WO2011143813A1

WO2011143813A1 - Object projection method and object projection sysytem

Info

Publication number: WO2011143813A1
Application number: PCT/CN2010/072907
Authority: WO
Inventors: 吴迪; 陈�光
Original assignee: 深圳泰山在线科技有限公司
Priority date: 2010-05-19
Filing date: 2010-05-19
Publication date: 2011-11-24
Also published as: CN102939562A; CN102939562B

Abstract

An object projection method includes: acquiring the three-dimensional coordinates corresponding to the matching point-pair (P₀and P₁) of the object in the first video camera (21) and the second video camera (22); acquiring the affine projection matrix of the third video camera (32); calculating the theoretical barycentric coordinates of the object in the third video camera (32); calculating the theoretical projection size of the object in the third video camera (32); acquiring the actual barycentric coordinates of the projection of the object in the third video camera (32); acquiring the actual projection size of the object in the third video camera (32); and judging whether the three-dimensional coordinates corresponding to the matching point-pair (P₀and P₁) is right or not. An object projection system using the method is also provided.

Description

Description book projection method and system

The present invention relates to a target projection method and a target projection system using the same, and more particularly to a target projection method having a verification process and a target projection system using the same. Background technique

In systems where cameras are used to obtain information, it is critical to extract the correct information from the image. The judgment of the correctness of the target recognition mainly depends on the shape, color and size of the target. The matching of the recognition targets between the two cameras mainly depends on the polar constraint and the order consistency constraint. In a system using a binocular camera, the principle of parallax is used to establish a three-dimensional object. The disadvantage of such a system is that it is more difficult to identify, match and establish correctness of the target. Summary of the invention

The technical problem to be solved by the present invention is that it is difficult to verify the correctness of the three-dimensional coordinate recognition, matching and establishment of the target projection system of the prior art, and provides an affine transformation between the target and the single camera by using the dual camera. Relationship, a target projection method that verifies the recognition, matching and reconstruction of the target onto the projected image, verifies the three-dimensional coordinate recognition, matching and establishing the correctness according to the projected image, and the target projection system using the method.

The technical solution adopted by the present invention to solve the technical problem thereof is: constructing a target projection method, which includes:

Obtaining a corresponding three-dimensional coordinate of the matching point pair of the target in the first camera and the second camera; acquiring an affine projection matrix of the third camera;

Verification process:

Calculating the target object on the third camera according to an affine projection matrix of the third camera and a matching point pair of the target in the first camera and the second camera Theoretical center of gravity coordinates;

Calculating a theoretical projection size of the target on the third camera according to the matching point to the corresponding three-dimensional coordinates;

Obtaining an actual center of gravity coordinate of the target projected on the third camera;

Obtaining an actual projected size of the target on the third camera;

And determining, according to the comparison result of the theoretical barycentric coordinates and the actual barycentric coordinates, and the comparison result of the theoretical projection size and the actual projection size, whether the corresponding three-dimensional coordinates of the matching point pair are correct.

The target projection method according to the present invention, wherein the matching point pairs are obtained by a calibration process and a three-dimensional coordinate establishment process by corresponding three-dimensional coordinates:

a calibration process: using a calibration parameter of the first camera and the second camera, obtaining a first correction matrix of the first camera that corrects the first camera and the second camera to a parallel camera, and the a second correction matrix of the second camera;

a three-dimensional coordinate establishing process: matching pairs of the target objects in the first camera and the second camera by matching target recognition of the first camera and the second camera; using the first The correction matrix, the second correction matrix, and the matching point pair calculate three-dimensional coordinates corresponding to the matching point pair.

According to the target projection method of the present invention, the calibration parameter includes an internal parameter and an external matching parameter, and the internal parameter is obtained by a stereo calibration plate calibration method, and the external matching parameter matches the first camera and the fixed order in a fixed order. The coordinate data collected by the second camera is then obtained by performing a nonlinear least squares optimization using the Levenberg-Marquard algorithm to match the coordinate data acquired by the first camera and the second camera.

a ϊ "0" the target projection method according to the present invention, wherein the internal parameter includes A 0 α _γ ν ₀

0 0 1 a _x = fl dx, a _y = fl dy, where / is the camera focal length, dx, ^ are the pixel spacing in the horizontal and vertical directions, respectively, is the optical center of the camera, is the u-axis and the V-axis Non-vertical factor; radial distortion parameters kl, k2 _; tangential distortion parameters pl, p2 _; the external matching parameters include rotation matrix parameters

And translation matrix parameters

The target projection method of the present invention, wherein the affine projection matrix is obtained by: acquiring at least 6 sets of different positions of the matching point pairs corresponding to the three-dimensional coordinates and the matching point pairs corresponding to the third Two-dimensional coordinates projected on the camera;

The affine projection matrix is calculated by a linear least squares method according to the corresponding three-dimensional coordinates of the matching points of the at least six different sets of positions and the two-dimensional coordinates of the matching point pairs projected on the third camera.

The target projection method according to the present invention, wherein the capturing three-dimensional coordinates of the matching point pairs of at least 6 sets of different positions and the two-dimensional coordinates of the matching point pairs corresponding to the projection on the third camera pass the following Method obtained:

Setting a third camera as a coordinate system, and taking at least 6 sets of two-dimensional coordinates of different positions from the coordinate system;

Obtaining and comparing the two-dimensional coordinates projected by the target to the matching point on the third camera and the two-dimensional coordinates of the at least six different positions from the coordinate system Corresponding three-dimensional coordinates of the matching point pairs of at least 6 different positions corresponding to at least 6 sets of different positions of the two-dimensional coordinates.

Constructing a target projection system, comprising a processing unit, an imaging unit, further comprising a verification unit, the imaging system comprising a first camera and a second camera, the verification unit comprising a verification module and a third camera:

The processing unit is configured to acquire a three-dimensional coordinate corresponding to a matching point pair of the target in the first camera and the second camera; and acquire an affine projection matrix of the third camera;

The verification module is configured to calculate the target object in the third according to an affine projection matrix of the third camera and a matching point pair of the target in the first camera and the second camera Theoretical center of gravity coordinates on the camera;

Obtaining an actual center of gravity coordinate of the target projected on the third camera; Obtaining an actual projected size of the target on the third camera;

And determining, according to the comparison result of the theoretical barycentric coordinates and the actual barycentric coordinates, and the comparison result of the theoretical projection size and the actual projected size of the 222, whether the corresponding three-dimensional coordinates of the matching point pair are correct. 333

The target projection system of the present invention, wherein the processing unit comprises a calibration module and a three-dimensional coordinate creation module:

The calibration module: configured to use the calibration parameters of the first camera and the second camera to obtain a first correction of the first camera that corrects the first camera and the second camera into parallel cameras a matrix and a second correction matrix of the second camera;

The three-dimensional coordinate establishing module is configured to obtain a matching point pair of the target object in the first camera and the second camera by matching target recognition of the first camera and the second camera; The first correction matrix, the second correction matrix, and the matching point pair calculate three-dimensional coordinates corresponding to the matching point pair.

The target projection system of the present invention, wherein the calibration parameter includes an internal parameter and an external matching parameter, the internal parameter is obtained by a stereo calibration plate calibration method, and the external matching parameter matches the first camera and the fixed order The coordinate data collected by the second camera is then obtained by performing a nonlinear least squares optimization using the Levenberg-Marquard algorithm to match the coordinate data acquired by the first camera and the second camera.

a ϊ "0" the target projection system of the present invention, wherein the internal parameters include A 0 a _y v ₀

0 0 1 a _x = fl dx, a _y = fl dy , where / is the focal length of the camera, dx, the pixel spacing in the horizontal and vertical directions, respectively, is the optical center of the camera, is the u-axis and the V-axis Non-vertical factor; radial distortion parameters kl, k2 _; tangential distortion parameters pl, p2 _; the external matching parameters include rotation matrix parameters

And translation matrix parameters

The target projection system of the present invention, wherein the affine projection matrix is obtained by the following method: Collecting corresponding three-dimensional coordinates of the matching point pairs of at least 6 different sets of positions and corresponding two-dimensional coordinates of the matching point pairs projected on the third camera;

The target projection system of the present invention, wherein the matching three-dimensional coordinates of the matching point pairs of at least six sets of different positions and the two-dimensional coordinates of the matching point pairs corresponding to the projection on the third camera pass the following Method obtained:

The target projection system of the present invention, wherein the first camera and the second camera are equipped with an infrared transmission filter.

The object projection system of the present invention, wherein the verification unit comprises at least two of the third target imaging systems of the present invention, wherein the imaging unit further comprises at least one imaging camera.

The target projection method embodying the present invention and the target projection system using the same have the following beneficial effects: Adding a third camera with a verification module based on the original target projection system, using the established three-dimensional coordinates and the two-dimensional coordinates The mapping, verifying the accuracy of 3D coordinate recognition, matching and establishing results.

The calibration parameters acquired in advance make the target projection process simpler and more accurate; the acquisition of the internal parameters and the external matching parameters makes the first correction matrix of the first camera and the second correction matrix of the second camera more accurate, the first camera and the second camera Parallel correction is more efficient; the calculation of the affine projection matrix makes it possible to accurately calculate the first projection size on the third camera; and the affine projection matrix can Obtained by a plurality of methods; the first camera and the second camera are equipped with an infrared transmission filter, which eliminates interference of visible light, and the three-dimensional coordinates are more accurately established; and the verification by the multi-camera with the verification module is further increased. The correctness of the identification, matching and establishment of the dual cameras is judged; the verification unit can also be used in a target projection imaging system of multiple cameras (three or more). DRAWINGS

The present invention will be further described below in conjunction with the accompanying drawings and embodiments, in which:

1 is a schematic structural view of a preferred embodiment of a target projection system of the present invention;

2A is an image for calibration of internal parameters and external matching parameters of a calibration camera of a preferred embodiment of the target projection system of the present invention; FIG.

2B is an image for calibration of internal parameters and external matching parameters of another sub-calibration camera of the preferred embodiment of the target projection system of the present invention;

3 is a two-dimensional coordinate arrangement and coordinate value diagram of matching points of eight sets of different positions for calculating an affine projection matrix of a preferred embodiment of the target projection system of the present invention. detailed description

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail in conjunction with the drawings.

As shown in FIG. 1 , in the target projection method of the present invention, a calibration process, a three-dimensional coordinate establishment process, and a verification process are included, wherein the calibration parameters of the first camera 21 and the second camera 22 utilized in the three-dimensional coordinate establishment process are as follows Obtained:

The calibration parameters of the camera include internal parameters and external matching parameters.

Internal parameter calibration:

The internal parameters of the camera are fixed for the fixed focus camera system. Internal parameters include:

A-

a _x = fl dx, a = fl dy , where "is the camera focal length, dx, respectively

0 0 1 The pixel spacing in the horizontal direction and the vertical direction is the optical center of the camera, which is the non-vertical factor of the U-axis and the V-axis; the radial distortion parameters kl, k2 _{; the} tangential distortion parameters pl, p2. The meter uses the stereo calibration plate calibration method to calibrate the internal parameters of all cameras. Calibration image as shown

2A, 2B are shown. After all the cameras have acquired the calibration image, the connectivity of the connected domain is used to obtain the coordinates of the center of gravity of all the calibration blocks. Then use these data information to calibrate the camera's internal parameters according to the plate calibration method. The calibration method is currently used and can be implemented with different calibration methods.

External matching parameter calibration:

The external camera is mainly the relative positional relationship between the cameras, including

Rotation matrix parameter

The center of gravity coordinates of the block imaging are calibrated using the first camera 21 and the second camera 22 acquired as described above. The coordinate data acquired by the two cameras is matched in a fixed order. Then, using the Levenberg-Marquardt algorithm for nonlinear minimum optimization, the fixed order matches the coordinate data acquired by the first camera 21 and the second camera 22 to obtain the final camera calibration parameters. The final parameters include internal parameters of the respective cameras of the first camera 21 and the second camera 22 and external matching parameters between the two cameras. The implementation method of this step is not unique.

Calibration process: Using the calibration parameters of the first camera 21 and the second camera 22, the two camera acquisition images are corrected to parallel cameras; the implementation method of this step is not unique.

a. Calculating the first correction matrix of the first camera 21: setting the virtual point of the calibration in the coordinate system of the first camera 21 = ( ^{Q 0 2000} ),

According to the formula:

Calculate the coordinates of the virtual point in the coordinate system of the first camera 21 (according to the formula:

R, +R

p ¹⁷ oi +p【

The column vectors in the first correction matrix are calculated separately. Obtaining the first positive matrix of the first camera 21 according to the formula (2): 2

b. Calculating the second correction matrix of the second camera 22: setting the virtual point for calibration in the coordinate system of the second camera 22 = ( ^{Q 0 2000} )

According to the formula:

Pn=RPu + T (4) Calculate the coordinates of the virtual point in the coordinate system of the second camera 22. According to the formula:

The column vectors in the second correction matrix are calculated separately. The second correction matrix of the second camera 22 is obtained according to the formula (5):

Oh,

(6).

The three-dimensional coordinate establishing process: by matching the target recognition of the first camera 21 and the second imaging; 22, the corresponding matching point pairs of the target are obtained: A circular reflective object is used as the target identifier. The target camera is identified by the support vector machine classifier trained by the circular reflective object sample in the first camera 21 and the second camera 22, respectively, and the target is calculated to be imaged in the first camera 21 and the second camera 22. Match the pair of points (the barycentric coordinates) and then use the polar constraint and the order consistency constraint to achieve the correct match of the target.

Calculating corresponding three-dimensional coordinates of the pair of matching points by using the first correction matrix, the second correction matrix, and the matching point pair;

a. Pixel point coordinate distortion correction, and the matching point will be P. And becomes undistorted image coordinates and one. The iterative calculation is used here to correct the coordinates.

b. Correct the image coordinate calculation according to the formula:

Po

c. The target three-dimensional coordinates are established according to the formula:

Disparity = _Pl [l] - ¹ ], where sum is the image _x coordinate (9)

Β ξ + ζ Zc=B氺1.0 /Disparity; Xc=B氺p _Q [l] /Disparity; (10) Yc=Zc * 7 ₀ [1]/1.0; The implementation method of this step is not unique.

The verification process: the three-dimensional coordinate establishing process obtains the corresponding three-dimensional coordinate P of the matching point pair; according to the affine projection matrix of the third camera 32 and the target in the first camera 21 and the second camera The matching point in machine 22 is P. The three-dimensional coordinate P corresponding to Pi counts the matching point pair P. And coordinates on the third camera 32

/ / (12);

Calculating the theoretical center of gravity coordinates of the target on the third camera 32 according to the coordinate Q on the third camera 32 according to the matching point of the target: The method is a known target identifier size, here is a circular target Object diameter D, third camera

The focal length f of 32 and the three-dimensional coordinate P of the target, and then calculate the projected circle radius of the circular target according to the formula:

Radius = Dx f IP _z (13) · Calculate the theoretical projection size of the object on the third camera 32 based on the coordinates of the matching point on the third camera 32:

Drawing on the image of the third camera 32 is centered on the theoretical center of gravity coordinates, and Radius is a solid circle of radius;

Obtaining an actual center of gravity coordinate of the target projected on the third camera 32;

Obtaining the actual projected size of the object on the third camera 32 based on the coordinates of the matching point on the third camera 32:

Whether the difference between the theoretical barycentric coordinates and the actual barycentric coordinates projected by the target on the third camera 32 is less than a first set value and whether the difference between the theoretical projection size and the actual projection size is smaller than the second setting The fixed values jointly determine the matching point pair P. And the corresponding 3D coordinates are correct. When both judgments are smaller than the set value, it is considered that the matching point is correct for the recognition, matching and establishment of the corresponding three-dimensional coordinates.

As shown in Figure 3 (Figure 3 uses 640 * 480 resolution, other resolutions can be modified accordingly), the affine projection matrix used in the verification process is obtained by the following method: At least 6 sets (8 sets in FIG. 3) of the matching point pairs and corresponding three-dimensional coordinates Q and the matching point pairs P are collected at different positions. And corresponding to the two-dimensional coordinates projected on the third camera 32:

The third camera 32 is set to be a coordinate system, and two sets of two-dimensional coordinates of different positions in the coordinate system are taken; when the target moves to the matching point pair P. And when the two-dimensional coordinates projected on the third camera 32 and the two-dimensional coordinates of the eight different positions in the coordinate system of the third camera 32 are coincident, the two-dimensional coordinates corresponding to the eight sets of different positions are obtained. 8 pairs of different positions of the matching point pairs Po and corresponding three-dimensional coordinates ^

Establish the equation formula:

Ax= b (15)

The affine projection matrix parameter is where (14) can be abbreviated as

3⁄4o 3⁄4i a ₁₂ (15) ; Calculate the parameter X using linear least squares:

x= {A ^T Ay ^l A ^T b ( ₁₆ ). Collecting at least 6 sets of the matching point pairs P at different positions. The three-dimensional coordinates corresponding to Pi and the matching point pair P. And the method corresponding to the two-dimensional coordinates projected on the third camera 32 can also be realized by correct matching recognition, establishing at least 6 sets of corresponding three-dimensional coordinates and two-dimensional coordinates.

As a preferred embodiment of the present invention, the implementation of the present invention requires at least three cameras and maintains the synchronism of the captured images of the camera. The first camera 21 and the second camera 22 for three-dimensional coordinate establishment are equipped with infrared transmission filters. Camera through the first camera 21 and the second camera 22 The three-dimensional coordinates of the captured image can effectively eliminate the interference of visible light, and the three-dimensional coordinates are more accurate. This setting can be selected according to actual needs.

As a preferred embodiment of the invention, the verification unit 3 comprises at least two third cameras 32 for verifying the established three-dimensional coordinates. The verification of multiple cameras with a verification module further increases the correctness of the identification, matching and establishment of the dual cameras. You can choose the number of cameras to use for verification based on actual accuracy.

As a preferred embodiment of the present invention, the imaging unit 2 may be a multi-camera (greater than or equal to three) target projection imaging system, which may increase the accuracy of judging the recognition, matching and establishment of the multi-camera.

The above is only the embodiment of the present invention, and thus does not limit the scope of the patent of the present invention. The equivalent structural transformation made by using the specification and the drawings of the present invention, or directly or indirectly applied to other related technical fields, is the same. The scope of the invention is included in the scope of the patent protection of the present invention.

Claims

Claim

A target projection method, comprising:

Obtaining a matching point pair (and corresponding three-dimensional coordinates of the object in the first camera (21) and the second camera (22);

Obtaining an affine projection matrix of the third camera (32);

Verification process:

Calculating according to the affine projection matrix of the third camera (32) and the matching point pair (P. and P corresponding to the three-dimensional coordinates of the target in the first camera (21) and the second camera (22) The theoretical center of gravity coordinates of the target on the third camera (32);

Calculating a theoretical projection size of the target on the third camera (32) according to the matching point pair (P. and P corresponding to the three-dimensional coordinates;

Obtaining an actual barycentric coordinate projected by the target on the third camera (32); obtaining an actual projected size of the target on the third camera (32); according to the theoretical barycentric coordinates and the The comparison result of the actual barycentric coordinates and the comparison result of the theoretical projection size and the actual projection size jointly determine whether the matching point pair (P. and the corresponding three-dimensional coordinates are correct).

2. The target projection method according to claim 1, wherein the matching point pairs (Ρ, and P correspond to three-dimensional coordinates obtained by a calibration process and a three-dimensional coordinate establishment process:

Calibration process: using the calibration parameters of the first camera (21) and the second camera (22), obtaining the correction of the first camera (21) and the second camera (22) into parallel cameras a first correction matrix of the first camera (21) and a second correction matrix of the second camera (22);

a three-dimensional coordinate establishing process: the object is obtained by the target recognition of the first camera (21) and the second camera (22) at the first camera (21) and the second camera (22) Matching point pairs (P. and PJ; using the first correction matrix, the second correction matrix, and the matching point pair (P. and P calculate the matching point pair (P. and P corresponding) The three-dimensional coordinates.

The target projection method according to claim 2, wherein the calibration parameter comprises an internal parameter and an external matching parameter, and the internal parameter is obtained by a stereo calibration plate calibration method, The external matching parameter meters match the coordinate data acquired by the first camera (21) and the second camera (22) in a fixed order, and then perform the nonlinear least squares optimization by the Levenberg-Marquard algorithm. The coordinate data acquired by the first camera (21) and the second camera (22) are sequentially matched to obtain.

The target projection method according to claim 3, wherein the internal parameter package a _x γ "o

Including ^ = 0 a _y v ₀ a fl dx, a = fl dy , where "is the camera focal length, dx, dy^

0 0 1 is not the pixel spacing between the horizontal direction and the vertical direction, is the optical center of the camera, is the non-vertical factor of the u-axis and the V-axis; radial distortion kl, k2 _; tangential distortion parameters pl, p2 _; External

Matching parameters including rotation matrix parameters

The target projection method according to claim 1, wherein the affine projection matrix is obtained by the following method:

Collecting at least 6 sets of matching point pairs at different locations. Three-dimensional coordinates corresponding to P and the pair of matching points (P. and PJ correspond to two-dimensional coordinates projected on the third camera (32);

According to the matching point pair of the at least 6 sets of different positions (the three-dimensional coordinates corresponding to P and P and the matching point pair (P. and P correspond to the two-dimensional coordinates projected on the third camera (32)) The affine projection matrix is calculated by linear least squares method.

The target projection method according to claim 5, wherein the acquiring at least 6 sets of different pairs of matching point pairs (P. and PJ corresponding three-dimensional coordinates and the matching point pair (P. and The two-dimensional coordinates of the PJ corresponding to the projection on the third camera (32) are obtained by the following methods:

Setting a third camera (32) as a coordinate system, and taking at least 6 sets of two-dimensional coordinates of different positions from the coordinate system;

Movement of the target to the pair of matching points (P. and P. 2D coordinates projected on the third camera (32) and 2D from the coordinate system taking at least 6 different positions When the coordinates coincide, the matching of at least 6 different sets of positions corresponding to the two-dimensional coordinates of the at least 6 different positions is obtained Point pair (P. and PJ corresponding to the three-dimensional coordinates.

7. A target projection system, comprising a processing unit (1), an imaging unit (2), further comprising a verification unit (3), the imaging system (2) comprising a first camera (21) and a second a camera (22), the verification unit (3) comprising a verification module (31) and a third camera (32):

The processing unit (1) is configured to acquire a matching point pair (P. and P corresponding to the three-dimensional coordinates of the object in the first camera (21) and the second camera (22); and acquire the third camera (32) Affine projection matrix;

The verification module (31): configured to match a pair of points according to the affine projection matrix of the third camera (32) and the target in the first camera (21) and the second camera (22) (and Calculating a theoretical center of gravity coordinate of the target on the third camera (32) according to the corresponding three-dimensional coordinates; calculating the target in the third camera according to the matching point pair (the three-dimensional coordinates corresponding to P and P) Theoretical projection size;

Obtaining an actual barycentric coordinate projected by the target on the third camera (32); obtaining an actual projected size of the target on the third camera (32);

And determining, according to a comparison result of the theoretical barycentric coordinates and the actual barycentric coordinates, and a comparison result of the theoretical projection size and the actual projection size, whether the three-dimensional coordinates corresponding to the matching point pair (P. and P) are correct.

8. The target projection system according to claim 7, wherein the processing unit (1) comprises a calibration module (11) and a three-dimensional coordinate creation module (12):

The calibration module (11) is configured to obtain the first camera (21) and the second camera (22) by using calibration parameters of the first camera (21) and the second camera (22) Correcting a first correction matrix of the first camera (21) of the parallel camera and a second correction matrix of the second camera (22);

The three-dimensional coordinate establishing module (12): configured to obtain the target object in the first camera (21) by matching target recognition of the first camera (21) and the second camera (22) Matching point pairs (P. and PJ in the second camera (22); calculating the matching points by using the first correction matrix, the second correction matrix, and the matching point pair (P. and P) The three-dimensional coordinates corresponding to (P. and P).

9. The target projection system according to claim 8, wherein the calibration parameter comprises an internal parameter and an external matching parameter, the internal parameter is obtained by a stereo calibration plate calibration method, and the external matching parameter is matched by a fixed order. The coordinate data collected by the first camera (21) and the second camera (22) are then subjected to nonlinear least squares optimization using the Levinberg-Marquard algorithm to match the first camera to the fixed sequence ( 21) and coordinate data acquired by the second camera (22) are obtained.

The target projection system according to claim 9, wherein said internal parameter package a _x γ "o

Include = 0 a _y v ₀ a fl dx, a = fl dy , where / is the camera focal length, ώ:, dy^

Matching parameters including rotation matrix parameters

The target projection system according to claim 7, wherein the affine projection matrix is obtained by the following method:

Collecting at least 6 sets of different pairs of matching point pairs (P. and P corresponding to the three-dimensional coordinates and the matching point pair (P. and P corresponding to the two-dimensional coordinates projected on the third camera (32);

12. The target projection system according to claim 11, wherein the acquiring at least 6 sets of different pairs of matching point pairs (P. and P corresponding to three-dimensional coordinates and the matching point pair (P. and P corresponding to the two-dimensional coordinates projected on the third camera (32) is obtained by: setting a third camera (32) as a coordinate system, and taking at least 6 sets of two-dimensional coordinates of different positions from the coordinate system;

When the target moves to the matching point pair (P. and P on the third camera (32) When the two-dimensional coordinates of the projection coincide with the two-dimensional coordinates of the at least six different positions from the coordinate system, the matching of at least six different positions corresponding to the two-dimensional coordinates of the at least six different positions is obtained. Point pair (P. and P corresponding to the three-dimensional coordinates.

The target projection system according to claim 7, wherein the first camera (21) and the second camera (22) are mounted with an infrared transmission filter.

14. Target projection system according to claim 7, characterized in that the verification unit (3) comprises at least two of the third cameras (32).

The target projection system according to claim 7, characterized in that the imaging unit (2) further comprises at least one imaging camera.