Optical machine off-axis proportion measuring method and device and projection equipment

Abstract

The invention relates to a light machine off-axis proportion measuring method and device and projection equipment. The method comprises the steps that a projection picture image is acquired, the projection picture image comprises a first image area corresponding to a first projection picture and a second image area corresponding to a second projection picture, the first projection picture is generated by projection of a light machine on a projection plane, and the second projection picture is generated by projection of an auxiliary positioning device on the projection plane; performing projective transformation on second image position information of the second image area according to projective transformation relation information between first projection position information of the first projection picture and first image position information of the first image area to obtain second projection position information of a second projection picture; and measuring the off-axis ratio of the ray machine according to the relative installation size between the ray machine and the auxiliary positioning device, the first projection position information and the second projection position information. By adopting the method, the optical machine off-axis proportion measurement precision can be improved.

Description

Technical Field

[0001] The present application relates to the field of projection technology, and in particular to a method and device for measuring the off-axis ratio of an optical machine, and a projection device. Background Art

[0002] With the development of projection technology, projection correction technology has emerged. Projection correction technology can be used to correct irregularly shaped projection images, so that the projection images return to normal regular-shaped projection images. However, projection correction technology depends on the off-axis ratio of the optical machine.

[0003] In traditional technology, the off-axis ratio of the optical machine is equal to the distance from the center of the projection frame to the center of the optical axis divided by half of the projection frame bandwidth. Figure 1 When measuring the off-axis ratio of an optical machine, it is usually necessary to manually measure the projection frame bandwidth B and the distance A from the lower edge of the projection frame to the center of the optical axis, and then calculate the off-axis ratio of the optical machine based on A and B.

[0004] However, since the optical axis of the optical machine is invisible and the distance A is measured based on the optical axis of the optical machine, the accuracy of the manually measured distance A is not high, which will affect the measurement accuracy of the off-axis ratio of the optical machine. Summary of the invention

[0005] Based on this, it is necessary to provide an optical-mechanical off-axis ratio measurement method, device and projection equipment that can improve the accuracy of optical-mechanical off-axis ratio measurement in order to address the above technical problems.

[0006] In a first aspect, the present application provides a method for measuring an optical-mechanical off-axis ratio. The method comprises:

[0007] Acquire a projection screen image captured by a camera, wherein the projection screen image includes a first image area corresponding to a first projection screen and a second image area corresponding to a second projection screen, the first projection screen is generated by projecting an optical machine onto a projection plane, and the second projection screen is generated by projecting an auxiliary positioning device onto the projection plane;

[0008] According to the projective transformation relationship information between the first projection position information of the first projection picture and the first image position information of the first image area, projectively transform the second image position information of the second image area to obtain the second projection position information of the second projection picture;

[0009] The off-axis ratio of the optical machine is measured according to the relative installation dimensions between the optical machine and the auxiliary positioning device, the first projection position information, and the second projection position information.

[0010] In one embodiment, measuring the off-axis ratio of the optical machine according to the relative installation size between the optical machine and the auxiliary positioning device, the first projection position information, and the second projection position information includes:

[0011] According to the first projection position information and the second projection position information, measure the first relative distance from the picture center of the first projection picture to the optical axis center of the auxiliary positioning device; according to the first relative distance and the relative installation dimension, measure the second relative distance from the picture center of the first projection picture to the optical axis center of the optical machine, wherein the relative installation dimension is used to characterize the relative distance between the optical axis center of the optical machine and the optical axis center of the auxiliary positioning device; according to the second relative distance and the picture height of the first projection picture, determine the off-axis ratio of the optical machine.

[0012] In one embodiment, measuring a first relative distance from a center of the first projection image to a center of an optical axis of the auxiliary positioning device according to the first projection position information and the second projection position information includes:

[0013] According to the first projection position information, the center position of the first projection picture is located to obtain the first center position information; according to the first center position information and the second projection position information, the first relative distance is determined.

[0014] In one embodiment, the second projection image includes a line laser projection in a horizontal direction; and determining the first relative distance according to the first center position information and the second projection position information includes:

[0015] According to the second projection position information, the vertical position information of the line laser projection in the vertical direction is determined; according to the vertical position information and the first center position information, the relative distance between the center of the first projection screen and the line laser projection in the vertical direction is measured to obtain the first relative distance.

[0016] In one embodiment, the second projection picture includes structured light projection; and determining the first relative distance according to the first center position information and the second projection position information includes:

[0017] According to the second projection position information, the projection center position of the structured light projection is located to obtain the second center position information; according to the first center position information and the second center position information, the relative distance between the center of the picture and the projection center in the vertical direction is measured to obtain the first relative distance.

[0018] In one embodiment, the projective transformation relationship information includes a projective transformation matrix; performing a projective transformation on the second image position information of the second image area according to the projective transformation relationship information between the first projection position information of the first projection picture and the first image position information of the first image area to obtain the second projection position information of the second projection picture includes:

[0019] Perform image position recognition on the first image area to obtain the first image position information; perform image position recognition on the second image area to obtain the second image position information; determine the projection transformation matrix based on the first projection position information and the first image position information; perform projection transformation on the second image position information based on the projection transformation matrix to obtain the second projection position information.

[0020] In one embodiment, after the step of measuring the off-axis ratio of the optical machine according to the relative installation size between the optical machine and the auxiliary positioning device, the first projection position information and the second projection position information, the method further includes:

[0021] The resolution of the projection image and the projection ratio of the optical machine are obtained; and the projection image is corrected for the optical machine according to the resolution, the projection ratio and the off-axis ratio.

[0022] In a second aspect, the present application also provides an optical-mechanical off-axis ratio measurement device. The device comprises:

[0023] A captured image acquisition module, used to acquire a projection screen image captured by a camera, wherein the projection screen image includes a first image area corresponding to a first projection screen and a second image area corresponding to a second projection screen, the first projection screen is generated by projecting an optical machine onto a projection plane, and the second projection screen is generated by projecting an auxiliary positioning device onto the projection plane;

[0024] a projection transformation module, configured to perform a projection transformation on the second image position information of the second image area according to the projection transformation relationship information between the first projection position information of the first projection picture and the first image position information of the first image area, so as to obtain the second projection position information of the second projection picture;

[0025] A measuring module is used to measure the off-axis ratio of the optical machine according to the relative installation size between the optical machine and the auxiliary positioning device, the first projection position information and the second projection position information.

[0026] In a third aspect, the present application further provides a projection device. The projection device includes a memory and a processor, the memory stores a computer program, and the processor implements the following steps when executing the computer program:

[0027] Acquire a projection screen image taken by a camera, wherein the projection screen image includes a first image area corresponding to a first projection screen and a second image area corresponding to a second projection screen, the first projection screen is generated by projecting an optical machine onto a projection plane, and the second projection screen is generated by projecting an auxiliary positioning device onto the projection plane; perform a projective transformation on the second image position information of the second image area according to the projective transformation relationship information between the first projection position information of the first projection screen and the first image position information of the first image area to obtain the second projection position information of the second projection screen; measure the off-axis ratio of the optical machine according to the relative installation dimensions between the optical machine and the auxiliary positioning device, the first projection position information and the second projection position information.

[0028] In a fourth aspect, the present application further provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the following steps are implemented:

[0029] Acquire a projection screen image taken by a camera, wherein the projection screen image includes a first image area corresponding to a first projection screen and a second image area corresponding to a second projection screen, the first projection screen is generated by projecting an optical machine onto a projection plane, and the second projection screen is generated by projecting an auxiliary positioning device onto the projection plane; perform a projective transformation on the second image position information of the second image area according to the projective transformation relationship information between the first projection position information of the first projection screen and the first image position information of the first image area to obtain the second projection position information of the second projection screen; measure the off-axis ratio of the optical machine according to the relative installation dimensions between the optical machine and the auxiliary positioning device, the first projection position information and the second projection position information.

[0030] In a fifth aspect, the present application further provides a computer program product. The computer program product includes a computer program, and when the computer program is executed by a processor, the following steps are implemented:

[0031] Acquire a projection screen image taken by a camera, wherein the projection screen image includes a first image area corresponding to a first projection screen and a second image area corresponding to a second projection screen, the first projection screen is generated by projecting an optical machine onto a projection plane, and the second projection screen is generated by projecting an auxiliary positioning device onto the projection plane; perform a projective transformation on the second image position information of the second image area according to the projective transformation relationship information between the first projection position information of the first projection screen and the first image position information of the first image area to obtain the second projection position information of the second projection screen; measure the off-axis ratio of the optical machine according to the relative installation dimensions between the optical machine and the auxiliary positioning device, the first projection position information and the second projection position information.

[0032] The above-mentioned optical machine off-axis ratio measurement method, device and projection equipment obtain a projection screen image taken by a camera, wherein the projection screen image includes a first image area corresponding to a first projection screen and a second image area corresponding to a second projection screen, the first projection screen is generated by projecting the optical machine on a projection plane, and the second projection screen is generated by projecting the auxiliary positioning device on the projection plane; according to the projective transformation relationship information between the first projection position information of the first projection screen and the first image position information of the first image area, the second image position information of the second image area is projectively transformed to obtain the second projection position information of the second projection screen, so that the second projection position information of the second projection screen can be accurately obtained with the help of the projective transformation, thereby The off-axis ratio of the optical machine is measured according to the relative installation dimension between the optical machine and the auxiliary positioning device, the first projection position information and the second projection position information. Since the relative installation dimension determines the relative distance between the optical axis center of the optical machine and the optical axis center of the auxiliary positioning device, the off-axis ratio of the optical machine can be measured indirectly with the help of the relative distance between the optical axis center of the optical machine and the optical axis center of the auxiliary positioning device, the first projection position information and the second projection position information. During the entire measurement process, the relative installation dimension, the first projection position information and the second projection position information do not need to use the optical axis as a measurement reference. Therefore, the measurement accuracy of the first projection position information, the second projection position information and the relative installation dimension can be guaranteed, thereby ensuring the measurement accuracy of the off-axis ratio of the optical machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the principle of optical-mechanical off-axis ratio measurement in traditional technology;

[0034] Figure 2 A schematic diagram of a flow chart of a method for measuring an optical machine off-axis ratio in one embodiment;

[0035] Figure 3It is a schematic diagram of a camera capturing a projection screen image in one embodiment;

[0036] Figure 4 A schematic diagram of a flow chart of a method for measuring an optical-mechanical off-axis ratio in another embodiment;

[0037] Figure 5 A schematic diagram of the principle of using an auxiliary positioning device to perform optical-mechanical off-axis ratio measurement in one embodiment;

[0038] Figure 6 is a structural block diagram of an optical-mechanical off-axis ratio measuring device in one embodiment;

[0039] Figure 7 FIG. 4 is a diagram showing the internal structure of a projection device in one embodiment. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0041] In the present application, the method for measuring the off-axis ratio of an optical machine is applied to a projection device, which includes a camera, an optical machine and a projection screen. In the present application, an auxiliary positioning device is also provided. The auxiliary positioning device can be a part of the projection device body, or can be an additional device installed outside the projection device. The optical machine can project a first projection image on the projection screen, and the auxiliary positioning device can generate a second projection image on the projection screen for assisting in measuring the off-axis ratio of the optical machine.

[0042] In one embodiment, Figure 2 As shown, a method for measuring the off-axis ratio of an optical machine is provided, and the method is described by taking the application of the method to a projection device as an example, and the method includes the following steps:

[0043] Step 202, obtaining a projection screen image captured by a camera, wherein the projection screen image includes a first image area corresponding to a first projection screen and a second image area corresponding to a second projection screen, the first projection screen is generated by projecting an optical machine onto a projection plane, and the second projection screen is generated by projecting an auxiliary positioning device onto a projection plane.

[0044] Among them, the optical machine is used to project a first projection picture on a projection plane, and the auxiliary positioning device is used to project a second projection picture on the projection plane, and the projection plane is the plane where the projection screen is located; the camera can be a camera that comes with the projection device, which is used to capture the projection picture image for the projection plane, and the projection picture image at least includes a first image area corresponding to the first projection picture and a second image area corresponding to the second projection picture.

[0045] As an example, the auxiliary positioning device can be a line laser emitting device for emitting horizontal line lasers. Correspondingly, the second projection image presented on the projection plane is an image of line laser projection. At this time, the optical axis of the auxiliary positioning device is in the horizontal plane where the line laser projection is located.

[0046] As an example, the auxiliary positioning device can be a structured light emitting device for emitting structured light. Correspondingly, the second projection image presented on the projection plane is a structured light projection image. At this time, the optical axis of the auxiliary positioning device is perpendicular to the center position of the structured light projection, and the center position can be the geometric center of the structured light projection.

[0047] As an example, the structured light projection is a projection with a preset regular shape, the purpose of which is to facilitate the determination of the center position of the structured light projection. For example, the structured light projection may be a rectangular projection or a circular projection.

[0048] Step 204 , based on the projective transformation relationship information between the first projection position information of the first projection picture and the first image position information of the first image area, perform projective transformation on the second image position information of the second image area to obtain second projection position information of the second projection picture.

[0049] Among them, the first projection position information can be the key point position coordinates of the first projection picture in the projection plane, for example, if the first projection picture is a rectangular picture, then the first projection position information can be the position coordinates of the four vertices of the rectangular picture; the second projection position information can be the key point position coordinates of the second projection picture in the projection plane, for example, if the second projection picture is a line laser projection, then the first projection position information can be the position coordinates of multiple sampling points on the line laser projection; the first image position information is the key point position coordinates of the first image area in the captured image, for example, if the first projection picture is a rectangular picture, then the first image area can be a rectangular image area accordingly, so that the first image position information is the position coordinates of the four vertices of the rectangular image area; the second image position information is the key point position coordinates of the second image area in the captured image, for example, if the second projection picture is a line laser projection picture, then the second image area can be a line laser projection image accordingly, so that the second image position information is the position coordinates of multiple sampling points of the line laser projection in the linear image.

[0050] In addition, it should be noted that the points on the projection plane and the points on the camera image satisfy the projective transformation relationship, which is also called the homography transformation relationship. The projective transformation is used to map points on one projective plane to another projective plane, and to map straight lines to straight lines, which has the line-preserving property.

[0051] As an example, the projective transformation relationship information may be a projective transformation matrix, and the formula for satisfying the projective transformation relationship between the points on the projection plane and the points on the camera shooting screen is as follows:

[0052]

[0053] Among them, X 2 is the point position coordinate on the projection plane, X 1 is the coordinate of the point position on the screen taken by the camera, and H is the projection transformation matrix.

[0054] As an example, step 204 includes: obtaining first projection position information of the first projection screen; performing key point position identification on the projection screen image to obtain first image position information of the first image area and second image position information of the second image area; performing a projective transformation on the second image position information according to a projective transformation matrix between the first projection position information and the first image position information to obtain second projection position information of the second projection screen on the projection plane.

[0055] Step 206 , measuring the off-axis ratio of the optical machine according to the relative installation dimensions between the optical machine and the auxiliary positioning device, the first projection position information, and the second projection position information.

[0056] Among them, the relative installation dimension can be the relative distance between the installation position of the optical machine and the installation position of the auxiliary positioning device in the vertical direction. The relative installation dimension can be used to characterize the relative distance between the optical axis center of the optical machine and the optical axis center of the auxiliary positioning device in the vertical direction. In this way, after the optical machine and the auxiliary positioning device are simultaneously projected onto the projection plane to generate the first projection plane and the second projection plane, the relative distance from the center of the first projection picture to the center of the second projection plane can be determined according to the first projection position information of the first projection plane and the projection position information of the second projection plane. The center of the second projection plane is the optical axis center of the auxiliary positioning device. Therefore, the relative installation dimension and the relative distance from the center of the first projection picture to the center of the second projection plane can be used to determine the relative distance from the center of the first projection picture to the center of the optical axis of the optical machine. Finally, the relative distance from the center of the first projection picture to the center of the optical axis of the optical machine and the height of the first projection picture can be used to finally determine the off-axis ratio of the optical machine.

[0057] As an example, the installation position of the optical machine and the installation position of the auxiliary positioning device can be fixed by structural parts to ensure that the relative installation dimensions do not change, thereby ensuring that the relative installation dimensions corresponding to each optical machine are basically the same. In this way, when measuring the off-axis ratio of multiple optical machines, there is no need to measure the relative installation dimensions between each optical machine and the auxiliary positioning device. The relative installation dimensions can be directly recorded in the instruction manual of the optical machine, thereby improving the efficiency of batch measurement of the off-axis ratio of optical machines.

[0058] As an example, see Figure 3 , Figure 3 : is a schematic diagram of a camera shooting a projection screen image in an embodiment, wherein the sensor responsible for positioning is an auxiliary positioning device, t0 is the relative installation size between the auxiliary positioning device and the optical machine, abcd is the first image area, Figure 3 The line laser shown in is the captured image area of ​​the line laser projection, that is, the second image area. Figure 3 The structured light shown in is the captured image area of ​​the structured light projection, that is, the second image area, so the auxiliary positioning device in this embodiment can selectively generate line laser projection or structured light projection on the projection screen.

[0059] As an example, step 206 includes: measuring a first relative distance from the picture center of the first projection picture to the optical axis center of the auxiliary positioning device according to the first projection position information and the second projection position information; measuring a second relative distance from the picture center of the first projection picture to the optical axis center of the optical machine according to the first relative distance and the relative installation size; and calculating the off-axis ratio of the optical machine according to the second relative matrix and the picture height of the first projection picture.

[0060] As an example, the calculation formula of the off-axis ratio of the optical machine is as follows:

[0061] offset=[D / (B / 2)]*100%

[0062] Wherein, offset is the off-axis ratio of the optical machine, D is the second relative distance from the center of the first projection image to the center of the optical axis of the optical machine, and B is the image height of the first projection image.

[0063] As an example, after the optical machine is rotated in the vertical direction or the horizontal direction, the projected image of the optical machine can be corrected using the measured off-axis ratio of the optical machine.

[0064] In the above-mentioned optical machine off-axis ratio measurement method, a projection screen image taken by a camera is obtained, wherein the projection screen image includes a first image area corresponding to the first projection screen and a second image area corresponding to the second projection screen, the first projection screen is generated by the optical machine on the projection plane, and the second projection screen is generated by the auxiliary positioning device on the projection plane; according to the projective transformation relationship information between the first projection position information of the first projection screen and the first image position information of the first image area, the second image position information of the second image area is projectively transformed to obtain the second projection position information of the second projection screen, so that the second projection position information of the second projection screen can be accurately obtained with the help of the projective transformation, thereby obtaining the second projection position information of the second projection screen according to the relationship between the optical machine and the auxiliary positioning device. The off-axis ratio of the optical machine is measured by using the relative installation dimension, the first projection position information and the second projection position information. Since the relative installation dimension determines the relative distance between the optical axis center of the optical machine and the optical axis center of the auxiliary positioning device, the off-axis ratio of the optical machine can be measured indirectly with the help of the relative distance between the optical axis center of the optical machine and the optical axis center of the auxiliary positioning device, the first projection position information and the second projection position information. During the entire measurement process, the relative installation dimension, the first projection position information and the second projection position information do not need to use the optical axis as a measurement reference. Therefore, the measurement accuracy of the first projection position information, the second projection position information and the relative installation dimension can be guaranteed, thereby ensuring the measurement accuracy of the off-axis ratio of the optical machine.

[0065] In one embodiment, Figure 4 As shown, according to the relative installation size between the optical machine and the auxiliary positioning device, the first projection position information and the second projection position information, the off-axis ratio of the optical machine is measured, including:

[0066] Step 302: measuring a first relative distance from the center of the first projection image to the center of the optical axis of the auxiliary positioning device according to the first projection position information and the second projection position information.

[0067] Among them, the auxiliary positioning device can be configured to emit linear laser or structured light directly toward the projection plane, so that the picture center of the second projection picture is the optical axis center of the optical axis of the auxiliary positioning device on the projection plane, and the relative distance between the picture center of the first projection picture and the picture center of the second projection in the vertical direction is the first relative distance from the picture center of the first projection picture to the optical axis center of the auxiliary positioning device.

[0068] As an example, step 302 includes: locating the screen center position of the first projection screen according to the first projection position information to obtain the first center position information; locating the screen center position of the second projection screen according to the second projection position information to obtain the second center position information; measuring the relative distance between the screen center of the first projection screen and the screen center of the second projection screen in the vertical direction according to the first center position information and the second center position information to obtain the first relative distance from the screen center of the first projection screen to the optical axis center of the auxiliary positioning device.

[0069] In one embodiment, measuring a first relative distance from the center of the first projection image to the center of the optical axis of the auxiliary positioning device according to the first projection position information and the second projection position information includes:

[0070] According to the first projection position information, the center position of the first projection picture is located to obtain the first center position information; according to the first center position information and the second projection position information, the first relative distance is determined.

[0071] The first projection position information may be a plurality of key point coordinates of the first projection screen, the second projection position information may be a plurality of key point coordinates of the second projection screen, and the first center position information may be the first center position coordinates.

[0072] Specifically, according to the coordinates of multiple key points of the first projection picture, the center position of the first projection picture is located to obtain the first center position coordinates; according to the coordinates of multiple key points of the second projection picture, the position of the optical axis center of the auxiliary positioning device in the vertical direction is located to obtain the vertical position coordinates of the optical axis center of the auxiliary positioning device in the vertical direction; according to the first center position coordinates and the vertical position coordinates, the first relative distance from the picture center of the first projection picture to the optical axis center of the auxiliary positioning device is calculated.

[0073] Step 304, measuring the second relative distance from the center of the first projection image to the center of the optical axis of the optical machine based on the first relative distance and the relative installation dimension, wherein the relative installation dimension is used to characterize the relative distance between the center of the optical axis of the optical machine and the center of the optical axis of the auxiliary positioning device.

[0074] Among them, the optical axis center of the optical machine can be the regional position center of the intersection area between the optical axis of the optical machine and the projection plane, and the optical axis center of the auxiliary positioning device can be the regional position center of the intersection area between the optical axis of the auxiliary positioning device and the projection plane; the relative installation dimension can be used to characterize the relative distance in the vertical direction between the optical axis center of the optical machine and the optical axis center of the auxiliary positioning device on the projection plane, that is, the relative distance in the vertical direction between the optical axis of the optical machine and the optical axis of the auxiliary positioning device.

[0075] As an example, step 304 includes: determining the relative position relationship between the optical axis of the optical machine and the optical axis of the auxiliary positioning device in the vertical direction; calculating the second relative distance from the center of the first projection image to the center of the optical axis of the optical machine based on the relative position relationship, the first relative distance and the relative installation size.

[0076] As an example, calculating the second relative distance from the center of the first projection screen to the center of the optical axis of the optical machine according to the relative position relationship, the first relative distance and the relative installation size includes:

[0077] If the optical axis of the optical machine and the optical axis of the auxiliary positioning device are on the same horizontal plane, the first relative distance is used as the second relative distance from the center of the first projection picture to the center of the optical axis of the optical machine; if the optical axis of the optical machine is above the optical axis of the auxiliary positioning device, the difference between the first relative distance and the relative installation dimension is calculated to obtain the second relative distance from the center of the first projection picture to the center of the optical axis of the optical machine; if the optical axis of the optical machine is below the optical axis of the auxiliary positioning device, the sum of the first relative distance and the relative installation dimension is calculated to obtain the second relative distance from the center of the first projection picture to the center of the optical axis of the optical machine.

[0078] Step 306, determining the off-axis ratio of the optical machine according to the second relative distance and the image height of the first projection image.

[0079] As an example, step 306 includes: dividing the second relative distance by half of the height of the first projection picture to obtain the off-axis ratio of the optical machine.

[0080] As an example, see Figure 5 , where the camera screen is the camera shooting plane, the DMD plane is the projection plane, ABCD is the first projection screen, the resolution is 1920*1080, EF is the line laser projection, that is, the first projection screen, abcd is the first image area, ef is the second image area, O is the center of the first projection screen, and the calculation formula of the off-axis ratio of the optical machine in this embodiment is as follows:

[0081] offset=(OH+t0) / OG*100%

[0082] Among them, offset is the off-axis ratio of the optical machine, OH is the first relative distance from the center of the first projection screen to the center of the optical axis of the auxiliary positioning device, if the optical axes of the optical machine and the auxiliary positioning device are on the same horizontal plane, then t0 is 0; if the optical axis of the optical machine is above the optical axis of the auxiliary positioning device, then t0 is a negative value relative to the installation size; if the optical axis of the optical machine is below the optical axis of the auxiliary positioning device, then t0 is a positive value relative to the installation size, OG half of the screen height of the first projection screen.

[0083] In this embodiment, the first relative distance from the picture center of the first projection picture to the optical axis center of the auxiliary positioning device is measured according to the first projection position information and the second projection position information; the second relative distance from the picture center of the first projection picture to the optical axis center of the optical machine is measured according to the first relative distance and the relative installation dimension. Since the relative installation dimension is used to characterize the relative distance between the optical axis center of the optical machine and the optical axis center of the auxiliary positioning device, it is possible to quantitatively measure the second relative distance from the picture center of the first projection picture to the optical axis center of the optical machine with the help of the relative installation dimension. Therefore, the off-axis ratio of the optical machine can be determined according to the second relative distance and the picture height of the first projection picture. Since the first projection position information, the second projection position information and the relative installation dimension are not measured based on the optical axis, the measurement accuracy of the first projection position information, the second projection position information and the relative installation dimension can be guaranteed even if the optical axis is not visible. Therefore, the measurement accuracy of the off-axis ratio of the optical machine can be guaranteed.

[0084] In one embodiment, the second projection picture includes a line laser projection in a horizontal direction; determining the first relative distance according to the first center position information and the second projection position information includes:

[0085] According to the second projection position information, the vertical position information of the line laser projection in the vertical direction is determined; according to the vertical position information and the first center position information, the relative distance between the center of the first projection screen and the line laser projection in the vertical direction is measured to obtain the first relative distance.

[0086] The second projection position information may be the coordinates of a plurality of key points of the line laser projection, the first center position information may be the first center position coordinates, and the vertical position information may be the vertical direction coordinates.

[0087] Specifically, the vertical coordinates in the coordinates of multiple key points of the line laser projection are averaged to obtain the vertical position coordinates of the optical axis center of the auxiliary positioning device in the vertical direction; the difference between the vertical position coordinates and the vertical coordinates in the first center position coordinates is calculated to obtain the first relative distance between the center of the first projection screen and the line laser projection in the vertical direction.

[0088] In the above embodiment, a line laser projection can be formed on the projection plane by emitting a line laser by relying on the auxiliary positioning device. Based on the coordinates of multiple key points on the line laser projection, the position of the optical axis center of the auxiliary positioning device in the vertical direction can be accurately located to obtain the vertical position coordinates. Therefore, according to the vertical position coordinates and the vertical coordinates in the first center position coordinates, the first relative distance between the center of the first projection picture and the line laser projection in the vertical direction can be quantitatively calculated, thereby ensuring the measurement accuracy of the first relative distance, thereby laying a foundation for improving the measurement accuracy of the optical machine off-axis ratio.

[0089] In one embodiment, the second projection picture includes structured light projection; determining the first relative distance according to the first center position information and the second projection position information includes:

[0090] According to the second projection position information, the projection center position of the structured light projection is located to obtain the second center position information; according to the first center position information and the second center position information, the relative distance between the center of the fixed screen and the projection center in the vertical direction is measured to obtain the first relative distance.

[0091] The second projection position information may be the coordinates of a plurality of key points of structured light projection, the first center position information may be the first center position coordinates, and the second center position information may be the second center position coordinates.

[0092] Specifically, according to the coordinates of multiple key points of the structured light projection, the projection center position of the structured light projection is located to obtain the second center position coordinates; the difference between the vertical coordinates in the first center position coordinates and the vertical coordinates in the second center position coordinates is calculated to obtain the first relative distance between the center of the first projection screen and the line laser projection in the vertical direction.

[0093] In the above-mentioned embodiment, by emitting structured light with the help of an auxiliary positioning device, a structured light projection can be formed on the projection plane. Based on the coordinates of multiple key points on the structured light projection, the projection center position of the structured light projection can be accurately located to obtain the second center position coordinates. Thus, according to the vertical coordinates in the first center position coordinates and the vertical coordinates in the second center position coordinates, the first relative distance in the vertical direction between the center of the first projection picture and the line laser projection can be quantitatively calculated, thereby ensuring the measurement accuracy of the first relative distance and laying a foundation for improving the measurement accuracy of the off-axis ratio of the optical machine.

[0094] In one embodiment, the projective transformation relationship information includes a projective transformation matrix; performing a projective transformation on the second image position information of the second image area according to the projective transformation relationship information between the first projection position information of the first projection picture and the first image position information of the first image area to obtain the second projection position information of the second projection picture includes:

[0095] Perform image position recognition on the first image area to obtain first image position information; perform image position recognition on the second image area to obtain second image position information; determine a projection transformation matrix based on the first projection position information and the first image position information; perform projection transformation on the second image position information based on the projection transformation matrix to obtain second projection position information.

[0096] Among them, the first image position information can be multiple first image position coordinates, the second image position information can be multiple second image position coordinates, the first projection position information can be multiple first projection position coordinates, that is, multiple key point coordinates of the first projection screen, and the second projection position information can be multiple second projection position coordinates, that is, multiple key point coordinates of the second projection screen.

[0097] Specifically, by performing image recognition on the first image area, the position coordinates of each key point in the first image area are identified to obtain a plurality of first image position coordinates; by performing image recognition on the second image area, the position coordinates of each key point in the second image area are identified to obtain a plurality of second image position coordinates; based on the plurality of first image position coordinates and the plurality of first projection position coordinates, the projective transformation matrix between the camera shooting plane and the projection plane is calculated; based on the projective transformation matrix, the plurality of second image position coordinates are projectively transformed to obtain a plurality of second projection position coordinates.

[0098] In the above embodiment, the first image position information is obtained by performing image position recognition on the first image area; the second image position information is obtained by performing image position recognition on the second image area; the projection transformation matrix is ​​determined according to the first projection position information and the first image position information; and the second image position information is projectively transformed according to the projection transformation matrix to obtain the second projection position information. This achieves quantitative measurement of the position coordinates of multiple key points in the second projection image without relying on the optical axis as a measurement reference. Therefore, the measurement accuracy of the second projection position information can be guaranteed, laying a foundation for improving the measurement accuracy of the off-axis ratio of the optical machine.

[0099] When using an optical machine, it will inevitably rotate vertically or horizontally. At this time, the projection image of the optical machine is no longer rectangular, but trapezoidal, which affects the projection effect. In order to improve the projection effect, it is necessary to correct the projection image of the optical machine, that is, perform anti-trapezoidal correction.

[0100] The correction of the projection image depends on the off-axis ratio of the optical machine. At present, if the theoretical off-axis ratio in the optical machine manual is used to correct the projection image, due to process reasons, there are certain differences between the theoretical off-axis ratio and the actual off-axis ratio of each optical machine, which will affect the correction effect of the projection image; if the off-axis ratio of the optical machine is measured by manually measuring the distance from the lower edge of the projection frame to the center of the optical axis, since the optical axis of the optical machine is invisible, and the distance from the lower edge of the projection frame to the center of the optical axis is measured based on the optical axis of the optical machine, the manual measurement of the distance from the lower edge of the projection frame to the center of the optical axis is not accurate, which leads to low measurement accuracy of the off-axis ratio of the optical machine, which will also affect the correction effect of the projection image.

[0101] In one embodiment, after the step of measuring the off-axis ratio of the optical machine according to the relative installation size between the optical machine and the auxiliary positioning device, the first projection position information and the second projection position information, the method further comprises:

[0102] Obtain the resolution of the projected image and the projection ratio of the optical machine; correct the projection image of the optical machine according to the resolution, projection ratio and off-axis ratio.

[0103] Among them, the projection ratio of the optical machine is equal to the projection distance of the optical machine divided by the projection screen width of the optical machine.

[0104] Specifically, the resolution of the projection screen and the projection ratio of the optical machine are obtained, and the projection screen height and the projection screen width are determined according to the resolution of the projection screen; the four vertex coordinates of the corrected matrix projection screen are calculated according to the projection screen height, projection screen width, projection ratio and eccentricity ratio, and the optical machine is corrected for the projection screen according to the four vertex coordinates.

[0105] As an example, according to the projection screen height, projection screen width, projection ratio and off-axis ratio, the calculation process of calculating the coordinates of the four vertices of the corrected matrix projection screen is as follows:

[0106] The coordinates of the upper left vertex (x 1 ,y 1 , z 1 ):

[0107] x 1 =-length / 2

[0108] y 1 =height*(offset / 2+0.5)

[0109] z 1 =Q*length

[0110] The coordinates of the upper right vertex (x 2 ,y 2 , z2 ):

[0111] x 2 =length / 2

[0112] y 2 =height*(offset / 2+0.5)

[0113] z 2 =Q*length

[0114] The coordinates of the lower left vertex (x 3 ,y 3 , z 3 ):

[0115] x 3 =-length / 2

[0116] y 3 = height*(offset / 2-0.5)

[0117] z 3 =Q*length

[0118] The coordinates of the lower right vertex (x 4 ,y 4 , z 4 ):

[0119] x 4 =length / 2

[0120] y 4 = height*(offset / 2-0.5)

[0121] z 4 =Q*length

[0122] Among them, length is the width of the projection screen, height is the height of the projection screen, Q is the projection ratio, and offset is the off-axis ratio of the optical machine.

[0123] As an example, the resolution of the projection screen is equal to the projection screen height*projection screen width.

[0124] In the above embodiment, after measuring the off-axis ratio of the optical machine, the resolution of the projection image and the projection ratio of the optical machine are obtained; according to the resolution, projection ratio and off-axis ratio, the projection image correction of the optical machine can be achieved, wherein, since the measurement of the off-axis ratio of the optical machine does not rely on the optical axis as the measurement reference of the size, the measurement accuracy of the off-axis ratio of the optical machine is higher. Therefore, performing the projection image correction based on the off-axis ratio of the optical machine with higher accuracy can improve the accuracy of the projection image correction, so that the effect of the projection image correction is better.

[0125] In one embodiment, a projection screen image captured by a camera is first obtained, wherein the projection screen image includes a first image area corresponding to a first projection screen and a second image area corresponding to a second projection screen, the first projection screen is generated by projecting an optical machine on a projection plane, and the second projection screen is generated by projecting an auxiliary positioning device on the projection plane; first projection position information of the first projection screen is obtained; key point positions are identified on the projection screen image to obtain first image position information of the first image area and second image position information of the second image area; according to a projective transformation matrix between the first projection position information and the first image position information, the second image position information is projectively transformed to obtain second projection position information of the second projection screen on the projection plane, so that the position of the second projection screen can be located on the projection plane based on the projective transformation relationship between the shooting plane and the projection plane to obtain the second projection position information.

[0126] After acquiring the second projection position information, the picture center position of the first projection picture is located according to the first projection position information to obtain the first center position information; the picture center position of the second projection picture is located according to the second projection position information to obtain the second center position information; according to the first center position information and the second center position information, the relative distance in the vertical direction between the picture center of the first projection picture and the picture center of the second projection is measured to obtain the first relative distance from the picture center of the first projection picture to the center of the optical axis of the auxiliary positioning device, thereby measuring the first relative distance from the picture center of the first projection picture to the center of the optical axis of the auxiliary positioning device without relying on the optical axis as a measurement reference, and ensuring the measurement accuracy of the first relative distance.

[0127] After measuring the first relative distance, determine the relative position relationship between the optical axis of the optical machine and the optical axis of the auxiliary positioning device in the vertical direction. If the optical axis of the optical machine and the optical axis of the auxiliary positioning device are on the same horizontal plane, use the first relative distance as the second relative distance from the center of the first projection picture to the center of the optical axis of the optical machine; if the optical axis of the optical machine is above the optical axis of the auxiliary positioning device, calculate the difference between the first relative distance and the relative installation dimension to obtain the second relative distance from the center of the first projection picture to the center of the optical axis of the optical machine; if the optical axis of the optical machine is below the optical axis of the auxiliary positioning device, calculate the sum of the first relative distance and the relative installation dimension to obtain the second relative distance from the center of the first projection picture to the center of the optical axis of the optical machine. In this way, the second relative distance from the center of the first projection picture to the center of the optical axis of the optical machine can be quantitatively measured with the help of the relative installation dimension. The measurement process also does not rely on the optical axis as a measurement reference, so the measurement accuracy of the second relative distance can be guaranteed.

[0128] After measuring the second relative distance, divide the second relative distance by half of the height of the first projection screen to obtain the off-axis ratio of the optical machine. Since the first relative distance, the second relative distance and the height of the first projection screen do not rely on the optical axis as a measurement reference, it is possible to quantitatively measure the off-axis ratio of the optical axis without relying on the optical axis as a size measurement reference, thereby ensuring the measurement accuracy of the off-axis ratio of the optical axis. Therefore, the projection screen can be corrected based on the more accurate off-axis ratio of the optical machine, which can improve the accuracy of the projection screen correction and achieve better projection screen correction effects.

[0129] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages 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 to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0130] Based on the same inventive concept, the embodiment of the present application also provides an optical-mechanical off-axis ratio measuring device for implementing the optical-mechanical off-axis ratio measuring method involved above. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme recorded in the above method, so the specific limitations in the embodiments of one or more optical-mechanical off-axis ratio measuring devices provided below can refer to the limitations of the optical-mechanical off-axis ratio measuring method above, and will not be repeated here.

[0131] In one embodiment, Figure 6 As shown, an optical-mechanical off-axis ratio measuring device is provided, comprising: an image acquisition module, a projection transformation module and a measurement module, wherein:

[0132] A shooting image acquisition module is used to acquire a projection screen image captured by a camera, wherein the projection screen image includes a first image area corresponding to a first projection screen and a second image area corresponding to a second projection screen, the first projection screen is generated by projecting an optical machine onto a projection plane, and the second projection screen is generated by projecting an auxiliary positioning device onto the projection plane.

[0133] A projection transformation module is used to perform a projection transformation on the second image position information of the second image area according to the projection transformation relationship information between the first projection position information of the first projection picture and the first image position information of the first image area, so as to obtain the second projection position information of the second projection picture.

[0134] A measuring module is used to measure the off-axis ratio of the optical machine according to the relative installation size between the optical machine and the auxiliary positioning device, the first projection position information and the second projection position information.

[0135] In one embodiment, the measuring module is further used for:

[0136] According to the first projection position information and the second projection position information, measure the first relative distance from the picture center of the first projection picture to the optical axis center of the auxiliary positioning device; according to the first relative distance and the relative installation dimension, measure the second relative distance from the picture center of the first projection picture to the optical axis center of the optical machine, wherein the relative installation dimension is used to characterize the relative distance between the optical axis center of the optical machine and the optical axis center of the auxiliary positioning device; according to the second relative distance and the picture height of the first projection picture, determine the off-axis ratio of the optical machine.

[0137] In one embodiment, the measuring module is further used for:

[0138] According to the first projection position information, the center position of the first projection picture is located to obtain the first center position information; according to the first center position information and the second projection position information, the first relative distance is determined.

[0139] In one embodiment, the second projection picture includes a line laser projection in a horizontal direction; and the measuring module is further used for:

[0140] According to the second projection position information, the vertical position information of the line laser projection in the vertical direction is determined; according to the vertical position information and the first center position information, the relative distance between the center of the first projection screen and the line laser projection in the vertical direction is measured to obtain the first relative distance.

[0141] In one embodiment, the second projection picture includes structured light projection; and the measurement module is further used for:

[0142] According to the second projection position information, the projection center position of the structured light projection is located to obtain the second center position information; according to the first center position information and the second center position information, the relative distance between the center of the picture and the projection center in the vertical direction is measured to obtain the first relative distance.

[0143] In one embodiment, the projective transformation relationship information includes a projective transformation matrix; and the projective transformation module is further used to:

[0144] Perform image position recognition on the first image area to obtain the first image position information; perform image position recognition on the second image area to obtain the second image position information; determine the projection transformation matrix based on the first projection position information and the first image position information; perform projection transformation on the second image position information based on the projection transformation matrix to obtain the second projection position information.

[0145] In one embodiment, the optical-mechanical off-axis ratio measuring device further comprises:

[0146] The projection picture correction module is used to obtain the resolution of the projection picture and the projection ratio of the optical machine; and perform projection picture correction on the optical machine according to the resolution, the projection ratio and the off-axis ratio.

[0147] Each module in the above optical machine off-axis ratio measurement device can be implemented in whole or in part by software, hardware, or a combination thereof. Each module can be embedded in or independent of the processor in the projection device in the form of hardware, or can be stored in the memory in the projection device in the form of software, so that the processor can call and execute the operations corresponding to each module.

[0148] In one embodiment, a projection device is provided. The projection device may be a terminal, and its internal structure diagram may be as follows: Figure 7 As shown. The projection device includes a processor, a memory, a communication interface, an optical machine and an input device connected through a system bus. Among them, the processor of the projection device is used to provide computing and control capabilities. The memory of the projection device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the projection device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a method for measuring the off-axis ratio of an optical machine is implemented.

[0149] In one embodiment, the projection device may further include an auxiliary positioning device, and the auxiliary positioning device is used to generate a second projection picture on the projection plane.

[0150] Those skilled in the art will understand that Figure 7The structure shown in the figure is only a block diagram of a part of the structure related to the scheme of the present application, and does not constitute a limitation on the projection device to which the scheme of the present application is applied. The specific projection device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0151] In one embodiment, a projection device is provided, including a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the computer program, the following steps are implemented:

[0152] Acquire a projection screen image taken by a camera, wherein the projection screen image includes a first image area corresponding to a first projection screen and a second image area corresponding to a second projection screen, the first projection screen is generated by projecting an optical machine onto a projection plane, and the second projection screen is generated by projecting an auxiliary positioning device onto the projection plane; perform a projective transformation on the second image position information of the second image area according to the projective transformation relationship information between the first projection position information of the first projection screen and the first image position information of the first image area to obtain the second projection position information of the second projection screen; measure the off-axis ratio of the optical machine according to the relative installation dimensions between the optical machine and the auxiliary positioning device, the first projection position information and the second projection position information.

[0153] In one embodiment, when the processor executes the computer program, the following steps are also implemented:

[0154] According to the first projection position information and the second projection position information, measure the first relative distance from the picture center of the first projection picture to the optical axis center of the auxiliary positioning device; according to the first relative distance and the relative installation dimension, measure the second relative distance from the picture center of the first projection picture to the optical axis center of the optical machine, wherein the relative installation dimension is used to characterize the relative distance between the optical axis center of the optical machine and the optical axis center of the auxiliary positioning device; according to the second relative distance and the picture height of the first projection picture, determine the off-axis ratio of the optical machine.

[0155] In one embodiment, when the processor executes the computer program, the following steps are also implemented:

[0156] According to the first projection position information, the center position of the first projection picture is located to obtain the first center position information; according to the first center position information and the second projection position information, the first relative distance is determined.

[0157] In one embodiment, the second projection screen includes a line laser projection in a horizontal direction; when the processor executes the computer program, the following steps are further implemented:

[0158] According to the second projection position information, the vertical position information of the line laser projection in the vertical direction is determined; according to the vertical position information and the first center position information, the relative distance between the center of the first projection screen and the line laser projection in the vertical direction is measured to obtain the first relative distance.

[0159] In one embodiment, the second projection picture includes structured light projection; when the processor executes the computer program, the following steps are further implemented:

[0160] According to the second projection position information, the projection center position of the structured light projection is located to obtain the second center position information; according to the first center position information and the second center position information, the relative distance between the center of the picture and the projection center in the vertical direction is measured to obtain the first relative distance.

[0161] In one embodiment, the projective transformation relationship information includes a projective transformation matrix; when the processor executes the computer program, the processor further implements the following steps:

[0162] Perform image position recognition on the first image area to obtain the first image position information; perform image position recognition on the second image area to obtain the second image position information; determine the projection transformation matrix based on the first projection position information and the first image position information; perform projection transformation on the second image position information based on the projection transformation matrix to obtain the second projection position information.

[0163] In one embodiment, when the processor executes the computer program, the following steps are also implemented:

[0164] The resolution of the projection image and the projection ratio of the optical machine are obtained; and the projection image is corrected for the optical machine according to the resolution, the projection ratio and the off-axis ratio.

[0165] In one embodiment, a computer readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented:

[0166] Acquire a projection screen image taken by a camera, wherein the projection screen image includes a first image area corresponding to a first projection screen and a second image area corresponding to a second projection screen, the first projection screen is generated by projecting an optical machine onto a projection plane, and the second projection screen is generated by projecting an auxiliary positioning device onto the projection plane; perform a projective transformation on the second image position information of the second image area according to the projective transformation relationship information between the first projection position information of the first projection screen and the first image position information of the first image area to obtain the second projection position information of the second projection screen; measure the off-axis ratio of the optical machine according to the relative installation dimensions between the optical machine and the auxiliary positioning device, the first projection position information and the second projection position information.

[0167] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0168] According to the first projection position information and the second projection position information, measure the first relative distance from the picture center of the first projection picture to the optical axis center of the auxiliary positioning device; according to the first relative distance and the relative installation dimension, measure the second relative distance from the picture center of the first projection picture to the optical axis center of the optical machine, wherein the relative installation dimension is used to characterize the relative distance between the optical axis center of the optical machine and the optical axis center of the auxiliary positioning device; according to the second relative distance and the picture height of the first projection picture, determine the off-axis ratio of the optical machine.

[0169] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0170] According to the first projection position information, the center position of the first projection picture is located to obtain the first center position information; according to the first center position information and the second projection position information, the first relative distance is determined.

[0171] In one embodiment, the second projection screen includes a line laser projection in a horizontal direction; when the computer program is executed by the processor, the following steps are further implemented:

[0172] According to the second projection position information, the vertical position information of the line laser projection in the vertical direction is determined; according to the vertical position information and the first center position information, the relative distance between the center of the first projection screen and the line laser projection in the vertical direction is measured to obtain the first relative distance.

[0173] In one embodiment, the second projection picture includes structured light projection; when the computer program is executed by the processor, the following steps are further implemented:

[0174] According to the second projection position information, the projection center position of the structured light projection is located to obtain the second center position information; according to the first center position information and the second center position information, the relative distance between the center of the picture and the projection center in the vertical direction is measured to obtain the first relative distance.

[0175] In one embodiment, the projective transformation relationship information includes a projective transformation matrix; when the computer program is executed by a processor, the following steps are also implemented:

[0176] Perform image position recognition on the first image area to obtain the first image position information; perform image position recognition on the second image area to obtain the second image position information; determine the projection transformation matrix based on the first projection position information and the first image position information; perform projection transformation on the second image position information based on the projection transformation matrix to obtain the second projection position information.

[0177] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0178] The resolution of the projection image and the projection ratio of the optical machine are obtained; and the projection image is corrected for the optical machine according to the resolution, the projection ratio and the off-axis ratio.

[0179] In one embodiment, a computer program product is provided, comprising a computer program, which, when executed by a processor, implements the following steps:

[0180] Acquire a projection screen image taken by a camera, wherein the projection screen image includes a first image area corresponding to a first projection screen and a second image area corresponding to a second projection screen, the first projection screen is generated by projecting an optical machine onto a projection plane, and the second projection screen is generated by projecting an auxiliary positioning device onto the projection plane; perform a projective transformation on the second image position information of the second image area according to the projective transformation relationship information between the first projection position information of the first projection screen and the first image position information of the first image area to obtain the second projection position information of the second projection screen; measure the off-axis ratio of the optical machine according to the relative installation dimensions between the optical machine and the auxiliary positioning device, the first projection position information and the second projection position information.

[0181] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0182] According to the first projection position information and the second projection position information, measure the first relative distance from the picture center of the first projection picture to the optical axis center of the auxiliary positioning device; according to the first relative distance and the relative installation dimension, measure the second relative distance from the picture center of the first projection picture to the optical axis center of the optical machine, wherein the relative installation dimension is used to characterize the relative distance between the optical axis center of the optical machine and the optical axis center of the auxiliary positioning device; according to the second relative distance and the picture height of the first projection picture, determine the off-axis ratio of the optical machine.

[0183] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0184] According to the first projection position information, the center position of the first projection picture is located to obtain the first center position information; according to the first center position information and the second projection position information, the first relative distance is determined.

[0185] In one embodiment, the second projection screen includes a line laser projection in a horizontal direction; when the computer program is executed by the processor, the following steps are further implemented:

[0186] According to the second projection position information, the vertical position information of the line laser projection in the vertical direction is determined; according to the vertical position information and the first center position information, the relative distance between the center of the first projection screen and the line laser projection in the vertical direction is measured to obtain the first relative distance.

[0187] In one embodiment, the second projection picture includes structured light projection; when the computer program is executed by the processor, the following steps are further implemented:

[0188] According to the second projection position information, the projection center position of the structured light projection is located to obtain the second center position information; according to the first center position information and the second center position information, the relative distance between the center of the picture and the projection center in the vertical direction is measured to obtain the first relative distance.

[0189] In one embodiment, the projective transformation relationship information includes a projective transformation matrix; when the computer program is executed by a processor, the following steps are also implemented:

[0190] Perform image position recognition on the first image area to obtain the first image position information; perform image position recognition on the second image area to obtain the second image position information; determine the projection transformation matrix based on the first projection position information and the first image position information; perform projection transformation on the second image position information based on the projection transformation matrix to obtain the second projection position information.

[0191] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0192] The resolution of the projection image and the projection ratio of the optical machine are obtained; and the projection image is corrected for the optical machine according to the resolution, the projection ratio and the off-axis ratio.

[0193] Those skilled 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 the memory, database or other medium used in the embodiments provided in the present 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), magnetoresistive 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. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0194] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, 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.

[0195] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A method for measuring the off-axis ratio of an optical machine, characterized in that: The method comprises: Acquire a projection screen image captured by a camera, wherein the projection screen image includes a first image area corresponding to a first projection screen and a second image area corresponding to a second projection screen, the first projection screen is generated by projecting an optical machine onto a projection plane, and the second projection screen is generated by projecting an auxiliary positioning device onto the projection plane; According to the projective transformation relationship information between the first projection position information of the first projection picture and the first image position information of the first image area, projectively transform the second image position information of the second image area to obtain the second projection position information of the second projection picture; The off-axis ratio of the optical machine is measured according to the relative installation dimensions between the optical machine and the auxiliary positioning device, the first projection position information, and the second projection position information.

2. The method according to claim 1, characterized in that The measuring the off-axis ratio of the optical machine according to the relative installation size between the optical machine and the auxiliary positioning device, the first projection position information and the second projection position information includes: Measuring a first relative distance from a center of the first projection image to a center of an optical axis of the auxiliary positioning device according to the first projection position information and the second projection position information; According to the first relative distance and the relative installation dimension, measure a second relative distance from the center of the first projection screen to the center of the optical axis of the optical machine, wherein the relative installation dimension is used to characterize the relative distance between the center of the optical axis of the optical machine and the center of the optical axis of the auxiliary positioning device; The off-axis ratio of the optical machine is determined according to the second relative distance and the screen height of the first projection screen.

3. The method according to claim 2, characterized in that The measuring, according to the first projection position information and the second projection position information, a first relative distance from the center of the first projection image to the center of the optical axis of the auxiliary positioning device comprises: Locating the center position of the first projection picture according to the first projection position information to obtain first center position information; The first relative distance is determined according to the first center position information and the second projection position information.

4. The method according to claim 3, characterized in that The second projection picture includes a line laser projection in a horizontal direction; and determining the first relative distance according to the first center position information and the second projection position information includes: Determining vertical position information of the line laser projection in a vertical direction according to the second projection position information; According to the vertical position information and the first center position information, the relative distance between the center of the first projection screen and the line laser projection in the vertical direction is measured to obtain the first relative distance.

5. The method according to claim 3, characterized in that: The second projection picture includes structured light projection; and determining the first relative distance according to the first center position information and the second projection position information includes: According to the second projection position information, locate the projection center position of the structured light projection to obtain second center position information; The relative distance between the center of the picture and the center of the projection in the vertical direction is measured according to the first center position information and the second center position information to obtain the first relative distance.

6. The method according to claim 1, characterized in that The projective transformation relationship information includes a projective transformation matrix; the projective transformation is performed on the second image position information of the second image area according to the projective transformation relationship information between the first projection position information of the first projection picture and the first image position information of the first image area to obtain the second projection position information of the second projection picture, including: Performing image position recognition on the first image area to obtain the first image position information; Performing image position recognition on the second image area to obtain the second image position information; Determining the projective transformation matrix according to the first projection position information and the first image position information; According to the projective transformation matrix, the second image position information is projectively transformed to obtain the second projection position information.

7. The method according to any one of claims 1 to 6, characterized in that: After the step of measuring the off-axis ratio of the optical machine according to the relative installation size between the optical machine and the auxiliary positioning device, the first projection position information and the second projection position information, the method further includes: Obtaining the resolution of the projection image and the projection ratio of the optical machine; The projection image of the optical machine is corrected according to the resolution, the projection ratio and the off-axis ratio.

8. An optical-mechanical off-axis ratio measuring device, characterized in that: The device comprises: A captured image acquisition module, used to acquire a projection screen image captured by a camera, wherein the projection screen image includes a first image area corresponding to a first projection screen and a second image area corresponding to a second projection screen, the first projection screen is generated by projecting an optical machine onto a projection plane, and the second projection screen is generated by projecting an auxiliary positioning device onto the projection plane; a projection transformation module, configured to perform a projection transformation on the second image position information of the second image area according to the projection transformation relationship information between the first projection position information of the first projection picture and the first image position information of the first image area, so as to obtain the second projection position information of the second projection picture; A measuring module is used to measure the off-axis ratio of the optical machine according to the relative installation size between the optical machine and the auxiliary positioning device, the first projection position information and the second projection position information.

9. A projection device, comprising an optical machine, a memory and a processor, wherein the memory stores a computer program, characterized in that: The optical machine is used to generate a first projection picture on a projection plane, and the processor implements the steps of the method described in any one of claims 1 to 7 when executing the computer program.

10. The projection device according to claim 9, characterized in that: The projection device further comprises an auxiliary positioning device, and the auxiliary positioning device is used to generate a second projection picture on the projection plane.

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