Projector automatic screen entering method, device, equipment and medium

Abstract

The invention relates to the technical field of projection, in particular to an automatic screen entering method and device for a projector, equipment and a medium, and the method comprises the steps: obtaining an actual projection image corresponding to a preset calibration image based on the preset calibration image projected by the projector, carrying out the coordinate conversion calculation of the actual projection image, and obtaining a standard projection drawing; the method comprises the steps of preprocessing a standard projection drawing, determining a target projection curtain area in a target edge drawing after preprocessing the standard projection drawing, and determining angular point coordinates of a curtain contour in an image coordinate system according to the curtain contour of the target projection curtain area, so that a projector performs projection based on the angular point coordinates, and then a projection picture of the projector can be quickly and accurately projected into a screen. And the stability of the screen entering effect is greatly improved.

Description

Technical Field

[0001] The present invention relates to the field of projection technology, and in particular to a method, device, equipment and medium for automatically entering a projector screen. Background Art

[0002] A projector is a device that projects the image input into its own optical lens onto a wall or screen through optical projection, and the area on the wall or screen covered by the projector's light is called the projection area. When using a screen for projection, it is easy to have a problem where the projection area does not match the screen.

[0003] The existing technology often uses deep learning methods to obtain the coordinates of the corner points of the screen area, and then automatically adjusts the positions of the four corner points of the projection area to make the projection area match the projection screen. However, the deep learning method is unstable when there is a complex background in the area around the screen, and the screen may be entered incorrectly, thereby reducing the accuracy of the projector's automatic screen entry. Therefore, how to make the projected image of the projector enter the screen quickly and accurately has become a technical problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0004] Based on this, it is necessary to provide a method, device, equipment and medium for automatic screen entry of a projector to address the above technical problems, so that the projection image of the projector can enter the screen quickly and accurately, thereby improving the stability of the screen entry effect.

[0005] A first aspect of an embodiment of the present application provides a method for automatically entering a screen for a projector, the method comprising: Based on a preset calibration image projected by a projector, obtaining an actual projection image corresponding to the preset calibration image; Performing coordinate transformation calculation on the actual projection image to obtain a standard projection image; Obtaining a target edge map after preprocessing the standard projection map, and determining a target projection screen area in the target edge map; According to the screen contour of the target projection screen area, the corner point coordinates of the screen contour in the image coordinate system are determined, so that the projector performs projection based on the corner point coordinates.

[0006] A second aspect of an embodiment of the present application provides a projector automatic screen entry device, the projector automatic screen entry device comprising: An acquisition module, configured to acquire an actual projection image corresponding to a preset calibration image based on a preset calibration image projected by a projector; A calculation module, used for performing coordinate transformation calculation on the actual projection image to obtain a standard projection image; A determination module, used to obtain a target edge map after preprocessing the standard projection map, and determine a target projection screen area in the target edge map; The projection module is used to determine the corner point coordinates of the screen outline in the image coordinate system according to the screen outline of the target projection screen area, so that the projector performs projection based on the corner point coordinates.

[0007] In a third aspect, an embodiment of the present invention provides a computer device, comprising a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the processor implements the projector automatic screen entry method as described in the first aspect when executing the computer program.

[0008] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the projector automatic screen entry method as described in the first aspect is implemented.

[0009] In summary, the present invention provides a method, device, equipment and medium for automatically entering a projector into a screen, by obtaining an actual projection image corresponding to a preset calibration image based on a preset calibration image projected by the projector, performing coordinate transformation calculation on the actual projection image, obtaining a standard projection image, obtaining a target edge map after preprocessing the standard projection image, and determining a target projection screen area in the target edge map, and determining the corner point coordinates of the screen outline in the image coordinate system according to the screen outline of the target projection screen area, so that the projector can project based on the corner point coordinates. The present application obtains an actual projection image corresponding to a preset calibration image based on a preset calibration image projected by the projector, performs coordinate transformation calculation on the actual projection image, obtaining a standard projection image, and determining the target projection screen area in the target edge map after preprocessing the standard projection image, so as to determine the corner point coordinates of the screen outline in the image coordinate system, so that the projector can project based on the corner point coordinates, and thus the projection picture of the projector can enter the screen quickly and accurately, greatly improving the stability of the entry effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0011] Figure 1 This is a schematic diagram of an application environment of a projector automatic screen entry method provided by an embodiment of the present invention; Figure 2It is a flowchart of a method for automatically entering a projector screen provided by an embodiment of the present invention; Figure 3 is a schematic diagram of a preset calibration image in a method for automatically entering a projector into a screen provided by an embodiment of the present invention; Figure 4 is a schematic diagram of an actual projected image in a method for automatically entering a projector into a screen provided by an embodiment of the present invention; Figure 5 It is a schematic diagram of a standard projection image in a method for automatically entering a projector into a screen provided by an embodiment of the present invention; Figure 6 is a schematic diagram of an initial edge map in a method for automatic screen entry of a projector provided by an embodiment of the present invention; Figure 7 It is a schematic diagram of a target edge map (without feature point area) in a method for automatic projector screen entry provided by an embodiment of the present invention; Figure 8 It is a schematic diagram of a target edge map (closing operation) in a method for automatic projector screen entry provided by an embodiment of the present invention; Fig. 9 is a schematic diagram of a target projection screen area in a method for automatically entering a projector into a screen provided by an embodiment of the present invention; Fig.10 is a schematic diagram of a screen outline in a method for automatically entering a projector into a screen provided by an embodiment of the present invention; Fig.11 It is a schematic diagram of calculating an iterative endpoint fitting algorithm and a threshold value T in a method for automatically entering a projector into a screen provided by an embodiment of the present invention; Fig.12 is a schematic diagram of target corner point coordinates in a method for automatic projector screen entry provided by an embodiment of the present invention; Fig.13 It is an example diagram of the target corner point coordinates on the standard projection diagram in a method for automatic projector screen entry provided by an embodiment of the present invention; Fig.14 It is a schematic diagram of distinguishing the relative positions of four corner points in a method for automatically entering a projector into a screen provided by an embodiment of the present invention; Fig.15 It is a structural schematic diagram of an automatic screen entry device for a projector provided by an embodiment of the present invention; Fig.16 It is a structural schematic diagram of a computer device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0012] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0013] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0014] It should also be understood that the term "and / or" used in the present description and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0015] As used in the present specification and the appended claims, the term “if” may be interpreted as “when” or “uponce” or “in response to determining”, depending on the context. Similarly, the phrases “if it is determined” or “if matched to [described condition or event]” may be interpreted as meaning “upon determination” or “in response to determination” or “uponce matched to [described condition or event]” or “in response to matching to [described condition or event]”, depending on the context.

[0016] In addition, in the description of the present specification and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.

[0017] References to "one embodiment" or "some embodiments" etc. described in the specification of the present invention mean that one or more embodiments of the present invention include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the statements "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0018] It should be understood that the order of execution of the steps in the following embodiments does not imply a precedence 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 the present invention.

[0019] In order to illustrate the technical solution of the present invention, specific embodiments are provided below for illustration.

[0020] The projector automatic screen entry method provided in the embodiment of the present application can be applied to Figure 1 In the application environment shown. The projector projects the picture onto the projection screen for display. The projector can acquire the image of the projection area through the image acquisition unit arranged thereon to obtain the actual projection image. The projector can execute the projector automatic screen entry method in each embodiment of the present application based on the actual projection image to achieve matching of the projected picture with the projection screen. Among them, the projector can be a device specially used for projection, or it can be a terminal or other device with projection function. For example: the projector can be an ultra-short-throw projection device. The projection screen is a screen used to present the picture projected by the projection device.

[0021] In some embodiments, Figure 2 FIG. 1 is a flow chart of a method for automatically entering a projector screen according to an embodiment of the present invention. Figure 1 Taking the projector in as an example, the projector automatic screen entry method may include the following steps.

[0022] S201: Based on a preset calibration image projected by a projector, an actual projection image corresponding to the preset calibration image is acquired.

[0023] In step S201, the preset calibration image needs to include the preset feature points to be measured, and the actual projection image may include the projection screen and the complex background around the screen. The projector projects the preset calibration image, and then uses the image acquisition unit to acquire an image of the projection area to obtain the actual projection image. The image acquisition unit may be a hardware unit such as a camera for image acquisition. When the present application receives an automatic screen entry instruction, the projector is started, and the projector projects the preset calibration image outward through the optical machine, and the actual projection image of the preset calibration image is captured in real time through the camera of the projector. Among them, Figure 3 It is a preset calibration image projected by the projector onto the projection plane through an optical machine. Its size is (L, H). In the central area of ​​the image, there are m and n feature points in rows and columns respectively, and m>=2, n>=2 are required. It should be noted that the feature points can be checkerboard corner points or other custom feature points, and this application does not impose any restrictions on this. Figure 4 This is an actual projection image captured in real time by the projector camera. In this image, you can see the projection screen and the complex background around the screen.

[0024] In the implementation of this application, the preset calibration image is the picture to be projected in the projector, and the resolution of the picture is generally but not limited to 1920*1080. When the user thinks that automatic screen entry is required in the current situation, he presses the button on the remote control to issue an automatic screen entry command. The projector receives the automatic screen entry command, firstly ensures that the projected image can be displayed relatively clearly and brightly through automatic focus, then reminds the user to place the feature point area of ​​the projected preset calibration image within the range of the screen, and then uses the image acquisition unit to acquire the actual projection image, thereby improving the efficiency and accuracy of acquiring the actual projection image.

[0025] S202: Perform coordinate transformation calculation on the actual projection image to obtain a standard projection image.

[0026] In step S202, the preset calibration image of the projector is projected based on its built-in coordinate system. If the actual projection image is obtained by shooting through the image acquisition module of the projector, it is shot based on the coordinate system under another viewing angle. Therefore, the coordinate system of the actual projection image and the preset calibration image is different. The present application obtains the normalized coordinates of the corresponding actual projection image through the preset calibration image. The preset calibration image is generally an image of known size and shape, containing known coordinate information. The image processing technology is used to detect and match the feature points of the actual projection image, find the feature points corresponding to the preset calibration image in the actual projection image, and then perform coordinate conversion calculation based on the found feature points and the corresponding preset calibration image coordinates to obtain the normalized coordinates of the actual projection image, and map all the pixels in the actual projection image according to the normalized coordinates to obtain a normalized projection map. In this way, based on the preset calibration image, the coordinate conversion calculation of the actual projection image can obtain a normalized projection map. It should be noted that the actual image processing and calculation process may be more complicated, and the specific implementation involves specific algorithms and technical selections, which need to be appropriately adjusted and optimized according to the specific situation.

[0027] As an optional embodiment, obtaining a standard projection diagram includes: Acquire the first feature point to be measured in the actual projection image and the second feature point to be measured in the preset calibration image, and arrange them according to the same arrangement rule; When the arrangement rules of the first feature points to be measured are consistent with those of the second feature points to be measured, calculating a coordinate transformation matrix from the actual projection image coordinate system to the preset calibration image coordinate system; Based on the coordinate transformation matrix, a standard projection image of the actual projection image in the preset calibration image coordinate system is determined.

[0028] Specifically, since the actual projection image returned by the camera is in a mirror image relationship with the actual situation, the actual projection image is first flipped horizontally, and then the feature points to be measured in the actual projection image after the horizontal flip are detected, and the feature points to be measured are arranged in sequence according to the size of the horizontal and vertical coordinates. The specific arrangement rule can be changed, as long as a certain order is maintained, and the arranged m×n feature points are called the first feature points to be measured, that is, C1. Continue to obtain the m×n second feature points to be measured in the preset calibration image, that is, C2. When the arrangement rule of the second feature point C2 to be measured is consistent with the arrangement rule of the first feature point C1 to be measured, the coordinate transformation matrix M from the actual projection image coordinate system to the preset calibration image coordinate system is calculated according to the correspondence between the feature points in C1 and C2. Then, M is applied to transform the actual projection image to the coordinate system of the preset calibration image, and at the same time, the (L, H) part that is consistent with the size of the preset calibration image is intercepted to obtain a standard projection image, such as Figure 5 Optionally, if the size of the canonical projection is transformed to , k>1, which can speed up the calculation of subsequent steps without affecting the obstacle avoidance results. Optionally, if the ambient light is too strong and the feature points to be measured cannot be detected in the actual projected image, the image contrast can be enhanced by gamma transformation to obtain the feature points to be measured in the image. The calculation formula is as follows: Among them, x is each pixel of the original image, y is each pixel of the image after gamma transformation, c is the grayscale scaling factor, which is 1, and γ is the adjustment constant, which is usually a value in the interval (1,2.5).

[0029] In an embodiment of the present application, the camera is calibrated, the intrinsic parameters and extrinsic parameters of the camera are calibrated in the calibration image, and the distortion parameters, intrinsic parameter matrix and extrinsic parameter matrix of the camera are obtained. Then, feature points of the actual projection image and the preset calibration image are extracted. For example, SIFT, SURF and other algorithms are used to match the feature points extracted from the actual projection image and the preset calibration image, and the corresponding relationship between them is found. The corresponding relationship is used to perform coordinate transformation calculations using a perspective transformation method or other methods, and the actual projection image is normalized to obtain a standardized projection image. This effectively avoids data errors caused by calibration errors, ensures the quality and credibility of the projection image, and facilitates subsequent in-depth analysis of the standardized projection image, thereby improving the efficiency of projection onto the screen.

[0030] S203: Obtain a target edge map after preprocessing the standard projection map, and determine a target projection screen area in the target edge map.

[0031] In step S203, the target edge map is obtained by preprocessing the standard projection image, including grayscale, denoising, edge enhancement and other processing, so that the target edge map can be better used for edge detection. , and the target projection screen area is determined.

[0032] As an optional embodiment, obtaining the target edge map after preprocessing the standard projection map includes: Performing standardization processing on the standard projection diagram to obtain a standardized standard projection diagram; According to the noise type of the standard projection image, filtering is performed on the standardized standard projection image to obtain a filtered standard projection image; Performing edge detection on the filtered canonical projection image to obtain an initial edge image; The initial edge map is subjected to edge elimination to obtain a target edge map.

[0033] Specifically, after obtaining the canonical projection map, the present application first preprocesses the canonical projection map. The required preprocessing steps are: standardization (0-255). By standardizing the canonical projection map, a standardized canonical projection map is obtained. According to the noise type of the canonical projection map, the standardized canonical projection map is filtered to obtain a filtered canonical projection map. The optional filtering steps are: median filtering, Gaussian filtering, and non-local mean filtering. After preprocessing, edge detection is performed on the filtered canonical projection map to obtain an initial edge map, such as Figure 6 As shown. Edges are detected on the preprocessed standard projection map using an edge detection algorithm (such as Canny edge detection). These edges usually represent the boundaries of objects. After obtaining the initial edge map, the initial edge map is edge-eliminated to obtain a target edge map, so that the target projection screen area can be determined in the target edge map later.

[0034] As an optional embodiment, performing edge elimination on the initial edge map to obtain a target edge map includes: Obtaining the regional position coordinates of the second feature point to be measured in the preset calibration image; Determining a target area of ​​a third feature point to be measured of the initial edge map according to the area position coordinates; The edge of the feature point area to be measured in the center of the target area is eliminated to obtain a target edge map.

[0035] Specifically, since the coordinate systems of the canonical projection image and the preset calibration image are consistent, the position coordinates of the feature point area to be measured can be directly recorded when preparing the preset calibration image. The target area of ​​the third feature point to be measured in the initial edge map is determined through the position coordinates of the area, and the outermost edge of the feature point area to be measured is retained. The edge of the feature point area to be measured in the center of the target area is eliminated, and then the target edge map (feature point area removed) is obtained, such as Figure 7 As shown. A closing operation with an iteration number of 2 is performed on the target edge map (the area without feature points) to connect the incomplete edge contours that may appear. The specific steps are "expansion → expansion → erosion → erosion" to obtain the target edge map (closing operation)", as shown Figure 8 shown.

[0036] As an optional embodiment, determining the target projection screen area in the target edge map includes: Obtaining a target edge map after preprocessing the canonical projection map; The target edge map is calculated based on a region growing algorithm to obtain a target projection screen region.

[0037] Specifically, after obtaining the target edge map after preprocessing the canonical projection map, a region growing algorithm is applied to the target edge map to find the target projection screen area, wherein the region growing algorithm is an image segmentation algorithm based on seed point growth, which is used to combine pixel points with similar features in the image into a region or object. The algorithm starts from the seed point, and merges adjacent pixel points into a region by continuously expanding adjacent pixel points until certain conditions are met and the growth stops. Since the automatic entry algorithm in the present invention agrees with the user that the region of the feature points to be measured in the projection falls within the screen, by recording the coordinates of the center position of the feature point region to be measured in the preset calibration image as , then the target edge graph (closed operation), Figure 8 In the figure, the coordinates of the center position of the feature point area to be measured are also Based on breadth-first search, the region growing algorithm of the image is implemented. Point is the seed point, and the four-connected region growth is performed on the target edge graph (closed operation) to obtain the target projection screen area. The result is as follows Fig. 9 shown.

[0038] In this embodiment, by using the edge detection algorithm to obtain the target edge image, the parameters can be set according to the shape and characteristics of the target to better detect the target edge image. For the extracted edges, edge connection or merging processing can be performed to reduce noise or breaks on the edges and ensure the integrity of the edges. Threshold segmentation, regional growth and other algorithms can be used to find the target projection screen area. Through edge detection and regional growth, the position of the target projection screen area can be accurately located to avoid errors, thereby improving processing efficiency, reducing manual intervention, and realizing the function of automatically processing the target screen area, so as to facilitate subsequent projection calibration and correction processing and optimize the visual effect of the projection image.

[0039] S104: Determine corner point coordinates of the screen outline in an image coordinate system according to the screen outline of the target projection screen area, so that the projector performs projection based on the corner point coordinates.

[0040] In step S104, after obtaining the target projection screen area, the target projection screen area is subjected to contour detection to find the continuous edge contour. The contour detection can be implemented using image processing libraries such as OpenCV, and then the screen contour of the target projection screen area is obtained. The screen contour is a rectangle in the real environment, but the image acquisition unit of the projector is at different use angles and positions. The screen contour curve in the acquired image is a closed curve similar to a quadrilateral. The four corner point coordinates corresponding to the quadrilateral on the screen contour curve are found, and then the relative positions of the corner point coordinates are determined. According to the relative positions of the corner point coordinates, the corner point coordinates are arranged in the order of (lower left, upper left, upper right, lower right), and the sorted corner point coordinates are provided to the projector so that the projector performs projection based on the corner point coordinates, thereby ensuring that the projection area matches the screen area. Through this step, we can determine the corner point coordinates in the image coordinate system according to the screen contour, so that the projector can quickly and accurately perform projection based on these corner point coordinates.

[0041] As an optional embodiment, determining the target corner coordinates of the curtain outline in the image coordinate system includes: Based on the curtain contour of the target projection curtain area, an iterative end point fitting algorithm is used to determine the initial corner point coordinates of the curtain contour; Based on the relative positions of the corner point coordinates, the corner point coordinates are arranged in a certain order so that the projector performs projection based on the corner point coordinates.

[0042] Specifically, after obtaining the target projection screen area, the outer contour of the area is extracted on the target projection screen area. The extracted outer contour of the target projection screen area is as follows: Fig.10As shown. Apply the iterative endpoint fitting algorithm on the curtain contour to find the four corner points on the curtain contour. The iterative endpoint fitting algorithm needs to determine the segmentation point distance threshold T. Since the curtain contour has different sizes and shapes, the segmentation point distance threshold T has different ranges of values ​​on different curtain contours, and is an indefinite threshold. In order to adapt to different curtain contours, the segmentation point distance T of the iterative endpoint fitting algorithm is set to T = α•L, where L is the circumference of the curtain contour and α is a fixed constant, and the indefinite threshold T is converted into the constant threshold α.

[0043] The selection process of the constant threshold is as follows: Fig.11 As shown in , in the iterative endpoint fitting algorithm, firstly, the distance r from point B to point A needs to be greater than T, and secondly, the distance d from point C to the line AB needs to be greater than T, and T should be smaller than r and d, so that the larger value can be taken. In this way, the irregular points on the contour can be avoided from affecting the result when the corner points of the curtain contour are successfully found as the segmentation points. The curtain contour is approximated as a rectangle for calculation, as shown in Fig.11 As shown, r>d>T, the perimeter L=2(m+n), the area equation of the triangle , and then get the following formula: Calculate the threshold , the projection screen ratio is usually m:n=16:9 or m:n=4:3. When m:n=16:9, 0<α<0.1569; when m:n=4:3, 0<α<0.1717. You can select a certain value within the range of α in combination with the actual test results. After applying the iterative endpoint fitting algorithm to the screen contour, it is necessary to determine whether the number of corner points obtained by the iterative endpoint fitting algorithm is 4. If not, output "no screen found", exit the program, and wait for the next screen entry command to be issued; if it is 4, continue to execute the steps of the projector automatic screen entry method, where, Fig.12 This is an example of the corner points of the curtain outline. Fig.13 The following is an example of the obtained curtain outline corner points on the standard projection diagram.

[0044] In the implementation of this application, after determining the corner point coordinates of the screen outline, it is also necessary to determine the relative position of the corner point coordinates, and then arrange the corner point coordinates in a certain order according to the relative position of the corner point coordinates, and provide the sorted corner point coordinates to the projector so that the projector can project based on the corner point coordinates to ensure that the projection area matches the screen area. , as the seed point of the region growing algorithm to find the curtain area, so The center position coordinate point must be within the curtain area, such as Fig.14 As shown. The coordinates of the four corner points are transformed to A virtual coordinate system with the coordinate origin as the coordinate system can determine the relative position of the corner point coordinates according to the coordinate quadrant in which the corner point is located, rearrange them in a specific order, and then input the sorted corner point coordinates into the projector to project a new projection area that adapts to the screen, wherein they are rearranged into four points (lower left, upper left, upper right, lower right).

[0045] In this embodiment, the corner point coordinates of the screen outline in the target projection screen area are determined according to the screen outline in the image coordinate system, and the relative positions of the corner point coordinates are determined. Then, according to the relative positions of the corner point coordinates, the corner point coordinates are arranged in a certain order, and the sorted corner point coordinates are provided to the projector, so that the projector can accurately project the image on the specified area of ​​the screen based on the corner point coordinates, thereby improving the projection quality and accuracy, ensuring that the projector can stably project the image into the target area during projection, avoiding projection offset or distortion, simplifying the operation of the projector, and greatly improving the accuracy and efficiency of projecting into the screen, thereby improving the overall user experience and visual effects.

[0046] In summary, the present invention provides a method, device, equipment and medium for automatically entering a projector into a screen, by obtaining an actual projection image corresponding to a preset calibration image based on a preset calibration image projected by the projector, performing coordinate transformation calculation on the actual projection image, obtaining a standard projection image, obtaining a target edge map after preprocessing the standard projection image, and determining a target projection screen area in the target edge map, and determining the corner point coordinates of the screen outline in the image coordinate system according to the screen outline of the target projection screen area, so that the projector can project based on the corner point coordinates. The present application obtains an actual projection image corresponding to a preset calibration image based on a preset calibration image projected by the projector, performs coordinate transformation calculation on the actual projection image, obtaining a standard projection image, and determining the target projection screen area in the target edge map after preprocessing the standard projection image, so as to determine the corner point coordinates of the screen outline in the image coordinate system, so that the projector can project based on the corner point coordinates, and thus the projection picture of the projector can enter the screen quickly and accurately, greatly improving the stability of the entry effect.

[0047] See also Fig.15 , Fig.15 Schematic diagram of the structure of the projector automatic screen entry device provided by the embodiment of the present invention. In this embodiment, the terminal includes various units for executing Figure 2 For details, please refer to the steps in the corresponding embodiment. Figure 2 as well as Figure 2 For the convenience of explanation, only the parts related to this embodiment are shown. Fig.15The projector automatic screen entry device 150 includes: an acquisition module 151, a calculation module 152, a determination module 153, and a projection module 154.

[0048] An acquisition module 151 is used to acquire an actual projection image corresponding to a preset calibration image based on the preset calibration image projected by the projector; A calculation module 152 is used to perform coordinate transformation calculation on the actual projection image to obtain a standard projection image; A determination module 153 is used to obtain a target edge map after preprocessing the standard projection map, and determine a target projection screen area in the target edge map; The projection module 154 is used to determine the corner point coordinates of the screen outline in the image coordinate system according to the screen outline of the target projection screen area, so that the projector performs projection based on the corner point coordinates.

[0049] Optionally, the calculation module 152 is specifically used for: Acquire the first feature point to be measured in the actual projection image and the second feature point to be measured in the preset calibration image, and arrange them according to the same arrangement rule; When the arrangement rules of the first feature points to be measured are consistent with those of the second feature points to be measured, calculating a coordinate transformation matrix from the actual projection image coordinate system to the preset calibration image coordinate system; Based on the coordinate transformation matrix, a standard projection image of the actual projection image in the preset calibration image coordinate system is determined.

[0050] Optionally, the determination module 153 is specifically configured to: Performing standardization processing on the standard projection diagram to obtain a standardized standard projection diagram; According to the noise type of the standard projection image, filtering is performed on the standardized standard projection image to obtain a filtered standard projection image; Performing edge detection on the filtered canonical projection image to obtain an initial edge image; The initial edge map is subjected to edge elimination to obtain a target edge map.

[0051] Optionally, the determination module 153 is further configured to: Obtaining the regional position coordinates of the second feature point to be measured in the preset calibration image; Determining a target area of ​​a third feature point to be measured of the initial edge map according to the area position coordinates; The edge of the feature point area to be measured in the center of the target area is eliminated to obtain a target edge map.

[0052] Optionally, the determination module 153 is further configured to: Obtaining a target edge map after preprocessing the canonical projection map; The target edge map is calculated based on a region growing algorithm to obtain a target projection screen region.

[0053] Optionally, the projection module 154 is specifically used for: Based on the screen contour of the target projection screen area, an iterative end point fitting algorithm is used to determine the coordinates of the corner points of the screen contour in the image coordinate system; Based on the relative positions of the corner point coordinates, the corner point coordinates are arranged in a certain order so that the projector performs projection based on the corner point coordinates.

[0054] It should be noted that the information interaction, execution process and other contents between the above-mentioned units are based on the same concept as the embodiment of the method of the present invention. Their specific functions and technical effects can be found in the method embodiment part and will not be repeated here.

[0055] Fig.16 Schematic diagram of the structure of a computer device provided by an embodiment of the present invention. Fig.16 As shown, the computer device of this embodiment includes: at least one processor ( Fig.16 Only one is shown in the figure), a memory, and a computer program stored in the memory and executable on at least one processor, wherein when the processor executes the computer program, the steps in any of the above-mentioned projector automatic screen entry method embodiments are implemented.

[0056] The computer device may include, but is not limited to, a processor and a memory. Those skilled in the art will appreciate that Fig.16 This is merely an example of a computer device and does not constitute a limitation on the computer device. The computer device may include more or fewer components than those shown in the figure, or a combination of certain components, or different components. For example, it may also include a network interface, a display screen, and an input device.

[0057] In one embodiment, a computer-readable storage medium is provided. When the instructions in the computer-readable storage medium are executed by a processor in a computer device, the computer device can execute the steps of any embodiment of a projector automatic screen entry method disclosed in the present invention, which will not be repeated here. The computer-readable storage medium can be non-volatile or volatile.

[0058] The processor may be a CPU, or other general-purpose processors, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0059] The memory includes a readable storage medium, an internal memory, etc., wherein the internal memory may be the memory of a computer device, and the internal memory provides an environment for the operation of the operating device and the computer-readable instructions in the readable storage medium. The readable storage medium may be a hard disk of a computer device, and in other embodiments, it may also be an external storage device of the computer device, for example, a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), etc. equipped on the computer device. Further, the memory may also include both an internal storage unit of the computer device and an external storage device. The memory is used to store operating devices, application programs, boot loaders (BootLoader), data, and other programs, such as program codes of computer programs, etc. The memory may also be used to temporarily store data that has been output or is to be output.

[0060] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0061] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated into a processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of the present invention. The specific working process of the units and modules in the above-mentioned device can refer to the corresponding process in the above-mentioned method embodiment, which will not be repeated here. If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium.

[0062] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A method for automatically entering a projector screen, characterized in that: include: Based on a preset calibration image projected by a projector, obtaining an actual projection image corresponding to the preset calibration image; Performing coordinate transformation calculation on the actual projection image to obtain a standard projection image; Obtaining a target edge map after preprocessing the standard projection map, and determining a target projection screen area in the target edge map; According to the screen contour of the target projection screen area, the corner point coordinates of the screen contour in the image coordinate system are determined, so that the projector performs projection based on the corner point coordinates.

2. The projector automatic screen entry method according to claim 1, characterized in that: The performing coordinate transformation calculation on the actual projection image to obtain a standard projection image includes: Acquire the first feature point to be measured in the actual projection image and the second feature point to be measured in the preset calibration image, and arrange them according to the same arrangement rule; When the arrangement rules of the first feature points to be measured are consistent with those of the second feature points to be measured, calculating a coordinate transformation matrix from the actual projection image coordinate system to the preset calibration image coordinate system; Based on the coordinate transformation matrix, a standard projection image of the actual projection image in the preset calibration image coordinate system is determined.

3. The projector automatic screen entry method according to claim 1, characterized in that: The step of obtaining the target edge map after preprocessing the standard projection map comprises: Performing standardization processing on the standard projection diagram to obtain a standardized standard projection diagram; According to the noise type of the standard projection image, filtering is performed on the standardized standard projection image to obtain a filtered standard projection image; Performing edge detection on the filtered canonical projection image to obtain an initial edge image; The initial edge map is subjected to edge elimination to obtain a target edge map.

4. The projector automatic screen entry method according to claim 3, characterized in that: The step of performing edge elimination on the initial edge map to obtain a target edge map includes: Obtaining the regional position coordinates of the second feature point to be measured in the preset calibration image; Determining a target area of ​​a third feature point to be measured of the initial edge map according to the area position coordinates; The edge of the feature point area to be measured in the center of the target area is eliminated to obtain a target edge map.

5. The projector automatic screen entry method according to claim 1, characterized in that: Determining the target projection screen area in the target edge map includes: Obtaining a target edge map after preprocessing the canonical projection map; The target edge map is calculated based on a region growing algorithm to obtain a target projection screen region.

6. The projector automatic screen entry method according to claim 1, characterized in that: The step of determining the corner point coordinates of the screen outline in the image coordinate system according to the screen outline of the target projection screen area, so that the projector performs projection based on the corner point coordinates, includes: Based on the screen contour of the target projection screen area, an iterative end point fitting algorithm is used to determine the coordinates of the corner points of the screen contour in the image coordinate system; Based on the relative positions of the corner point coordinates, the corner point coordinates are arranged in a certain order so that the projector performs projection based on the corner point coordinates.

7. A projector automatic screen entry device, characterized in that: include: An acquisition module, configured to acquire an actual projection image corresponding to a preset calibration image based on a preset calibration image projected by a projector; A calculation module, used for performing coordinate transformation calculation on the actual projection image to obtain a standard projection image; A determination module, used to obtain a target edge map after preprocessing the standard projection map, and determine a target projection screen area in the target edge map; The projection module is used to determine the corner point coordinates of the screen outline in the image coordinate system according to the screen outline of the target projection screen area, so that the projector performs projection based on the corner point coordinates.

8. The automatic screen entry device for a projector as claimed in claim 7, characterized in that: The calculation module comprises: Acquire the first feature point to be measured in the actual projection image and the second feature point to be measured in the preset calibration image, and arrange them according to the same arrangement rule; When the arrangement rules of the first feature points to be measured are consistent with those of the second feature points to be measured, calculating a coordinate transformation matrix from the actual projection image coordinate system to the preset calibration image coordinate system; Based on the coordinate transformation matrix, a standard projection image of the actual projection image in the preset calibration image coordinate system is determined.

9. A computer device, characterized in that: The computer device includes a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the projector automatic screen entry method as described in any one of claims 1 to 6 is implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the projector automatic screen entry method as described in any one of claims 1 to 6 is implemented.

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