming at the traditional rectangular screen, wherein the positioning extraction technology (namely the lamp point positioning technology) of the optical information of the LED pixel points is also a corresponding algorithm developed based on the rectangular shape. However, the special-shaped LED plane screen has difficulty in positioning and extracting the optical information of the LED pixel points due to the irregular shape; by adopting a traditional display screen correction technology, correcting the special-shaped LED plane screens with different shapes, and developing different algorithms to position and extract pixel point optical information of the special-shaped LED plane screens; therefore, the display screen correction technology is adopted to correct the display screen of the special-shaped LED flat panel with a plurality of different shapes, so that the time and the labor are consumed, and the universality is poor.

Therefore, a general, simple and easy lamp point positioning method suitable for the special-shaped LED flat panel (or the special-shaped flat panel for short) is needed.

Disclosure of Invention

The invention provides a special-shaped plane screen lamp point positioning method and a brightness information obtaining method, which solve the problems of time consumption, labor consumption and poor universality of the prior art that a traditional display screen correction technology is adopted to correct a plurality of special-shaped plane screens with different shapes.

The invention relates to a positioning method for a lamp point of a special-shaped plane screen, which comprises the following steps:

the method for positioning the special-shaped plane screen lamp points specifically comprises the following steps:

s1, setting a rectangular coordinate system taking pixels as a unit on a pure-color image of a special-shaped plane screen acquired in advance;

s2, drawing a minimum circumscribed rectangle Dv of the outline of the special-shaped plane screen in the rectangular coordinate system;

s3, calculating the coordinates of four vertexes of the minimum circumscribed rectangle Dv in the rectangular coordinate system, namely, the coordinates of the top left corner vertex LT are (xa, ya), the coordinates of the top right corner vertex RT are (xb, ya), the coordinates of the bottom left corner vertex LB are (xa, yc), and the coordinates of the bottom right corner vertex RB are (xb, yc);

s4, constructing a rectangular array in the minimum circumscribed rectangle Dv according to the four vertex coordinates, the preset number Hn of the horizontal longest row of lamp points and the preset number Vn of the longitudinal longest column of lamp points, wherein the rectangular array consists of Vn rows and Hn columns of uniformly arranged pixel points, the pixel points used for forming the rectangular array are theoretical lamp points, the theoretical lamp points at the four vertices of the rectangular array are overlapped with the four vertices of the minimum circumscribed rectangle Dv, and the centroid coordinates of each theoretical lamp point in the rectangular array and the centroid coordinate matrix S of all theoretical lamp points are obtained through calculation;

S5, calculating to obtain a light spot radius R according to the pre-acquired pure-color image of the special-shaped plane screen;

and S6, carrying out coordinate correction on the theoretical lamp points in the rectangular array, and calculating to obtain centroid coordinates and centroid coordinate matrixes of the application lamp points corresponding to the theoretical lamp points, thereby completing lamp point positioning.

Further, a preferred embodiment is provided, wherein the step S6 is specifically as follows:

s6.1, selecting a theoretical lamp point from the rectangular array, and calculating to obtain a theoretical light spot brightness value of the theoretical lamp point;

s6.2, traversing all adjacent pixels of the theoretical lamp points, and acquiring a theoretical facula brightness value of each adjacent pixel; the adjacent pixels are pixels which are contained in a rectangular range with the theoretical lamp point as the center and the side length of 2d, wherein R is more than or equal to d and less than or equal to 2R, and the unit is the pixel; the theoretical light spot brightness value is the gray value sum of all pixel points in a rectangular range with the side length of 2R by taking the theoretical light point or adjacent pixels as the center;

s6.3, comparing the theoretical facula brightness value of the theoretical lamp point with the theoretical facula brightness value of the adjacent pixels, and selecting according to the following conditions:

If the virtual light spot brightness values of all the adjacent pixels are not larger than the theoretical light spot brightness value of the theoretical light spot, the centroid coordinate of the theoretical light spot is the centroid coordinate of the application light spot corresponding to the theoretical light spot;

if the virtual light spot brightness value of the adjacent pixels is larger than the theoretical light spot brightness value of the theoretical light spot, the centroid coordinate of the adjacent pixels corresponding to the virtual light spot brightness value with the largest value is the centroid coordinate of the application light spot corresponding to the theoretical light spot;

s6.4, repeating the steps S6.1-S6.3 until all theoretical lamp points are subjected to coordinate correction, and obtaining the centroid coordinates and centroid coordinate matrixes of the corresponding application lamp points, so that the positioning of the special-shaped plane screen lamp points is completed.

Further, a preferred embodiment is provided, and the step S4 is specifically as follows:

s4.1, the rectangular array consists of Vn rows and Hn columns of uniformly arranged pixel points, the pixel points used for forming the rectangular array are theoretical lamp points, the theoretical lamp points of the ith row and the jth column in the rectangular array are S (i, j), wherein i is more than or equal to 1 and less than or equal to Vn, j is more than or equal to 1 and less than or equal to Hn, hn is the preset number of transverse longest row lamp points, and Vn is the preset number of longitudinal longest column lamp points Vn;

S4.2, uniformly distributing the rectangular arrays in the minimum circumscribed rectangle Dv;

the theoretical lamp point of the left upper corner vertex of the rectangular array is s (1, 1), coincides with the left upper corner vertex LT coordinate of the minimum circumscribed rectangle Dv, and has centroid coordinates of (xa, ya);

the theoretical lamp point of the top right corner vertex of the rectangular array is s (1, hn), coincides with the top right corner vertex RT coordinate of the minimum circumscribed rectangle Dv, and the barycenter coordinate is (xb, ya);

the theoretical lamp point of the left lower corner vertex of the rectangular array is s (Vn, 1), coincides with the left lower corner vertex LB coordinate of the minimum circumscribed rectangle Dv, and has centroid coordinates of (xa, yc);

the theoretical lamp point of the left lower corner vertex of the rectangular array is s (Vn, hn), coincides with the left lower corner vertex RB coordinate of the minimum circumscribed rectangle Dv, and the centroid coordinate is (xb, yc);

s4.3, the barycenter coordinates of the theoretical lamp points S (i, j) are as follows:

(xi,yj)=(xa+(xb-xa)/(Hn-1)×(j-1),ya+(yc-ya)/(Vn-1)×(i-1))。

s4.4, the centroid coordinate matrix S of the theoretical lamp points is expressed as:

。

further, a preferred embodiment is provided, wherein the value range of the spot radius R in the step S5 is [4,10 ], and the unit is a pixel.

Further, a preferred embodiment is provided, wherein the pre-acquired solid-color image of the shaped flat panel in step S1 is acquired by using an interlaced acquisition mode.

The invention also provides a method for obtaining the brightness information of the special-shaped flat screen, which has the following technical scheme:

the method for obtaining the brightness information of the special-shaped plane screen comprises the following steps:

ST1, performing lamp point correction on a pre-acquired pure-color image of the special-shaped plane screen by adopting the special-shaped plane screen lamp point positioning method, and obtaining centroid coordinates of an application lamp point of the special-shaped plane screen;

ST2, selecting an application lamp point of the special-shaped plane screen, and obtaining a spot brightness value of the application lamp point, wherein the spot brightness value is the gray value sum of all pixel points in a rectangular range with the centroid coordinates of the application lamp point as the center and the side length of 2R;

and ST3, repeating the step ST2 until the spot brightness values of all the application light points are obtained, wherein the brightness matrix L of the special-shaped plane screen is expressed as:

and L (i, j) is the spot brightness value of the application lamp point of the ith row and the jth column in the special-shaped plane screen, and the brightness matrix L is the brightness information of the special-shaped plane screen.

The invention also provides a method for acquiring the correction coefficient of the special-shaped flat screen, which has the following technical scheme:

the method for acquiring the correction coefficient of the special-shaped plane screen comprises the following steps of;

STE1, acquiring solid-color images of the special-shaped plane screen to obtain N acquired pictures T1-TN;

STE2, aiming at each acquired picture Ti, wherein i is more than or equal to 1 and less than or equal to N, performing the following treatment to obtain a brightness matrix LDi of an application lamp point corresponding to the acquired picture Ti

By adopting the special-shaped plane screen lamp point positioning method, lamp points are positioned on the special-shaped plane screen according to the acquired picture Ti, and a centroid coordinate matrix Zi of the application lamp points corresponding to the acquired picture Ti is obtained;

obtaining a brightness matrix LDi of an application lamp point corresponding to the acquired picture Ti according to the centroid coordinate matrix Zi;

STE3, calculating correction coefficients of the special-shaped plane screen according to all acquired pictures and the brightness matrix of the corresponding application lamp points.

The invention also provides an evaluation method of the display uniformity of the special-shaped flat screen, which has the following technical scheme:

the method for evaluating the display uniformity of the special-shaped flat screen comprises the following steps of;

STEP1, carrying out brightness correction on the special-shaped plane screen to obtain the special-shaped plane screen after brightness correction;

STEP2, performing solid-color image acquisition on the special-shaped plane screen after brightness correction to obtain N acquired pictures T1-TN;

STEP3, aiming at each acquired picture Ti, wherein i is more than or equal to 1 and less than or equal to N, and performing the following treatment to obtain a brightness matrix LDi of an application lamp point corresponding to the acquired picture Ti:

Adopting the special-shaped plane screen lamp point positioning method to position the lamp points of the special-shaped plane screen according to the acquired picture Ti, and obtaining a centroid coordinate matrix Zi of the application lamp points corresponding to the acquired picture Ti;

and STEP4, evaluating the display uniformity of the special-shaped plane screen according to all acquired pictures and the brightness matrix of the application lamp points corresponding to the acquired pictures.

The invention also provides a computer device, which has the following technical scheme:

a computer device, comprising: the processor is configured to execute the above-mentioned special-shaped flat screen lamp point positioning method, or execute the above-mentioned special-shaped flat screen brightness information obtaining method, or the above-mentioned special-shaped flat screen correction coefficient obtaining method, or the above-mentioned special-shaped flat screen display uniformity evaluating method by executing the executable instructions.

The invention also provides a computer storage medium, which has the following technical scheme:

a computer storage medium, in which a computer program is stored, and when the computer program runs, the method for positioning the abnormal flat screen lamp point is executed, or the method for obtaining brightness information of the abnormal flat screen is executed, or the method for obtaining correction coefficient of the abnormal flat screen is executed, or the method for evaluating display uniformity of the abnormal flat screen is executed.

The invention has the following beneficial effects:

1. the invention performs lamp point positioning by mapping the special-shaped plane screen into a rectangle, can perform whole-screen lamp point positioning on special-shaped plane screens with various shapes in a general way, and has good universality.

2. The lamp point positioning information obtained by the special-shaped plane screen lamp point positioning method can be used for carrying out whole screen correction or whole screen display uniformity evaluation, and compared with a method adopting the traditional LED display screen correction or evaluation, the method is simple, convenient, easy to implement, time-saving and labor-saving.

The special-shaped plane screen lamp point positioning method and the brightness information obtaining method are suitable for the technical fields of production detection, installation and maintenance of LED plane screens with various shapes.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic view of a trapezoid flat screen according to a preferred embodiment of the present invention;

FIG. 2 is a schematic view of a triangular flat screen in accordance with a preferred embodiment of the present invention;

FIG. 3 is a schematic view of a circular flat screen in accordance with a preferred embodiment of the present invention;

FIG. 4 is a schematic view of a rounded rectangular flat screen in accordance with a preferred embodiment of the present invention;

FIG. 5 is a diagram of a centroid traversal diagram 1 in accordance with a preferred embodiment of the invention;

fig. 6 is a diagram of a centroid traversal diagram 2 in accordance with a preferred embodiment of the invention.

Detailed Description

In order to make the technical solution and the advantages of the present invention more clear, the detailed description of the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

An embodiment one, referring to fig. 1 to fig. 6, illustrates a method for positioning a lamp point of a special-shaped flat screen according to the embodiment, which is specifically implemented as follows:

The method specifically comprises the following steps:

s5, calculating and obtaining a centroid radius R according to the pre-acquired solid-color image of the special-shaped plane screen;

S6, carrying out coordinate correction on the theoretical lamp points in the rectangular array, and calculating to obtain centroid coordinates and centroid coordinate matrixes of the application lamp points corresponding to the theoretical lamp points, so as to finish lamp point positioning; the method comprises the following steps:

Description of the present embodiment:

in this embodiment, the pre-collected solid-color image of the special-shaped flat panel generally refers to that the control system controls the special-shaped flat panel to fixedly display a solid-color picture, and then the camera shoots the solid-color picture; the solid color displayed is typically one of the three primary colors red, green and blue. There are many existing techniques for acquiring solid-color images of a shaped flat screen, one method is to display a certain solid color from all the light points of the shaped flat screen and then shoot the images; in another method, a part of light points on a special-shaped plane screen display a certain solid color, other light points do not emit light, and then an image is shot. Regarding the collection mode of interlaced columns, the method for collecting the pixel lighting chromaticity information of the LED display screen can be referred to in Chinese patent ZL 201010613815.9. For example, a collection mode (2×2 collection mode for short) of 2 rows and 2 columns is that on a display screen lamp lattice array, one lamp is turned on every second lamp in the transverse direction, and one lamp is turned on every second lamp in the longitudinal direction, so that the optical information of the whole screen can be obtained by increasing the collection times without enlarging the resolution of the camera and without reducing the collection area. Adopting a 2 multiplied by 2 acquisition mode, and acquiring 4 images aiming at each single primary color (one color in red, green and blue) to obtain images with all the lamps lighted; if three single primary color display screen images are to be acquired, 12 images are required to be acquired in total, and acquired image sequences P1-P12 can be obtained, wherein red light point information is contained in picture sequences P1-P4, green light point information is contained in picture sequences P5-P8, and blue light point information is contained in picture sequences P9-P12.

In the present embodiment, since the graphics of the solid-color image is composed of a plurality of pixels (or pixel points), the rectangular coordinate system constructed on the solid-color image indicates the size of the graphics by the number of pixels included in the graphics. For example, the light points on the special-shaped plane screen (or called special-shaped LED plane screen) form a high-brightness area, called a light spot for short, with a single high-brightness area being separated from each other on the collected solid-color image, the light spot is a rectangular area composed of a plurality of pixels, and if the light spot is composed of 5 rows and 5 columns of pixels, the side of the rectangle formed by the outline of the light spot is composed of 5 pixels, and the side length of the side of the rectangle is 5 pixels.

In this embodiment, the method for drawing the smallest circumscribed rectangle belongs to the prior art, for example, a rounded rectangle display screen, the upper and lower bottom edges of the rounded rectangle are parallel and have equal length, and the left and right edges of the rounded rectangle are circular arc edges, so that when drawing the smallest circumscribed rectangle, the upper and lower bottom edges of the rounded rectangle may be rectangular long edges, and a line segment formed by cutting the tangent line of the left and right circular arc edges of the rounded rectangle by the upper and lower bottom edges is rectangular short edges. Each side of the minimum bounding rectangle is composed of one pixel in the acquired solid-color image, and the number of pixels composing one side is used to represent the side length, for example, the side length is 5, and the side is composed of 5 pixels.

In this embodiment, the number Hn of the horizontal longest row of light spots and the number Vn of the vertical longest column of light spots respectively represent a rectangular array formed by light spots in the minimum circumscribed rectangle, the number Hn of the light spots, and the number Vn of the light spots. The number of the lamp points Hn of the horizontal longest row and the number of the lamp points Vn of the vertical longest column are obtained through pre-calculation. The special-shaped plane screen is formed by splicing a plurality of modules (namely LED display modules), and after each LED display module is designed, the number of the lamp points on the special-shaped plane screen is fixed and known, so that after the special-shaped plane screen is assembled and spliced, the number of the actual lamp points on the transverse or longitudinal direction of the screen can be determined, and only the lamp points on a transverse certain row or a longitudinal certain column of the screen are accumulated. The number Hn of the transverse longest row of lamps and the number Vn of the longitudinal longest column of lamps are related to the actual number of lamps of the special-shaped plane screen and the acquisition mode. For example, for a special-shaped plane screen, when surface display acquisition (i.e. no interlacing is performed), in a rectangular area after image mapping is performed by a camera, the number Hn of light points in the horizontal longest row is chn, and the number Vn of light points in the vertical longest column is cvn; if the same special-shaped plane screen is displayed and acquired in an interlaced column-separating mode, and mod rows and mod columns are assumed to be acquired, the number Hn of the lamp points in the transverse longest row is chn/mod and the number Vn of the lamp points in the longitudinal longest column is cvn/mod on each acquired picture, and mod×mod pictures are required to be acquired for each primary color.

In this embodiment, the centroid coordinates of the light points are used to represent the positions of the light points on the special-shaped LED flat panel (or the special-shaped flat panel for short). On the collected solid-color image, the light spot is displayed as a light spot, the light spot is a rectangular area composed of pixels, and if the rectangular area is composed of 5 rows and 5 columns of pixels, the pixels arranged on the 3 rd row and the 3 rd column in the rectangular area are central pixels of the light spot, and the coordinates of the central pixels of the light spot on the solid-color image can represent the position of the light spot on the special-shaped LED plane screen, namely the centroid coordinates of the light spot.

In this embodiment, the centroid radius R of the light points, which is also referred to as the spot radius, is a light emitting area of each light point on the collected solid-color image. On a special-shaped LED plane screen, the centroid radius R of all the lamp points is the same. On the collected solid-color image, the light spot is displayed as a light spot, the light spot is a rectangular area composed of pixels, the side length of the rectangular area is 2R, and the centroid radius R is 5 pixels on the assumption that the side length of the rectangular area is composed of 10 pixels. The typical centroid radius R ranges from 4 to 10 pixels. A method for obtaining a centroid radius R according to an acquired solid-color image, which belongs to the prior art; in the prior art, some methods for obtaining the centroid radius R need to obtain the centroid coordinates first, and some methods for obtaining the centroid radius R do not need to obtain the centroid coordinates first, and the latter method is adopted in this embodiment. For example, the size of the centroid radius R can be determined by observing the collected solid-color image by human eyes; or the size of the centroid radius R may be obtained by a binary method. The approximate step of obtaining the size of the centroid radius R by the binary method is as follows: firstly, filtering an acquired solid-color picture to remove noise values of low gray scale and high gray scale; then, setting a threshold value to carry out binarization processing, and only reserving each light point region in the processed image; and then, extracting the outline, and extracting the outline circle of the light spot, wherein the radius of the circle is the centroid radius R. The technical details about the magnitude of the centroid radius R obtained by the binary method belong to the prior art and are not described here in detail.

In this embodiment, the theoretical lamp point is a virtual lamp point. Those skilled in the art will appreciate that the special-shaped LED panel is formed by splicing modules, and the light points are integrated on the modules. The distribution of the light points on the modules is uniform, but due to the reasons of errors and the like of the splicing process, the physical splice joint and the splicing height difference exist between the modules, so that the distribution of the light points between the modules is possibly nonuniform, and the light points on a row or a column are possibly not on the same straight line. The theoretical lamp points ignore the problem of lamp point arrangement uniformity caused by the splicing, and all the following steps need to carry out coordinate correction on the theoretical lamp points.

In this embodiment, the application light points include an actual light point and a virtual light point, where the actual light point is a real light point in the special-shaped LED flat panel, and the actual light point is a light point within the outline range of the special-shaped LED flat panel after being corrected by coordinates through a theoretical light point; the virtual lamp point is a lamp point which is outside the outline range of the special-shaped LED plane screen and is positioned in the minimum circumscribed rectangle after the theoretical lamp point is corrected by coordinates, the gray values of all pixels in the rectangle range taking the virtual lamp point as the center and 2R as the side length are summed, and the virtual light spot brightness value of the virtual lamp point or the virtual lamp point brightness value is obtained, and the virtual lamp point brightness value is approximately 0. When the application lamp is adopted to perform subsequent display screen correction or display uniformity evaluation, the existence of the virtual lamp does not influence the accuracy of the result because the brightness value of the virtual lamp is approximately 0.

The technical effect of this embodiment is:

in the embodiment, the lamp point positioning is performed by mapping the special-shaped LED planar screen into a rectangular mode, the whole-screen lamp point positioning can be performed on the special-shaped LED planar screen with various shapes in a general mode, and the universality is good.

In this embodiment, the lamp point positioning information obtained by the special-shaped LED flat panel lamp point positioning method may be used for whole-screen correction or whole-screen display uniformity evaluation of the special-shaped LED flat panel, and the method adopted by the method is simpler and more practical and saves time and labor compared with the method adopting the traditional LED display screen correction or evaluation.

In a further embodiment, the step S6 in the positioning method of the special-shaped flat panel lamp spot according to the first embodiment is specifically as follows:

In the second embodiment, this embodiment will be described with reference to fig. 1 to 6, the embodiment is further defined in step S4 in the positioning method of the special-shaped flat screen lamp point according to the first embodiment, and the specific implementation content is as follows:

the step S4 specifically includes the following steps:

(xi,yj)=(xa+(xb-xa)/(Hn-1)×(j-1),ya+(yc-ya)/(Vn-1)×(i-1))。

。

in the third embodiment, referring to fig. 1 to fig. 6, the present embodiment is further defined by a centroid radius R in step S5 in the positioning method of the shaped flat screen lamp point according to the first embodiment, and the specific implementation contents are as follows:

the value range of the centroid radius R in the step S5 is [4,10 ], and the unit is a pixel.

In a fourth embodiment, referring to fig. 1 to fig. 6, the present embodiment is further defined in step S1 in the method for positioning a light spot of a shaped flat screen according to the first embodiment, and the specific implementation content is as follows:

the pure-color image of the special-shaped plane screen acquired in the step S1 is acquired by adopting an interlaced acquisition mode.

Description of the present embodiment:

in this embodiment, there are many prior art methods for acquiring the interlaced columns, and the general idea is to acquire images after lighting the lamps of n rows and n columns, and the specific intervals are determined according to the specific situation. The related technology can be referred to, and the vinca-dak electronic technology company grants an invention patent ZL201010613815.9, in the method for collecting the pixel lighting chromaticity information of the LED display screen, the collecting method.

In a fifth embodiment, referring to fig. 1 to fig. 6, a method for obtaining brightness information of a special-shaped flat screen according to the present embodiment is described as follows:

the method comprises the following steps:

ST1, adopting the special-shaped plane screen lamp point positioning method in the first embodiment to correct the lamp point of the pre-acquired solid-color image of the special-shaped plane screen, and obtaining the centroid coordinates and centroid radius R of the special-shaped plane screen for the application lamp point;

Description of the present embodiment:

in this embodiment, the spot brightness value is also referred to as a lamp spot brightness value; the theoretical light spot brightness value, which is also called as a theoretical light spot brightness value, refers to that a certain pixel is assumed to be a light spot, and the light spot brightness value is calculated; the theoretical spot brightness value of the lamp point is equal to the spot brightness value of the lamp point.

In this embodiment, chromaticity information of the lamp points may also be obtained according to the positioning method of the special-shaped flat screen lamp points in the first embodiment. Reference is made to the prior art for specific methods.

In this embodiment, the obtained brightness information of the special-shaped flat panel may be used in a correction method of a display screen. After the brightness values and/or chromaticity information of all the lamps are obtained, the correction coefficient can be calculated according to the brightness values and/or chromaticity information, and the display screen is corrected by the correction coefficient. Calculating brightness and/or chromaticity correction coefficients belongs to a general technical means in industry, and is not described herein.

In this embodiment, the obtained brightness information of the special-shaped flat panel may be used in a display uniformity evaluation method of a display screen. In the display uniformity evaluation method, standard deviation or a histogram is mostly utilized to quantitatively describe the display uniformity of the LED display screen after brightness correction.

In a sixth embodiment, referring to fig. 1 to fig. 6, the present embodiment provides a method for obtaining a correction coefficient of a deformed flat panel, which is specifically implemented as follows:

the method is specifically as follows;

Adopting the special-shaped plane screen lamp point positioning method according to the first embodiment, positioning the lamp points of the special-shaped plane screen according to the acquired picture Ti, and obtaining a centroid coordinate matrix Zi of the application lamp points corresponding to the acquired picture Ti;

Description of the present embodiment:

in this embodiment, the correction coefficient may be a luminance correction coefficient or a chrominance correction coefficient, and the correction coefficient may be used to correct a deformed flat screen.

In this embodiment, calculating the correction coefficient according to the spot brightness value (or brightness matrix) of the lamp spot belongs to a general technical means in industry, and will not be described here again.

In this embodiment, the application light points include an actual light point and a virtual light point. When the light spot brightness value of the virtual lamp point is approximately 0, the correction coefficient of the virtual lamp point can be set to be 1 when the brightness information of the application lamp point is adopted for correction, and the correction coefficient of the virtual lamp point is not actually present, so that the final correction result is not influenced.

In a further embodiment, taking luminance correction for a trapezoid display as an example, the following is explained:

the upper bottom edge and the lower bottom edge of the trapezoid display screen are parallel, and the brightness correction process is as follows:

(1) And controlling the display screen to respectively display three primary color images of red (255, 0) green (0,255,0) blue (0,0,255), and shooting by using a camera to obtain 3 acquired pictures P1, P2 and P3.

(2) And in the P1 image, obtaining the minimum circumscribed rectangle Dv of the figure outline of the trapezoid display screen.

(3) Calculating coordinates of four vertexes LT, LB, RT, RB of the minimum bounding rectangle Dv:

upper left corner LT coordinates (xa, ya) = (300 ), upper right corner RT coordinates (xb, ya) = (4300,300), lower left corner LB coordinates (xa, yc) = (300,1804), lower right corner RB coordinates (xb, yc) = (4300,1804).

(4) The number hn=250 of the horizontal longest row light points and the number vn=94 of the vertical longest column light points are given.

(5) And calculating a minimum circumscribed rectangle Dv according to the vertex coordinates and the number of the lamp points, and normally arranging centroid coordinate matrixes S of all theoretical lamp points:

；

the ith row and jth column point coordinates (xi, yj) in the S matrix represent the ith row and jth column theoretical lamp points S (i, j) in Dv, whose centroid coordinates are:

(xi,yj)=(xa+(xb-xa)/(Hn-1)×(j-1),ya+(yc-ya)/(Vn-1)×(i-1))

=（300+（4300-300）/249×（j-1）,300+(1804-300)/93×(i-1)），

wherein i is more than or equal to 1 and less than or equal to 94,1, j is more than or equal to 250.

(6) Coordinate correction is carried out on the theoretical lamp points to obtain the centroid coordinates of the application lamp points

Because of the physical joint and the joint height difference between the modules, the light points on one row or one column in the rectangle Dv may not be on the same straight line, and the theoretical centroid coordinate matrix S needs to be subjected to coordinate correction.

Before coordinate correction, the center radius R is calculated to be 4 pixels, and then coordinate correction is performed.

The coordinate correction method is as follows: performing traversing scanning on all adjacent pixels in a rectangular range with the side length of 2d by taking the centroid coordinates (i, j) of any theoretical lamp point in the S matrix as a center point, wherein d is 8 pixels; and calculating the theoretical facula brightness value of each adjacent pixel, namely the gray value sum in a rectangular area of 8×8 pixels with each adjacent pixel as a center. And traversing the calculation to obtain the adjacent pixel with the maximum theoretical light spot brightness value.

Setting the theoretical spot brightness value of a theoretical lamp point with the centroid coordinate of (i, j) as sum; the theoretical spot brightness value of the adjacent pixels with coordinates (i ', j ') is the largest among all the adjacent pixels, and the value is sum '; comparing sum with sum':

if sum > =sum', the centroid coordinate of the theoretical lamp point is the centroid coordinate of the application lamp point, namely (i, j), and the theoretical spot brightness value of the theoretical lamp point is the spot brightness value of the application lamp point;

If it is

The coordinates of the adjacent pixels are the centroid coordinates of the application light point, i.e. (i ', j') at this time, the theoretical spot brightness value of the adjacent pixel is the spot brightness value of the application lamp point.

And sequentially carrying out coordinate correction on other theoretical lamp points to obtain the centroid coordinates of the application lamp points.

(7) According to the previous step, the spot brightness value of the application lamp point is obtained, and then a corresponding brightness matrix L is obtained, which is expressed as:

；

wherein, L (i, j) is the spot brightness value of the ith row and the jth column of the red light emitting lamp points in the minimum circumscribed rectangle Dv. The brightness matrix L includes spot brightness values of the actual light spot and the virtual light spot, and the spot brightness value of the virtual light spot is approximately 0.

(8) Repeating the steps (2) - (7), and carrying out the same processing on the collected pictures P2 and P3 until the light spot brightness values of three primary colors (red, green and blue) are obtained on the display screen.

(9) Calculating a correction coefficient:

according to the light spot brightness value (or called the light spot brightness value), the brightness correction coefficient is calculated, which belongs to the technical means commonly used in industry and is not described herein. It should be noted that, when the spot brightness value of the virtual light point is approximately 0, the correction coefficient may be set to 1, and because the virtual light point does not actually exist, the correction coefficient of the virtual light point has no influence on the correction result, and the correction coefficient of the virtual light point may be normally uploaded to the control system.

In a further embodiment, taking brightness correction for an acute triangle display screen as an example, the following description is given:

(1) And controlling the display screen to display three primary color images red (255, 0) green (0,255,0) blue (0,0,255) respectively, and shooting by using a camera to acquire pictures. The method adopts an interlaced acquisition mode, specifically adopts a mode of lighting up the lamp spots at intervals of 2 rows and 2 columns to acquire images, and is called a 2X 2 acquisition mode for short. With a 2 x 2 acquisition mode, 4 pictures are acquired per single base color. The three single primary colors require 12 pictures to be acquired and are recorded as a picture sequence P1-P12. Red light point information is included in the picture sequences P1 to P4, green light point information is included in the picture sequences P5 to P8, and blue light point information is included in the picture sequences P9 to P12.

(2) In the P1 image, the longest edge of the acute triangle is taken as the base, and the minimum circumscribed rectangle Dv of the figure outline of the acute triangle display screen is obtained.

upper left corner LT coordinates (xa, ya) = (200 ), upper right corner RT coordinates (xb, ya) = (3500,200), lower left corner LB coordinates (xa, yc) = (200,2000), lower right corner RB coordinates (xb, yc) = (3500,2000).

(4) Given an initial number of laterally longest rows shn=600 and an initial number of longitudinally longest columns svn=164, due to the acquisition mode of 2 rows and 2 columns, the final number of laterally longest rows hn=600/2=300 and the number of longitudinally longest columns vn=164/2=82.

；

(xi,yj)=(xa+(xb-xa)/(Hn-1)×(j-1),ya+(yc-ya)/(Vn-1)×(i-1))

=（200+（3500-200）/299×（j-1）,200+(2000-200)/81×(i-1)），

wherein i is more than or equal to 1 and less than or equal to 82,1, j is more than or equal to 300.

Before coordinate correction, the center radius R is calculated to be 5 pixels, and then coordinate correction is performed.

The coordinate correction method is as follows: performing traversing scanning on all adjacent pixels in a rectangular range with the side length of 2d by taking the centroid coordinates (i, j) of any theoretical lamp point in the S matrix as a center point, wherein d is 10 pixels; and calculating the theoretical facula brightness value of each adjacent pixel, namely the gray value sum in a 10×10 pixel rectangular area with each adjacent pixel as a center. And traversing the calculation to obtain the adjacent pixel with the maximum theoretical light spot brightness value.

if it is

The coordinates of the adjacent pixels are centroid coordinates of the application lamp points, namely (i ', j') theoretical spot brightness values of the adjacent pixels at the moment are spot brightness values of the application lamp points. />

；

(8) Repeating the steps (2) - (7), and carrying out the same processing on the collected pictures P2-P12 until the light spot brightness values of three primary colors (red, green and blue) are obtained on the display screen.

(9) Calculating a correction coefficient:

In a further embodiment, taking a circular display screen as an example, chromaticity correction is performed as follows:

(1) And controlling the display screen to display three primary color images red (255, 0) green (0,255,0) blue (0,0,255) respectively, and shooting by using a camera to acquire pictures. Because of the need of obtaining the brightness and chromaticity information of the pixel points for chromaticity correction, 3 collected pictures need to be taken by a single primary color, 9 pictures need to be taken by three primary colors to obtain a picture sequence P1-P9, and an interlaced collection mode is not adopted here.

(2) In the P1 image, the minimum circumscribed rectangle Dv of the graph outline of the circular display screen is obtained by taking the circular diameter d as the side length of the square.

upper left corner LT coordinates (xa, ya) = (300 ), upper right corner RT coordinates (xb, ya) = (4300,300), lower left corner LB coordinates (xa, yc) = (300,4300), lower right corner RB coordinates (xb, yc) = (4300).

(4) The number hn=222 of the horizontal longest row light points and the number vn=222 of the vertical longest column light points are given.

；

(xi,yj)=(xa+(xb-xa)/(Hn-1)×(j-1),ya+(yc-ya)/(Vn-1)×(i-1))

=（300+（4300-300）/221×（j-1）,300+(4300-300)/221×(i-1)），

wherein i is more than or equal to 1 and less than or equal to 222,1, j is more than or equal to 222.

if it is

The coordinates of the adjacent pixels are centroid coordinates of the application lamp points, namely (i ', j') theoretical spot brightness values of the adjacent pixels at the moment are spot brightness values of the application lamp points.

；

The chromaticity information of the application lamp point can also be obtained according to the centroid coordinates of the application lamp point and the acquired image, and the chromaticity information obtaining method is a conventional technology and is not described in detail herein.

And obtaining the brightness value of the application lamp according to the light spot brightness value and the chromaticity information of the application lamp.

(8) Repeating the steps (2) - (7), and performing the same processing on the collected pictures P2-P12 until the red, green and blue brightness and chromaticity information (i.e. light instability) of all the lamps are obtained on the display screen.

(9) Calculating a correction coefficient:

the chromaticity correction coefficient is calculated according to the lighting chromaticity value of the applied lamp, which belongs to the technical means commonly used in industry and is not described herein. It should be noted that, when the brightness value of the virtual light point is approximately 0, the correction coefficient may be set to 1, and because the virtual light point does not actually exist, the correction coefficient of the virtual light point has no influence on the correction result, and the correction coefficient of the virtual light point may be normally uploaded to the control system.

In a seventh embodiment, referring to fig. 1 to fig. 6, a method for evaluating display uniformity of a special-shaped flat screen is provided in this embodiment, and the specific implementation content is as follows:

the method is specifically as follows;

according to the special-shaped plane screen lamp point positioning method, lamp points are positioned according to the acquired picture Ti, and a centroid coordinate matrix Zi of the application lamp points corresponding to the acquired picture Ti is obtained;

Description of the present embodiment:

in this embodiment, to evaluate display uniformity of a special-shaped flat panel, brightness correction is performed on the special-shaped flat panel; and then, extracting the lamp lighting information of the special-shaped plane screen subjected to brightness correction, and calculating standard deviation according to the lamp lighting information, so as to evaluate the display uniformity of the display screen. For details, see the university of western electronic technology, the university of s, national institute of technology, dong Wenxiao, university of s, treatises on the law: the third chapter, the fifth section, of research on the brightness and chromaticity uniformity algorithm of an LED display screen based on CCD camera measurement.

In a further embodiment, the brightness uniformity evaluation refers to evaluating the display effect of the display screen after brightness correction to check the result of the display screen correction. The correction method specifically adopted by the display screen subjected to brightness correction is not limited, and is not limited to the correction method herein. In the following, an evaluation of brightness uniformity of a rounded rectangular display is taken as an example, and specifically the following is described:

the round corner rectangular display screen is parallel in upper and lower bottom edges and equal in length, subjected to brightness correction, and subjected to brightness uniformity evaluation as follows:

(1) And controlling the rounded rectangular display screen to respectively display three primary color images of red (255, 0) green (0,255,0) blue (0,0,255), and shooting by using a camera to obtain 3 acquired pictures P1, P2 and P3.

(2) In the P1 image, the upper bottom edge and the lower bottom edge of the rounded rectangular display screen are taken as rectangular long edges, and the minimum circumscribed rectangle Dv of the graphic outline of the rounded rectangular display screen is obtained.

upper left corner LT coordinates (100 ), upper right corner RT coordinates (4600,100), lower left corner LB coordinates (100,2260), lower right corner RB coordinates (4600,2260).

(4) The shaped screen is given the number hn=250 of the horizontal longest row light points and the number vn=125 of the vertical longest column light points.

；

(xi,yj)=(xa+(xb-xa)/(Hn-1)×(j-1),ya+(yc-ya)/(Vn-1)×(i-1))

=（100+（4600-100）/249×（j-1）,100+(2260-100)/124×(i-1)），

wherein i is more than or equal to 1 and less than or equal to 125,1, j is more than or equal to 250.

if it is

；

(8) Repeating the steps (2) - (7), and carrying out the same processing on the collected pictures P2 and P3 until the brightness-corrected round-corner rectangular display screen is obtained, wherein all the light points are displayed as light spot brightness values after three primary colors (red, green and blue).

(9) Calculating display screen uniformity

And calculating standard deviation according to the calculated brightness value of the lamp point of the rounded rectangular display screen after brightness correction, thereby evaluating the brightness uniformity of the display screen. For detailed methods, see, the university of electronic technology, west An, university of electronic technology, the Shuoshi thesis of Dong Wenxiao, the third chapter, the fifth section, in the research on the brightness and chromaticity uniformity algorithm of LED display screens based on CCD camera measurement.

An eighth embodiment, referring to fig. 1 to fig. 6, describes the present embodiment, and provides a positioning device for a light point of a special-shaped flat screen, which is specifically implemented as follows:

the device specifically comprises:

module 1: the method is used for setting up a rectangular coordinate system taking pixels as a unit on a pre-acquired pure-color image of the special-shaped plane screen;

module 2: the minimum circumscribed rectangle Dv is used for drawing the outline of the special-shaped plane screen in the rectangular coordinate system;

module 3: the coordinates of four vertexes used for obtaining the minimum circumscribed rectangle Dv in a calculation manner in the rectangular coordinate system, namely, the coordinates of the top left corner vertex LT are (xa, ya), the coordinates of the top right corner vertex RT are (xb, ya), the coordinates of the bottom left corner vertex LB are (xa, yc), and the coordinates of the bottom right corner vertex RB are (xb, yc);

module 4: the method comprises the steps of constructing a rectangular array in a minimum circumscribed rectangle Dv according to four vertex coordinates, a preset number Hn of horizontal longest row light points and a preset number Vn of longitudinal longest column light points, wherein the rectangular array consists of Vn rows and Hn columns of uniformly arranged pixel points, the pixel points used for forming the rectangular array are theoretical light points, the theoretical light points at four vertexes of the rectangular array coincide with the four vertexes of the minimum circumscribed rectangle Dv, and calculating to obtain the centroid coordinates of each theoretical light point in the rectangular array and centroid coordinate matrixes S of all theoretical light points;

Module 5: the module is used for calculating and obtaining the light spot radius R according to the pre-acquired solid-color image of the special-shaped plane screen;

and (6) module 6: and the system is used for carrying out coordinate correction on the theoretical lamp points in the rectangular array, and calculating to obtain centroid coordinates and centroid coordinate matrixes of the application lamp points corresponding to the theoretical lamp points.

The special-shaped plane screen lamp point positioning device is used for executing the special-shaped plane screen lamp point positioning method in the first embodiment.

In a still further embodiment, according to the eighth embodiment, the positioning device for a shaped flat screen lamp spot, the module 6 specifically includes:

sub-module 6.1: the method comprises the steps of selecting a theoretical lamp point from the rectangular array, and calculating to obtain a theoretical light spot brightness value of the theoretical lamp point;

sub-module 6.2: traversing all adjacent pixels of the theoretical lamp points, and acquiring a theoretical spot brightness value of each adjacent pixel; the adjacent pixels are pixels which are contained in a rectangular range with the theoretical lamp point as the center and the side length of 2d, wherein R is more than or equal to d and less than or equal to 2R, and the unit is the pixel; the theoretical light spot brightness value is the gray value sum of all pixel points in a rectangular range with the side length of 2R by taking the theoretical light point or adjacent pixels as the center;

Sub-module 6.3: and comparing the theoretical facula brightness value of the theoretical lamp point with the theoretical facula brightness value of the adjacent pixels, and selecting according to the following conditions:

sub-module 6.4: and the method is used for repeatedly calling the sub-modules 6.1-6.3 until all theoretical lamp points are subjected to coordinate correction, the centroid coordinates of the corresponding application lamp points are obtained, and the positioning of the special-shaped plane screen lamp points is completed.

The technical solution provided by the present invention is described in further detail through several specific embodiments, so as to highlight the advantages and benefits of the technical solution provided by the present invention, however, the above specific embodiments are not intended to be limiting, and any reasonable modification and improvement, reasonable combination of embodiments, equivalent substitution, etc. of the present invention based on the spirit and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. The positioning method for the special-shaped plane screen lamp points is characterized by comprising the following steps of:

s6, carrying out coordinate correction on the theoretical lamp points in the rectangular array, and calculating to obtain centroid coordinates and centroid coordinate matrixes of the application lamp points corresponding to the theoretical lamp points, so as to finish lamp point positioning;

the step S6 specifically includes the following steps:

2. The method for positioning the lamp spot of the shaped flat screen according to claim 1, wherein the step S4 is specifically as follows:

(xi,yj)=(xa+(xb-xa)/(Hn-1)×(j-1),ya+(yc-ya)/(Vn-1)×(i-1))；

。

3. the method for positioning a light spot on a shaped flat screen according to claim 1, wherein the light spot radius R in the step S5 has a value range of [4,10 ] in pixels.

4. The method for positioning the lamp spot of the shaped flat screen according to claim 1, wherein the pre-acquired solid-color image of the shaped flat screen in step S1 is acquired by adopting an interlaced acquisition mode.

5. The method for obtaining the brightness information of the special-shaped flat screen is characterized by comprising the following steps of:

ST1, performing lamp point correction on a pre-acquired solid-color image of the special-shaped plane screen by adopting the special-shaped plane screen lamp point positioning method of claim 1 to obtain centroid coordinates of an application lamp point of the special-shaped plane screen;

6. The method for acquiring the correction coefficient of the special-shaped plane screen is characterized by comprising the following steps of;

Adopting the special-shaped plane screen lamp point positioning method according to claim 1, positioning the lamp points of the special-shaped plane screen according to the acquired picture Ti, and obtaining a centroid coordinate matrix Zi of the application lamp points corresponding to the acquired picture Ti;

7. The method for evaluating the display uniformity of the special-shaped flat screen is characterized by comprising the following steps of;

adopting the special-shaped plane screen lamp point positioning method according to claim 1 to position the lamp points of the special-shaped plane screen according to the acquired picture Ti, and obtaining a centroid coordinate matrix Zi of the application lamp points corresponding to the acquired picture Ti;

8. A computer device, comprising: a processor and a memory, wherein the memory is configured to store executable instructions of the processor, and the processor is configured to execute the method for positioning the deformed flat screen lamp spot according to any one of claims 1 to 4, or execute the method for obtaining the deformed flat screen brightness information according to claim 5, or the method for obtaining the deformed flat screen correction coefficient according to claim 6, or the method for evaluating the deformed flat screen display uniformity according to claim 7, by executing the executable instructions.

9. A computer storage medium, wherein a computer program is stored in the storage medium, and when the computer program runs, the method for positioning the lamp point of the special-shaped flat screen according to any one of claims 1 to 4 is executed, the method for obtaining brightness information of the special-shaped flat screen according to claim 5 is executed, the method for obtaining correction coefficient of the special-shaped flat screen according to claim 6 is executed, or the method for evaluating display uniformity of the special-shaped flat screen according to claim 7 is executed.