Method, apparatus and display screen control device for evaluating / correcting a display screen

Abstract

Provided are a method, device and system for evaluating / correcting an LED display screen. The method comprises: controlling all target light points in part or all display areas of the LED display screen to be in a lighting state, so as to non-segmentedly collect imaging of the target light points; adjusting camera parameters on an image preview interface of the camera, so that the imaging of the target light points is in a sticking state; controlling the camera to capture the LED display screen, so as to obtain a light point image corresponding to the target light points; and obtaining evaluation information and / or correction information of the LED display screen according to the light point image. The above technical solution can improve the evaluation and / or correction efficiency of the LED display screen.

Description

Technical Field

[0001] This application relates to the field of LED display technology, and more specifically, to a method, apparatus, and system for evaluating / calibrating LED displays. Background Technology

[0002] Due to factors such as manufacturing errors or usage time, LED displays often require evaluation and / or calibration. Before evaluating and / or calibrating an LED display, it is typically necessary to photograph the LED lights using a camera, and then obtain evaluation and / or calibration information based on these images. How to perform efficient and accurate evaluation / calibration of LED displays is a problem that urgently needs to be solved. Summary of the Invention

[0003] With the development of technology, the number of LED lights in LED displays is constantly increasing. Due to the limited pixels of cameras, it is difficult for cameras to capture all the lights on a large screen at once. Therefore, many related technologies control the LED display to light up at intervals, thereby capturing the LED light images at intervals (this solution will be referred to as the interval solution below, and the non-interval solution is the opposite of the interval solution).

[0004] However, with the continuous reduction in the spacing between LED dots in LED displays, especially with the emergence of miniLED and microLED, the coupling phenomenon between the dots has become increasingly obvious. This results in significant differences in the mura morphology of the dots under spaced-out and non-spaced-out lighting conditions (mura can be understood as various traces caused by uneven display in LED displays). In this situation, the inventors discovered that the evaluation / calibration results of LED displays using a spaced-out method are often inaccurate, and a non-spaced-out method should be used instead.

[0005] This embodiment of the application, based on the non-interlaced-dot scheme, adjusts the camera parameters in the camera's image preview interface, causing the LED dots within the LED display screen to appear as a continuous image at the camera's location. Because the LED dots are in a continuous image state, the camera can capture a larger display area of ​​the LED display screen at once, thereby improving the evaluation and / or calibration efficiency of the LED display screen.

[0006] The following is a description of the various aspects involved in this application.

[0007] In a first aspect, a method for evaluating / calibrating an LED display screen is provided, comprising: controlling all target LEDs within part or all of the display area of ​​the LED display screen to be illuminated, so as to perform non-interlaced acquisition of the image of the target LEDs, wherein the target LEDs are one or more combinations of red, green, and blue LEDs; adjusting the camera parameters of a camera so that the image of the target LEDs is in a connected state, the connected state indicating that adjacent LEDs among the target LEDs are in an imaging state without dark bands separating them; after the camera parameters are adjusted, controlling the camera to take a picture of the LED display screen to obtain an image of the LEDs corresponding to the target LEDs; and obtaining evaluation information and / or calibration information of the LED display screen based on the image of the LEDs, wherein the evaluation information is used to evaluate the display quality of the LED display screen, and the calibration information is used to correct the brightness and / or chromaticity of the LED display screen.

[0008] In a second aspect, a system for evaluating / calibrating an LED display screen is provided, comprising: a camera for capturing images of the LED display screen; and an evaluation / calibration device for processing the images captured by the camera to perform the method as described in the first aspect.

[0009] Thirdly, a method for evaluating / calibrating an LED display screen is provided, comprising: acquiring an image of LED dots with all target LED dots illuminated, wherein the target LED dots are one or more of red, green, and blue LED dots within part or all of the display area of ​​the LED display screen, the image of the target LED dots in the LED dot image is in a connected state, the connected state being used to indicate that adjacent LED dots in the target LED dots are in an image without dark bands separating them; and acquiring evaluation information and / or calibration information of the LED display screen based on the LED dot image, wherein the evaluation information is used to evaluate the display quality of the LED display screen, and the calibration information is used to correct the brightness and / or chromaticity of the LED display screen.

[0010] Fourthly, an apparatus for evaluating / calibrating an LED display screen is provided, including a module for performing the method as described in the third aspect.

[0011] Fifthly, an apparatus for evaluating / calibrating an LED display screen is provided, comprising: a memory for storing a program; and a processor for executing the program stored in the memory to perform the method as described in the third aspect.

[0012] A sixth aspect provides a computer-readable storage medium having a program stored thereon for performing the method as described in the third aspect.

[0013] A seventh aspect provides a computer program product, including a program for performing the method as described in the third aspect.

[0014] Eighthly, a display screen control device is provided, including a memory for storing correction coefficients, wherein the correction coefficients are obtained based on target information, and the target information is obtained based on the method described in the third aspect; and a processor for calling the correction coefficients stored in the memory to correct the display screen. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of a system for evaluating / calibrating LED displays provided in an embodiment of this application.

[0016] Figure 2 This is an example image of a light spot.

[0017] Figure 3A This is an example diagram of a light spot pattern provided by related technologies.

[0018] Figure 3B This is an example diagram of the light dot pattern provided in the embodiments of this application.

[0019] Figure 4A It is the waveform diagram of the light spot corresponding to the light spot image provided by the relevant technology.

[0020] Figure 4B This is a waveform diagram of the light spot corresponding to the light spot image provided in the embodiments of this application.

[0021] Figure 5 This is a flowchart illustrating a method for evaluating / calibrating an LED display screen according to an embodiment of this application.

[0022] Figure 6 yes Figure 5 A flowchart illustrating one possible implementation of step S540 in the above steps.

[0023] Figures 7A-7E This is an example diagram of the calibration image provided in the embodiments of this application.

[0024] Figure 8 yes Figure 5 A flowchart illustrating another possible implementation of step S540 in the above steps.

[0025] Figure 9 yes Figure 8 The diagram shows an example of how the process is implemented.

[0026] Figure 10 yes Figure 8 A flowchart illustrating one possible implementation of step S840 in the above steps.

[0027] Figure 11A It is a schematic diagram of the outline of a distorted light spot image captured by a camera.

[0028] Figure 11B Yes Figure 11A The image showing the correction result after correction.

[0029] Figure 12 This is an example diagram of the camera image preview interface provided in the embodiments of this application.

[0030] Figure 13 This is a flowchart illustrating the process of evaluating the brightness uniformity of an LED display screen according to an embodiment of this application.

[0031] Figure 14 This is a flowchart illustrating the brightness correction process for an LED display screen provided in an embodiment of this application.

[0032] Figure 15 This is a flowchart illustrating a method for evaluating / calibrating an LED display screen, provided in another embodiment of this application.

[0033] Figure 16 This is a schematic diagram of an apparatus for evaluating / calibrating an LED display screen, provided as an embodiment of this application.

[0034] Figure 17 This is a schematic diagram of a device for evaluating / calibrating an LED display screen, provided in another embodiment of this application. Detailed Implementation

[0035] The embodiments of this application are intended for evaluating and / or calibrating LED displays. The LED display can be a conventional LED display, a microLED display, a miniLED display, or a future new type of LED display. Furthermore, in some embodiments, the LED display can be packaged using one of the following methods: for example, SMD, COB, COG, or a future novel packaging method.

[0036] An LED display screen can contain pixels, and each pixel can include one or more light points (or pixel lamps). For example, one pixel of an LED display screen can include three light points: red, green, and blue; or, one pixel of an LED display screen can include four light points: red, green, green, and blue. The evaluation / calibration of an LED display screen can sometimes be understood as the evaluation / calibration of the light points within the LED display screen (such as the evaluation / calibration of the brightness, color, etc. of the light points).

[0037] This application does not specifically limit the size of the LED display screen. For example, the LED display screen can be large in size, such as an LED display screen used in shopping malls or concerts. The LED display screen can be composed of many splicing units. These splicing units are sometimes called light boxes (such as LED light boxes). For LED display screens with light boxes as the basic unit, the LED display screen mentioned in this application can refer to an LED display screen corresponding to a single light box, or it can refer to an LED display screen composed of multiple light boxes spliced ​​together. The LED display screen mentioned in this application can also be a smaller-sized display screen, such as a light box or a light panel. With the future development of displays, smaller-sized LED display screens are likely to contain a larger number of pixels, and the methods provided in this application will also be applicable.

[0038] The term "evaluation" mentioned in the embodiments of this application can be understood as assessment or detection. The embodiments of this application do not specifically limit the content of "evaluation." For example, it can evaluate the uniformity of an LED display screen. Or, it can evaluate whether the LED display screen has other types of display defects. Furthermore, it can evaluate the display condition of an LED display screen, such as measuring color shift in the target display area.

[0039] The term "calibration" mentioned in this application can refer to correcting one or more of the brightness and / or chromaticity of an LED display screen. The calibration method can be to adjust relevant parameters of the LED display screen to improve its display quality or effect. For example, the luminous current of the LED display screen's LED points can be adjusted to maintain uniform brightness or chromaticity of the LED points.

[0040] To facilitate understanding of this application, it will be described in more detail below based on exemplary embodiments and in conjunction with the accompanying drawings. The same or similar reference numerals are used in the drawings to denote the same or similar modules. It should be understood that the drawings are merely illustrative, and the scope of protection of this application is not limited thereto.

[0041] Figure 1 This is a schematic diagram of the structure of a system for evaluating / calibrating LED displays provided in an embodiment of this application. Figure 1 The system 10 shown can be used to evaluate and / or calibrate the LED display screen 20. Figure 1 In this embodiment, system 10 does not include LED display screen 20. Of course, in other embodiments, LED display screen 20 may also be part of system 10.

[0042] like Figure 1As shown, the system 10 may include a camera 12 (or optical acquisition device). The camera 12 can be used to capture images of the LED display screen 20. The type of camera 12 can be selected according to actual needs, such as based on one or more factors including the size of the LED display screen and the accuracy requirements for evaluation / calibration. For example, the camera 12 can be a high-definition video camera, an optical camera, or an industrial camera.

[0043] To evaluate and / or calibrate the LED display screen 20, camera 12 can be used to capture images of the LED dots on the LED display screen 20. Image processing of these images can then be performed to obtain evaluation and / or calibration information for the LED display screen 20. The LED dot images mentioned here refer to images formed when target LED dots in the LED display screen are illuminated. "Target LED dots" can be understood as LED dots corresponding to one or more colors within part or all of the display area of ​​the LED display screen, such as one or more combinations of red, blue, and green LED dots. Figure 2 Let's take an example to illustrate. See [link / reference] Figure 2 The LED display screen 22 includes multiple pixels 24, and each pixel 24 includes three light points: red, green, and blue. Figure 2 The red light spot 241, the green light spot 242, and the blue light spot 243 are shown in the image. Figure 2 All red light points 241 in the image are lit. At this time, the image captured by the camera is the image of the light point corresponding to the red light point. Therefore, in this example, the red light point is the target light point mentioned earlier. For simplicity, some embodiments below will simply refer to "target light point" as "light point," and the two can be used interchangeably unless there is a conflict.

[0044] See again Figure 1 In addition to camera 12, system 10 may also include evaluation / calibration device 14. Evaluation / calibration device 14 can be used to process the light spot images captured by camera 12 to obtain evaluation information and / or calibration information of LED display screen 20.

[0045] The evaluation / calibration device 14 can be implemented in various ways. For example, the evaluation / calibration device 14 can be a computer (such as a desktop or laptop computer) or a mobile terminal (such as a mobile phone or tablet computer). The evaluation / calibration device 14 can be equipped with a software system 142 to perform the function of extracting evaluation information and / or calibration information from the lamp point image.

[0046] In some embodiments, the evaluation / calibration device 14 can also perform some or all of the control functions related to the system 10. For example, the evaluation / calibration device 14 can be used to control the LED display screen 20 (this control can be implemented via wired or wireless means). As a specific example, the evaluation / calibration device 14 can send control commands to the LED display screen 20 to control some of the LEDs in the LED display screen 20 to be lit and others to be in a non-lit state (such as a non-emitting state), thereby forming a LED image. The control function of the LED display screen 20 can be integrated into the software system 142 installed on the evaluation / calibration device 14.

[0047] The evaluation / calibration device 14 can also be used to control the camera 12 (this control can be achieved via wired or wireless means). For example, the evaluation / calibration device 14 can send parameter adjustment commands to the camera 12 to adjust the camera parameters of the camera 12. As another example, the evaluation / calibration device 14 can send shooting commands to the camera 12 to control the camera 12 to take pictures of the LED display screen 20. The control functions of the camera 12 can be integrated into the software system 142 installed on the evaluation / calibration device 14.

[0048] As mentioned earlier, the evaluation / calibration device 14 can process the light spot images captured by the camera 12 to obtain evaluation information and / or calibration information of the LED display screen.

[0049] The evaluation information can be used to evaluate the display quality of an LED display screen (or a target LED dot in the LED display screen). In some embodiments, the evaluation information of the LED display screen can be used to indicate the display status, display quality, or display effect of the LED display screen, or to evaluate whether there are display defects in the target display area. As an example, the evaluation information of the LED display screen can be used to indicate whether the brightness and / or chromaticity of the LED display screen is uniform (the brightness and / or chromaticity mentioned here can refer to the brightness and / or chromaticity at one or more gray levels). The evaluation information of the LED display screen can be calculated based on optical information (such as one or more of brightness information, chromaticity information, and luminous flux information) extracted from the dot image. For example, the brightness information of the LED display screen at a certain gray level can be calculated based on the dot image, and then the brightness uniformity of the LED display screen can be determined based on the calculated brightness information. To support the evaluation of the display quality of the LED display screen, an evaluation module 1421 (such as a uniformity evaluation module) can be installed in the software system 142 of the evaluation / calibration device 14. If you want to obtain evaluation information on the display quality of the LED display screen, simply input the image of the LED points captured by the camera into the evaluation module 1421.

[0050] The calibration information for the LED display screen can be used to correct the brightness and / or chromaticity of the LED display screen. The calibration information can be calculated based on optical information (such as brightness information, chromaticity information, luminous flux information, or one or more) extracted from the lamp image. For example, the brightness information of the LED display screen at a certain grayscale can be calculated based on the lamp image, and then the calibration information of the LED display screen can be determined based on the calculated brightness information. To support the calibration of the LED display screen, a calibration module 1422 can be installed in the software system 142 of the evaluation / calibration device 14. To obtain the calibration information of the LED display screen, the lamp image captured by the camera can be input into the calibration module 1422.

[0051] With the development of technology, the number of LED lights in LED displays is constantly increasing. Due to the limited pixels of cameras, it is difficult for cameras to capture all the lights on a large screen at once. Therefore, many related technologies control the LED display to light up at intervals, thereby capturing the LED light images at intervals (this solution will be referred to as the interval solution below, and the non-interval solution is the opposite of the interval solution).

[0052] However, with the continuous reduction in the spacing between LED dots in LED displays, especially with the emergence of miniLED and microLED, the coupling phenomenon between the dots has become increasingly obvious. This results in significant differences in the mura morphology of the dots under spaced-out and non-spaced-out lighting conditions (mura can be understood as various traces caused by uneven display on an LED screen). In this situation, the evaluation / calibration results of the spaced-out solution for LED displays are often inaccurate, and the non-spaced-out solution should be used instead.

[0053] The evaluation / calibration efficiency of non-spacing solutions provided by related technologies is very low, which is due to the low pixel utilization of the camera. Taking the calibration process of a common 2k×1k LED display as an example, related technologies often need to divide the LED display screen into many areas and then calibrate each area one by one, which is a very time-consuming process.

[0054] To facilitate understanding, the above problems and their underlying causes will be analyzed below.

[0055] Before using a camera to photograph an LED display screen, the relevant technology adjusts the camera parameters to ensure that the images of the LED dots are clear and that the images of the dots are separated by obvious dark bands to avoid crosstalk between them. Figure 3A (It should be understood that,) Figure 3A (The dashed box in the image is a marker line added for illustrative purposes and is not part of the lamp image.) An example of a lamp image used in related technologies is given. Figure 3A Reference numeral 32 in the attached figure indicates the center position of the light spot. From Figure 3A As can be seen, the light spots are separated by a wide dark band 34. Due to the presence of the dark band 34, the imaging of adjacent light spots does not interfere with each other, thus allowing for accurate determination of the optical information corresponding to each light spot. Figure 3A The reference numeral 36 in the attached figure shows the number of pixels corresponding to a single light point. It can be seen that imaging a single light point requires a relatively large number of pixels, typically 7×7 pixels. Even with camera parameter adjustments to minimize the width of the dark band 34, in the most extreme cases, imaging a single light point still requires at least 5×5 pixels.

[0056] After obtaining the pixels corresponding to each light point, the optical information (such as luminous flux information, brightness information, chromaticity information, etc.) of each light point can be calculated. In the actual calculation, since pixels in the dark band do not contain effective optical information, these pixels are essentially discarded. In other words, the pixels in the dark band 34 of the camera are wasted, resulting in low pixel utilization of the camera.

[0057] Therefore, how to provide an efficient and accurate non-interval point solution is an urgent problem to be solved. In order to solve the above problems, the inventors conducted a systematic analysis, research and testing of related technologies, and proposed a solution based on this, which is discussed in detail below.

[0058] The reason why related technologies require dark bands between pixels in the LED image is to ensure that the optical information of each pixel accurately measures its own luminescence without interference from adjacent pixels. This traditional view seems reasonable, but it overlooks a crucial fact: as LED display resolution increases and the spacing between LED pixels decreases, the light emitted by adjacent pixels in actual use will inevitably interfere with each other. The display defects observed by users are not those that occur when pixels do not interfere with each other, but rather those that occur when they interfere. Therefore, a more reasonable approach is that LED display evaluation / calibration does not need to be based on ensuring no interference between pixels. In other words, if the absence of display defects can be guaranteed even when pixels interfere with each other, users will not perceive any defects. Because the traditional view fails to fully recognize this, it requires dark bands to separate the pixels in the image. In reality, the mutual interference and influence between pixel images better reflects the actual usage of LED displays, making dark bands unnecessary. The embodiments of this application are based on the above findings and analyses. The above findings and analyses are not prior art, but should be regarded as part of the contribution of this application to the prior art.

[0059] Since setting dark bands between LED spot images is unnecessary, eliminating the requirement for dark bands between LED spot images allows for the representation of a single LED spot with fewer pixels, thus avoiding the pixel waste problem mentioned earlier and improving pixel utilization. Based on this, this application first proposes an LED spot image different from related technologies, based on which evaluation / calibration information of LED displays can be extracted more efficiently. The LED spot image proposed in this application embodiment will be described in detail below.

[0060] The light spot image proposed in this application embodiment is an image captured when all light spots of a certain color in part or all of the display area of ​​an LED display screen are lit (all light spots of a certain color being lit means that this application embodiment adopts a non-interlaced light spot scheme). For ease of description, some embodiments below refer to this certain color light spot as the target light spot. The target light spot can be one or more combinations of red, blue, or green light spots. Further, the main difference from traditional light spot images is that this application embodiment requires that the images of the light spots in the light spot pattern be in a connected state. The so-called "images of the light spots being in a connected state" means that there are no obvious dark bands between adjacent light spots (i.e., there are no areas with almost zero luminous flux). From the perspective of human eye observation, although the approximate position of the light spot (or the center of the light spot) can be identified from the light spot image, there are no obvious boundaries between adjacent light spots, giving the overall image a relatively blurry feeling.

[0061] Figure 3B An example image of the light spot is given. Figure 3B Reference numeral 32' in the attached diagram indicates the center position of the light spot. From Figure 3B The center position of the light spot can be roughly identified at 32' (i.e.) Figure 3B (The darkest part of the color). Furthermore, from... Figure 3B It can also be seen that the signal strength between adjacent lights exhibits a process of decreasing strength and then increasing again (signal strength at...). Figure 3B (It is represented by the depth of color), but there are no obvious dark bands between the light spots.

[0062] Figure 3B The reference numeral 36' in the attached diagram indicates the pixel corresponding to a light point. By comparison... Figure 3A and Figure 3B It can be seen that, Figure 3B In this case, the number of pixels corresponding to a single light point is reduced. For example, based on the light point image provided in the embodiments of this application, the number of pixels corresponding to a single light point can be reduced to 2.8 × 2.8 pixels, or even lower. Furthermore, compared to... Figure 3A and Figure 3B It can also be seen that, when using the same number of pixels, Figure 3B It can include imaging of more light points. Taking an LED display screen with a resolution of 2k×1k as an example, if the solution provided in the embodiments of this application is adopted, even if a non-spacing solution is used, the evaluation and / or calibration of the entire LED display screen can be completed in one go.

[0063] The imaging of adjacent LED points is in a state of overlap, which may include adjacent LED point imaging being in a state of adjacency and / or overlapping. If the imaging of adjacent LED points is in a state of overlap, the degree of overlap of the imaging of adjacent LED points in the LED point image can be determined based on one or more of the following factors: the evaluation and / or calibration accuracy of the LED display, the evaluation and / or calibration efficiency of the LED display, and the impact of the degree of overlap of the LED point imaging on the accuracy of the extracted evaluation / calibration information. As an example, the degree of overlap of the imaging of adjacent LED points in the LED point image can be between 10% and 80%. For example, the degree of overlap of the imaging of adjacent LED points in the LED point image can be between 10% and 50%, or between 20% and 30%.

[0064] In a lamp image, the position of the lamp is related to its DN value (DN value can be used to characterize the magnitude of a digital signal value), brightness value, or grayscale value. Based on this relationship, a waveform diagram of the lamp can be plotted. The waveform diagram of the lamp can, for example, be used to characterize the spatial light distribution curve of the lamp. As an example, the horizontal axis of the waveform diagram can be used to characterize the position of the lamp, and the vertical axis can be used to characterize the DN value, brightness value, or grayscale value of the lamp. From the perspective of the waveform diagram of the lamp, the imaging of adjacent lamps being in a state of overlap can include: in this waveform diagram, the waveform curves of adjacent lamps are connected end-to-end or overlap each other.

[0065] Figure 4 is used as an example for explanation. In Figure 4, the horizontal axis x represents the position of the light point, the vertical axis y represents the DN value, brightness value or grayscale value of the light point, and the attached label 42 indicates the waveform of a light point. Figure 4A This shows the waveform diagram of the light spot corresponding to the light spot image provided by related technologies. From... Figure 4A As can be seen, the waveform diagram includes 4 light points. The waveforms 42 of the light points are discontinuous and do not overlap. The interval between them can be understood as the "dark band" mentioned earlier. Figure 4B The diagram shown is a waveform diagram of the light spot corresponding to the light spot image provided in the embodiment of this application. From Figure 4B It can be seen that the waveforms 42 of the lamp points have overlapping parts 46, and the overall waveforms are in a state of adhesion.

[0066] The overlapping of images between light points in a light point image not only causes changes in the light point waveform but also produces similar changes in the image of the camera's image sensor (such as CMOS or CCD). Specifically, a cross-sectional view of the image sensor can be drawn from the imaging angle of the camera's image sensor. The horizontal axis of the image sensor's cross-sectional view can represent the position of row (or column) pixels in the light point image, and the vertical axis can represent the pixel's DN value, brightness value, or grayscale value. From the perspective of this image cross-sectional view, the overlapping of images between adjacent light points can include: in this image cross-sectional view, the curves corresponding to adjacent light points are connected end-to-end or overlap. The curves of the image cross-sectional views provided in related technologies and embodiments of this application are respectively... Figure 4A and Figure 4B Similarly, details will not be elaborated here.

[0067] In some embodiments, the difference between the maximum and minimum brightness in the light spot image is between 10% and 50%. For example, the difference between the maximum and minimum brightness in the light spot image is between 20% and 30%. It should be understood that the difference between the maximum and minimum brightness in the light spot image can be determined based on the ratio of the minimum brightness to the maximum brightness.

[0068] In some embodiments, the difference between the maximum and minimum gray levels in the light spot image is between 10% and 50%. For example, the difference between the maximum and minimum gray levels in the light spot image is between 20% and 30%. It should be understood that the difference between the maximum and minimum gray levels in the light spot image can be determined based on the ratio of the minimum gray level to the maximum gray level.

[0069] In some embodiments, the difference between the maximum and minimum DN values ​​in the lamp image is between 10% and 50%. For example, the difference between the maximum and minimum DN values ​​in the lamp image is between 20% and 30%. It should be understood that the difference between the maximum and minimum DN values ​​in the lamp image can be determined based on the ratio of the minimum DN value to the maximum DN value.

[0070] It should be understood that, generally speaking, the LED dots in an LED display screen are arranged roughly evenly. Therefore, if the images of a pair of adjacent LED dots in an LED display screen are in a "stuck" state in the dot image, the images of other adjacent LED dots in the LED display screen will also be basically in a "stuck" state. However, the embodiments of this application do not exclude the existence of special cases, namely, the situation where the images of some adjacent LED dots are in a "stuck" state and the images of some adjacent LED dots are not in a "stuck" state. For example, if there are dead pixels in the LED display screen, the LED dots at the dead pixel location may not be stuck together with their adjacent LED dots. Similarly, if the LED display screen is composed of multiple splicing units, and the gaps between the splicing units are large, the adjacent LED dots at the gaps may not be stuck together. Furthermore, since camera shooting involves a certain degree of deformation (or distortion), and the degree of deformation of LED dot areas at different positions / angles in the dot image may be different, it is not ruled out that the images of adjacent LED dots in a certain dot area (such as a dot area with large deformation) may be in a non-stuck state.

[0071] Based on the aforementioned LED dot image, this application provides a method for evaluating / calibrating an LED display screen. This method can efficiently obtain evaluation and / or calibration information for the LED display screen based on the LED dot image. The following describes the method in conjunction with... Figure 5 This section provides a detailed description of the method. In some embodiments, Figure 5 The method can be derived from Figure 1 The system shown is executed or performed by the evaluation / calibration device within the system. For example, the evaluation / calibration personnel can control the LED display and / or camera through the evaluation / calibration device to complete the task. Figure 5 The steps involved are related to the control of the LED display and / or camera. Furthermore, the software system in the evaluation / calibration device can be used to process the light spot images captured by the camera to obtain evaluation / calibration information for the LED display. Of course, Figure 5 The method can also be implemented in other ways. For example, in some embodiments, Figure 5 Some steps in the method can be performed manually by the personnel responsible for evaluation and / or calibration. For example, one or more steps in the following description, such as the LED display lighting step (step S510), the camera parameter adjustment step (step S520), and the camera shooting step (step S530), can be performed manually.

[0072] See Figure 5 In step S510, all target LEDs within part or all of the LED display area are illuminated to perform non-interval image acquisition of the target LED. The target LED can be a specific color. For example, the target LED can be one or more combinations of red, blue, or green LEDs.

[0073] In step S520, the camera parameters are adjusted so that the images of the target lights are in a blurred state. The camera's image preview interface can, for example, be... Figure 1 The software system 142 shown is provided. Camera parameters may include one or more of the following parameters: camera aperture, exposure time, focal length (zoom lens), macro focus, etc. The image of the target light points being in a "cohesive" state can also be understood as an imaging state in which adjacent light points within the target light points are not separated by dark bands. A detailed explanation of the cohesive state can be found above.

[0074] It should be understood that there are several ways to adjust the imaging of the target light points to a connected state. For example, the proportion of light points in the light point image can be adjusted, that is, the number of pixels corresponding to each light point in the light point image can be adjusted, so that at least some of the light points in the target display area are in a connected state.

[0075] Furthermore, in some embodiments, one or more of the camera image sharpness and light spot peak values ​​can be adjusted to meet certain requirements, thereby facilitating subsequent information extraction. These indicators can be set according to actual needs or experience, and will not be elaborated upon in this application.

[0076] It should be understood that the order of steps S510 and S520 is not specifically limited in the embodiments of this application. For example, the target light point can be controlled to be in an illuminated state first, and then the camera parameters can be adjusted so that the image of the target light point is in a blurred state. Alternatively, the camera parameters can be adjusted based on experience or a test image first, and then the target light point can be controlled to be in an illuminated state. In this example, since the camera parameters have been pre-adjusted, when the target light point is in an illuminated state, the image of the target light point is naturally in a blurred state. Of course, in some embodiments, if the camera parameters themselves meet the requirements, step S520 can be omitted.

[0077] It should be understood that the target display area's display pattern during camera parameter adjustment should be consistent with the pattern used when acquiring optical information. For example, during calibration, if the target display area uses a point-by-point display pattern, it should also use a point-by-point display pattern when adjusting camera parameters. Similarly, if the target display area uses a 2x2 display pattern during calibration, it should also use a 2x2 display pattern when adjusting camera parameters.

[0078] In one preferred implementation, different colored light points correspond to different camera parameters. Specifically, the main difference lies in the exposure time. For example, at the same grayscale, green is relatively brighter, and blue is relatively darker; therefore, different colors require different camera exposure times. For instance, all green light points in the target display area can be illuminated first, the camera can capture an image of the target display area, and based on the captured image, the user and / or PC can adjust the camera parameters to obtain the camera parameters when the target display area displays green. The same method can be used to obtain the camera adjustment parameters when the target display area displays red, and the camera adjustment parameters when it displays blue. Alternatively, the camera parameters for red and blue can be calculated based on the relationship between the camera parameters for red, green, and blue, according to the camera parameters corresponding to green. Or, a combination of both methods can be used for adjustment. In another optional implementation, the camera parameters that need to be adjusted mainly include: macro focus, aperture, and exposure time.

[0079] There are several ways to determine whether the camera parameter adjustment meets the requirements (i.e., whether the adjusted camera parameters make the image of the target light point in a sticky state). Here are a few examples.

[0080] For example, a preset range can be set for the overlap of the target lights (hereinafter referred to as the first preset range). Then, the camera parameters can be adjusted so that the overlap of the target lights captured by the camera falls within this first preset range. Once the overlap of the target lights captured by the camera falls within this first preset range, the adjustment of the camera parameters can be considered to have met the requirements.

[0081] For example, a preset range of grayscale values ​​can be set for the target light point (hereinafter referred to as the second preset range, which can be defined by the maximum and minimum grayscale values ​​of the target light point). Then, the camera parameters can be adjusted so that the grayscale values ​​of the target light point captured by the camera fall within this second preset range. Once the grayscale values ​​of the target light point captured by the camera fall within this second preset range, the adjustment of the camera parameters can be considered to have met the requirements.

[0082] For example, a preset range can be set for the brightness of the target light point (hereinafter referred to as the third preset range, which can be defined by the maximum and minimum brightness of the target light point). Then, the camera parameters can be adjusted so that the brightness of the target light point captured by the camera falls within this third preset range. Once the grayscale of the target light point captured by the camera falls within this third preset range, the adjustment of the camera parameters can be considered to have met the requirements.

[0083] The first, second, and third preset ranges mentioned above can be empirical values ​​or measured values ​​obtained through experiments based on the actual situation of the camera. This application does not specifically limit them. For example, the first preset range can be 10%-50%; the second preset range can be 10-30%; and the third preset range can be 10-30%.

[0084] In step S530, after the camera parameters are adjusted, the camera is controlled to capture an image of the LED display screen to obtain an image of the target light point. This light point image can be a solid color image. For example, the light point image may include one or more of the following: a green light image formed by green light points lit up in the LED display screen; a red light image formed by red light points lit up in the LED display screen; a blue light image formed by blue light points lit up in the LED display screen; and a mixed color image formed by light points of at least two colors lit up in the LED display screen. The meaning of the light point image can be found above.

[0085] In step S540, evaluation information and / or calibration information of the LED display screen are obtained based on the lamp point image. The evaluation information of the LED display screen can be used to evaluate the display quality of the LED display screen (such as the target lamp point in the LED display screen). The calibration information of the LED display screen can be used to correct the brightness and / or color of the LED display screen (such as the target lamp point in the LED display screen). For a detailed introduction to the evaluation information and / or calibration information, please refer to the preceding text.

[0086] As described above, this application adopts a non-interlaced pixel scheme, which can better reflect the mura morphology of the LED display screen in actual use. Furthermore, this application adjusts the camera parameters in the camera's image preview interface to make the target light points appear in a contiguous state. In this light point image, the contiguous light point imaging area does not have obvious dark bands. In other words, the pixel value of each pixel in this light point imaging area contains useful optical information. In the subsequent calculation of LED display screen evaluation / correction information, the pixel information of each pixel will be fully utilized and will not be discarded like pixels in dark bands, thereby improving the camera's pixel utilization rate. In addition, because the light point imaging is in a contiguous state, the light point image can use fewer pixels to represent one light point, allowing the camera to capture a larger display area at once, improving the evaluation and / or correction efficiency of the LED display screen.

[0087] As mentioned earlier, an LED display screen can include multiple splicing units. For example, such an LED display screen can be composed of multiple LED light boxes spliced ​​together. Due to limitations in machining precision and assembly precision, the distance between the LED dots at the edges of adjacent splicing units may be greater or less than the distance between LED dots in other areas, thus forming gaps (or seams). The luminous density of the LED dots at the gaps may differ from that of the LED dots in other areas. Therefore, during the display process, a bright or dark line may sometimes appear at the gaps, known as a splicing bright / dark line, affecting the display effect. Therefore, related technologies require not only individual calibration of the LED dots but also calibration of the gaps between the splicing units. Performing these two types of calibration separately is inefficient.

[0088] In the lamp point image provided in this application embodiment, the imaging of adjacent lamp points is in a state of adhesion. Therefore, due to the influence of the gap, the trend of change of optical information (or light color information) between adjacent lamp points within the splicing unit and adjacent lamp points on both sides of the gap differs. In other words, compared with the lamp point image based on dark bands used in related technologies, the lamp point image used in this application embodiment includes not only lamp point information but also gap information between splicing units. Therefore, this lamp point image can reflect not only the display quality of the lamp points but also the influence of the gap on the display quality.

[0089] Therefore, when the LED display screen is calibrated using the lamp point image provided in this application embodiment, the calibration information extracted from the lamp point image can simultaneously correct the gaps. For example, the calibration information of the LED display screen includes calibration parameters corresponding to the target lamp point, and after calibration by these parameters, the brightness of the target lamp point is uniform throughout the entire LED display screen. As mentioned above, the lamp point image actually contains gap information. Since the calibration parameters corresponding to the target lamp point can make the target lamp point display uniformly, it means that the calibration parameters corresponding to the target lamp point not only complete the calibration of the target lamp point itself, but also complete the calibration of the gap. In other words, the calibration parameters corresponding to the target lamp point implicitly contain the calibration parameters for the gap.

[0090] Therefore, the lamp point image provided in this application embodiment can not only improve the correction efficiency of the LED display screen from the perspective of improving camera pixel utilization, but also combine lamp point correction and gap correction into one, thereby further improving the correction efficiency of the LED display screen.

[0091] See again Figure 5 Step S540 describes obtaining evaluation information and / or calibration information of the LED display screen based on the lamp dot image. There are various ways to implement step S540; the following describes in detail, with reference to specific embodiments, how the evaluation information and / or calibration information is obtained.

[0092] Before using LED spot images to obtain evaluation and / or calibration information for LED displays, it is generally necessary to first locate the target LED spot, that is, determine the position of the target LED spot in the LED spot image, or in other words, determine the correspondence between the target LED spot and the pixels in the LED spot image. Then, based on the pixels corresponding to each target LED spot, the optical information corresponding to each target LED spot can be determined, thereby determining the evaluation and / or calibration information for the LED display.

[0093] There are several methods for locating light points. For example, a template of pixels corresponding to each light point can be pre-defined. Then, based on this template, the pixels corresponding to each light point can be extracted from the light point image through template matching. Next, the optical information corresponding to each light point can be obtained based on the pixels corresponding to each light point. Alternatively, an edge detection algorithm can be used to calculate the pixels corresponding to each light point in the light point image, and then the optical information corresponding to each light point can be obtained based on the pixels corresponding to each light point.

[0094] In addition to the above methods, this application also proposes a simpler and more efficient lamp positioning method, namely a lamp positioning method based on the lamp arrangement information of the LED display screen.

[0095] "LED display lamp arrangement information" can be used to indicate the arrangement and / or position of indicator lights within the LED display. For example, the LED display lamp arrangement information can indicate the number of rows / columns of the LED display, thus indicating the arrangement or position of the lights within the LED display. Since the number and position of the LED display are known, "LED display lamp arrangement information" is actually a kind of prior information that can be obtained in advance.

[0096] In some embodiments, the LED display's lamp arrangement information can refer to the LED display's resolution information. For example, assuming the LED display's resolution is 1920×1080, and the lamp image is the image formed after all the red LEDs in the LED display are lit, the LED display's resolution information can be directly used as the lamp arrangement information. This resolution information can indicate that the LED display has 1920 rows of LEDs arranged in the row direction and 1080 columns of LEDs arranged in the column direction. Since the LEDs are generally evenly distributed, the position of each LED can be determined based on this resolution information through simple calculations. For example, the lamp image can be evenly divided into 1920×1080 pixel regions according to the resolution, and then each pixel region can represent the position of one LED.

[0097] Compared with methods such as template matching and edge detection, the lamp positioning method based on the lamp layout information of the LED display screen is simpler and more efficient.

[0098] The following text combines Figure 6 The process of extracting evaluation and / or calibration information of LED displays from LED image based on LED layout information is illustrated in more detail with examples.

[0099] See Figure 6 In step S610, the correspondence between the target light point and the pixels in the light point image is determined based on the light point arrangement information of the LED display screen.

[0100] For example, the light dot layout information indicates that there are 2k×1k light dots arranged in the LED display screen. Assuming that the light dot image contains 6k×3k pixels, then one light dot in the LED display screen corresponds to 3×3 pixels at the corresponding position in the light dot image.

[0101] For example, the LED dot layout information can be used to sample the LED dot image, ensuring a one-to-one correspondence between pixels in the sampled image and each LED dot. This allows the optical information of each pixel in the sampled image to be directly used as the optical information of the corresponding LED dot. As a concrete example, if the LED dot layout information indicates that the LED display contains 2k × 1k LEDs, and the dot image contains 6k × 3k pixels, the dot image can be sampled to contain 2k × 1k pixels. After this sampling operation, one LED dot in the LED display corresponds to a pixel at a specific position in the dot image, simplifying the calculation of subsequent LED display evaluation / calibration information.

[0102] It should be understood that there are multiple sampling methods for the light spot image mentioned above. For example, the average sampling (such as mean downsampling) can be performed on adjacent pixels in the light spot image, or the adjacent pixels of the pixel at the sampling center position can be directly discarded. As an example, the average downsampling can be performed on each column of pixels in the light spot image in the column direction, so that the number of pixels in each column is sampled to the same resolution as the height direction of the LED display; then, the average downsampling can be performed on each row of pixels in the row direction, so as to obtain a light spot image with the same resolution as the LED display. As another example, the average downsampling can be performed on each row of pixels in the row direction, so that the number of pixels in each row is sampled to the same resolution as the width direction of the LED display; then, the average downsampling can be performed on each column of pixels in the column direction, so as to obtain a light spot image with the same resolution as the LED display. As yet another example, the average downsampling can be performed on both the row and column directions of the light spot image simultaneously until a light spot image with the same resolution as the LED display is obtained.

[0103] In step S620, the optical information corresponding to the target light point is determined based on the correspondence between the target light point and the pixels in the light point image. For example, the brightness information of the pixel corresponding to a certain light point in the light point image can be directly used as the brightness information of that light point. Similarly, the chromaticity information of the pixel corresponding to a certain light point in the light point image can be directly used as the chromaticity information of that light point. Furthermore, the luminous flux information of the pixel corresponding to a certain light point in the light point image can be directly used as the luminous flux information of that light point.

[0104] In step S630, evaluation information and / or calibration information of the LED display screen are obtained based on the optical information corresponding to the target light point. For example, the optical information corresponding to the target light point can be input to an evaluation module (such as a uniformity evaluation module), and the evaluation information output by the evaluation module can be used as the evaluation information of the LED display screen. Alternatively, the optical information corresponding to the target light point can be input to a calibration module, and the calibration information output by the calibration module can be used as the calibration information of the LED display screen.

[0105] Images of LED lights captured by a camera will exhibit a certain amount of distortion. This distortion is sometimes referred to as perspective distortion or perspective warping. The degree of distortion is related to factors such as the camera's focal length, shooting distance, and shooting angle. For example, the shorter the focal length and the closer the shooting distance, the greater the distortion may be. If the LED display screen is large, certain areas within it will also exhibit significant distortion in the LED light image. If the LED display screen can be divided into multiple zones, and the positional information of these zones in the LED light image can be accurately determined, then the optical information corresponding to each zone can be extracted separately. Compared to the overall distortion of the LED display screen, the distortion corresponding to each zone is relatively small, and extracting optical information based on zones improves the accuracy of information extraction.

[0106] To extract optical information based on partitions, it is necessary to know the positional information of each partition in the lamp point image. This application proposes a partition positioning method based on a calibration image (or positioning image) to quickly and accurately obtain this positional information.

[0107] Specifically, after camera parameter adjustment is complete, a calibration image can be taken using the camera. This calibration image can be used to divide the LED display screen into multiple zones (or in other words, the calibration image contains the positional information of multiple zones). Since the lamp point image and the calibration image are taken under the same camera parameters and on the same display area of ​​the LED display screen (i.e., the LED display screen itself), the distortion presented in the two images is the same. Therefore, based on the positional information of the multiple zones contained in the calibration image, the positions of these multiple zones in the lamp point image can be accurately located.

[0108] The number of partitions into which the LED display screen is divided and the size of each partition can be set according to the actual situation. For example, the multiple partitions can be set according to the following principle: after the camera captures the image within each partition, the deformation of that partition is within an acceptable range (or, the deformation of each partition is within a negligible range).

[0109] In a preferred embodiment, since the calibration image is used for positioning, but the positions of different colored light points are different, different calibration images corresponding to different colored light points can make the positioning more accurate. Therefore, in some embodiments, the aforementioned light point image may include a first light point image and a second light point image. The first light point image and the second light point image correspond to light points of different colors within the target display area. Accordingly, the calibration image may include a first calibration image corresponding to the first light point image and a second calibration image corresponding to the second light point image. The first calibration image and the second calibration image are different. The difference between the first calibration image and the second calibration image may be reflected in one or more of the following: the pattern colors in the first calibration image and the second calibration image are different; the position information of the partitions provided by the first calibration image and the second calibration image are slightly different (because the positions of the light points of different colors in the target display area are slightly different).

[0110] For example, the first light spot image can be a red light spot image, and the second light spot image can be a blue light spot image. The red light spot image is paired with a red calibration image; based on the red calibration image and the red light spot image, the optical information of the red light spot is obtained. Similarly, the blue light spot image is paired with a blue calibration image; based on the blue calibration image and the blue light spot image, the optical information of the blue light spot is obtained. Likewise, if it is necessary to obtain the optical information of light spots displaying a mixed color in the target display area, a mixed color calibration image can be used.

[0111] It should be understood that the order in which the LED display shows the calibration image and the pattern used to extract optical information is not limited in this application.

[0112] In some embodiments, the calibration image may include patterns corresponding to multiple zones within the LED display screen. By displaying multiple zones of the LED display screen, the calibration image allows for the location of these zones within the light dot image. The multiple patterns corresponding to each zone in the calibration image can be alternating light and dark (or black and white) patterns. Alternating light and dark patterns are beneficial for accurately identifying the boundaries of each zone. For example, with an LED display screen resolution of 1920*1080, a checkerboard pattern can be used. For instance, by displaying the green light dots of the target display area point by point to obtain a green light dot image, a green and black checkerboard pattern can be obtained, where each checkerboard cell can, for example, include 64*60 pixels.

[0113] Besides a checkerboard pattern, the calibration image can also be one or more combinations of the following: crosshairs, Aruco codes, special lines, light dots, and a grid. The special lines can be several vertical lines; for example, displaying three vertical lines on an LED display divides the display area into four zones. The Aruco codes are binary codes, which can be understood as a rectangular code composed of only two colors. The scattered dots are a pattern composed of multiple dots.

[0114] The following, with reference to Figure 7, provides several more specific examples of calibration images. It should be understood that the calibration images shown in Figure 7 are intended to illustrate the pattern type of calibration images and do not take into account the effects of camera perspective distortion.

[0115] Figure 7A This is an example of a calibration image provided in an embodiment of this application. For example... Figure 7A As shown, the calibration image includes multiple illuminated areas. Figure 7A (black areas in the image) and multiple non-lit areas ( Figure 7A (The white area in the middle).

[0116] Figure 7B This is another example of a calibration image provided in the embodiments of this application. For example... Figure 7B As shown, the calibration image includes multiple illuminated areas. Figure 7B (black areas in the image) and multiple non-lit areas ( Figure 7B (the white area in the middle), and the lit and unlit areas are in Figure 7B The middle is arranged alternately.

[0117] Figure 7C This is yet another example of a calibration image provided in the embodiments of this application. For example... Figure 7C As shown, the calibration image includes multiple discontinuous lit light points ( Figure 7C The black circular area in the middle), and multiple non-lit light points ( Figure 7C (The white circular area in the middle).

[0118] Figure 7D This is yet another example of a calibration image provided in the embodiments of this application. For example... Figure 7D As shown, the calibration image is a grid pattern. Each cell in the grid pattern marks a section of the LED display screen.

[0119] Figure 7E This is yet another example of a calibration image provided in the embodiments of this application. For example... Figure 7E As shown, the calibration image is a scatter pattern composed of multiple scattered points.

[0120] The meaning and types of calibration images have been explained in detail above. The following text describes the method of obtaining evaluation / calibration information of LED displays from lamp point images based on calibration images (which can be understood as...). Figure 5 The implementation method of step S540 in the example will be explained in detail with examples.

[0121] See Figure 8 In steps S810 to S820, after the camera parameters are adjusted, the LED display screen is controlled to display the calibration image, and the camera is controlled to capture the calibration image. A description of the camera parameter adjustment can be found in step S520 above.

[0122] In step S830, the lamp image is divided into multiple images corresponding one-to-one with multiple partitions based on the calibration image. For example, if the calibration image contains location information of multiple partitions, the lamp image can be divided into multiple images based on this location information, so that each image represents one partition.

[0123] In steps S840 to S850, optical information (or color information) corresponding to the multiple partitions is determined based on the multiple images; and evaluation information and / or calibration information of the LED display screen is obtained based on the optical information corresponding to the multiple partitions.

[0124] by Figure 9 For example, after the camera parameters are adjusted, the LED display screen can be controlled to display calibration image 92, which shows alternating bright and dark LED dots. In calibration image 92, black represents LED dots that are lit, and white represents LED dots that are not lit, with every four adjacent LED dots forming a partition. Then, the camera can be controlled to capture the calibration image 92 displayed on the LED display screen, thus obtaining calibration image 92'. Comparing calibration image 92 and calibration image 92', it can be seen that the LED dots that were originally evenly spaced in calibration image 92 have undergone a certain amount of deformation in calibration image 92'.

[0125] After capturing the calibration image 92, the LED display screen can be controlled to show the light spot image 94. Then, the camera can be controlled to capture the light spot image 94, thus obtaining the light spot image 94'. Comparing the light spot image 94 and the calibration image 94', it can be seen that the originally evenly spaced light spots in the light spot image 94 also undergo a certain amount of deformation in the light spot image 94', and the deformation of the light spot image 94' and the calibration image 92' is the same. Next, taking advantage of the fact that the two have the same deformation, the light spot image 94' can be divided into partitions in the same way as the calibration image, thus forming multiple images 96 corresponding to multiple partitions. Since the size of the partitions corresponding to images 96 is small, the deformation within images 96 is also relatively small and can be basically ignored. After obtaining multiple images 96, the optical information of each partition can be extracted based on these multiple images 96.

[0126] Therefore, this embodiment transforms the task of determining the optical information of an LED display screen based on lamp point images into multiple sub-tasks, where each sub-task determines the optical information corresponding to a partition of the LED display screen. Then, this embodiment can aggregate the optical information corresponding to each partition to obtain the evaluation / calibration information of the LED display screen. Since the deformation corresponding to each partition is relatively small, dividing the LED display screen into multiple partitions and extracting optical information on a partition-by-partition basis can reduce the impact of deformation caused by camera shooting on the accuracy of the obtained evaluation / calibration information.

[0127] There are multiple ways to implement step S840. For ease of description, the following example uses the first partition among multiple partitions (which can be any one of the multiple partitions, and the first partition corresponds to the first image among the multiple images divided in the lamp point image) to illustrate the implementation of step S840.

[0128] Before acquiring optical information from the first image, it is generally necessary to locate the light sources first, that is, to determine the position of the light sources within the first partition in the first image, or in other words, to determine the correspondence between the light sources within the first partition and the pixels in the first image. Then, based on the pixels corresponding to each light source, the optical information corresponding to each light source can be determined.

[0129] There are several ways to locate light points within a partition. For example, a template for the pixels corresponding to each light point can be pre-defined. Then, based on this template, the pixels corresponding to each light point can be extracted from the first image through template matching. Finally, the optical information corresponding to each light point can be obtained based on the pixels corresponding to each light point. Alternatively, an edge detection algorithm can be used to calculate the pixels corresponding to each light point in the first image, and then the optical information corresponding to each light point can be obtained based on the pixels corresponding to each light point.

[0130] In addition to the methods described above, this application also proposes a simple and efficient light point positioning method, namely, a light point positioning method based on the light point layout information of the first zone. The "light point layout information of the first zone" can be used to indicate the layout method and / or position of the indicator lights within the first zone. For example, the light point layout information of the first zone can indicate the number of rows / columns of the lights contained in the first zone, thereby indicating the layout method or position of the lights within the first zone. Since the first zone is known, the "light point layout information of the first zone" is actually a kind of prior information obtained in advance.

[0131] Taking a rectangular area as an example, the light distribution information of the first partition can refer to the resolution information of that partition. For instance, assuming the resolution of the first partition is 480×270, and the first image is formed after all the red lights in the first partition are lit, the resolution information of the first partition can be directly used as the light distribution information. This resolution information indicates that there are 480 rows of lights arranged in the row direction and 270 columns of lights arranged in the column direction of the first partition. Since the lights are generally evenly distributed, this resolution information is equivalent to indicating the specific position of each light in the first image. After simple calculation, the light location can be completed. Compared with methods such as template matching and edge detection, this light location method is simpler and more efficient.

[0132] The following text combines Figure 10 The process of extracting optical information from the first image based on the lamp layout information of the first partition (corresponding to...) Figure 8 The steps in step S840 will be illustrated in more detail with examples.

[0133] See Figure 10 In step S1010, the correspondence between the target light points in the first partition and the pixels in the first image is determined based on the light point layout information of the first partition.

[0134] For example, if the light distribution information of the first zone indicates that there are 640×360 light points arranged in the first zone, and the first image contains 1920×1080 pixels, then one light point in the first zone corresponds to 3×3 pixels at the corresponding position in the light point image.

[0135] For example, the first image can be sampled based on the lamp layout information of the first partition, so that the pixels in the sampled image correspond one-to-one with the lamps in the first partition. In this way, the optical information of each pixel in the sampled image can be directly used as the optical information of the lamp corresponding to that pixel in the first partition. As a specific example, if the lamp layout information of the first partition indicates that the first partition contains 640×360 lamps and the first image contains 1920×1080 pixels, then the first image can be sampled first, so that the first image contains 640×360 pixels. After this sampling operation, one lamp in the first partition corresponds to one pixel at the corresponding position in the first image. Based on this one-to-one correspondence, the subsequent calculation of optical information can be simplified.

[0136] In step S1020, the optical information corresponding to the target light point in the first partition is determined based on the correspondence between the target light point in the first partition and the pixels in the first image. For example, the brightness information of the pixel in the first image corresponding to a certain light point can be directly used as the brightness information corresponding to that light point. Similarly, the chromaticity information of the pixel in the first image corresponding to a certain light point can be directly used as the chromaticity information corresponding to that light point. Furthermore, the luminous flux information of the pixel in the first image corresponding to a certain light point can be directly used as the luminous flux information corresponding to that light point.

[0137] Figure 11A This is a schematic diagram showing the outline of the LED display screen's light points as captured by a camera. For example... Figure 11A As shown, since the camera is not directly facing the LED display screen, the image is somewhat distorted. Therefore, in some embodiments, the image of the LED point can be modified to make it a straight rectangle. Figure 11B What is shown is Figure 11A The image shown is obtained after transforming (e.g., perspective transformation) the light spot image. Using... Figure 11B Extracting subsequent evaluation / correction information can improve the accuracy of the extracted evaluation / correction information.

[0138] See again Figure 5 , Figure 5Step S520 describes the need to adjust camera parameters on the camera's image preview interface before capturing the image of the light points, so that the images of the target light points within the LED display screen are in a connected state. The camera parameter adjustment can be performed on the camera's image preview interface. This image preview interface can be generated by the evaluation / calibration device. For example, the software system in the evaluation / calibration device can present the camera's image preview interface to assist evaluation and / or calibration personnel in adjusting camera parameters. This camera image preview interface can display a preview image of the light points. If the light point images in the preview image are not in a connected state, the evaluation and / or calibration personnel can adjust the camera parameters on this image preview interface until the images between the light points are in a connected state.

[0139] For those unfamiliar with the technical solutions provided in the embodiments of this application, reducing the size of the preview image might make it appear "blurry." The evaluator and / or calibrator might mistakenly believe that such a small preview image already meets the requirement of "making the images of the lamp points in the lamp point image appear to be in a state of overlap." However, this is incorrect because excessive overlap between the lamp points will result in inaccurate extracted optical data.

[0140] To avoid the aforementioned problems, embodiments of this application control the image preview interface of the camera to display instruction information, which can be used to limit the size of the preview image of the light point image in the image preview interface. Alternatively, the instruction information can be used to specify the required size of the preview image of the light point image. There are various ways to implement this instruction information. For example, the instruction information can be text indicating the minimum size of the preview image, a bounding box limiting the minimum size of the preview image, or a combination of the above. As an example, see... Figure 12 The indication information may include a rectangular area 1230 displayed on the image preview interface 1220. This indication information can be used to indicate that the preview image needs to fill or substantially fill the rectangular area 1230 (substantially filling can be understood as the boundary of the preview image needing to reach or approach the boundary of the rectangular area 1230). Alternatively, the indication information can be used to indicate that the size displayed in the rectangular area 1230 is the minimum size of the preview image. Further, the indication information may also include text information 1240. This text information may, for example, be... Figure 12The text displayed reads, "Please ensure the preview image fills the area within this dashed box." Alternatively, in some embodiments, the text message may read, "Please ensure the boundaries of the preview image are outside the range of this dashed box." This text message can prompt evaluation and / or calibration personnel to control the size of the preview image within an appropriate range. When evaluation and / or calibration personnel find that the preview image does not meet the requirements of this instruction, they can adjust the distance between the camera and the LED display (or adjust the camera's focal length or macro focus) until the size of the light spot image meets the requirements.

[0141] The following is combined with Figure 13 and Figure 14 Here are a few specific examples. Figure 13 and Figure 14 The examples described can be derived from Figure 1 The system shown is executing. Note that... Figure 13 and Figure 14 The examples described are merely to help those skilled in the art understand the embodiments of this application, and are not intended to limit the embodiments of this application to the specific numerical values ​​or specific scenarios illustrated. Those skilled in the art will obviously be able to make various equivalent modifications or variations based on the given examples, and such modifications or variations also fall within the scope of the embodiments of this application.

[0142] Example 1: Evaluation of brightness uniformity of LED display screen

[0143] See Figure 13 In step S1310, the entire display area of ​​the LED screen is controlled to display red, green, and blue LED images respectively. That is, the LED screen is controlled to perform red, green, and blue pure color image display. The grayscale of the image display can be set according to customer requirements. When the LED screen displays an image of a certain color, that color LED is the target LED mentioned earlier.

[0144] In step S1320, the camera is controlled to acquire images of the LED display screen's light points and generate luminous flux information corresponding to the LED display screen's light points.

[0145] Specifically, before acquiring images of the LED lights on the display screen, the camera is adjusted so that the images of the lights appear to overlap. Then, the camera is used to acquire brightness information. Next, perspective distortion is used to correct the image shape of the lights, and the images are downsampled to match the resolution of the LED display screen. After downsampling, the luminous flux information for each light on the LED display screen can be calculated based on the one-to-one correspondence between the images and the lights themselves.

[0146] In step S1330, the brightness uniformity of the LED display screen is evaluated based on the luminous flux information corresponding to each lamp point. For example, after obtaining the luminous flux information corresponding to each lamp point of the LED display screen, the luminous flux information can be input into the uniformity evaluation module to evaluate the brightness uniformity of the LED display screen.

[0147] Example 2: Brightness calibration of LED display screen

[0148] See Figure 14 In step S1410, the entire display area of ​​the LED screen is controlled to display red, green, and blue LED images respectively. In other words, the LED screen can be controlled to display red, green, and blue pure colors separately. The grayscale of the display can be set according to customer requirements.

[0149] In step S1420, the camera is controlled to acquire images of the LED display lights and generate luminous flux information corresponding to the LED display lights.

[0150] Specifically, before acquiring images of the LED lights on the display screen, the camera is adjusted so that the images of the lights appear to overlap. Then, the camera is used to acquire brightness information. Next, perspective distortion is used to correct the image shape of the lights, and the images are downsampled to match the resolution of the LED display screen. After downsampling, the luminous flux information for each light on the LED display screen can be calculated based on the one-to-one correspondence between the images and the lights themselves.

[0151] In step S1430, the brightness of the LED display screen is corrected based on the luminous flux information corresponding to each lamp point. For example, after obtaining the luminous flux information corresponding to each lamp point of the LED display screen, the luminous flux information can be input into the correction module to correct the brightness of the LED display screen.

[0152] It should be understood that the methods in the embodiments of this application can be applied not only to brightness correction, but also to various other application scenarios such as color correction, thermal correction, full grayscale correction, hybrid screen splicing correction, secondary correction, low grayscale correction, and coupled screen correction.

[0153] For thermal correction, the methods for obtaining optical data of both the cold screen image and the hot screen image of the thermal compensation coefficient can be the methods described in the embodiments of this application.

[0154] For full grayscale correction, the optical data of each grayscale level among the acquired grayscale levels can be obtained using the method described in the embodiments of this application.

[0155] For hybrid screen splicing correction, the hybrid screen refers to a screen spliced ​​together by cabinets or modules of different specifications, such as LCD and LED splicing, or LED splicing with different pixel pitches, etc.

[0156] For low gray correction and coupling screen correction, it is necessary to control the screen to light up point by point and then use the method in this application to extract optical data.

[0157] The following is combined with Figure 15 This application describes the method for evaluating / calibrating LED displays provided in its embodiments from the perspective of software code or processor. Figure 15 The method shown can be executed, for example, by the processor or software system of the evaluation / calibration device mentioned above. Figure 15 The relevant concepts in this method have already been explained in detail above and will not be repeated here. Therefore, Figure 15 For any parts of the corresponding embodiments that are not described in detail, please refer to the preceding text.

[0158] See Figure 15 The method includes steps S1510 and S1520.

[0159] In step S1510, an image of all target light points in the lit state is obtained, wherein the target light points are red, green or blue light points in part or all of the display area of ​​the LED display screen, and the image of the target light points in the light point image is in a sticky state. The sticky state is used to indicate that adjacent light points in the target light points are in an imaging state without dark bands separating them in the light point image.

[0160] In step S1520, evaluation information and / or calibration information of the LED display screen are obtained based on the lamp point image. The evaluation information is used to evaluate the display quality of the LED display screen, and the calibration information is used to correct the brightness and / or chromaticity of the LED display screen.

[0161] In some embodiments, the imaging of the target light point in the light point image is in a state of adhesion, including: the imaging of adjacent light points in the target light point in the light point image is in a state of adjacency or overlap.

[0162] In some embodiments, the overlap of the images of adjacent light points is between 10% and 80%; and / or the difference between the maximum and minimum brightness in the light point image is between 10% and 50%; and / or the difference between the maximum and minimum grayscale in the light point image is between 10% and 50%; and / or the difference between the maximum and minimum DN value in the light point image is between 10% and 50%.

[0163] In some embodiments, the LED display screen includes a plurality of splicing units, and the correction information is also used to correct the gaps between the plurality of splicing units.

[0164] In some embodiments, the correction information includes correction parameters corresponding to the target light point, and the correction parameters corresponding to the target light point are also used to correct the gaps between the plurality of splicing units.

[0165] In some embodiments, step S1520 may include: obtaining evaluation information and / or calibration information of the LED display screen from the LED dot image based on the LED dot arrangement information of the LED display screen.

[0166] In some embodiments, obtaining evaluation information and / or calibration information of the LED display screen from the LED dot image based on the LED dot arrangement information includes: determining the correspondence between the target LED dot and the pixels in the LED dot image based on the LED dot arrangement information; determining the optical information corresponding to the target LED dot based on the correspondence between the target LED dot and the pixels in the LED dot image; and obtaining the evaluation information and / or calibration information of the LED display screen based on the optical information corresponding to the target LED dot.

[0167] In some embodiments, determining the correspondence between the target light point and the pixels in the light point image based on the light point layout information of the LED display screen includes: sampling the light point image based on the light point layout information of the LED display screen, such that the pixels in the sampled image correspond one-to-one with the target light point.

[0168] In some embodiments, Figure 15 The method may further include: acquiring a calibration image presented by the LED display screen, the calibration image being used to locate the positions of multiple partitions within the LED display screen in the lamp image; step S1520 may include: acquiring evaluation information and / or calibration information of the LED display screen based on the lamp image and the calibration image.

[0169] In some embodiments, the light spot image includes a first light spot image and a second light spot image, the first light spot image and the second light spot image corresponding to light spots of different colors within the target display area, and the calibration image includes a first calibration image corresponding to the first light spot image and a second calibration image corresponding to the second light spot image, wherein the first calibration image and the second calibration image are different.

[0170] In some embodiments, the calibration image includes multiple patterns corresponding to the multiple partitions, and the multiple patterns are alternating light and dark patterns.

[0171] In some embodiments, the plurality of partitions are all rectangular in shape.

[0172] In some embodiments, obtaining the evaluation information and / or calibration information of the LED display screen based on the lamp point image and the calibration image includes: dividing the lamp point image into multiple images corresponding one-to-one with the multiple partitions based on the calibration image; determining the optical information corresponding to the multiple partitions based on the multiple images; and obtaining the evaluation information and / or calibration information of the LED display screen based on the optical information corresponding to the multiple partitions.

[0173] In some embodiments, the plurality of images includes a first image, the plurality of partitions includes a first partition corresponding to the first image, and determining the optical information corresponding to the plurality of partitions based on the plurality of images includes: determining the correspondence between the target light point in the first partition and the pixel in the first image based on the light point arrangement information of the first partition; and determining the optical information corresponding to the target light point in the first partition based on the correspondence between the target light point in the first partition and the pixel in the first image.

[0174] In some embodiments, determining the correspondence between the target light point in the first partition and the pixel in the first image based on the light point layout information of the first partition includes: sampling the first image based on the light point layout information of the first partition, such that the pixels in the sampled image correspond one-to-one with the target light point in the first partition.

[0175] In some embodiments, prior to step S1520, Figure 15 The method may further include: performing a perspective transformation on the light spot image to correct the shape of the light spot image to a rectangle.

[0176] In some embodiments, Figure 15 The method may further include: presenting indication information on the image preview interface of the camera, the indication information being used to indicate the minimum size of the preview image of the light spot image.

[0177] In some embodiments, the indication information includes a rectangular area displayed on the image preview interface, and the indication information is used to indicate that the minimum size of the preview image needs to be greater than the size corresponding to the rectangular area.

[0178] In some embodiments, the lamp arrangement information is resolution information.

[0179] In some embodiments, the optical information includes one or more of the following: luminous flux information, luminance information, and chromaticity information.

[0180] Figure 16 This is a schematic diagram of an apparatus for evaluating / calibrating an LED display screen, provided as an embodiment of this application. The apparatus 1600 may include components for performing... Figure 15 The method comprises modules. The device 1600 includes a first acquisition module 1610 and a second acquisition module 1620.

[0181] The first acquisition module 1610 can be used to acquire an image of all target light points in an illuminated state. The target light points are red, green, or blue light points within part or all of the display area of ​​the LED display screen. The images of the target light points in the light point image are in a connected state, which indicates that adjacent light points in the target light points are in an imaging state without dark bands separating them in the light point image.

[0182] The second acquisition module 1620 can be used to acquire evaluation information and / or calibration information of the LED display screen based on the lamp point image. The evaluation information is used to evaluate the display quality of the LED display screen, and the calibration information is used to correct the brightness and / or chromaticity of the LED display screen.

[0183] In some embodiments, the imaging of the target light point in the light point image is in a state of adhesion, including: the imaging of adjacent light points in the target light point in the light point image is in a state of adjacency or overlap.

[0184] In some embodiments, the overlap of the images of adjacent light points is between 10% and 80%; and / or the difference between the maximum and minimum brightness in the light point image is between 10% and 50%; and / or the difference between the maximum and minimum grayscale in the light point image is between 10% and 50%; and / or the difference between the maximum and minimum DN value in the light point image is between 10% and 50%.

[0185] In some embodiments, the LED display screen includes a plurality of splicing units, and the correction information is also used to correct the gaps between the plurality of splicing units.

[0186] In some embodiments, the correction information includes correction parameters corresponding to the target light point, and the correction parameters corresponding to the target light point are also used to correct the gaps between the plurality of splicing units.

[0187] In some embodiments, the second acquisition module 1620 may be used to: acquire evaluation information and / or calibration information of the LED display screen from the light spot image based on the light spot arrangement information of the LED display screen.

[0188] In some embodiments, the second acquisition module 1620 may be used to: determine the correspondence between the target light point and the pixels in the light point image based on the light point arrangement information of the LED display screen; determine the optical information corresponding to the target light point based on the correspondence between the target light point and the pixels in the light point image; and acquire the evaluation information and / or calibration information of the LED display screen based on the optical information corresponding to the target light point.

[0189] In some embodiments, the second acquisition module 1620 may be used to: sample the light spot image according to the light spot arrangement information of the LED display screen, so that the pixels in the sampled image correspond one-to-one with the target light spot.

[0190] In some embodiments, the first acquisition module 1620 may further be used to: acquire a calibration image presented by the LED display screen, the calibration image being used to locate the positions of multiple partitions within the LED display screen in the lamp image; the second acquisition module 1620 may be used to: acquire evaluation information and / or calibration information of the LED display screen based on the lamp image and the calibration image.

[0191] In some embodiments, the light spot image includes a first light spot image and a second light spot image, the first light spot image and the second light spot image corresponding to light spots of different colors within the target display area, and the calibration image includes a first calibration image corresponding to the first light spot image and a second calibration image corresponding to the second light spot image, wherein the first calibration image and the second calibration image are different.

[0192] In some embodiments, the calibration image includes multiple patterns corresponding to the multiple partitions, and the multiple patterns are alternating light and dark patterns.

[0193] In some embodiments, the plurality of partitions are all rectangular in shape.

[0194] In some embodiments, the second acquisition module 1620 may be used to: divide the lamp point image into multiple images corresponding one-to-one with the multiple partitions according to the calibration image; determine the optical information corresponding to the multiple partitions according to the multiple images; and acquire the evaluation information and / or calibration information of the LED display screen according to the optical information corresponding to the multiple partitions.

[0195] In some embodiments, the plurality of images includes a first image, and the plurality of partitions includes a first partition corresponding to the first image. The second acquisition module 1620 can be used to: determine the correspondence between the target light point in the first partition and the pixel in the first image based on the light point arrangement information of the first partition; and determine the optical information corresponding to the target light point in the first partition based on the correspondence between the target light point in the first partition and the pixel in the first image.

[0196] In some embodiments, the second acquisition module 1620 may be used to: sample the first image according to the light spot arrangement information of the first partition, so that the pixels in the sampled image correspond one-to-one with the target light spot in the first partition.

[0197] In some embodiments, Figure 16 The device may further include a transformation module. The transformation module is used to perform perspective transformation on the light spot image to correct the shape of the light spot image to a rectangle.

[0198] In some embodiments, Figure 16 The device may also include a presentation module. The presentation module is used to present indication information on the camera's image preview interface, the indication information indicating the minimum size of the preview image of the light spot image.

[0199] In some embodiments, the indication information includes a rectangular area displayed on the image preview interface, and the indication information is used to indicate that the minimum size of the preview image needs to be greater than the size corresponding to the rectangular area.

[0200] In some embodiments, the lamp arrangement information is resolution information.

[0201] In some embodiments, the optical information includes one or more of the following: luminous flux information, luminance information, and chromaticity information.

[0202] Figure 17 This is a schematic diagram of a device for evaluating / calibrating an LED display screen, provided in another embodiment of this application. Figure 17 The device 1700 may include a memory 1710 and a processor 1720. The memory 1710 may be used to store a program. The processor 1720 may be used to execute the program stored in the memory to perform actions such as... Figure 15 The method shown.

[0203] It should be understood that in the various embodiments of this application, the order of the above-mentioned processes does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0204] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0205] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0206] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0207] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can read, or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., digital video disc (DVD)), or a semiconductor medium (e.g., solid-state disk (SSD)).

[0208] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for evaluating / calibrating LED displays, characterized in that, include: Controlling all target lights within part or all of the display area of ​​the LED display screen to be lit up, so as to perform non-interval sampling of the target lights, wherein the target lights are one or more of red lights, green lights, and blue lights; The camera parameters are adjusted so that the images of the target lights are in a state of adhesion. The state of adhesion is used to indicate that the adjacent lights in the target lights are in an imaging state without dark bands separating them. After the camera parameters are adjusted, the camera is controlled to take a picture of the LED display screen to obtain the image of the light point corresponding to the target light point; Based on the lamp image, evaluation information and / or correction information of the LED display screen are obtained to evaluate and / or correct the display defects of the LED display screen without excluding mutual interference of the light emission of the lamps in the LED display screen. The evaluation information is used to evaluate the display quality of the LED display screen, and the correction information is used to correct the brightness and / or color of the LED display screen. Wherein, the imaging of the target light point is in an adhered state, including: the imaging of adjacent light points in the target light point is in an adjacent state or an overlapping state. The overlap of the images of adjacent light points is between 10% and 80%.

2. The method according to claim 1, characterized in that, The difference between the maximum and minimum brightness in the light spot image is between 10% and 50%; and / or The difference between the maximum and minimum gray levels in the light spot image is between 10% and 50%; and / or The difference between the maximum and minimum DN values ​​in the light spot image is between 10% and 50%.

3. The method according to claim 1, characterized in that, The LED display screen includes multiple splicing units, and the correction information is also used to correct the gaps between the multiple splicing units.

4. The method according to claim 3, characterized in that, The correction information includes correction parameters corresponding to the target light point, and the correction parameters corresponding to the target light point are also used to correct the gaps between the multiple splicing units.

5. The method according to claim 1, characterized in that, The step of obtaining the evaluation information and / or calibration information of the LED display screen based on the light spot image includes: Based on the LED display screen's lamp arrangement information, the evaluation information and / or calibration information of the LED display screen are obtained from the lamp image.

6. The method according to claim 5, characterized in that, The step of obtaining the evaluation information and / or calibration information of the LED display screen from the LED dot image based on the LED dot arrangement information includes: Based on the LED display screen's lamp arrangement information, determine the correspondence between the target lamp and the pixels in the lamp image; Based on the correspondence between the target light point and the pixels in the light point image, the optical information corresponding to the target light point is determined; Based on the optical information corresponding to the target light point, obtain the evaluation information and / or calibration information of the LED display screen.

7. The method according to claim 6, characterized in that, Determining the correspondence between the target light point and the pixels in the light point image based on the light point layout information of the LED display screen includes: Based on the LED display screen's light dot arrangement information, the light dot image is sampled so that the pixels in the sampled image correspond one-to-one with the target light dot.

8. The method according to claim 1, characterized in that, After adjusting the camera parameters, the method further includes: The LED display screen is controlled to display a calibration image, which is used to locate the positions of multiple zones within the LED display screen in the light spot image; The camera is controlled to capture the calibration image, thereby obtaining a calibration image of the target display area; The step of obtaining the evaluation information and / or calibration information of the LED display screen based on the light spot image includes: Based on the light spot image and the calibration image, obtain the evaluation information and / or calibration information of the LED display screen.

9. The method according to claim 8, characterized in that, The light spot image includes a first light spot image and a second light spot image, the first light spot image and the second light spot image corresponding to light spots of different colors in the target display area, the calibration image includes a first calibration image corresponding to the first light spot image and a second calibration image corresponding to the second light spot image, the first calibration image and the second calibration image are different.

10. The method according to claim 8, characterized in that, The calibration image includes multiple patterns corresponding to the multiple partitions, and the multiple patterns are alternating patterns of light and dark.

11. The method according to claim 10, characterized in that, All of the partitions are rectangular in shape.

12. The method according to claim 8, characterized in that, The step of obtaining the evaluation information and / or calibration information of the LED display screen based on the lamp point image and the calibration image includes: Based on the calibration image, the light spot image is divided into multiple images that correspond one-to-one with the multiple partitions; Based on the multiple images, determine the optical information corresponding to the multiple partitions respectively; Based on the optical information corresponding to the multiple partitions, the evaluation information and / or calibration information of the LED display screen are obtained.

13. The method according to claim 12, characterized in that, The plurality of images includes a first image, and the plurality of partitions includes a first partition corresponding to the first image. The step of determining the optical information corresponding to the multiple partitions based on the multiple images includes: Based on the light distribution information of the first partition, determine the correspondence between the target light points in the first partition and the pixels in the first image; Based on the correspondence between the target light point in the first partition and the pixels in the first image, the optical information corresponding to the target light point in the first partition is determined.

14. The method according to claim 13, characterized in that, The step of determining the correspondence between the target light points in the first partition and the pixels in the first image based on the light point layout information of the first partition includes: Based on the light distribution information of the first partition, the first image is sampled so that the pixels in the sampled image correspond one-to-one with the target light points in the first partition.

15. The method according to claim 1, characterized in that, Before obtaining the evaluation information and / or calibration information of the LED display screen based on the light spot image, the method further includes: A perspective transformation is performed on the light spot image to correct its shape into a rectangle.

16. The method according to claim 1, characterized in that, The method further includes: The camera's image preview interface displays instruction information, which limits the size of the preview image of the light spot in the image preview interface.

17. The method according to claim 16, characterized in that, The indication information includes a rectangular area displayed on the image preview interface, and the indication information is used to indicate that the boundary of the preview image needs to reach or approach the boundary of the rectangular area.

18. The method according to claim 5, 6, 7, 13 or 14, characterized in that, The lamp arrangement information is resolution information.

19. A system for evaluating / calibrating LED displays, characterized in that, include: A camera for capturing images on the LED display screen; An evaluation / calibration device for processing images captured by the camera to perform the method as described in any one of claims 1-18.

20. A method for evaluating / calibrating an LED display screen, characterized in that, include: Acquire an image of all target light points in a lit state, wherein the target light points are one or more of red, green or blue light points in part or all of the display area of ​​the LED display screen, and the image of the target light points in the light point image is in a sticky state, the sticky state is used to indicate that adjacent light points in the target light points are in an imaging state without dark bands separating them in the light point image; Based on the lamp image, evaluation information and / or correction information of the LED display screen are obtained to evaluate and / or correct the display defects of the LED display screen without excluding mutual interference of the light emission of the lamps in the LED display screen. The evaluation information is used to evaluate the display quality of the LED display screen, and the correction information is used to correct the brightness and / or color of the LED display screen. Wherein, the image of the target light point in the light point image is in a state of adhesion, including: the images of adjacent light points in the target light point in the light point image are in a state of adjacency or overlap. Wherein, obtaining the evaluation information and / or calibration information of the LED display screen based on the light spot image includes: Based on the LED display screen's lamp arrangement information, the evaluation information and / or calibration information of the LED display screen are obtained from the lamp image.

21. The method according to claim 20, characterized in that, The overlap of the images of adjacent light points is between 10% and 80%; and / or The difference between the maximum and minimum brightness in the light spot image is between 10% and 50%; and / or The difference between the maximum and minimum gray levels in the light spot image is between 10% and 50%; and / or The difference between the maximum and minimum DN values ​​in the light spot image is between 10% and 50%.

22. The method according to claim 20, characterized in that, The LED display screen includes multiple splicing units, and the correction information is also used to correct the gaps between the multiple splicing units.

23. The method according to claim 22, characterized in that, The correction information includes correction parameters corresponding to the target light point, and the correction parameters corresponding to the target light point are also used to correct the gaps between the multiple splicing units.

24. The method according to claim 20, characterized in that, The step of obtaining the evaluation information and / or calibration information of the LED display screen from the LED dot image based on the LED dot arrangement information includes: Based on the LED display screen's lamp arrangement information, determine the correspondence between the target lamp and the pixels in the lamp image; Based on the correspondence between the target light point and the pixels in the light point image, the optical information corresponding to the target light point is determined; Based on the optical information corresponding to the target light point, obtain the evaluation information and / or calibration information of the LED display screen.

25. The method according to claim 24, characterized in that, Determining the correspondence between the target light point and the pixels in the light point image based on the light point layout information of the LED display screen includes: Based on the LED display screen's light dot arrangement information, the light dot image is sampled so that the pixels in the sampled image correspond one-to-one with the target light dot.

26. The method according to claim 20, characterized in that, The method further includes: A calibration image presented by the LED display screen is obtained, and the calibration image is used to locate the positions of multiple partitions within the LED display screen in the light spot image; The step of obtaining the evaluation information and / or calibration information of the LED display screen based on the light spot image includes: Based on the light spot image and the calibration image, obtain the evaluation information and / or calibration information of the LED display screen.

27. The method according to claim 26, characterized in that, The light spot image includes a first light spot image and a second light spot image, the first light spot image and the second light spot image corresponding to light spots of different colors in the target display area, the calibration image includes a first calibration image corresponding to the first light spot image and a second calibration image corresponding to the second light spot image, the first calibration image and the second calibration image are different.

28. The method according to claim 26, characterized in that, The calibration image includes multiple patterns corresponding to the multiple partitions, and the multiple patterns are alternating patterns of light and dark.

29. The method according to claim 28, characterized in that, All of the partitions are rectangular in shape.

30. The method according to claim 26, characterized in that, The step of obtaining the evaluation information and / or calibration information of the LED display screen based on the lamp point image and the calibration image includes: Based on the calibration image, the light spot image is divided into multiple images that correspond one-to-one with the multiple partitions; Based on the multiple images, determine the optical information corresponding to the multiple partitions respectively; Based on the optical information corresponding to the multiple partitions, the evaluation information and / or calibration information of the LED display screen are obtained.

31. The method according to claim 30, characterized in that, The plurality of images includes a first image, and the plurality of partitions includes a first partition corresponding to the first image. The step of determining the optical information corresponding to the multiple partitions based on the multiple images includes: Based on the light distribution information of the first partition, determine the correspondence between the target light points in the first partition and the pixels in the first image; Based on the correspondence between the target light point in the first partition and the pixels in the first image, the optical information corresponding to the target light point in the first partition is determined.

32. The method according to claim 31, characterized in that, The step of determining the correspondence between the target light points in the first partition and the pixels in the first image based on the light point layout information of the first partition includes: Based on the light distribution information of the first partition, the first image is sampled so that the pixels in the sampled image correspond one-to-one with the target light points in the first partition.

33. The method according to claim 20, characterized in that, Before obtaining the evaluation information and / or calibration information of the LED display screen based on the light spot image, the method further includes: A perspective transformation is performed on the light spot image to correct its shape into a rectangle.

34. The method according to claim 20, characterized in that, The method further includes: The camera's image preview interface displays instruction information that limits the size of the preview image of the light spot in the image preview interface.

35. The method according to claim 34, characterized in that, The indication information includes a rectangular area displayed on the image preview interface, and the indication information is used to indicate that the boundary of the preview image needs to reach or approach the boundary of the rectangular area.

36. The method according to claim 20, 24, 25, 31 or 32, characterized in that, The lamp arrangement information is resolution information.

37. An apparatus for evaluating / calibrating an LED display screen, characterized in that, Includes a module for performing the method as described in any one of claims 20-36.

38. An apparatus for evaluating / calibrating an LED display screen, characterized in that, include: Memory, used to store programs; A processor for executing a program stored in the memory to perform the method as described in any one of claims 20-36.

39. A computer-readable storage medium, characterized in that, It contains a program for performing the method as described in any one of claims 20-36.

40. A display screen control device, characterized in that, include: A memory for storing correction coefficients, said correction coefficients being obtained based on target information, said target information being obtained based on the method of any one of claims 20-36; The processor is used to call the correction coefficients stored in the memory to calibrate the display screen.

Images