A LED display screen calibration method for adjusting configuration files during acquisition

Abstract

The present invention relates to a method for correcting an LED display screen by adjusting a configuration file during acquisition. When the LED display screen is acquired every n rows and every m columns and has poor uniformity, the method adjusts the refresh frequency in the configuration file of the LED display screen control system or adjusts the refresh frequency and gamma at the same time, and uses the acquisition method of every n rows and every m columns under the adjusted configuration file to correct any acquisition area on the LED display screen; until the "mosaic" phenomenon of the corrected acquisition area is eliminated; and uses the acquisition method of every n rows and every m columns under the configuration file at this time to correct all areas of the LED display screen; after the correction is completed, the factory configuration file M0 is reloaded. The present invention can make the surface display and the alternate row and column display brightness consistent, and eliminate the "mosaic" phenomenon after the alternate row and column acquisition correction.

Description

Technical Field

[0001] The invention relates to a correction method for an LED display screen, and in particular to a correction method for an LED display screen for adjusting a configuration file during acquisition. Background Art

[0002] Due to the discreteness of LED light-emitting chips and the influence of the display manufacturing process, LED displays will have problems with brightness or chromaticity unevenness, which manifests as "pockmarked" or "mosaic" color blocks on the entire screen. In order to solve the above problems, correction technology has been developed, which can greatly improve the brightness and chromaticity consistency of the display. The correction technology collects the brightness and chromaticity information of each LED pixel through an area array camera, calculates the point-by-point correction coefficient matrix through data extraction, and loads the correction coefficient matrix into the control system to compensate for the inconsistency in brightness and chromaticity. The acquisition process can achieve surface acquisition (such as ) when the camera resolution is large enough and the pixel resolution of the display is reasonable. Figure 1 ), but as LED displays develop towards ultra-high density and ultra-small pitch indoors, the number of LED pixels that can be collected in one acquisition is limited, and it is necessary to move the camera position multiple times for splicing acquisition. However, multiple splicing and moving the camera is not only time-consuming and labor-intensive, but also affects the correction effect. Therefore, an alternate row and column acquisition method is generated (such as Figure 2 ). Although this method prolongs the single correction time, it can greatly improve the pixel resolution of a single acquisition and effectively reduce the number of splicing acquisitions. However, when the interlaced row and column acquisition method is used for correction, some display screens will still have obvious "mosaic" phenomenon after correction. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a method for correcting an LED display screen by adjusting a configuration file during acquisition, which method can solve the "mosaic" phenomenon that occurs after correction during alternate row and column acquisition correction.

[0004] In order to solve the above technical problems, the LED display screen correction method of adjusting the configuration file during acquisition of the present invention can adopt the following two technical solutions:

[0005] Technical solution 1:

[0006] Select a collection area on the LED display screen, light up all the LED lights in the collection area, and use the camera to obtain the surface collection image of the collection area; perform centroid positioning and segmentation on each LED light point in the surface collection image and extract the grayscale value of each LED light point to form the grayscale matrix C1 of the surface collection image of the collection area;

[0007] The LED light points in the acquisition area are displayed in an alternate n-row and m-column manner. The rows and columns of the LED light points lit in the acquisition area each time are different from those of the LED light points lit in other times. Each time the camera is used to acquire the image of the acquisition area in alternate rows and columns. The image is displayed n×m times in total to obtain n×m alternate row and column images. The centroid of each LED light point in the alternate row and column image is segmented and the gray value of each LED light point is extracted to obtain the gray matrix of n×m alternate row and column images. The gray matrix of the n×m alternate row and column images is merged into the gray matrix C2 of the acquisition area according to the corresponding positions.

[0008] If the error between C1 and C2 is within ±3%, the LED display screen is calibrated by using the alternate row and alternate column acquisition method; otherwise, the refresh frequency and gamma value in the configuration file of the LED display screen control system are adjusted, and alternate row and alternate column images are repeatedly acquired and the acquisition area grayscale matrix C2 is synthesized until the error between C1 and C2 is within ±3%, and the configuration file M1 is saved at this time;

[0009] The configuration file M1 is loaded to all cabinets of the LED display screen, and the LED display screen is calibrated by using an alternate row and alternate column acquisition method to obtain a calibrated LED display screen.

[0010] After all areas of the LED display have been calibrated, load the factory configuration file M0.

[0011] The collection area is a box or a module.

[0012] Said n=2-16, m=2-16.

[0013] Technical solution 2:

[0014] When the "mosaic" phenomenon occurs when the LED display screen is collected every n rows and m columns, adjust the refresh frequency in the configuration file of the LED display control system and use the "every n rows and m columns" collection method under the configuration file to correct any collection area on the LED display screen;

[0015] After the calibration is completed, if the "mosaic" phenomenon still occurs in the acquisition area, repeatedly adjust the refresh frequency and recalibrate the acquisition area using the acquisition method of every n rows and every m columns until the "mosaic" phenomenon in the corrected acquisition area is eliminated, and save the configuration file at this time as M1; load the configuration file M1 to all acquisition areas of the LED display screen, and calibrate the LED display screen using the acquisition method of every n rows and every m columns.

[0016] After all areas of the LED display are calibrated, reload the factory configuration file M0.

[0017] The above M0 is the factory configuration file of the display, which can ensure that the display is optimal in terms of refresh, coupling, brightness, low gray, etc., but it does not take into account the problem of interlaced row and column display, which may affect the correction effect.

[0018] Beneficial effects:

[0019] The present invention adopts a method of adjusting the refresh frequency in the control system configuration file, and uses an alternate row and column acquisition method to perform full-screen correction under the new configuration file, which can make the brightness of the surface display and the alternate row and column display consistent and eliminate the "mosaic" phenomenon. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Flowchart of the present invention.

[0021] Figure 2 It is a schematic diagram of the LED display screen display.

[0022] Figure 3 is 3a~ Figure 3d Collect the 1st to 4th display schematic diagrams for every 2 rows and 2 columns of the LED display screen.

[0023] Figure 4 This is a schematic diagram of the LED display screen with 8 rows and 8 columns. DETAILED DESCRIPTION

[0024] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0025] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood in specific circumstances.

[0026] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" or "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0027] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0028] Example 1

[0029] A 60-megapixel resolution camera is used to calibrate the P0.9 display screen, and the resolution of a single cabinet is 640×360 (width×height).

[0030] like Figure 1 As shown, the LED display screen correction method of adjusting the configuration file during acquisition of the present invention is as follows:

[0031] 1. If Figure 2 As shown, a box is selected as the acquisition area on the LED display screen, and all its LED lights are lit. The camera is used to acquire the box surface acquisition image; the centroid of each LED light point in the surface acquisition image is segmented and the gray value of each LED light point is extracted to form the gray matrix C1 of the box surface acquisition image. The method of locating and segmenting the centroid of the LED light point and calculating the point-by-point correction coefficient matrix is ​​a common technical means in the industry.

[0032] Second, the LED lights of the cabinet are displayed in every 2 rows and columns. The rows and columns of the LED lights on the cabinet are different from those on other displays. Each time, the camera is used to collect the images of the cabinet in every other row and column. Figure 3a , 3bAs shown in 3c and 3d, a total of 4 interlaced images are obtained; the centroid of each LED light point in the interlaced images is segmented and the gray value of each LED light point is extracted to obtain the gray matrix of the 4 interlaced images. The gray matrices of the 4 interlaced images are merged into a box gray matrix C2 according to the corresponding positions. C2 and C1 have the same resolution (640×360).

[0033] 3. Compare C1 and C2. If they are equal, it proves that the linear relationship of the brightness of this batch of tube cores is not affected by the acquisition method. The existing alternate row and alternate column acquisition method is used to calibrate the LED display. If they are not equal, it proves that there is a problem of inconsistent brightness between the surface display and the alternate point display of this batch of tube cores, and the configuration file needs to be changed.

[0034] 4. Adjust the refresh rate and gamma value in the configuration file of the LED display control system (control the maximum brightness of the display by adjusting the gamma value); repeat steps 2 and 3 until C1=C2, and save the configuration file M1. At this time, it is proved that under the configuration file M1, the luminous brightness of each LED light point collected when the display cabinet is displayed on the surface and when it is displayed in alternate rows and columns is consistent;

[0035] 5. Load the configuration file M1 to all cabinets of the LED display screen, and calibrate the LED display screen using the existing alternate row and alternate column acquisition method; after the calibration is completed, send the initial configuration file M0 to all cabinets of the LED display screen.

[0036] In the steps 1 and 2, the LED light point can display any color of red, green or blue, and ensure that the same grayscale is used in the steps 1 and 2.

[0037] The entire acquisition process must ensure that the parameters that affect the acquisition brightness, such as the camera aperture, focal length, exposure time, etc. remain unchanged. At the same time, the maximum brightness of the LED display must be kept constant. The calibration operation is performed after the LED display is thermally balanced.

[0038] Taking into account the system noise (the influence of the area array camera's own noise, the surrounding environment, the LED display brightness attenuation, etc.), C1 and C2 are not absolutely equal in a strict sense. The two are considered equal within an error of ±3%.

[0039] The steps 1 and 2 described above can be interchanged.

[0040] Example 2

[0041] A 20-megapixel resolution camera is used to calibrate the P0.9 display screen, and the resolution of a single cabinet is 640×360 (width×height).

[0042] The LED display screen correction method of the present invention for adjusting the configuration file during acquisition is as follows:

[0043] 1. Select a module with a resolution of 160×120 on the LED display screen as the acquisition area, light up all its LED lights, and use the camera to acquire the module surface acquisition image; perform centroid positioning and segmentation on each LED light point in the surface acquisition image and extract the grayscale value of each LED light point to form the grayscale matrix C1 of the module surface acquisition image.

[0044] 2. The LED light points of the module are displayed in 8 rows and 8 columns. The rows and columns of the LED light points lit on the module each time are different from those lit in other displays. Each time the camera is used to collect the corresponding images of the module in alternate rows and columns, such as Figure 4 As shown, a total of 64 interlaced images are obtained; the centroid of each LED light point in the interlaced images is segmented and the grayscale value of each LED light point is extracted to obtain the grayscale matrix of 64 module interlaced images. The grayscale matrices of the 64 interlaced images are combined into the cabinet display grayscale matrix C2 according to the corresponding positions. C2 and C1 have the same resolution (640×360).

[0045] 3. Compare C1 and C2. If they are equal, it proves that the linear relationship of the brightness of this batch of tube cores is not affected by the acquisition method. The existing alternate row and alternate column acquisition method is used to calibrate the LED display. If they are not equal, it proves that there is a problem of inconsistent brightness between the surface display and the alternate point display of this batch of tube cores, and the configuration file needs to be changed.

[0046] 4. Adjust the refresh rate and gamma value in the configuration file of the LED display control system (control the maximum brightness of the display by adjusting the gamma value); repeat steps 2 and 3 until C1=C2, and save the configuration file M1. This proves that under the configuration file M1, the luminous brightness of each LED light point collected when the display module is displayed on the surface and when it is displayed in alternate rows and columns is consistent;

[0047] 5. Load the configuration file M1 to all cabinets of the LED display screen, and calibrate the LED display screen using the existing alternate row and alternate column acquisition method; after the calibration is completed, send the initial configuration file M0 to all cabinets of the LED display screen.

[0048] In the steps 1 and 2, the LED light point can display any color of red, green or blue, and ensure that the same grayscale is used in the steps 1 and 2.

[0049] The entire acquisition process must ensure that the parameters that affect the acquisition brightness, such as the camera aperture, focal length, exposure time, etc. remain unchanged. At the same time, the maximum brightness of the LED display must be kept constant. The calibration operation is performed after the LED display is thermally balanced.

[0050] Taking into account the system noise (the influence of the area array camera's own noise, the surrounding environment, the LED display brightness attenuation, etc.), C1 and C2 are not absolutely equal in a strict sense. The two are considered equal within an error of ±3%.

[0051] The steps 1 and 2 described above can be interchanged.

[0052] When the camera resolution allows, the cabinet or module surface is displayed and captured. If the camera resolution is small, only one or several modules can be captured. If the camera resolution is high, a single cabinet can be captured. The resolution of a single capture area depends on the resolution of the area array camera used for capture.

[0053] Example 3

[0054] A 10-megapixel resolution camera is used to calibrate the P1.27 display screen, and the resolution of a single cabinet is 480×270 (width×height).

[0055] When the "mosaic" phenomenon appears after the LED display screen is calibrated by using the acquisition method of every 3 rows and every 3 columns, adjust the refresh frequency in the configuration file of the LED display screen control system and calibrate any acquisition area of ​​the LED display screen by using the acquisition method of every 3 rows and every 3 columns under the configuration file;

[0056] After the calibration is completed, observe the calibration effect with the naked eye. If the acquisition area still has the "mosaic" phenomenon, repeatedly adjust the refresh frequency and use the acquisition method of every 3 rows and columns to recalibrate the acquisition area until the "mosaic" phenomenon in the acquisition area is eliminated after calibration, and save the configuration file at this time as M1; load the configuration file M1 to all acquisition areas of the LED display screen, and use the acquisition method of every 3 rows and columns to calibrate the LED display screen.

[0057] After all areas of the LED display are calibrated, reload the factory configuration file M0.

[0058] When the inventor used the interlaced row and column acquisition method to calibrate the LED display screen, the display screen occasionally showed obvious "mosaic" phenomenon after correction; during the experiment, it was accidentally discovered that some LED light-emitting chips were affected by the drive control and had inconsistent brightness between the interlaced row and column display and the surface display. Some chips even showed a darker state when displayed on the surface, but a brighter state when displayed on the interlaced row and column. This would cause the brightness and chromaticity data collected by the interlaced row and column to deviate from that when displayed on the surface; the inventor tried to adjust the control system current gain to make the interlaced row and column display consistent with the surface display acquisition brightness, but after multiple adjustments and corrections, the "mosaic" phenomenon was still not improved. He tried to replace the camera and use the color correction method, and found that the display screen still had obvious bright and dark blocks after correction. The brightness meter test found that the brightness was not corrected. He tried to use the surface acquisition correction method, and the consistency was improved, but the single correction pixels of the surface acquisition were limited, and the super large screen must use the interlaced row and column acquisition mode. Therefore, the surface acquisition can only be verified on a single box, and there is still no suitable method for a large screen. Finally, the method of the present invention is used to adjust the refresh frequency or adjust the refresh frequency and gamma value at the same time to eliminate the "mosaic" phenomenon.

Claims

1. A method for calibrating an LED display screen by adjusting a configuration file during acquisition, characterized in that The method is as follows: Select a collection area on the LED display screen, light up all the LED lights in the collection area, and use the camera to obtain the surface collection image of the collection area; perform centroid positioning and segmentation on each LED light point in the surface collection image and extract the grayscale value of each LED light point to form the grayscale matrix C1 of the surface collection image of the collection area; The LED light points in the acquisition area are displayed in an alternate n-row and m-column manner, and the rows and columns of the LED light points lit in the acquisition area each time are different from those of the LED light points lit in other times; each time the camera is used to acquire the acquisition area alternate row and column images, and a total of n×m images are displayed, obtaining n×m alternate row and column images; the centroid of each LED light point in the alternate row and column images is segmented and the gray value of each LED light point is extracted to obtain the gray matrix of n×m alternate row and column images; the gray matrix of the n×m alternate row and column images is merged into the acquisition area gray matrix C2 according to the corresponding positions; If the error between C1 and C2 is within ±3%, the LED display screen is calibrated by using the alternate row and alternate column acquisition method; otherwise, the refresh frequency and gamma value in the configuration file of the LED display screen control system are adjusted, and alternate row and alternate column images are repeatedly acquired and the acquisition area grayscale matrix C2 is synthesized until the error between C1 and C2 is within ±3%, and the configuration file M1 is saved at this time; The configuration file M1 is loaded to all cabinets of the LED display screen, and the LED display screen is calibrated by using the alternate row and alternate column acquisition method to obtain the calibrated LED display screen; finally, the factory configuration file M0 is reloaded.

2. The LED display screen correction method of adjusting the configuration file during acquisition according to claim 1, characterized in that The collection area is a box or a module.

3. The LED display screen correction method of adjusting the configuration file during acquisition according to claim 1, characterized in that Said n=2-16, m=2-16.

4. A method for calibrating an LED display screen by adjusting a configuration file during acquisition, characterized in that The method is as follows: When the "mosaic" phenomenon occurs when the LED display screen is collected every n rows and m columns, adjust the refresh frequency in the configuration file of the LED display control system and use the collection method of every n rows and m columns to correct any collection area on the LED display screen under the configuration file; After the calibration is completed, if the "mosaic" phenomenon still occurs in the acquisition area, repeatedly adjust the refresh frequency and recalibrate the acquisition area using the acquisition method of every n rows and every m columns until the "mosaic" phenomenon in the acquisition area after calibration is eliminated, and save the configuration file at this time as M1; load the configuration file M1 to all acquisition areas of the LED display screen, and calibrate the LED display screen using the acquisition method of every n rows and every m columns; finally, reload the factory configuration file M0.

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