Projection picture distortion correction method and system, computer device and storage medium

Abstract

The application relates to a projection picture distortion correction method and system, computer equipment and a storage medium. The method comprises the following steps: determining the first coordinates of each edge feature point of a reference pattern in a projection picture image in an image coordinate system; for each edge of the reference pattern in a first direction, selecting a target coordinate value closest to the center of the projection picture image in a second direction from the first coordinates of each edge feature point on the edge; replacing the coordinate value in the second direction of the first coordinates of each edge feature point on the edge with the target coordinate value to obtain the adjusted first coordinates of each edge feature point on the edge; converting the adjusted first coordinates into coordinates in a projection device coordinate system to obtain the target second coordinates of each edge feature point; and using the target second coordinates of each edge feature point to enable the projection device to correct the distortion of an original projection picture based on the target second coordinates. The method can correct the distortion of the projection picture.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of computers, and in particular to a projection picture distortion correction method and system, a computer device, and a storage medium. BACKGROUND

[0002] With the development of science and technology, various projection devices have emerged in an endless stream, bringing a lot of convenience to people's work and life. Due to the needs of some small-sized family households, ultra-short-focus projection devices have emerged as the times require. These projection devices can project a large screen picture at a very close distance from the wall, greatly reducing the space requirements of the projection device.

[0003] However, the ultra-short-focus projection device has some shortcomings. Since the light machine of the ultra-short-focus projection device generally has a large elevation angle to project the picture onto the wall, in the case that the wall is not flat enough, the projected picture is prone to distortion. Therefore, how to correct the distortion of the projection picture has become an important problem. SUMMARY

[0004] Therefore, it is necessary to provide a projection picture distortion correction method, system, device, computer device, computer readable storage medium, and computer program product capable of correcting the distortion of the projection picture.

[0005] In a first aspect, the present application provides a projection picture distortion correction method. The method comprises:

[0006] determining first coordinates of each edge feature point of a reference pattern in a projection picture image in an image coordinate system; the projection picture image is an image obtained by image acquisition on an original projection picture; the original projection picture is a projection picture obtained by projection of an original reference pattern by a projection device; the edge feature point is a feature point on the edge of the reference pattern in the projection picture image;

[0007] for each edge of the reference pattern in a first direction, selecting a target coordinate value in a second direction from the first coordinates of each edge feature point on the edge; the target coordinate value is the coordinate value closest to the center of the projection picture image in the coordinate values of the first coordinates of each edge feature point on the edge in the second direction; the first direction is the direction of one coordinate axis in the image coordinate system; the second direction is the direction of another coordinate axis in the image coordinate system;

[0008] replacing the coordinate values in the second direction of the first coordinates of each edge feature point on the edge with the target coordinate value to obtain the adjusted first coordinates of each edge feature point on the edge;

[0009] convert the adjusted first coordinates of each of the edge feature points into coordinates in a coordinate system of the projection device to obtain target second coordinates of each of the edge feature points in the coordinate system of the projection device; the target second coordinates of each of the edge feature points are used to cause the projection device to correct distortion of the original projection picture based on the target second coordinates.

[0010] In a second aspect, the present application further provides a projection picture distortion correction system. The system comprises a projection device, a control terminal and a server, wherein:

[0011] The projection device is configured to project based on an original reference pattern to obtain an original projection picture.

[0012] The control terminal is configured to perform image acquisition on the original projection picture to obtain a projection picture image.

[0013] The server is configured to determine first coordinates of each edge feature point of a reference pattern in the projection picture image in an image coordinate system; for each edge of the reference pattern in a first direction, select a target coordinate value in a second direction from the first coordinates of each edge feature point on the edge; replace the coordinate value in the second direction in the first coordinates of each edge feature point on the edge with the target coordinate value to obtain adjusted first coordinates of each edge feature point on the edge; convert the adjusted first coordinates of each of the edge feature points into coordinates in a coordinate system of the projection device to obtain target second coordinates of each of the edge feature points in the coordinate system of the projection device; the edge feature points are feature points on the edge of the reference pattern in the projection picture image; the target coordinate value is a coordinate value closest to the center of the projection picture image among the coordinate values in the second direction of the first coordinates of each of the edge feature points on the edge; the first direction is the direction of one coordinate axis in the image coordinate system; and the second direction is the direction of another coordinate axis in the image coordinate system.

[0014] The control terminal is further configured to obtain the target second coordinates of each of the edge feature points from the server and send the target second coordinates to the projection device.

[0015] The projection device is further configured to correct distortion of the original projection picture based on the target second coordinates.

[0016] In one of the embodiments, the server is further configured to select, for each edge of the reference pattern in the second direction, a target coordinate value in the first direction from the first coordinate of each edge feature point on the edge; the target coordinate value is the coordinate value in the first direction of the first coordinate of each edge feature point on the edge that is closest to the center of the projection picture image; and replace the coordinate value in the first direction of the first coordinate of each edge feature point on the edge with the target coordinate value to obtain the adjusted first coordinate of each edge feature point on the edge.

[0017] In one of the embodiments, the server is further configured to determine the initial second coordinate of each edge feature point of the reference pattern in the projection device coordinate system and the second coordinate of each edge adjacent feature point in the projection device coordinate system; the edge adjacent feature point is a feature point adjacent to the edge feature point in the reference pattern; identify the first coordinate of each edge adjacent feature point in the image coordinate system; determine a first coordinate conversion matrix according to the first coordinate and the second coordinate of each edge adjacent feature point; the first coordinate conversion matrix is a conversion matrix from the projection device coordinate system to the image coordinate system; and convert the initial second coordinate of each edge feature point in the projection device coordinate system to the first coordinate in the image coordinate system according to the first coordinate conversion matrix.

[0018] In one of the embodiments, the server is further configured to determine a second coordinate conversion matrix according to the first coordinate and the second coordinate of each edge adjacent feature point; the second coordinate conversion matrix is a conversion matrix from the image coordinate system to the projection device coordinate system; and convert the adjusted first coordinate of each edge feature point to the coordinate in the projection device coordinate system to obtain the target second coordinate of each edge feature point in the projection device coordinate system according to the second coordinate conversion matrix.

[0019] In one of the embodiments, the reference pattern is a rectangular chessboard; the edge feature point is a corner point of each rectangle on the edge of the rectangular chessboard; the edge adjacent feature point is a corner point of each rectangle in the edge adjacent row and the edge adjacent column of the rectangular chessboard; the edge adjacent row includes the adjacent row of the first row and the last row; and the edge adjacent column includes the adjacent column of the first column and the last column.

[0020] In one of the embodiments, the server is further configured to determine, according to the first coordinates and the second coordinates of at least three corner points of each rectangle in the edge-adjacent row and the edge-adjacent column respectively, a first coordinate conversion matrix corresponding to each rectangle in the edge-adjacent row and the edge-adjacent column respectively; and for each edge feature point, convert the initial second coordinates of the edge feature point in the projection device coordinate system into the first coordinates in the image coordinate system according to the first coordinate conversion matrix corresponding to the rectangle adjacent to the edge feature point.

[0021] In one of the embodiments, the server is further configured to, for each edge feature point, convert the adjusted first coordinates of the edge feature point into coordinates in the projection device coordinate system according to the second coordinate conversion matrix corresponding to the rectangle adjacent to the edge feature point, to obtain the target second coordinates of the edge feature point in the projection device coordinate system.

[0022] In a third aspect, the present application further provides a projection picture distortion correction device. The device comprises

[0023] An edge first coordinate determination module is configured to determine the first coordinates of each edge feature point of a reference pattern in a projection picture image in an image coordinate system; the projection picture image is an image obtained by image acquisition on an original projection picture; the original projection picture is a projection picture obtained by projection of an original reference pattern by a projection device; and the edge feature point is a feature point on an edge of the reference pattern in the projection picture image.

[0024] An edge first coordinate adjustment module is configured to, for each edge of the reference pattern in a first direction, select a target coordinate value in a second direction from the first coordinates of each edge feature point on the edge; the target coordinate value is a coordinate value closest to the center of the projection picture image among the coordinate values of the first coordinates of each edge feature point on the edge in the second direction; the first direction is the direction of one coordinate axis in the image coordinate system; and the second direction is the direction of another coordinate axis in the image coordinate system; and replace the coordinate values in the second direction of the first coordinates of each edge feature point on the edge with the target coordinate value, to obtain the adjusted first coordinates of each edge feature point on the edge.

[0025] A target second coordinate determination module is configured to convert the adjusted first coordinates of each edge feature point into coordinates in a projection device coordinate system, to obtain the target second coordinates of each edge feature point in the projection device coordinate system; and the target second coordinates of each edge feature point are used to make the projection device correct the distortion of the original projection picture based on the target second coordinates.

[0026] In one of the embodiments, the edge first coordinate adjustment module is further configured to: for each edge of the reference pattern in the second direction, select a target coordinate value in the first direction from the first coordinates of the edge feature points on the edge; the target coordinate value is the coordinate value in the first direction of the first coordinates of the edge feature points on the edge that is closest to the center of the projection picture image; replace the coordinate values in the first direction of the first coordinates of the edge feature points on the edge with the target coordinate value to obtain the adjusted first coordinates of the edge feature points on the edge.

[0027] In one of the embodiments, the edge first coordinate determination module is further configured to: determine initial second coordinates of the edge feature points of the reference pattern in the projection picture image in the projection device coordinate system, and second coordinates of edge adjacent feature points in the projection device coordinate system; the edge adjacent feature points are feature points adjacent to the edge feature points in the reference pattern; identify the first coordinates of the edge adjacent feature points in the image coordinate system; determine a first coordinate conversion matrix according to the first coordinates and the second coordinates of the edge adjacent feature points; the first coordinate conversion matrix is a conversion matrix from the projection device coordinate system to the image coordinate system; convert the initial second coordinates of the edge feature points in the projection device coordinate system to the first coordinates in the image coordinate system according to the first coordinate conversion matrix.

[0028] In one of the embodiments, the target second coordinate determination module is further configured to: determine a second coordinate conversion matrix according to the first coordinates and the second coordinates of the edge adjacent feature points; the second coordinate conversion matrix is a conversion matrix from the image coordinate system to the projection device coordinate system; convert the adjusted first coordinates of the edge feature points to coordinates in the projection device coordinate system according to the second coordinate conversion matrix to obtain the target second coordinates of the edge feature points in the projection device coordinate system.

[0029] In one of the embodiments, the reference pattern is a rectangular chessboard; the edge feature points are corner points of each rectangle on the edge of the rectangular chessboard; the edge adjacent feature points are corner points of each rectangle in the edge adjacent rows and the edge adjacent columns of the rectangular chessboard; the edge adjacent rows include adjacent rows of the first row and the last row; the edge adjacent columns include adjacent columns of the first column and the last column.

[0030] In one of the embodiments, the edge first coordinate determination module is further configured to determine, according to the first coordinates and the second coordinates of at least three corner points of each rectangle in the edge adjacent row and the edge adjacent column respectively, a first coordinate conversion matrix corresponding to each rectangle in the edge adjacent row and the edge adjacent column respectively; and convert, for each edge feature point, the initial second coordinate of the edge feature point in the projection device coordinate system into the first coordinate in the image coordinate system according to the first coordinate conversion matrix corresponding to the rectangle adjacent to the edge feature point.

[0031] In one of the embodiments, the target second coordinate determination module is further configured to convert, for each edge feature point, the adjusted first coordinate of the edge feature point into a coordinate in the projection device coordinate system according to the second coordinate conversion matrix corresponding to the rectangle adjacent to the edge feature point, to obtain the target second coordinate of the edge feature point in the projection device coordinate system.

[0032] In a fourth aspect, the present application provides a computer device. The computer device comprises a memory and a processor, and the memory stores a computer program. When the computer program is executed by the processor, the processor performs the steps of the projection picture distortion correction method according to the embodiments of the present application.

[0033] In a fifth aspect, the present application provides a computer readable storage medium. The computer readable storage medium stores a computer program. When the computer program is executed by a processor, the processor performs the steps of the projection picture distortion correction method according to the embodiments of the present application.

[0034] In a sixth aspect, the present application provides a computer program product. The computer program product comprises a computer program. When the computer program is executed by a processor, the processor performs the steps of the projection picture distortion correction method according to the embodiments of the present application.

[0035] The projection picture distortion correction method, system, device, computer device, storage medium and computer program product determine the first coordinates of each edge feature point of the reference pattern in the image coordinate system in the projection picture image, then for each edge of the reference pattern in the first direction, select the target coordinate value in the second direction closest to the center of the projection picture image from the first coordinates of each edge feature point on the edge, replace the coordinate value in the second direction of the first coordinates of each edge feature point on the edge with the target coordinate value, obtain the adjusted first coordinates of each edge feature point on the edge, and then convert the adjusted first coordinates of each edge feature point into coordinates in the projection device coordinate system to obtain the target second coordinates corresponding to each edge feature point, so that the projection device corrects the distortion of the original projection picture based on the target second coordinates, can adjust the deviated edge points in the projection picture to the correct position, and thus realizes the correction of the distortion of the projection picture. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 An application environment diagram of the projection picture distortion correction method in an embodiment;

[0037] Figure 2 A flowchart of the projection picture distortion correction method in an embodiment;

[0038] Figure 3 A reference pattern diagram of a rectangular chessboard in an embodiment;

[0039] Figure 4 A schematic diagram of the projection picture before and after distortion correction in an embodiment;

[0040] Figure 5 A row and column diagram in a rectangular chessboard in an embodiment;

[0041] Figure 6 A principle diagram of perspective transformation in an embodiment;

[0042] Figure 7 A flowchart of device interaction in an embodiment;

[0043] Figure 8 An architecture diagram of the projection picture distortion correction system in an embodiment;

[0044] Figure 9 A structure block diagram of the projection picture distortion correction device in an embodiment;

[0045] Figure 10 An internal structure diagram of the computer device in an embodiment. DETAILED DESCRIPTION

[0046] In order to make the purposes, technical solutions and advantages of the present application clearer, further detailed description will be made to the present application in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0047] In one embodiment, the projection picture distortion correction method provided by the embodiments of the present application can be applied to the application environment as shown in Figure 1 . The projection device 102 can communicate with the control terminal 104 through a network or Bluetooth, etc. The control terminal 104 can communicate with the server 106 through a network. The projection device 102 can project based on the original reference pattern to obtain the original projection picture. The control terminal 104 can collect the image of the projection picture to obtain the projection picture image, and send the projection picture image to the server 106. The server 106 can execute the projection picture distortion correction method in the embodiments of the present application according to the projection picture image to obtain the target second coordinates corresponding to each edge feature point, and send the target second coordinates to the control terminal 104. The control terminal 104 can send the target second coordinates to the projection device. The projection device 102 can correct the distortion of the original projection picture based on the target second coordinates. The projection device 102 can be a projector or other device with projection function. The control terminal 104 can be, but is not limited to, various personal computers, notebook computers, smart phones, tablet computers and portable wearable devices. The portable wearable device can be a smart watch, a smart bracelet, a head-mounted device, etc. The server 106 can be implemented by an independent server or a server cluster composed of multiple servers.

[0048] In other embodiments, the projection picture distortion correction method in the embodiments of the present application can also be executed by the projection device itself without interacting with other devices except the projection device, that is, the projection device projects based on the original reference pattern to obtain the original projection picture, the projection device itself collects the image of the original projection picture to obtain the projection picture image, the projection device itself executes the projection picture distortion correction method in the embodiments of the present application to obtain the target second coordinates, and corrects the distortion of the original projection picture based on the target second coordinates.

[0049] In one embodiment, as shown in Figure 2 , a projection picture distortion correction method is provided. Taking the server 106 in Figure 1 as an example, the method includes the following steps:

[0050] Step 202: Determine the first coordinates of each edge feature point of the reference pattern in the image coordinate system; the projected image is the image obtained by image acquisition of the original projected image; the original projected image is the projected image obtained by the projection device based on the original reference pattern; the edge feature points are the feature points on the edges of the reference pattern in the projected image.

[0051] The original reference pattern is the pattern upon which the projection device bases its projection. The reference pattern is the pattern in the projected image obtained by projecting the original reference pattern and capturing the image of the projected original image. The first coordinate is the coordinate in the image coordinate system. The image coordinate system is a coordinate system established based on the projected image. The original projected image is the image projected onto the projection surface. The projection surface can be any type of surface, such as a wall or a projection screen.

[0052] In one embodiment, the projection device may be an ultra-short-throw projection device.

[0053] In one embodiment, the projection device can project based on the original reference pattern to obtain the original projected image. The control terminal can acquire the image of the original projected image to obtain the projected image. The control terminal can send the projected image to the server, and the server can determine the first coordinates of each edge feature point of the reference pattern in the projected image.

[0054] In one embodiment, the original reference pattern can be any one of a rectangular checkerboard or a circular checkerboard. In one embodiment, the rectangular checkerboard can be a black and white alternating rectangular checkerboard. Figure 3 It is a schematic diagram of a black and white rectangular chessboard.

[0055] In one embodiment, when the original reference pattern is a rectangular checkerboard, the edge points of the reference pattern can be the corner points of each rectangle on the edge side of the rectangular checkerboard in the projected image. In another embodiment, when the original reference pattern is a circular checkerboard, the edge points of the reference pattern can be the centers of each circle on the edge of the circular checkerboard in the projected image.

[0056] In one embodiment, the server can determine the initial second coordinates of each edge feature point of the reference pattern in the projected image, and then convert the initial second coordinates of the edge feature points into first coordinates according to the first coordinate transformation matrix.

[0057] Wherein, the first coordinate conversion matrix is a conversion matrix from the projection device coordinate system to the image coordinate system. The second coordinate is a coordinate in the projection device coordinate system. The projection device coordinate system is a coordinate system established with the projection direction of the light engine in the projection device as the reference. The initial second coordinate is the second coordinate of the edge feature point before distortion correction.

[0058] In step 204, for each edge of the reference pattern in the first direction, a target coordinate value in the second direction is selected from the first coordinates of the edge feature points on the edge; the target coordinate value is the coordinate value in the second direction of the first coordinates of the edge feature points on the edge that is closest to the center of the projection picture image; the first direction is the direction of one coordinate axis in the image coordinate system; and the second direction is the direction of another coordinate axis in the image coordinate system.

[0059] In step 206, the coordinate value in the second direction of the first coordinates of the edge feature points on the edge is replaced by the target coordinate value to obtain the adjusted first coordinates of the edge feature points on the edge.

[0060] In an embodiment, the image coordinate system is a rectangular coordinate system, and the first direction and the second direction are the directions of the horizontal axis and the vertical axis in the image coordinate system, respectively; in the case where the first direction is the direction of the horizontal axis, the second direction is the direction of the vertical axis; and in the case where the first direction is the direction of the vertical axis, the second direction is the direction of the horizontal axis.

[0061] In an embodiment, the server can select, for each edge of the reference pattern in the horizontal axis direction, a target coordinate value in the vertical axis direction (i.e., a target coordinate value in the vertical coordinate) from the first coordinates of the edge feature points on the edge, and then replace the vertical coordinate values in the first coordinates of the edge feature points on the edge by the target coordinate value to obtain the adjusted first coordinates of the edge feature points on the edge in the horizontal axis direction. For each edge of the reference pattern in the vertical axis direction, a target coordinate value in the horizontal axis direction (i.e., a target coordinate value in the horizontal coordinate) is selected from the first coordinates of the edge feature points on the edge, and then the horizontal coordinate values in the first coordinates of the edge feature points on the edge are replaced by the target coordinate value to obtain the adjusted first coordinates of the edge feature points on the edge in the vertical axis direction.

[0062] For example, the image coordinate system is established with the upper left corner of the projected picture image as the origin, the vertically downward direction as the positive direction of the vertical axis, and the horizontally right direction as the positive direction of the horizontal axis. The server can select the maximum vertical coordinate value from the first coordinates of each edge feature point on the upper edge in the horizontal direction as the target vertical coordinate value, and then replace the vertical coordinate values in the first coordinates of each edge feature point on the edge with the target vertical coordinate value, to obtain the adjusted first coordinates of each edge feature point on each edge in the horizontal direction. The server can select the minimum vertical coordinate value from the first coordinates of each edge feature point on the lower edge in the horizontal direction as the target vertical coordinate value, and then replace the vertical coordinate values in the first coordinates of each edge feature point on the edge with the target vertical coordinate value, to obtain the adjusted first coordinates of each edge feature point on each edge in the horizontal direction. The server can select the maximum horizontal coordinate value from the first coordinates of each edge feature point on the left edge in the vertical direction as the target horizontal coordinate value, and then replace the horizontal coordinate values in the first coordinates of each edge feature point on the edge with the target horizontal coordinate value, to obtain the adjusted first coordinates of each edge feature point on each edge in the vertical direction. The server can select the minimum horizontal coordinate value from the first coordinates of each edge feature point on the right edge in the vertical direction as the target horizontal coordinate value, and then replace the horizontal coordinate values in the first coordinates of each edge feature point on the edge with the target horizontal coordinate value, to obtain the adjusted first coordinates of each edge feature point on each edge in the vertical direction.

[0063] In step 208, the server converts the adjusted first coordinates of each edge feature point into coordinates in the projection device coordinate system, to obtain target second coordinates of each edge feature point in the projection device coordinate system; and the target second coordinates of each edge feature point are used to enable the projection device to correct the distortion of the original projected picture based on the target second coordinates.

[0064] In step 208, the server converts the adjusted first coordinates of each edge feature point into coordinates in the projection device coordinate system, to obtain target second coordinates of each edge feature point in the projection device coordinate system; and the target second coordinates of each edge feature point are used to enable the projection device to correct the distortion of the original projected picture based on the target second coordinates.

[0065] In one embodiment, the server can convert the adjusted first coordinates of each edge feature point into coordinates in the projection device coordinate system, to obtain target second coordinates corresponding to each edge feature point, and then send the target second coordinates to the control terminal. The control terminal can send the target second coordinates to the projection device, and the projection device can correct the distortion of the original projected picture based on the target second coordinates.

[0066] In one embodiment, the server can convert the adjusted first coordinates of each edge feature point into second coordinates in the projection device coordinate system according to the second coordinate conversion matrix from the image coordinate system to the projection device coordinate system, to obtain target second coordinates corresponding to each edge feature point.

[0067] In one embodiment, the projection device can perform multi-point correction based on the target second coordinates to correct distortion of the original projected image. In another embodiment, the projection device can invoke a multi-point keystone correction interface to perform multi-point correction based on the target second coordinates to correct distortion of the original projected image. In yet another embodiment, the projection device can invoke a multi-point keystone correction interface to cause the optical engine to project according to the target second coordinates to correct distortion of the original projected image projected by the optical engine.

[0068] like Figure 4 As shown, there is obvious distortion in the original projected image before distortion correction. After distortion correction, the distortion in the projected image is corrected.

[0069] The above-described projection distortion correction method determines the first coordinates of each edge feature point of the reference pattern in the projection image in the image coordinate system. Then, for each edge of the reference pattern in the first direction, it selects the target coordinate value closest to the center of the projection image in the second direction from the first coordinates of each edge feature point on the edge. The coordinate values ​​in the second direction of each edge feature point are then replaced with the target coordinate values ​​to obtain the adjusted first coordinates of each edge feature point. The adjusted first coordinates of each edge feature point are then converted to coordinates in the projection device coordinate system to obtain the target second coordinates corresponding to each edge feature point. This allows the projection device to correct the distortion of the original projection image based on the target second coordinates, adjusting the deviated edge points in the projection image to the correct position, thereby achieving the correction of projection image distortion. This method can efficiently and accurately correct the distortion of the projection image, improving the efficiency and accuracy of projection image distortion correction.

[0070] In one embodiment, before converting the adjusted first coordinates of each edge feature point into coordinates in the projection device coordinate system to obtain the target second coordinates of each edge feature point in the projection device coordinate system, the method further includes: for each edge of the reference pattern in the second direction, selecting a target coordinate value in the first direction from the first coordinates of each edge feature point on the edge; the target coordinate value is the coordinate value of the first coordinate of each edge feature point on the edge that is closest to the center of the projected image in the first direction; replacing the coordinate value in the first direction of each edge feature point on the edge with the target coordinate value to obtain the adjusted first coordinates of each edge feature point on the edge.

[0071] In the above embodiments, the first coordinates of each edge not only in the first direction but also in the second direction are adjusted to accurately correct distortion.

[0072] In one embodiment, determining the first coordinates of the edge feature points of the reference pattern in the projection picture image in the image coordinate system comprises: determining initial second coordinates of the edge feature points of the reference pattern in the projection picture image in the projection device coordinate system, and second coordinates of the edge adjacent feature points in the projection device coordinate system; the edge adjacent feature point is a feature point adjacent to the edge feature point in the reference pattern; identifying the first coordinates of the edge adjacent feature points in the image coordinate system; determining a first coordinate conversion matrix according to the first coordinates and the second coordinates of the edge adjacent feature points; the first coordinate conversion matrix is a conversion matrix from the projection device coordinate system to the image coordinate system; and converting the initial second coordinates of the edge feature points in the projection device coordinate system to the first coordinates in the image coordinate system according to the first coordinate conversion matrix.

[0073] In one embodiment, the server can calculate the initial second coordinates of the edge feature points of the reference pattern in the projection picture image and the second coordinates of the edge adjacent feature points according to the size of the original reference pattern.

[0074] For example: Figure 5 The original reference pattern in the image is a rectangular chessboard, and the size of the rectangular chessboard image projected by the light machine is 48 pixels*40=1920 pixels in length and 54 pixels*20=1080 pixels in width, and a total of 40*20 rectangles are included, each with a length of 48 pixels and a width of 54 pixels. Then Figure 5 The initial second coordinates of the edge feature point A of the reference pattern in the image are (0, 0), the initial second coordinates of the edge feature point B are (1920, 0), the initial second coordinates of the edge feature point C are (0, 1080), and the initial second coordinates of the edge feature point D are (1920, 1080).

[0075] In one embodiment, in the case of a rectangular chessboard, the server can call the findChessboardCorners function in opencv (computer vision software library) to identify the first coordinates of each corner point in the rectangular chessboard other than the edge feature point, to obtain the first coordinates of the edge adjacent feature points.

[0076] In one embodiment, the server can perform perspective transformation according to the first coordinates and the second coordinates of the edge adjacent feature points to determine the first coordinate conversion matrix. In one embodiment, the server can call the getPerspectiveTransform function in opencv to perform perspective transformation according to the first coordinates and the second coordinates of the edge adjacent feature points to determine the first coordinate conversion matrix.

[0077] The principle of perspective transformation using the getPerspectiveTransform function is as follows: perspective transformation is to map a projection point in a plane to a new view plane, as shown in Figure 6 ABC is converted to A'B'C' by perspective transformation, ABC is in the same plane coordinate system, and A'B'C' is in another plane coordinate system. Assuming that [x', y', w'] is the coordinate after transformation (i.e., the coordinate of A'B'C'), and [u, v, w] is the coordinate before transformation (i.e., the coordinate of ABC). The formula of perspective transformation is as follows:

[0078]

[0079] wherein, is the perspective transformation matrix, i.e., the coordinate conversion matrix.

[0080] In an embodiment, the server can convert the initial second coordinate of the edge feature point into the first coordinate according to the first coordinate conversion matrix. In an embodiment, the server can multiply the initial second coordinate of the edge feature point by the first coordinate conversion matrix to obtain the first coordinate of the edge feature point.

[0081] In the above embodiment, by identifying the first coordinates of the edge adjacent feature points, and then determining the first coordinate conversion matrix according to the first coordinates and the second coordinates of the edge adjacent feature points, and converting the initial second coordinate of the edge feature point into the first coordinate according to the first coordinate conversion matrix, the first coordinate of the edge feature point can be efficiently and accurately determined, the efficiency and accuracy of the projection picture distortion correction are improved, and the problem that the first coordinate of the edge feature point is difficult to determine is solved.

[0082] In an embodiment, the method further comprises: determining a second coordinate conversion matrix according to the first coordinates and the second coordinates of the edge adjacent feature points; the second coordinate conversion matrix is a conversion matrix from the image coordinate system to the projection device coordinate system; and converting the adjusted first coordinates of the edge feature points into coordinates in the projection device coordinate system to obtain target second coordinates of the edge feature points in the projection device coordinate system comprises: converting the adjusted first coordinates of the edge feature points into coordinates in the projection device coordinate system according to the second coordinate conversion matrix to obtain target second coordinates of the edge feature points in the projection device coordinate system.

[0083] In an embodiment, the server can perform perspective transformation according to the first coordinates and the second coordinates of the edge adjacent feature points to determine the second coordinate conversion matrix. In an embodiment, the server can call the getPerspectiveTransform function in opencv to perform perspective transformation according to the first coordinates and the second coordinates of the edge adjacent feature points to determine the second coordinate conversion matrix.

[0084] In one embodiment, the server can multiply the adjusted first coordinates of the edge feature points by the second coordinate conversion matrix to obtain the target second coordinates of the edge feature points in the projection device coordinate system. In the above embodiment, the second coordinate conversion matrix is determined according to the first coordinates and the second coordinates of the edge adjacent feature points, and then the adjusted first coordinates of the edge feature points are converted into coordinates in the projection device coordinate system according to the second coordinate conversion matrix to obtain the target second coordinates of the edge feature points in the projection device coordinate system, so that the target second coordinates can be efficiently and accurately obtained.

[0085] In one embodiment, the reference pattern is a rectangular checkerboard, the edge feature points are corner points of each rectangle at the edge of the rectangular checkerboard, and the edge adjacent feature points are corner points of each rectangle in the edge adjacent row and the edge adjacent column of the rectangular checkerboard. The edge adjacent row includes adjacent rows of the first row and the last row, and the edge adjacent column includes adjacent columns of the first column and the last column.

[0086] In one embodiment, the reference pattern is a rectangular checkerboard, the edge feature points are corner points of each rectangle at the edge of the rectangular checkerboard, and the edge adjacent feature points are corner points of each rectangle in the edge adjacent row and the edge adjacent column of the rectangular checkerboard. The edge adjacent row includes adjacent rows of the first row and the last row, and the edge adjacent column includes adjacent columns of the first column and the last column.

[0087] For example, as shown in the rectangular checkerboard shown in Figure 5 which contains 40*20 rectangles, the edge feature points include 40 corner points of each rectangle in the first row and the 20th row of the rectangular checkerboard, and 20 corner points of each rectangle in the first column and the 40th column of the rectangular checkerboard. The edge adjacent feature points include 38 corner points of the rectangles between the second row and the 19th row, and 18 corner points of the rectangles between the second column and the 39th column.

[0088] In the above embodiment, the rectangular checkerboard is used as the reference pattern, the edge feature points are corner points of each rectangle at the edge of the rectangular checkerboard, and the edge adjacent feature points are corner points of each rectangle in the edge adjacent row and the edge adjacent column of the rectangular checkerboard, so that the first coordinate conversion matrix can be efficiently and accurately determined according to the first coordinates and the second coordinates of the edge adjacent feature points, and then the first coordinates of the edge feature points can be efficiently and accurately determined according to the first coordinate conversion matrix.

[0089] In one embodiment, determining the first coordinate conversion matrix according to the first coordinates and the second coordinates of the edge-adjacent feature points comprises: determining, according to the first coordinates and the second coordinates of at least three corner points of each rectangle in the edge-adjacent row and the edge-adjacent column respectively, a first coordinate conversion matrix corresponding to each rectangle in the edge-adjacent row and the edge-adjacent column respectively; and converting, according to the first coordinate conversion matrix, the initial second coordinates of the edge feature points in the projection device coordinate system into the first coordinates in the image coordinate system comprises: for each edge feature point, converting, according to the first coordinate conversion matrix corresponding to the rectangle adjacent to the edge feature point, the initial second coordinates of the edge feature point in the projection device coordinate system into the first coordinates in the image coordinate system.

[0090] In one embodiment, the server can determine the first coordinate conversion matrix corresponding to each rectangle in the edge-adjacent row and the edge-adjacent column respectively according to the first coordinates and the second coordinates of 3 or 4 corner points of each rectangle in the edge-adjacent row and the edge-adjacent column. In one embodiment, the server can convert, for each edge feature point, the initial second coordinates of the edge feature point into the first coordinates according to the first coordinate conversion matrix corresponding to the rectangle adjacent to the edge feature point. In one embodiment, the server can multiply, for each edge feature point, the initial second coordinates of the edge feature point by the first coordinate conversion matrix corresponding to the rectangle adjacent to the edge feature point to obtain the first coordinates of the edge feature point.

[0091] In the above embodiment, the first coordinate conversion matrix corresponding to each rectangle in the edge-adjacent row and the edge-adjacent column respectively is calculated more carefully, and then for each edge feature point, the initial second coordinates of the edge feature point are converted into the first coordinates according to the first coordinate conversion matrix corresponding to the rectangle adjacent to the edge feature point, which can use a more accurate first coordinate conversion matrix to calculate the first coordinates for the edge feature points at different positions, thereby improving the accuracy of the first coordinates of the edge feature points and further improving the accuracy of the projection picture distortion correction.

[0092] In one embodiment, converting the adjusted first coordinates of each edge feature point into coordinates in the projection device coordinate system to obtain the target second coordinates of each edge feature point in the projection device coordinate system comprises: for each edge feature point, converting the adjusted first coordinates of the edge feature point into coordinates in the projection device coordinate system according to the second coordinate conversion matrix corresponding to the rectangle adjacent to the edge feature point to obtain the target second coordinates of the edge feature point in the projection device coordinate system.

[0093] In one embodiment, the server can determine the second coordinate conversion matrix corresponding to each rectangle in the edge-adjacent row and the edge-adjacent column respectively according to the first coordinates and the second coordinates of 3 or 4 corner points of each rectangle in the edge-adjacent row and the edge-adjacent column.

[0094] In an embodiment, the server can convert the adjusted first coordinates of each edge feature point into second coordinates according to a second coordinate conversion matrix corresponding to the rectangle adjacent to the edge feature point, to obtain the target second coordinates corresponding to the edge feature point.

[0095] In an embodiment, the server can multiply the adjusted first coordinates of each edge feature point by a second coordinate conversion matrix corresponding to the rectangle adjacent to the edge feature point, to obtain the target second coordinates corresponding to the edge feature point.

[0096] In the above embodiments, for each edge feature point, a more corresponding and accurate second coordinate conversion matrix is used to convert the adjusted first coordinates of the edge feature point into second coordinates, to obtain the target second coordinates corresponding to the edge feature point, which can obtain more accurate target second coordinates, and further improve the accuracy of the projection picture distortion correction.

[0097] In an embodiment, the method further includes: the projection device projects based on the original reference pattern to obtain an original projection picture; the control terminal performs image acquisition on the original projection picture to obtain a projection picture image; the server performs the steps of determining the first coordinates of each edge feature point of the reference pattern in the projection picture image in an image coordinate system and subsequent steps, to obtain the target second coordinates of each edge feature point in the projection device coordinate system; the control terminal obtains the target second coordinates from the server and sends them to the projection device; and the projection device corrects the distortion of the original projection picture based on the target second coordinates.

[0098] In an embodiment, the control terminal can perform image acquisition on the original projection picture based on an application tool in the control terminal to obtain a projection picture image, and send the projection picture image to the server. In an embodiment, the application tool can be any one of a mini-program or an application (app).

[0099] In an embodiment, the control terminal can send a projection instruction to the projection device, and the projection device can project based on the original reference pattern in response to the projection instruction to project an original projection picture containing the reference pattern. In an embodiment, the control terminal can send the projection instruction to the projection device based on an application tool in the control terminal.

[0100] In an embodiment, the projection device can pre-store an image of the original reference pattern, and after receiving the projection instruction, project based on the image of the original reference pattern in response to the projection instruction to project an original projection picture containing the reference pattern.

[0101] As Figure 7As shown, the overall flow diagram shows the interaction of each device, the control terminal is in communication connection with the projection device, the projection device projects the original projection picture, the control terminal collects the image of the original projection picture, obtains the projection picture image, and then uploads the projection picture image to the server, the server determines the target second coordinate according to the projection picture image, and sends the target second coordinate to the control terminal, the control terminal sends the target second coordinate to the projection device, and the projection device calls the multi-point trapezoidal correction interface based on the target second coordinate to correct the distortion of the original projection picture.

[0102] In the above embodiment, the server is used to perform the projection picture distortion correction method, which reduces the power consumption of the projection device, and the control terminal is used for intermediate control, which improves the convenience of use.

[0103] It should be understood that, although each step in the flowchart involved in the above embodiments is displayed in sequence according to the arrow, these steps are not necessarily executed in the order indicated by the arrow. Unless otherwise stated herein, the execution of these steps has no strict order limitation, and these steps can be executed in other orders. Moreover, at least part of the steps in the flowchart involved in the above embodiments can include multiple steps or stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily sequential, but can be alternately executed with at least part of other steps or steps or stages in other steps.

[0104] Based on the same inventive concept, the embodiments of the present application also provide a projection picture distortion correction system for implementing the above-mentioned projection picture distortion correction method. The problem-solving implementation scheme provided by the system is similar to the implementation scheme described in the above method, so the specific limitations in one or more projection picture distortion correction system embodiments provided below can refer to the limitations of the projection picture distortion correction method in the above text, which will not be repeated here.

[0105] In one embodiment, as shown in Figure 8 A projection picture distortion correction system 800 is provided, comprising a projection device 802, a control terminal 804 and a server 806, wherein:

[0106] The projection device 802 is configured to project based on the original reference pattern to obtain the original projection picture.

[0107] The control terminal 804 is configured to collect the image of the original projection picture to obtain the projection picture image.

[0108] Server 806 is used to determine the first coordinates of each edge feature point of the reference pattern in the projected image in the image coordinate system; for each edge of the reference pattern in the first direction, a target coordinate value in the second direction is selected from the first coordinates of each edge feature point on the edge; the coordinate values ​​in the second direction of the first coordinates of each edge feature point on the edge are replaced with the target coordinate values ​​to obtain the adjusted first coordinates of each edge feature point on the edge; the adjusted first coordinates of each edge feature point are converted into coordinates in the projection device coordinate system to obtain the target second coordinates of each edge feature point in the projection device coordinate system; the edge feature point is a feature point on the edge of the reference pattern in the projected image; the target coordinate value is the coordinate value of the first coordinate of each edge feature point on the edge that is closest to the center of the projected image in the second direction; the first direction is the direction of one coordinate axis in the image coordinate system; the second direction is the direction of another coordinate axis in the image coordinate system.

[0109] The control terminal 804 is also used to obtain the target second coordinates of each edge feature point from the server and send the target second coordinates to the projection device.

[0110] The projection device 802 is also used to correct distortion of the original projected image based on the second coordinate of the target.

[0111] In one embodiment, the server 806 is further configured to select, for each edge of the reference pattern in the second direction, a target coordinate value in the first direction from the first coordinates of each edge feature point on the edge; the target coordinate value is the coordinate value of the first coordinate of each edge feature point on the edge that is closest to the center of the projected image in the first direction; and replace the coordinate value in the first direction of each edge feature point on the edge with the target coordinate value to obtain the adjusted first coordinates of each edge feature point on the edge.

[0112] In one embodiment, server 806 is further configured to determine the initial second coordinates of each edge feature point of the reference pattern in the projected image in the projection device coordinate system, and the second coordinates of each edge neighbor feature point in the projection device coordinate system; the edge neighbor feature point is a feature point in the reference pattern that is adjacent to the edge feature point; identify the first coordinates of each edge neighbor feature point in the image coordinate system; determine a first coordinate transformation matrix based on the first and second coordinates of the edge neighbor feature points; the first coordinate transformation matrix is ​​a transformation matrix from the projection device coordinate system to the image coordinate system; and convert the initial second coordinates of the edge feature points in the projection device coordinate system to the first coordinates in the image coordinate system based on the first coordinate transformation matrix.

[0113] In one embodiment, the server 806 is further configured to determine a second coordinate transformation matrix based on the first and second coordinates of the edge neighboring feature points; the second coordinate transformation matrix is ​​a transformation matrix from the image coordinate system to the projection device coordinate system; based on the second coordinate transformation matrix, the adjusted first coordinates of each edge feature point are converted into coordinates in the projection device coordinate system to obtain the target second coordinates of each edge feature point in the projection device coordinate system.

[0114] In one embodiment, the reference pattern is a rectangular checkerboard; edge feature points are the corner points of each rectangle at the edge of the rectangular checkerboard; edge neighbor feature points are the corner points of each rectangle in the edge adjacent row and edge adjacent column of the rectangular checkerboard; edge adjacent row includes adjacent rows of the first row and the last row; edge adjacent column includes adjacent columns of the first column and the last column.

[0115] In one embodiment, the server 806 is further configured to determine the first coordinate transformation matrix corresponding to each rectangle in the edge-adjacent row and edge-adjacent column based on the first coordinates and the second coordinates of at least three corner points of each rectangle in the edge-adjacent row and edge-adjacent column, respectively; and for each edge feature point, convert the initial second coordinates of the edge feature point in the projection device coordinate system into the first coordinates in the image coordinate system based on the first coordinate transformation matrix corresponding to the rectangle adjacent to the edge feature point.

[0116] In one embodiment, the server 806 is further configured to, for each edge feature point, convert the adjusted first coordinates of the edge feature point into coordinates in the projection device coordinate system according to the second coordinate transformation matrix corresponding to the rectangle adjacent to the edge feature point, thereby obtaining the target second coordinates of the edge feature point in the projection device coordinate system.

[0117] The aforementioned projection distortion correction system determines the first coordinates of each edge feature point of the reference pattern in the projection image in the image coordinate system. Then, for each edge of the reference pattern in the first direction, it selects the target coordinate value closest to the center of the projection image in the second direction from the first coordinates of each edge feature point on the edge. The first coordinates of each edge feature point in the second direction are then replaced with the target coordinate value to obtain the adjusted first coordinates of each edge feature point. Finally, the adjusted first coordinates of each edge feature point are converted to coordinates in the projection device coordinate system to obtain the target second coordinates corresponding to each edge feature point. This allows the projection device to correct the distortion of the original projection image based on the target second coordinates, adjusting the deviated edge points in the projection image to the correct position, thereby achieving distortion correction of the projection image. This system can efficiently and accurately correct the distortion of the projection image, improving the efficiency and accuracy of projection distortion correction.

[0118] Based on the same inventive concept, this application also provides a projection image distortion correction device for implementing the projection image distortion correction method described above. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations of one or more projection image distortion correction device embodiments provided below can be found in the limitations of the projection image distortion correction method described above, and will not be repeated here.

[0119] In one embodiment, such as Figure 9 As shown, a projection image distortion correction device 900 is provided, including: an edge first coordinate determination module 902, an edge first coordinate adjustment module 904, and a target second coordinate determination module 906, wherein:

[0120] The edge first coordinate determination module 902 is used to determine the first coordinates of each edge feature point of the reference pattern in the projected image in the image coordinate system; the projected image is the image obtained by image acquisition of the original projected image; the original projected image is the projected image obtained by the projection device based on the original reference pattern; the edge feature points are the feature points on the edge of the reference pattern in the projected image.

[0121] The edge first coordinate adjustment module 904 is used to select target coordinate values ​​in the second direction from the first coordinates of each edge feature point on the edge for each edge of the reference pattern in the first direction; the target coordinate value is the coordinate value of the first coordinate of each edge feature point on the edge that is closest to the center of the projected image in the second direction; the first direction is the direction of one coordinate axis in the image coordinate system; the second direction is the direction of another coordinate axis in the image coordinate system; the first coordinate of each edge feature point on the edge is replaced with the target coordinate value in the second direction to obtain the adjusted first coordinates of each edge feature point on the edge.

[0122] The target second coordinate determination module 906 is used to convert the adjusted first coordinates of each edge feature point into coordinates in the projection device coordinate system to obtain the target second coordinates of each edge feature point in the projection device coordinate system; the target second coordinates of each edge feature point are used to enable the projection device to correct the distortion of the original projection image based on the target second coordinates.

[0123] In one embodiment, the edge first coordinate adjustment module 904 is further configured to select a target coordinate value in the first direction from the first coordinates of each edge feature point on the edge for each edge of the reference pattern in the second direction; the target coordinate value is the coordinate value of the first coordinate of each edge feature point on the edge that is closest to the center of the projected image in the first direction; and replace the coordinate value in the first direction of each edge feature point on the edge with the target coordinate value to obtain the adjusted first coordinates of each edge feature point on the edge.

[0124] In one embodiment, the edge first coordinate determination module 902 is further configured to determine the initial second coordinates of each edge feature point of the reference pattern in the projected image in the projection device coordinate system, and the second coordinates of each edge neighbor feature point in the projection device coordinate system; the edge neighbor feature point is a feature point in the reference pattern that is adjacent to the edge feature point; identify the first coordinates of each edge neighbor feature point in the image coordinate system; determine a first coordinate transformation matrix based on the first and second coordinates of the edge neighbor feature points; the first coordinate transformation matrix is ​​a transformation matrix from the projection device coordinate system to the image coordinate system; and convert the initial second coordinates of the edge feature points in the projection device coordinate system to the first coordinates in the image coordinate system based on the first coordinate transformation matrix.

[0125] In one embodiment, the target second coordinate determination module 906 is further configured to determine a second coordinate transformation matrix based on the first and second coordinates of the edge neighboring feature points; the second coordinate transformation matrix is ​​a transformation matrix from the image coordinate system to the projection device coordinate system; based on the second coordinate transformation matrix, the adjusted first coordinates of each edge feature point are converted into coordinates in the projection device coordinate system to obtain the target second coordinates of each edge feature point in the projection device coordinate system.

[0126] In one embodiment, the reference pattern is a rectangular checkerboard; edge feature points are the corner points of each rectangle at the edge of the rectangular checkerboard; edge neighbor feature points are the corner points of each rectangle in the edge adjacent row and edge adjacent column of the rectangular checkerboard; edge adjacent row includes adjacent rows of the first row and the last row; edge adjacent column includes adjacent columns of the first column and the last column.

[0127] In one embodiment, the edge first coordinate determination module 902 is further configured to determine the first coordinate transformation matrix corresponding to each rectangle in the edge adjacent row and edge adjacent column based on the first coordinate and second coordinate of at least three corner points of each rectangle in the edge adjacent row and edge adjacent column respectively; and for each edge feature point, convert the initial second coordinate of the edge feature point in the projection device coordinate system into the first coordinate in the image coordinate system based on the first coordinate transformation matrix corresponding to the rectangle adjacent to the edge feature point.

[0128] In one embodiment, the target second coordinate determination module 906 is further configured to, for each edge feature point, convert the adjusted first coordinate of the edge feature point into coordinates in the projection device coordinate system according to the second coordinate transformation matrix corresponding to the rectangle adjacent to the edge feature point, so as to obtain the target second coordinate corresponding to the edge feature point.

[0129] The aforementioned projection image distortion correction device determines the first coordinates of each edge feature point of the reference pattern in the projection image in the image coordinate system. Then, for each edge of the reference pattern in the first direction, it selects the target coordinate value closest to the center of the projection image in the second direction from the first coordinates of each edge feature point on the edge. It then replaces the coordinate value in the second direction of the first coordinates of each edge feature point with the target coordinate value to obtain the adjusted first coordinates of each edge feature point. Finally, it converts the adjusted first coordinates of each edge feature point into coordinates in the projection device coordinate system to obtain the target second coordinates corresponding to each edge feature point. This allows the projection device to correct the distortion of the original projection image based on the target second coordinates, adjusting the deviated edge points in the projection image to the correct position, thereby realizing the correction of projection image distortion. It can efficiently and accurately correct the distortion of the projection image, improving the efficiency and accuracy of projection image distortion correction.

[0130] Each module in the aforementioned projection distortion correction device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the computer device's memory as software, so that the processor can call and execute the corresponding operations of each module.

[0131] In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 10 As shown, the computer device includes a processor, memory, and a network interface connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The database stores data. The network interface communicates with external terminals via a network connection. When executed by the processor, the computer program implements a projection distortion correction method.

[0132] Those skilled in the art will understand that Figure 10The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0133] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above-described method embodiments.

[0134] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon that, when executed by a processor, implements the steps in the above method embodiments.

[0135] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above method embodiments.

[0136] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties.

[0137] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0138] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0139] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method for correcting projection image distortion, characterized in that, The method includes: The initial second coordinates of each edge feature point of the reference pattern in the projected image are determined in the projection device coordinate system, as well as the second coordinates of each edge-adjacent feature point in the projection device coordinate system. The edge-adjacent feature point is a feature point in the reference pattern that is adjacent to the edge feature point. The reference pattern is a rectangular checkerboard. The edge feature point is the corner point of each rectangle at the edge of the rectangular checkerboard. Each rectangle at the edge refers to the rectangle in the first and last rows, and the first and last columns of the rectangular checkerboard. The edge-adjacent feature point is the corner point of each rectangle in the adjacent rows and adjacent columns of the rectangular checkerboard. The adjacent rows include adjacent rows of the first and last rows; the adjacent columns include adjacent columns of the first and last columns. Identify the first coordinates of each of the edge-adjacent feature points in the image coordinate system; A first coordinate transformation matrix is ​​determined based on the first and second coordinates of the feature points adjacent to the edge; the first coordinate transformation matrix is ​​a transformation matrix from the projection device coordinate system to the image coordinate system. According to the first coordinate transformation matrix, the initial second coordinates of the edge feature points in the projection device coordinate system are transformed into first coordinates in the image coordinate system; the projected image is an image obtained by image acquisition of the original projected image; the original projected image is a projected image obtained by the projection device based on the original reference pattern; the edge feature points are feature points on the edges of the reference pattern in the projected image. For each edge of the reference pattern in the first direction, a target coordinate value in the second direction is selected from the first coordinates of each edge feature point on the edge; the target coordinate value is the coordinate value of the first coordinate of each edge feature point on the edge that is closest to the center of the projected image in the second direction; the first direction is the direction of one coordinate axis in the image coordinate system; the second direction is the direction of another coordinate axis in the image coordinate system. Replace the coordinate values ​​in the second direction of the first coordinates of each edge feature point on the edge with the target coordinate values ​​to obtain the adjusted first coordinates of each edge feature point on the edge; The adjusted first coordinates of each edge feature point are converted into coordinates in the projection device coordinate system to obtain the target second coordinates of each edge feature point in the projection device coordinate system; the target second coordinates of each edge feature point are used to enable the projection device to correct the distortion of the original projected image based on the target second coordinates.

2. The method according to claim 1, characterized in that, Before converting the adjusted first coordinates of each edge feature point into coordinates in the projection device coordinate system to obtain the target second coordinates of each edge feature point in the projection device coordinate system, the method further includes: For each edge of the reference pattern in the second direction, a target coordinate value in the first direction is selected from the first coordinates of each edge feature point on the edge; the target coordinate value is the coordinate value of the first coordinate of each edge feature point on the edge that is closest to the center of the projected image in the first direction. The first coordinates of each edge feature point on the edge are replaced with the target coordinates in the first direction to obtain the adjusted first coordinates of each edge feature point on the edge.

3. The method according to claim 1, characterized in that, The method further includes: A second coordinate transformation matrix is ​​determined based on the first and second coordinates of the feature points adjacent to the edge; the second coordinate transformation matrix is ​​a transformation matrix from the image coordinate system to the projection device coordinate system. The step of converting the adjusted first coordinates of each edge feature point into coordinates in the projection device coordinate system to obtain the target second coordinates of each edge feature point in the projection device coordinate system includes: Based on the second coordinate transformation matrix, the adjusted first coordinates of each edge feature point are converted into coordinates in the projection device coordinate system to obtain the target second coordinates of each edge feature point in the projection device coordinate system.

4. The method according to claim 1, characterized in that, Determining the first coordinate transformation matrix based on the first and second coordinates of the feature points adjacent to the edge includes: Based on the first and second coordinates of at least three corner points of each rectangle in the adjacent row and column of the edge, determine the first coordinate transformation matrix corresponding to each rectangle in the adjacent row and column of the edge, respectively; The step of converting the initial second coordinates of the edge feature points in the projection device coordinate system to the first coordinates in the image coordinate system according to the first coordinate transformation matrix includes: For each edge feature point, the initial second coordinates of the edge feature point in the projection device coordinate system are converted into first coordinates in the image coordinate system according to the first coordinate transformation matrix corresponding to the rectangle adjacent to the edge feature point.

5. The method according to claim 4, characterized in that, The step of converting the adjusted first coordinates of each edge feature point into coordinates in the projection device coordinate system to obtain the target second coordinates of each edge feature point in the projection device coordinate system includes: For each edge feature point, the adjusted first coordinates of the edge feature point are converted into coordinates in the projection device coordinate system according to the second coordinate transformation matrix corresponding to the rectangle adjacent to the edge feature point, so as to obtain the target second coordinates of the edge feature point in the projection device coordinate system.

6. The method according to any one of claims 1 to 5, characterized in that, The method further includes: The projection device projects the original image based on the original reference pattern; The control terminal acquires images from the original projected image to obtain the projected image. The server executes the first coordinates of each edge feature point of the reference pattern in the projected image in the image coordinate system and subsequent steps to obtain the target second coordinates of each edge feature point in the projection device coordinate system. The control terminal obtains the second coordinates of the target from the server and sends them to the projection device; The projection device corrects the distortion of the original projected image based on the second coordinate of the target.

7. A projection image distortion correction system, characterized in that, The system includes a projection device, a control terminal, and a server, wherein: The projection device is used to project an original reference pattern to obtain an original projected image. The control terminal is used to acquire images from the original projection screen to obtain a projection screen image; The server is configured to determine the initial second coordinates of each edge feature point of the reference pattern in the projected image in the projection device coordinate system, and the second coordinates of each adjacent edge feature point in the projection device coordinate system; the adjacent edge feature point is a feature point in the reference pattern that is adjacent to the edge feature point; the reference pattern is a rectangular checkerboard; the edge feature point is the corner point of each rectangle at the edge of the rectangular checkerboard; each rectangle at the edge refers to the rectangle in the first row and last row, and the first column and last column of the rectangular checkerboard; the adjacent edge feature point is the corner point of each rectangle in the adjacent row and adjacent column of the rectangular checkerboard; the adjacent row includes the adjacent row of the first row and the last row; the adjacent column includes the adjacent column of the first column and the last column; identify the first coordinates of each adjacent edge feature point in the image coordinate system; determine a first coordinate transformation matrix based on the first and second coordinates of the adjacent edge feature points; the first coordinate transformation matrix is ​​a transformation matrix from the projection device coordinate system to the image coordinate system; and determine the first coordinate transformation matrix based on the first and second coordinates of the adjacent edge feature points. A coordinate transformation matrix is ​​used to convert the initial second coordinates of the edge feature points in the projection device coordinate system into first coordinates in the image coordinate system. For each edge of the reference pattern in the first direction, a target coordinate value in the second direction is selected from the first coordinates of each edge feature point on the edge. The coordinate values ​​in the second direction of the first coordinates of each edge feature point on the edge are replaced with the target coordinate values ​​to obtain the adjusted first coordinates of each edge feature point on the edge. The adjusted first coordinates of each edge feature point are converted into coordinates in the projection device coordinate system to obtain the target second coordinates of each edge feature point in the projection device coordinate system. The edge feature points are feature points on the edges of the reference pattern in the projected image. The target coordinate value is the coordinate value of the first coordinates of each edge feature point on the edge that is closest to the center of the projected image in the second direction. The first direction is the direction of one coordinate axis in the image coordinate system. The second direction is the direction of another coordinate axis in the image coordinate system. The control terminal is further configured to obtain the target second coordinates of each of the edge feature points from the server and send the target second coordinates to the projection device; The projection device is also used to correct distortion of the original projected image based on the second coordinates of the target.

8. The system according to claim 7, characterized in that, The server is also used for: For each edge of the reference pattern in the second direction, a target coordinate value in the first direction is selected from the first coordinates of each edge feature point on the edge. The target coordinate value is the coordinate value of the first coordinate of each edge feature point on the edge in the first direction that is closest to the center of the projected image. The first coordinates of each edge feature point on the edge are replaced with the target coordinates in the first direction to obtain the adjusted first coordinates of each edge feature point on the edge.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

Images