A method, device and storage medium for screen brightness correction extraction

Abstract

The present application discloses a method, device and storage medium for screen brightness correction extraction, which is used to improve the accuracy of pixel brightness extraction. An image of a standard light source is collected by a sampling camera to generate a light source captured image; the screen is lit using the lit image, and an image is collected by the sampling camera to generate a screen captured image; the light source captured image and the screen captured image are subjected to region segmentation; a luminance meter is used to detect the luminance of the segmented regions on the light source captured image and the screen captured image; the grayscale mean data of the segmented regions on the light source captured image and the screen captured image is calculated; a correction coefficient is generated according to the luminance data and the grayscale mean data of the segmented regions; the screen captured image is corrected using the correction coefficient; pixel position correction is performed on the screen captured image after grayscale correction; pixel brightness information extraction is performed on the screen captured image after position correction is completed to generate a brightness extraction result image.

Description

Technical Field

[0001] Embodiments of the present application relate to the field of display screen detection, and in particular, to a method, device, and storage medium for screen brightness correction and extraction. Background Art

[0002] In the field of display screen detection, it is usually necessary to detect different types of defects on the display screen. The defect detection and defect compensation links are important production links. When different display screen structures generate the same type of defect, their manifestation forms are also different. In order to improve the quality of display screen products, De-Mura is still an essential link in the panel process. The compensation process of De-Mura is based on the gray-scale values of each Pattern image captured by a high-resolution camera. Before starting the algorithm processing, the program will go through a series of image preprocessings to make the gray-scale differences of each image more accurately restore the mura form of the panel itself. In order to improve the detection accuracy, it is necessary to accurately extract the brightness data of the display screen itself. In the existing process of extracting the display screen brightness, high-precision acquisition devices are usually used and a good acquisition environment is set.

[0003] However, there are still many problems in the process of brightness extraction. First, in the continuous update and iteration process of the display screen, various new types of screens such as curved screens and foldable screens have emerged. And in order to increase the functionality of the display screen, on the basis of adding a PCB structure under the original display screen, a thin-film circuit is also selected to be added under the pixel layer of the display screen. The thin-film circuit is used to control the structure on the pixel layer. Such a thin-film circuit has a certain reflection ability, which will affect the brightness of the display screen and thus affect the extraction of the display screen brightness. Such a circuit structure is usually set at the bottom edge part of the display screen because the display function in this part of the area allows a certain brightness error. Second, due to the characteristics of the optical FA lens of the acquisition camera, when the display screen product is relatively large, it is also easy to have a difference in the collected brightness between the center and the edge of the product, which makes it more difficult to extract the brightness of the edge part of the display screen and reduces the accuracy of pixel brightness extraction. Summary of the Invention

[0004] The present application discloses a method, device, and storage medium for screen brightness correction and extraction, which are used to improve the accuracy of pixel brightness extraction.

[0005] In a first aspect, an embodiment of the present application provides a method for screen brightness correction extraction, including: starting a standard light source, using a sampling camera to collect an image of the standard light source to generate a light source captured image; designing a lighting image according to the standard light source, using the lighting image to light the screen, and using the sampling camera to collect an image of the lit screen to generate a screen captured image; performing region segmentation on the light source captured image and the screen captured image according to a preset segmentation accuracy, and generating a number of corresponding segmentation regions on the light source captured image and the screen captured image; using a luminance meter to detect the brightness of the segmentation regions on the light source captured image and the screen captured image; calculating the grayscale mean data of the segmentation regions on the light source captured image and the screen captured image; generating a correction coefficient according to the brightness data and the grayscale mean data of the segmentation regions; using the correction coefficient to correct the image of the screen captured image; performing pixel position correction on the screen captured image after grayscale correction; and extracting pixel brightness information from the screen captured image after position correction is completed to generate a brightness extraction result map.

[0006] Optionally, the screen is a curved screen with a thin-film circuit added after the pixel layer. The curved screen includes a flat region and a curved region, and the thin-film circuit is located on the curved part of the screen body. The step of performing region segmentation on the light source captured image and the screen captured image according to a preset segmentation accuracy, and generating a number of corresponding segmentation regions on the light source captured image and the screen captured image includes: determining a first flat region and a first curved region in the screen captured image; drawing a second flat region and a second curved region according to the corresponding positions of the first flat region and the first curved region on the light source captured image; performing region segmentation on the first flat region and the second flat region according to a preset first segmentation accuracy to generate a number of corresponding flat segmentation regions; and performing region segmentation on the first curved region and the second curved region according to a preset second segmentation accuracy to generate a number of corresponding curved segmentation regions.

[0007] Optionally, after the step of using a luminance meter to detect the brightness of the segmentation regions on the light source captured image and the screen captured image, and before the step of calculating the grayscale mean data of the segmentation regions on the light source captured image and the screen captured image, the method further includes: obtaining the curvature data and pixel pitch data of the curved part of the screen, and generating vertical scattering degree data according to the curvature data and the pixel pitch data; obtaining the reflectivity data of the thin-film circuit; and performing curved surface brightness correction on the brightness data of the curved surface segmentation regions of the screen according to the vertical scattering degree data and the reflectivity data.

[0008] Optionally, after the step of calculating the grayscale mean data of the segmentation regions on the light source captured image and the screen captured image, and before generating a correction coefficient according to the brightness data and the grayscale mean data of the segmentation regions, the method further includes: correcting the curved surface grayscale according to the reflectivity data of the thin-film circuit.

[0009] Optionally, the steps of correcting the pixel positions of the screen captured image after gray correction include: designing a positioning screen, using the positioning screen to light up the screen, with positioning points set on the positioning image, and the positions of the positioning points being determined by the screen type; using a sampling camera to capture an image of the screen to generate a screen positioning image, on which there are positioning points; extracting the first coordinate position information of the positioning points on the screen positioning image; calculating the distortion coefficient based on the first coordinate position information of the positioning points on the screen positioning image and the second coordinate position information of the positioning points on the positioning screen; and correcting the pixel positions of the screen captured image after gray correction according to the distortion coefficient.

[0010] Optionally, the steps of extracting the pixel brightness information of the screen captured image after position correction to generate a brightness extraction result map include:

[0011] Preparing a mapping screen, using the mapping screen to light up the screen; using a sampling camera to capture an image of the screen to generate a screen mapping image; generating an affine transformation matrix based on the corner coordinate information of the screen mapping image and the target coordinate information of the screen captured image; and extracting the pixel brightness information of the screen captured image after position correction through the affine transformation matrix to generate a brightness extraction result map.

[0012] In a second aspect, an embodiment of the present application provides a device for screen brightness correction and extraction, including: a first generation unit for starting a standard light source and using a sampling camera to capture an image of the standard light source to generate a light source captured image; a second generation unit for designing a lighting image according to the standard light source, using the lighting image to light up the screen, and using a sampling camera to capture an image of the lit screen to generate a screen captured image; a segmentation unit for performing regional segmentation on the light source captured image and the screen captured image according to a preset segmentation accuracy to generate a number of corresponding segmentation regions on the light source captured image and the screen captured image; a brightness detection unit for using a luminance meter to detect the brightness of the segmentation regions on the light source captured image and the screen captured image; a calculation unit for calculating the gray mean data of the segmentation regions on the light source captured image and the screen captured image; a third generation unit for generating a correction coefficient based on the brightness data and the gray mean data of the segmentation regions; a first correction unit for correcting the screen captured image using the correction coefficient; a second correction unit for correcting the pixel positions of the screen captured image after gray correction; and a fourth generation unit for extracting the pixel brightness information of the screen captured image after position correction to generate a brightness extraction result map.

[0013] Optionally, the screen is a curved screen with a thin-film circuit added after the pixel layer. The curved screen includes a flat region and a curved region, and the thin-film circuit is located in the curved part of the screen body. The segmentation unit includes: determining the first flat region and the first curved region in the image captured by the screen; drawing the second flat region and the second curved region according to the positions corresponding to the first flat region and the first curved region in the image captured by the light source; performing region segmentation on the first flat region and the second flat region according to a preset first segmentation accuracy to generate a number of corresponding flat segmentation regions; performing region segmentation on the first curved region and the second curved region according to a preset second segmentation accuracy to generate a number of corresponding curved segmentation regions.

[0014] Optionally, after the brightness detection unit and before the calculation unit, the device further includes: a first acquisition unit, configured to acquire the curvature data and the pixel pitch data of the curved part of the screen, and generate vertical scattering degree data according to the curvature data and the pixel pitch data; a second acquisition unit, configured to acquire the reflectivity data of the thin-film circuit; a third correction unit, configured to perform curved surface brightness correction on the brightness data of the curved segmentation region of the screen according to the vertical scattering degree data and the reflectivity data.

[0015] Optionally, after the calculation unit and before the third generation unit, the device further includes: a fourth correction unit, configured to correct the curved surface gray level according to the reflectivity data of the thin-film circuit.

[0016] Optionally, the second correction unit includes: designing a positioning screen, using the positioning screen to light up the screen, with positioning points set on the positioning image, and the positions of the positioning points determined by the screen type; using a sampling camera to capture an image of the screen to generate a screen positioning image, on which there are positioning points; extracting the first coordinate position information of the positioning points on the screen positioning image; calculating the distortion coefficient according to the first coordinate position information of the positioning points on the screen positioning image and the second coordinate position information of the positioning points on the positioning screen; performing pixel position correction on the gray level corrected screen captured image according to the distortion coefficient.

[0017] Optionally, the fourth generation unit includes: preparing a mapping screen, using the mapping screen to light up the screen; using a sampling camera to capture an image of the screen to generate a screen mapping image; generating an affine transformation matrix according to the corner coordinate information of the screen mapping image and the target coordinate information of the screen captured image; extracting the pixel brightness information of the screen captured image with the position correction completed through the affine transformation matrix to generate a brightness extraction result image.

[0018] In a third aspect, an embodiment of the present application provides a device for extracting screen brightness correction, including: a processor, a memory, an input / output unit, and a bus; the processor is connected to the memory, the input / output unit, and the bus; the memory stores a program, and the processor calls the program to execute the methods as described in the first aspect and any optional methods of the first aspect.

[0019] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, on which a program is stored, and when the program is executed on a computer, it executes the methods as described in the first aspect and any optional methods of the first aspect.

[0020] It can be seen from the above technical solutions that the embodiments of the present application have the following advantages:

[0021] The present application first activates a standard light source, uses a sampling camera to collect an image of the standard light source to generate a light source captured image. Designs a lighting image according to the standard light source, uses the lighting image to light up the screen, and uses the sampling camera to collect an image of the lit screen to generate a screen captured image. Performs region segmentation on the light source captured image and the screen captured image according to a preset segmentation accuracy, and generates a number of corresponding segmentation regions on the light source captured image and the screen captured image. Uses a luminance meter to detect the brightness of the segmentation regions on the light source captured image and the screen captured image. Calculates the grayscale mean data of the segmentation regions on the light source captured image and the screen captured image. Generates a correction coefficient according to the brightness data and the grayscale mean data of the segmentation regions. Uses the correction coefficient to correct the image of the screen captured image. Performs pixel position correction on the grayscale-corrected screen captured image. Extracts the pixel brightness information of the screen captured image after the position correction is completed to generate a brightness extraction result image.

[0022] By lighting up the standard light source and the screen, then using a sampling camera to take pictures to generate a screen captured image and a light source captured image, then performing region segmentation on the screen captured image and the light source captured image, and then using a luminance meter for brightness detection, and combining the grayscale detection data for brightness correction to make the brightness performance of the screen center and the edge in the screen captured image consistent, and then performing a partition position correction on the overall screen once, and then extracting the brightness of all lit pixels, this method can not only ensure the extraction position accuracy, but also avoid multiple search and extraction and merging operations, further improving the accuracy of brightness extraction. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0024] Figure 1 Schematic diagram of an embodiment of the method for extracting screen brightness correction of the present application;

[0025] Figure 2 Schematic diagram of an embodiment of the method for image region segmentation of the present application;

[0026] Figure 3 Schematic diagram of an embodiment of the method for curved surface brightness correction of the present application;

[0027] Figure 4 Schematic diagram of an embodiment of the method for curved surface gray level correction of the present application;

[0028] Figure 5 Schematic diagram of an embodiment of the method for pixel position correction of the present application;

[0029] Figure 6 Schematic diagram of an embodiment of the method for generating a brightness extraction result map of the present application;

[0030] Figure 7 Schematic diagram of an embodiment of the device for extracting screen brightness correction of the present application;

[0031] Figure 8 Schematic diagram of another embodiment of the device for extracting screen brightness correction of the present application;

[0032] Figure 9 Schematic diagram of an embodiment of the screen capture of the present application;

[0033] Figure 10 Schematic diagram of an embodiment of the screen positioning image of the flat panel display of the present application;

[0034] Figure 11 Schematic diagram of an embodiment of the image after positioning processing of the screen positioning image of the flat panel display of the present application;

[0035] Figure 12 Schematic diagram of an embodiment of the brightness extraction result map corresponding to the screen capture image of the present application. Detailed implementation manners

[0036] In the following description, specific details such as specific system architectures and technologies are presented for the purpose of illustration rather than limitation, so as to thoroughly understand the embodiments of the present application. However, those skilled in the art should clearly understand that the present application can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid unnecessary details from interfering with the description of the present application.

[0037] It should be understood that, as used in the specification of this application and the appended claims, the term "comprising" indicates the presence of the described features, integers, steps, operations, elements, and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or their groups.

[0038] It should also be understood that the term "and / or" as used in the specification of this application and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0039] As used in the specification of this application and the appended claims, the term "if" can be construed, depending on the context, as "when" or "once" or "in response to determining" or "in response to detecting". Similarly, the phrases "if determined" or "if [the described condition or event] is detected" can be construed, depending on the context, as meaning "once determined" or "in response to determining" or "once [the described condition or event] is detected" or "in response to detecting [the described condition or event]".

[0040] In addition, in the description of the specification of this application and the appended claims, the terms "first", "second", "third", etc. are used only for descriptive distinction and should not be construed as indicating or implying relative importance.

[0041] Reference to "one embodiment" or "some embodiments" or the like described in the specification of this application means that a particular feature, structure, or characteristic described in connection with that embodiment is included in one or more embodiments of this application. Thus, statements such as "in one embodiment", "in some embodiments", "in other some embodiments", "in still other embodiments", etc. that appear in different places in this specification are not necessarily all referring to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in another way. The terms "comprising", "including", "having", and their variants all mean "including but not limited to", unless otherwise specifically emphasized in another way.

[0042] In the prior art, there are still many problems in the process of brightness extraction. First, in the continuous update and iteration process of the display screen, various new types of screens such as curved screens and folding screens have emerged. And in order to increase the functionality of the display screen, on the basis of adding a PCB structure under the original display screen, a thin-film circuit is also selected to be added under the pixel layer of the display screen. The thin-film circuit is used to control the structure on the pixel layer. Such a thin-film circuit has a certain reflection ability, which will affect the brightness of the display screen, and thus affect the brightness extraction of the display screen. Such a circuit structure is usually set at the bottom edge part of the display screen because the display function in this part of the area allows a certain brightness error. Second, due to the characteristics of the optical FA lens of the acquisition camera, when the display screen product is relatively large, it is also easy to have a situation where there is a difference in the collected brightness between the center and the edge of the product. This makes it more difficult to extract the brightness of the edge part of the display screen, reducing the accuracy of pixel brightness extraction.

[0043] Based on this, the present application discloses a method, device and storage medium for screen brightness correction and extraction, which are used to improve the accuracy of pixel brightness extraction.

[0044] Next, the technical solutions in the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present application.

[0045] The method of the present application can be applied to a server, a device, a terminal or other devices with logical processing capabilities. In this regard, the present application makes no limitation. For the sake of convenience of description, the following takes the execution subject as a terminal as an example for description.

[0046] Please refer to Figure 1 , an embodiment of a method for screen brightness correction and extraction provided by the present application includes:

[0047] 101. Start a standard light source, use a sampling camera to collect an image of the standard light source, and generate a light source captured image.

[0048] 102. Design a lighting image according to the standard light source, use the lighting image to light the screen, and use a sampling camera to collect an image of the lit screen, and generate a screen captured image.

[0049] 103. Perform region segmentation on the light source captured image and the screen captured image according to a preset segmentation accuracy, and generate a number of corresponding segmentation regions on the light source captured image and the screen captured image.

[0050] 104. Use a luminance meter to detect the luminance of the segmented areas on the light source captured image and the screen captured image.

[0051] 105. Calculate the grayscale mean data of the segmented areas on the light source captured image and the screen captured image.

[0052] 106. Generate a correction coefficient based on the luminance data and grayscale mean data of the segmented areas.

[0053] 107. Use the correction coefficient to correct the screen captured image.

[0054] 108. Perform pixel position correction on the screen captured image after grayscale correction.

[0055] 109. Extract the pixel luminance information from the screen captured image after position correction is completed to generate a luminance extraction result image.

[0056] In the embodiments of the present application, a set of standard light sources are used as a reference system, and generally a spherical integrating light source is selected. Under the standard light source, an acquisition camera is used for shooting to generate a light source captured image. Then, the screen is lit to display a lit screen, and then a sampling camera is used to collect an image of the lit screen to generate a screen captured image. After shooting, the segmentation accuracy is set, and according to the preset segmentation accuracy, the light source captured image and the screen captured image are regionally segmented, and a number of corresponding segmented areas are generated on the light source captured image and the screen captured image. The segmentation accuracy is generated according to the type of the screen, such as a flat area, a curved surface area, a folding area, etc., and a number of rectangular areas centered on the camera central axis, and also includes the corresponding areas of the thin-film circuits provided in the screen. Because the brightness of different areas is affected differently, it is necessary to perform separate corrections on different affected areas through regional segmentation. Please view Figure 9 , Figure 9 is a schematic diagram of a screen captured image. All the pixels of the lit screen are lit, but there will be differences in the luminance and grayscale of the pixels on the screen captured image.

[0057] Next, the terminal uses a luminance meter as the acquisition luminance reference, and in this embodiment, a CS2000 luminance meter is used for detection.

[0058] After the terminal has captured the light source captured image and the screen captured image, the light source captured image and the screen captured image are correspondingly segmented into N areas. The segmentation methods of the two images are the same. Generally, the curved surface area, the circuit area, etc. are first segmented according to the screen captured image, and then the light source captured image is segmented in the same way according to the segmentation method. The correction coefficient is calculated for each area, and each correction coefficient K is obtained. It should be noted that the larger the number N of the segmented areas, the higher the accuracy, but the processing time will also be longer.

[0059] Next, the terminal calculates the grayscale mean data of the segmented regions on the light source captured image and the screen captured image, and generates a correction coefficient based on the brightness data and the grayscale mean data of the segmented regions.

[0060]

[0061] Among them, is the brightness value measured by CS2000 for the light source captured image under the standard light source, is the brightness value measured by CS2000 for the screen captured image; is the average grayscale of the corresponding unit comparison region in the light source captured image of the standard light source; is the average grayscale of the corresponding unit comparison region in the image to be corrected (screen captured image).

[0062] The terminal calculates the correction coefficient K according to the segmentation accuracy, and then corrects the screen captured image. The correction formula is as follows.

[0063]

[0064] I is the correction region of the screen captured image, is the grayscale of the corrected image.

[0065] In the embodiment of the present application, the standard light source is first started, and the sampling camera is used to collect an image of the standard light source to generate a light source captured image. According to the standard light source, a lighting image is designed, the screen is lit with the lighting image, and the sampling camera is used to collect an image of the lit screen to generate a screen captured image. According to the preset segmentation accuracy, the light source captured image and the screen captured image are regionally segmented, and a number of corresponding segmented regions are generated on the light source captured image and the screen captured image. The brightness of the segmented regions on the light source captured image and the screen captured image is detected using a luminance meter. The grayscale mean data of the segmented regions on the light source captured image and the screen captured image is calculated. A correction coefficient is generated based on the brightness data and the grayscale mean data of the segmented regions. The screen captured image is image-corrected using the correction coefficient. Pixel position correction is performed on the screen captured image after grayscale correction. Pixel brightness information extraction is performed on the screen captured image after position correction is completed to generate a brightness extraction result image.

[0066] By lighting a standard light source and a screen, then using a sampling camera to take pictures, generating a screen captured image and a light source captured image, then performing region segmentation on the screen captured image and the light source captured image, and then using a luminance meter to perform luminance detection, and combining the gray-scale detection data to perform luminance correction to make the luminance performance of the screen center and the edge in the screen captured image consistent, and then performing a partition position correction on the overall screen once, and then extracting the luminance of all fully lit pixel points. This method can not only ensure the position accuracy of the extraction, but also avoid the operations of multiple searches, extractions, and merges, and further improve the accuracy of luminance extraction.

[0067] Please refer to Figure 2 , this application provides an embodiment of a method for image region segmentation. The screen is a curved screen with a thin-film circuit added after the pixel layer. The curved screen includes a planar region and a curved region. The thin-film circuit is located on the curved part of the screen body and includes:

[0068] 201. Determine the first planar region and the first curved region in the screen captured image.

[0069] 202. Draw the second planar region and the second curved region according to the corresponding positions of the first planar region and the first curved region on the light source captured image.

[0070] 203. Perform region segmentation on the first planar region and the second planar region according to a preset first segmentation accuracy to generate a number of corresponding planar segmentation regions.

[0071] 204. Perform region segmentation on the first curved region and the second curved region according to a preset second segmentation accuracy to generate a number of corresponding curved segmentation regions.

[0072] In the embodiments of the present application, it is applicable to a new type of curved screen. This type of curved screen is provided with a thin-film circuit, which is different from the conventional setting scheme. A display screen is composed of multiple structural layers stacked together. After production, the operation of each structural layer on the display screen is controlled by a crimping method. When all aspects of the display screen are qualified, the display screen can be integrated with structures such as a PCB board to form a device with a display function. The conventional thin-film circuit layer, as one of the layers in the display screen structure, is usually arranged below the pixel layer of a flat display screen. In the thin-film circuit layer, the thin-film circuit may not occupy the entire layer because there are many metal lines for transmitting electrical signals. Therefore, in order to reduce the influence of the thin-film circuit, the wave circuit is usually selected to be arranged at the edge of the thin-film circuit layer. For example: a touchable screen applied to a mobile phone has a large display area in the middle of the screen, and the bottom edge is usually the button area of the touch screen. Although this area can also display the picture normally, for users, the importance of the display function in this area is not as high as that of the central display area, that is, the display quality of this area (for users) can be slightly lower than that of the central area. Therefore, the thin-film circuit is usually arranged at the lower edge of the thin-film circuit layer. However, with the emergence of curved screens, for users, the importance of the curved part to the display function is significantly lower than that of the lower edge of the display screen. Therefore, the current strategy is usually to arrange the thin-film circuit in the curved part of the thin-film circuit layer. However, the curved part of the curved screen requires high-precision pixel point information extraction during the detection process, which requires detection by new technical means.

[0073] In the embodiment of the present application, the terminal first determines the first planar region and the first curved surface region in the screen capture image, that is, divides different calibration regions. Then, according to the positions of the first planar region and the first curved surface region corresponding to them in the light source capture image, the second planar region and the second curved surface region are drawn, because the calculation of subsequent calibration parameters needs to be performed based on the grayscale and brightness of the corresponding regions of the two images. Next, the first planar region and the second planar region are segmented according to a preset first segmentation accuracy to generate a number of corresponding planar segmentation regions, and the first curved surface region and the second curved surface region are segmented according to a preset second segmentation accuracy to generate a number of corresponding curved surface segmentation regions. Since the curved surface region requires higher accuracy, and the pixel points on the planar region can usually be collected by the sampling line camera, while only part of the curved surface part can be captured. When the camera shoots vertically from top to bottom, only the pixel points in the part perpendicular to the front can be collected, and this part is usually located at the edge. In order to capture all the pixel points of the curved surface part, the prism reflection method is usually used for collection, that is, two reflection prisms are placed on both sides of the curved surface screen, which can reflect the pixel points on the back to the camera. However, this will make the sampling of a part of the curved surface region farther from the center of the collection camera, and the subsequent brightness extraction is more susceptible to the influence of the lens and the thin film circuit. Therefore, it is necessary to segment the complete curved surface part (the part collected by the prism reflection method) of the screen capture image and perform the same segmentation on the corresponding part of the light source capture image, so as to increase the accuracy in the subsequent brightness extraction process.

[0074] Please refer to Figure 3 , an embodiment of a method for correcting the brightness of a curved surface provided by the present application includes:

[0075] 301. Obtain the curvature data and pixel point spacing data of the curved surface part of the screen, and generate vertical scattering degree data according to the curvature data and pixel point spacing data.

[0076] 302. Obtain the reflectivity data of the thin film circuit.

[0077] 303. Perform curved surface brightness correction on the brightness data of the curved surface segmentation region of the screen according to the vertical scattering degree data and the reflectivity data.

[0078] In the embodiment of the present application, the terminal needs to correct the brightness of the curved surface part of the curved surface screen. Although the brightness of the image is extracted by a brightness meter, it cannot be guaranteed that it is the same as the actual display of the display screen. Therefore, pre-brightness correction processing is required.

[0079] In an embodiment of the present application, a brightness pre - correction method for a curved screen with an overlaid thin - film circuit layer is disclosed. The method obtains the curvature data and pixel - point pitch data of the curved part of the screen. The curvature data represents the bending - degree parameter of the curved part, and this parameter can be set and measured during design. The bending degree can affect the light - emitting direction of pixel points, resulting in differences in the brightness collected by a sampling camera for vertical shooting.

[0080] The pixel - point pitch data refers to the distance between two adjacent pixel points among the pixel points of the curved part. For any two adjacent pixel points in the curved - surface area of the curved screen in the embodiment of the present application, the distance is the same, but it may be different from that of the flat part.

[0081] The terminal generates vertical - scattering - degree data according to the curvature data and pixel - point pitch data. The vertical - scattering - degree data represents the loss degree of pixel points in the acquisition direction (vertically upward). First, according to the curvature data and pixel - point pitch data look up a table or calculate to generate a curvature - scattering parameter , because the brightness changes caused by different bending degrees and pixel - point pitches are different. Specifically, the curvature - scattering parameter can be obtained by collecting the parameters of the brightness of the curved - surface area and the flat - surface area of different curved screens, as well as the curvature and pixel - point pitch data. Calculate the curvature - scattering parameter through the ratio of the flat - surface area brightness to the curved - surface area brightness. Next, generate a corresponding query table. Then, only according to the curvature data and pixel - point pitch data of the subsequent - detected curved screen, and then query the curvature - scattering parameter from the table where is greater than 0 and less than 1.

[0082] Next, the terminal obtains the reflectivity data of the thin - film circuit. Due to the high integration of the thin - film circuit and it being mainly composed of metal, there is a reflection of the light emitted by pixel points on the pixel layer. Therefore, before production, the reflectivity of the thin - film circuit is detected to generate corresponding reflectivity data.

[0083] Next, the terminal performs curved - surface brightness correction on the brightness data of the curved - surface segmentation area of the screen according to the vertical - scattering - degree data and reflectivity data. The formula for the curved - surface brightness - correction coefficient is as follows:

[0084]

[0085]

[0086] where is the brightness after curved - surface brightness correction, is the brightness before curved - surface brightness correction, Reflectivity data of the thin-film circuit. This method can accurately correct the brightness of the curved surface part and the thin-film circuit part. For the normal curved surface area, the traditional correction method can be used.

[0087] Please refer to Figure 4 , this application provides an embodiment of a method for curved surface gray correction, including:

[0088] 401. Correct the curved surface gray level according to the reflectivity data of the thin-film circuit.

[0089] In this embodiment, the curved surface gray level is the gray level average value of the curved surface area in the gray level average data, and only the divided area where the circuit area exists needs to be adjusted, that is, the area where the curved surface area and the thin-film circuit area overlap. After obtaining the curved surface gray level of this part, corresponding correction is performed. Since the thin-film circuit has a greater impact on the curved surface gray level, it is necessary to try to use the reflectivity data for correction. The curved surface gray level is a gray level average value, specifically the gray level average value of the R, G, and B channels. However, this application only corrects the gray level of channel G because this channel has the greatest impact on the human eye.

[0090]

[0091] After re-correcting the gray level of channel G, the gray levels of the R, G, and B channels are averaged. This processing can well handle the influence of the curved surface area and the circuit area, making the subsequent correction more accurate.

[0092] Please refer to Figure 5 , this application provides an embodiment of a method for pixel position correction, including:

[0093] 501. Design a positioning screen, use the positioning screen to light up the screen. There are positioning points on the positioning image, and the positions of the positioning points are determined by the screen type.

[0094] 502. Use a sampling camera to collect images of the screen to generate a screen positioning image, and there are positioning points on the screen positioning image.

[0095] 503. Extract the first coordinate position information of the positioning points on the screen positioning image.

[0096] 504. Calculate the distortion coefficient according to the first coordinate position information of the positioning points on the screen positioning image and the second coordinate position information of the positioning points on the positioning screen.

[0097] 505. Perform pixel position correction on the screen captured image after gray correction according to the distortion coefficient.

[0098] In this embodiment, the terminal designs a positioning screen, uses the positioning screen to light up the screen, and a mark positioning point is set on the positioning image. The position of the mark positioning point is determined by the screen type.

[0099] The terminal uses a sampling camera to collect an image of the screen, generating a screen positioning image with positioning points on it. Please refer to Figure 10 , Figure 10 Figure 7 is a schematic diagram of the screen positioning image of a flat panel display. The shooting center in the figure is biased to the right. It can be seen that the part at the edge is relatively blurred, and the part at the center of the camera is relatively clear. There is an obvious difference in the brightness of the positioning points.

[0100] The terminal extracts the first coordinate position information of the positioning points on the screen positioning image, performs threshold segmentation on the captured screen positioning image, then disconnects the connected regions of the selected area, and extracts the corresponding first coordinate position information by screening the shape and pixel area. Please refer to Figure 11 , Figure 11 Figure 14 is a schematic diagram of the image after positioning processing of the screen positioning image of a flat panel display. The position circled in red is the first coordinate position information after positioning is completed.

[0101] Next, the terminal calculates the distortion coefficient based on the first coordinate position information of the positioning points on the screen positioning image and the second coordinate position information of the positioning points on the positioning screen. Finally, the pixel position of the grayscale-corrected screen captured image is corrected according to the distortion coefficient. Calculating the distortion coefficient includes the expressions of the radial distortion coefficient and the tangential distortion coefficient:

[0102] The expression of the radial distortion coefficient is:

[0103]

[0104]

[0105] Among them, Xdr and Ydr are the distorted pixel coordinates, x and y are the ideal coordinates. x and y have the following equations. r is the value calculated from the ideal coordinates, which is the distance of the target point from the center. k1, k2, and k3 are the radial distortion parameters.

[0106]

[0107] The expression of the tangential distortion coefficient is:

[0108]

[0109]

[0110] Among them, Xdt and Ydt are also the distorted pixel coordinates, x and y are the ideal coordinates, and p1 and p2 are the tangential distortion parameters.

[0111] It can be seen that five distortion coefficients k1, k2, k3, p1, and p2 need to be solved.

[0112] The solution is obtained through the following polynomial:

[0113]

[0114]

[0115] Solve the polynomial equation to find the five distortion coefficients k1, k2, k3, p1, and p2.

[0116] Where Delta_x is the ideal column coordinate, Delta_y is the ideal row coordinate, x = grid reference map mark column coordinate * MR - actual map mark column coordinate, y = grid reference map mark row coordinate * MR - actual map mark row coordinate. The grid reference map mark is the positioning screen, the actual map is the screen positioning image, and MR is how many image pixels a single screen pixel occupies in the corresponding image.

[0117] Please refer to Figure 6 , an embodiment of a method for generating a luminance extraction result map provided by this application includes:

[0118] 601. Prepare a mapping screen and use the mapping screen to light up the screen.

[0119] 602. Use a sampling camera to collect an image of the screen to generate a screen mapping image.

[0120] 603. Generate an affine transformation matrix based on the corner coordinate information of the screen mapping image and the target coordinate information of the screen captured image.

[0121] 604. Extract the pixel point luminance information from the screen captured image with position correction completed through the affine transformation matrix to generate a luminance extraction result map.

[0122] In the embodiment of this application, the terminal prepares a mapping screen and uses the mapping screen to light up the screen. Use a sampling camera to collect an image of the screen to generate a screen mapping image. Generate an affine transformation matrix based on the corner coordinate information of the screen mapping image and the target coordinate information of the screen captured image. Extract the pixel point luminance information from the screen captured image with position correction completed through the affine transformation matrix to generate a luminance extraction result map. Specifically, the terminal needs to perform luminance extraction on the corrected screen captured image to form a small image. It is necessary to calculate the mapping matrix from the screen captured image to the small image to obtain the extracted luminance extraction result map.

[0123] First, create a mapping screen with a resolution equal to the screen resolution and a grayscale of 255. Import the PG device so that the display screen shows the mapping screen and take a photo with the acquisition camera to obtain the screen mapping image.

[0124] Extract the screen area of the screen mapping image to obtain the corner point coordinate set A, and calculate the required affine transformation matrix C through the corresponding target coordinates B on the screen capture image.

[0125]

[0126] The matrix is expanded as follows:

[0127]

[0128] Where QX and QY are the target coordinates B, that is, all the point coordinates of the brightness extraction result map: (0,0), (0,1)...(0,PixelCol), (1,0)...(1,PixelCol)...(PixelRow,PixelCol),

[0129] PX and PY are the coordinates of the captured image array.

[0130]

[0131] Where MR represents how many image pixels a single screen pixel occupies in the image, PixelRow is the resolution in the screen row direction, and PixelCol is the resolution in the screen column direction.

[0132] After obtaining the affine transformation matrix C, perform a transformation on the screen capture image to obtain the brightness extraction result map. Please refer to Figure 12 , Figure 12 is the brightness extraction result map corresponding to the screen capture image.

[0133] Please refer to Figure 7 , this application provides an embodiment of a device for screen brightness correction and extraction, including:

[0134] The first generation unit 701 is used to start the standard light source, collect images of the standard light source using the sampling camera, and generate a light source capture image.

[0135] The second generation unit 702 is used to design a lighting image according to the standard light source, light the screen with the lighting image, and collect images of the lit screen using the sampling camera to generate a screen capture image.

[0136] The segmentation unit 703 is used to perform regional segmentation on the light source capture image and the screen capture image according to the preset segmentation accuracy, and generate a number of corresponding segmentation regions on the light source capture image and the screen capture image.

[0137] Optionally, the screen is a curved screen with a thin-film circuit added after the pixel layer. The curved screen includes a flat area and a curved area, and the thin-film circuit is located in the curved part of the screen body.

[0138] The segmentation unit 703 includes:

[0139] Determine the first flat area and the first curved area in the screen captured image.

[0140] Draw the second flat area and the second curved area according to the positions corresponding to the first flat area and the first curved area on the light source captured image.

[0141] Perform region segmentation on the first flat area and the second flat area according to the preset first segmentation accuracy to generate a number of corresponding flat segmentation regions.

[0142] Perform region segmentation on the first curved area and the second curved area according to the preset second segmentation accuracy to generate a number of corresponding curved segmentation regions.

[0143] The brightness detection unit 704 is used to detect the brightness of the segmented regions on the light source captured image and the screen captured image using a luminance meter.

[0144] The first acquisition unit 705 is used to acquire the curvature data and pixel pitch data of the curved part of the screen, and generate vertical scattering degree data according to the curvature data and pixel pitch data.

[0145] The second acquisition unit 706 is used to acquire the reflectivity data of the thin-film circuit.

[0146] The third correction unit 707 is used to perform curved surface brightness correction on the brightness data of the curved surface segmented regions of the screen according to the vertical scattering degree data and the reflectivity data.

[0147] The calculation unit 708 is used to calculate the grayscale mean data of the segmented regions on the light source captured image and the screen captured image.

[0148] The fourth correction unit 709 is used to correct the curved surface grayscale according to the reflectivity data of the thin-film circuit.

[0149] The third generation unit 710 is used to generate a correction coefficient according to the brightness data and the grayscale mean data of the segmented regions.

[0150] The first correction unit 711 is used to perform image correction on the screen captured image using the correction coefficient.

[0151] The second correction unit 712 is used to perform pixel position correction on the screen captured image after grayscale correction.

[0152] Optionally, the second correction unit 712 includes:

[0153] Design a positioning screen, use the positioning screen to light up the screen, and positioning points are set on the positioning image, and the positions of the positioning points are determined by the screen type.

[0154] Use a sampling camera to collect images of the screen to generate a screen positioning image, and there are positioning points on the screen positioning image.

[0155] Extract the first coordinate position information of the positioning points on the screen positioning image.

[0156] Calculate the distortion coefficient according to the first coordinate position information of the positioning points on the screen positioning image and the second coordinate position information of the positioning points on the positioning screen.

[0157] Perform pixel position correction on the screen captured image after gray correction according to the distortion coefficient.

[0158] The fourth generation unit 713 is used to extract the pixel brightness information of the screen captured image after the position correction is completed to generate a brightness extraction result map.

[0159] Optionally, the fourth generation unit 713 includes:

[0160] Prepare a mapping screen and use the mapping screen to light up the screen.

[0161] Use a sampling camera to collect images of the screen to generate a screen mapping image.

[0162] Generate an affine transformation matrix according to the corner coordinate information of the screen mapping image and the target coordinate information of the screen captured image.

[0163] Extract the pixel brightness information of the screen captured image after the position correction is completed through the affine transformation matrix to generate a brightness extraction result map.

[0164] Please refer to Figure 8 , this application provides a device for screen brightness correction and extraction, including:

[0165] A processor 801, a memory 802, an input / output unit 803, and a bus 804.

[0166] The processor 801 is connected to the memory 802, the input / output unit 803, and the bus 804.

[0167] The memory 802 stores a program, and the processor 801 calls the program to execute the methods as described in Figure 1 , Figure 2 and Figure 3 , Figure 4 , Figure 5 , Figure 6 in the method.

[0168] This application provides a computer-readable storage medium, on which a program is stored. When the program is executed on a computer, it executes the methods such as Figure 1 , Figure 2 and Figure 3 , Figure 4 , Figure 5 , Figure 6 in it.

[0169] Those skilled in the art can clearly understand that for the convenience and conciseness of description, the specific working processes of the above-described systems, devices, and units can refer to the corresponding processes in the foregoing method embodiments, and will not be described herein again.

[0170] In several embodiments provided by this application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed mutual coupling or direct coupling or communication connection can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be in electrical, mechanical or other forms.

[0171] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they can be located in one place, or can be distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiments of this application.

[0172] In addition, the functional units in each embodiment of this application can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units.

[0173] When the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of this application. The foregoing storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROM, read-only memory), random access memories (RAM, random access memory), magnetic disks, or optical discs.

Claims

1. A method for screen brightness correction extraction, characterized in that: include: Starting a standard light source, using a sampling camera to collect images of the standard light source, and generating a light source shooting image; Design a lighting image according to a standard light source, light up the screen using the lighting image, and use a sampling camera to collect an image of the lit screen to generate a screen shot image; Performing regional segmentation on the light source captured image and the screen captured image according to a preset segmentation accuracy, and generating a plurality of one-to-one corresponding segmentation regions on the light source captured image and the screen captured image; Using a brightness meter to detect the brightness of the divided areas on the light source captured image and the screen captured image; Calculating grayscale mean data of segmented areas on the light source captured image and the screen captured image; Generate correction coefficients based on brightness data and grayscale mean data of the segmented area; Performing image correction on the screen captured image using the correction coefficient; Performing pixel point position correction on the screen captured image after grayscale correction; Pixel brightness information is extracted from the position-corrected screen shot image to generate a brightness extraction result graph.

2. The method according to claim 1, characterized in that The screen is a curved screen with a thin-film circuit added behind the pixel layer, the curved screen includes a flat area and a curved area, and the thin-film circuit is located on the curved surface of the screen body; The step of segmenting the light source captured image and the screen captured image according to a preset segmentation accuracy and generating a plurality of one-to-one corresponding segmentation areas on the light source captured image and the screen captured image comprises: Determining a first plane area and a first curved surface area in the screen shot image; Draw a second plane area and a second curved surface area according to corresponding positions of the first plane area and the first curved surface area on the image captured by the light source; Performing region segmentation on the first plane region and the second plane region according to a preset first segmentation accuracy to generate a plurality of one-to-one corresponding plane segmentation regions; The first curved surface region and the second curved surface region are segmented according to a preset second segmentation accuracy to generate a plurality of one-to-one corresponding curved surface segmentation regions.

3. The method according to claim 2, characterized in that After the step of using a luminance meter to detect the brightness of the segmented areas on the light source captured image and the screen captured image, and before the step of calculating grayscale mean data of the segmented areas on the light source captured image and the screen captured image, the method further includes: Acquire curvature data and pixel spacing data of a curved surface portion of the screen, and generate vertical scattering data according to the curvature data and the pixel spacing data; Obtaining reflectivity data of a thin-film circuit; The curved surface brightness correction is performed on the brightness data of the curved surface segmented area of ​​the screen according to the vertical scattering degree data and the reflectivity data.

4. The method according to claim 3, characterized in that After the step of calculating the grayscale mean data of the segmented areas on the light source captured image and the screen captured image, and before generating the correction coefficients according to the brightness data and grayscale mean data of the segmented areas, the method further includes: The grayscale of the curved surface is corrected according to the reflectivity data of the thin film circuit.

5. The method according to any one of claims 1 to 4, characterized in that The step of performing pixel point position correction on the grayscale-corrected screen captured image comprises: Design a positioning screen, and use the positioning screen to light up the screen. The positioning screen is provided with positioning points, and the positions of the positioning points are determined by the screen type; Using a sampling camera to collect images of the screen to generate a screen positioning image, wherein the screen positioning image has positioning points; Extracting first coordinate position information of the positioning point on the screen positioning image; Calculating a distortion coefficient according to first coordinate position information of a positioning point on the screen positioning image and second coordinate position information of a positioning point on the positioning picture; The pixel position of the screen shot image after grayscale correction is corrected according to the distortion coefficient.

6. The method according to any one of claims 1 to 4, characterized in that The step of extracting pixel brightness information from the screen shot image after position correction to generate a brightness extraction result map comprises: Prepare a mapping picture, and use the mapping picture to light up the screen; Use a sampling camera to collect images of the screen and generate a screen mapping image; generating an affine transformation matrix according to the corner point coordinate information of the screen mapping image and the target coordinate information of the screen capturing image; The affine transformation matrix is ​​used to extract the pixel brightness information of the screen shot image after position correction, and a brightness extraction result map is generated.

7. A device for screen brightness correction extraction, characterized in that: include: A first generating unit is used to start a standard light source, use a sampling camera to collect images of the standard light source, and generate a light source shooting image; A second generating unit is used to design a lighting image according to a standard light source, light up a screen using the lighting image, and use a sampling camera to collect an image of the lit screen to generate a screen shot image; a segmentation unit, configured to perform region segmentation on the light source captured image and the screen captured image according to a preset segmentation accuracy, and generate a plurality of one-to-one corresponding segmentation regions on the light source captured image and the screen captured image; a brightness detection unit, configured to use a brightness meter to detect brightness of the divided areas on the light source captured image and the screen captured image; A calculation unit, used for calculating grayscale mean data of segmented areas on the light source captured image and the screen captured image; A third generating unit, used for generating a correction coefficient according to the brightness data and grayscale mean data of the segmented area; A first correction unit, configured to perform image correction on the screen captured image using the correction coefficient; A second correction unit, used for performing pixel point position correction on the screen captured image after grayscale correction; The fourth generating unit is used to extract the brightness information of the pixels of the screen shot image after the position correction, and generate a brightness extraction result map.

8. The device according to claim 7, characterized in that The screen is a curved screen with a thin-film circuit added behind the pixel layer, the curved screen includes a flat area and a curved area, and the thin-film circuit is located on the curved surface of the screen body; The segmentation unit comprises: Determining a first plane area and a first curved surface area in the screen shot image; Draw a second plane area and a second curved surface area according to corresponding positions of the first plane area and the first curved surface area on the image captured by the light source; Performing region segmentation on the first plane region and the second plane region according to a preset first segmentation accuracy to generate a plurality of one-to-one corresponding plane segmentation regions; The first curved surface region and the second curved surface region are segmented according to a preset second segmentation accuracy to generate a plurality of one-to-one corresponding curved surface segmentation regions.

9. The device according to claim 8, characterized in that The device also includes: A first acquisition unit, used to acquire curvature data and pixel spacing data of a curved surface portion of the screen, and generate vertical scattering data according to the curvature data and the pixel spacing data; A second acquisition unit, used to acquire reflectivity data of the thin-sheet circuit; The third correction unit is used to perform curved surface brightness correction on the brightness data of the curved surface segmented area of ​​the screen according to the vertical scattering data and the reflectivity data.

10. A computer-readable storage medium having a program stored thereon, wherein the program, when executed on a computer, performs the method according to any one of claims 1 to 6.

Images