A three-dimensional imaging system and method

Abstract

The present disclosure relates to a kind of three-dimensional imaging system and method, the system includes camera, first set of mirrors, second set of mirrors and three-dimensional imaging module, the first set of mirrors is used to reflect the incident light from the object to be measured on the second set of mirrors, and determine first virtual optical center and second virtual optical center based on the extension line of the incident light;The second set of mirrors is used to reflect the incident light from the first set of mirrors on the camera, so that the camera acquires the two-dimensional image of the object to be measured;The three-dimensional imaging module is used to carry out three-dimensional imaging processing to the two-dimensional image based on first to fifth coordinate system, obtains the target three-dimensional image of the object to be measured. When carrying out three-dimensional imaging using the embodiment of the present disclosure, the three-dimensional imaging system uses monocular to double eye stereo vision measurement method to measure the three-dimensional coordinates of object, and carries out three-dimensional imaging, the system is simple and ingenious, and the implementation method is more simple.

Description

Technical Field

[0001] This disclosure relates to the field of three-dimensional imaging technology, and in particular to a three-dimensional imaging system, method and apparatus. Background Technology

[0002] Three-dimensional imaging technology can measure the three-dimensional coordinates of an object and then create a three-dimensional image of it to obtain specific shape and location information. Three-dimensional imaging technology has a wide range of applications. For example, in the field of autonomous driving, when a user is driving a vehicle on a complex road, three-dimensional imaging technology can be used to detect obstacles on the road and create a three-dimensional image of them to obtain shape and location information.

[0003] In related technologies, 3D imaging methods include binocular stereo vision, fringe projection structured light, laser triangulation, and Time-of-Flight (ToF) methods. Binocular stereo vision measures 3D coordinates using a binocular stereo vision system, typically consisting of two cameras. Simulating human vision and based on the principle of parallax, and knowing the positional relationship between the two cameras, it acquires the 3D coordinates of the object within the common field of view of the two cameras, and then obtains a 3D image of the object based on these coordinates. Fringe projection projects a carrier frequency fringe onto the surface of the object, and uses an imaging device to acquire a deformed fringe image modulated by the height of the object from another angle. This deformed fringe image is then demodulated to reconstruct a 3D image of the object.

[0004] However, in related technologies, when using the binocular stereo vision method alone for 3D imaging, it is first necessary to calibrate the two cameras in the binocular stereo vision system separately (single-camera calibration), then calibrate the matrix transformation relationship between the two cameras (binocular calibration), and match the disparity maps of the two cameras to obtain the 3D coordinates of the object under test. This presents technical problems such as the binocular stereo vision system being inflexible and the binocular stereo vision method being relatively complex. On the other hand, when using the fringe projection method alone for 3D imaging, the imaging accuracy of the fringe projection method is easily affected by the nonlinearity of the projector and camera and environmental changes. This method is prone to errors caused by equipment and environmental factors. Summary of the Invention

[0005] This disclosure provides a three-dimensional imaging system, method, and apparatus to at least address the problems of inflexibility and computational complexity of binocular stereo vision systems used in three-dimensional imaging using binocular stereoscopic methods, and the susceptibility to errors caused by equipment and environmental factors when using fringe projection methods for three-dimensional imaging. The technical solution of this disclosure is as follows:

[0006] According to one aspect of the embodiments of this disclosure, a three-dimensional imaging system is provided, comprising:

[0007] Camera, first set of reflectors, second set of reflectors, and 3D imaging module;

[0008] The camera faces the object to be tested; the reflective surfaces of the first set of reflectors face the object to be tested; the first set of reflectors is used to reflect the incident light from the object to be tested onto the second set of reflectors, and to determine the first virtual optical center and the second virtual optical center based on the extension of the incident light.

[0009] The second set of reflectors is located inside the first set of reflectors; the second set of reflectors is used to reflect the incident light reflected by the first set of reflectors onto the camera, so that the camera can acquire a two-dimensional image of the object under test;

[0010] According to a second aspect of the present disclosure, a three-dimensional imaging method is provided, comprising:

[0011] Based on the first set of mirrors in the three-dimensional imaging system, the incident light from the object under test is reflected onto the second set of mirrors in the three-dimensional imaging system;

[0012] The incident light reflected by the first set of reflectors is reflected by the second set of reflectors onto the camera in the three-dimensional imaging system, so that the camera can acquire a two-dimensional image of the object under test.

[0013] The first virtual optical center and the second virtual optical center are determined based on the extension of the incident light ray;

[0014] Based on the first coordinate system, the second coordinate system, the third coordinate system, the fourth coordinate system, and the fifth coordinate system, the two-dimensional image is subjected to three-dimensional imaging processing to obtain the target three-dimensional image of the object under test;

[0015] Wherein, the first coordinate system is a two-dimensional coordinate system with the first virtual optical center as the origin; the second coordinate system is a three-dimensional coordinate system with the first virtual optical center as the origin; the third coordinate system is a two-dimensional coordinate system with the second virtual optical center as the origin; the fourth coordinate system is a three-dimensional coordinate system with the second virtual optical center as the origin; and the fifth coordinate system is a three-dimensional coordinate system with the midpoint of the line connecting the first virtual optical center and the second virtual optical center as the origin.

[0016] According to a third aspect of the present disclosure, a three-dimensional imaging apparatus is provided, comprising:

[0017] The first reflection module is used to reflect incident light from the object under test onto the second set of reflections in the three-dimensional imaging system based on the first set of reflections in the three-dimensional imaging system.

[0018] The second reflection module is used to reflect the incident light from the first set of reflectors onto the camera in the three-dimensional imaging system based on the second set of reflectors, so that the camera can acquire a two-dimensional image of the object under test;

[0019] The virtual optical center determination module determines the first virtual optical center and the second virtual optical center based on the extension line of the incident light ray;

[0020] The target 3D image acquisition module is used to perform 3D imaging processing on the 2D image based on the first coordinate system, the second coordinate system, the third coordinate system, the fourth coordinate system, and the fifth coordinate system to obtain the target 3D image of the object to be tested.

[0021] The technical solutions provided by the embodiments of this disclosure have at least the following beneficial effects:

[0022] In performing 3D imaging, a 3D imaging system is first established, which includes: a camera; a first set of reflectors for reflecting incident light from the object under test onto a second set of reflectors, and determining a first virtual optical center and a second virtual optical center based on the extension of the incident light; a second set of reflectors for reflecting incident light from the first set of reflectors onto the camera, so that the camera can acquire a 2D image of the object under test; and a 3D imaging module for performing 3D imaging processing on the 2D image based on a first coordinate system, a second coordinate system, a third coordinate system, a fourth coordinate system, and a fifth coordinate system to obtain a target 3D image of the object under test.

[0023] Based on this system, when the object under test is within the effective field of view of the camera, the incident light from the object passes sequentially through the first and second sets of reflectors and is finally reflected onto the camera. The camera can then acquire a two-dimensional image of the object. Simultaneously, the first and second virtual optical centers established in this system can be considered as the virtual optical centers of two virtual cameras. Five coordinate systems are established based on these virtual optical centers, realizing a stereoscopic vision measurement method that converts a single camera (the real camera) to a binocular camera (two virtual cameras). In other words, this system can complete three-dimensional coordinate measurement based on binocular stereoscopic vision using only one camera. The three-dimensional imaging module in this system performs three-dimensional imaging processing on the two-dimensional image acquired by the camera based on the aforementioned five coordinate systems, ultimately obtaining a three-dimensional image of the object under test. When performing three-dimensional imaging on the object under test, the three-dimensional coordinates of the object can be measured using a single-to-binocular stereoscopic vision measurement method, and a three-dimensional image of the object can be obtained. The three-dimensional imaging system is simple and ingeniously designed, and the three-dimensional imaging method based on it achieves three-dimensional imaging of the object under test, making the three-dimensional imaging process much simpler.

[0024] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0025] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure, and are not intended to unduly limit this disclosure.

[0026] Figure 1 This is a schematic diagram illustrating a three-dimensional imaging system according to an exemplary embodiment;

[0027] Figure 2 This is a flowchart illustrating a three-dimensional imaging method according to an exemplary embodiment;

[0028] Figure 3 This is a flowchart illustrating another three-dimensional imaging method according to an exemplary embodiment;

[0029] Figure 4 This is a flowchart illustrating another three-dimensional imaging method according to an exemplary embodiment;

[0030] Figure 5 This is a block diagram of a three-dimensional imaging device according to an exemplary embodiment;

[0031] Figure 6 This is a block diagram illustrating an electronic device for three-dimensional imaging according to an exemplary embodiment. Detailed Implementation

[0032] To enable those skilled in the art to better understand the technical solutions of this disclosure, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings.

[0033] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this disclosure described herein can be implemented in orders other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0034] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for display, data used for analysis, etc.) involved in this disclosure are all information and data authorized by the user or fully authorized by all parties.

[0035] Please see Figure 1 , Figure 1 This is a schematic diagram of a three-dimensional imaging system according to an exemplary embodiment. The system may include a camera 10, a first set of reflectors 20 (including a first reflector 21 and a second reflector 22), a second set of reflectors 30 (including a third reflector 31 and a fourth reflector 32), and a three-dimensional imaging module 40.

[0036] In an optional embodiment, the camera 10 faces the object to be tested. Specifically, the camera 10 can be a camera capable of acquiring a two-dimensional image of the object to be tested. Specifically, a camera capable of acquiring a two-dimensional image of the object to be tested can include a color camera, a black-and-white camera, a CCD camera, and a CMOS camera, etc. The reflecting surfaces of the first set of reflectors 20 face the object to be tested. Specifically, the first set of reflectors 20 can be used to reflect incident light from the object to be tested onto a second set of reflectors, and determine a first virtual optical center and a second virtual optical center based on the extension line of the incident light passing through the first set of reflectors. Specifically, the first set of reflectors 20 can be a plane mirror. The second set of reflectors 30 is located inside the first set of reflectors. Specifically, the second set of reflectors 30 can be used to reflect the first... The incident light reflected by the set of reflectors 20 is reflected onto the camera 10, so that the camera 10 can acquire a two-dimensional image of the object under test. Specifically, the second set of reflectors 30 can be a plane mirror. The three-dimensional imaging module 40 can be used to perform three-dimensional imaging processing on the two-dimensional image based on the first coordinate system, the second coordinate system, the third coordinate system, the fourth coordinate system, and the fifth coordinate system to obtain a target three-dimensional image of the object under test. Specifically, the three-dimensional imaging module can include a parameter calibration device, an image processing device, and a three-dimensional imaging display device. Specifically, the parameter calibration device can be used to calibrate the parameters corresponding to the three-dimensional imaging system, the image processing device can be used to process the two-dimensional image of the object under test acquired by the camera and generate a three-dimensional image of the object under test, and the three-dimensional imaging display device can be used to display the three-dimensional image of the object under test.

[0037] In one specific embodiment, the first coordinate system is a two-dimensional coordinate system with the first virtual optical center as the origin; the second coordinate system is a three-dimensional coordinate system with the first virtual optical center as the origin; the third coordinate system is a two-dimensional coordinate system with the second virtual optical center as the origin; the fourth coordinate system is a three-dimensional coordinate system with the second virtual optical center as the origin; and the fifth coordinate system is a three-dimensional coordinate system with the midpoint of the line connecting the first virtual optical center and the second virtual optical center as the origin.

[0038] In an optional embodiment, the first set of reflectors 20 is at a first preset distance from the camera 10. Specifically, the first preset distance is a distance that the first set of reflectors can reflect the incident light from the object to be measured to the second set of reflectors. Specifically, this distance can be a distance set in advance by the user, for example, 0.5 meters.

[0039] In one specific embodiment, the first set of reflectors 20 includes a first reflector 21 and a second reflector 22 arranged symmetrically about the optical axis of the lens of the camera 10. Specifically, the reflecting surfaces of the first reflector 21 and the second reflector 22 both face the object to be measured. Specifically, the first reflector 21 and the second reflector 22 can be plane mirrors.

[0040] In an optional embodiment, the second set of reflectors 30 is at a second preset distance from the camera 10. Specifically, the second preset distance is a distance that the second set of reflectors can reflect the incident light from the object under test reflected by the first set of reflectors onto the camera. Specifically, this distance can be a distance set in advance by the user, such as 0.5 meters.

[0041] In one specific embodiment, the second set of reflectors 30 includes a third reflector 31 and a fourth reflector 32 arranged symmetrically about the optical axis of the lens of the camera 10. Specifically, the reflective surfaces of the third reflector 31 and the fourth reflector 32 both face the camera. Specifically, the third reflector 31 and the fourth reflector 32 can be plane mirrors.

[0042] In an optional embodiment, the camera 10 is used to provide a service of acquiring a two-dimensional image of any object under test in three-dimensional imaging, and the three-dimensional imaging module 40 is used to provide a service of performing three-dimensional imaging processing on the two-dimensional image of any object under test in three-dimensional imaging to obtain a target three-dimensional image of any object under test.

[0043] In practical applications, the camera 10 mentioned above is a camera that uses a regular lens (non-tilt-shift lens). Specifically, the camera is a camera in which the optical axes of all the lenses of the lens coincide. The three-dimensional imaging module 40 mentioned above can be, but is not limited to, electronic devices such as desktop computers, tablets, laptops, and smartphones. Optionally, the operating system running on the electronic device can be, but is not limited to, Android, iOS, Linux, Windows, etc.

[0044] In an optional embodiment, the system further includes a projector 50, which generates carrier frequency stripes and projects the carrier frequency stripes onto the object under test so that a camera can capture an image of the deformed stripes on the object under test.

[0045] In one specific embodiment, the carrier frequency stripes may include dual-frequency interference stripes, sinusoidal stripes, and orthogonal stripes, etc.; the deformed stripe image is a deformed carrier frequency stripe image generated by the height modulation of the object under test.

[0046] Accordingly, the projector 50 can use methods such as dual-frequency interference fringe projection, parallel light interference fringe projection, sinusoidal fringe projection, and Gray code-based fringe projection to generate carrier frequency fringes and project them onto the object under test. Specifically, the projector 50 can use fringe generators such as DMD, LCD, circular grating, orthogonal grating, and spatial light modulator to generate carrier frequency fringes such as dual-frequency interference fringes, sinusoidal fringes, and orthogonal fringes, and then project the carrier frequency fringes onto the surface of the object under test.

[0047] In one specific embodiment, the projector 50 faces the object to be measured and is located at the optical axis of the lens of the camera 10, at a third preset distance from the camera 10. Specifically, the third preset distance is greater than the second preset distance. The third preset distance can be a distance set by the user based on the second preset distance. For example, when the second preset distance is 0.5 meters, the user sets the third preset distance to 0.6 meters.

[0048] In the above embodiments, the three-dimensional imaging system includes a camera 10, a first set of reflectors 20, a second set of reflectors 30, and a three-dimensional imaging module 40. Multiple incident light rays from the object under test will pass through the first set of reflectors 20 and the second set of reflectors 30 in sequence, and finally reflect onto the camera 10, so that the camera 10 can acquire a two-dimensional image of the object under test. Based on the two-dimensional image and the first to fifth coordinate systems, the three-dimensional imaging module 40 can generate a target three-dimensional image of the object under test. This system is a monocular to binocular stereo vision system with a compact structure and ingenious design. Only one camera is needed to realize the subsequent three-dimensional imaging method through this system, thereby completing the three-dimensional imaging of the object under test. At the same time, the system can be equipped with a projector 50, which is convenient for combining the fringe projection method to realize the three-dimensional imaging of the object under test.

[0049] In addition, it should be noted that, Figure 1 The system shown is merely one type of three-dimensional imaging system provided in this disclosure. In practical applications, it may include other devices, such as more projectors.

[0050] In the embodiments described in this specification, the camera 10 and the three-dimensional imaging module 40 can be directly or indirectly connected via wired or wireless communication, and this disclosure does not impose any restrictions.

[0051] The following describes an embodiment of a three-dimensional imaging method based on the above-mentioned three-dimensional imaging system, such as... Figure 2 As shown, Figure 2This is a flowchart illustrating a three-dimensional imaging method according to an exemplary embodiment, the method including the following steps:

[0052] In step S201, the incident light from the object under test is reflected onto the second set of mirrors in the three-dimensional imaging system based on the first set of mirrors in the three-dimensional imaging system.

[0053] In a specific embodiment, the first set of reflectors includes a first reflector and a second reflector. The method can be as follows: when the object to be tested is within the effective field of view of the camera, specifically, when the object to be tested is within the maximum range that the camera can observe, multiple incident light rays from the object to be tested are respectively injected into the first reflector and the second reflector, and the multiple incident light rays are respectively reflected by the first reflector and the second reflector to the second set of reflectors.

[0054] In step S203, the incident light rays from the object under test reflected by the first set of reflectors are reflected onto the camera in the three-dimensional imaging system based on the second set of reflectors, so that the camera can acquire a two-dimensional image of the object under test.

[0055] In a specific embodiment, the second set of reflectors includes a third reflector and a fourth reflector. The method can be as follows: multiple incident rays from the object under test are reflected by the first and second reflectors to the third and fourth reflectors, respectively. The third and fourth reflectors reflect the incident rays from the object under test reflected by the first and second reflectors onto a camera in a three-dimensional imaging system, so that the camera can acquire a two-dimensional image of the object under test. Specifically, the third reflector reflects the incident rays from the object under test reflected by the first reflector onto the camera in the three-dimensional imaging system, while the fourth reflector reflects the incident rays from the object under test reflected by the second reflector onto the camera in the three-dimensional imaging system, so that the camera can acquire a two-dimensional image of the object under test.

[0056] In the above embodiments, the incident light rays from the object under test are reflected onto the second set of mirrors in the 3D imaging system based on the first set of mirrors; and the incident light rays from the first set of mirrors are reflected onto the camera in the 3D imaging system based on the second set of mirrors. By making the incident light rays from the object under test undergo two reflections before entering the camera, it is ensured that the camera can acquire a two-dimensional image formed after the incident light rays from the object under test undergo two reflections, which facilitates subsequent processing of the two-dimensional image to generate a three-dimensional image of the object under test.

[0057] In step S205, the first virtual optical center and the second virtual optical center are determined based on the extension of the incident light rays passing through the first set of reflectors.

[0058] In a specific embodiment, the first virtual optical center and the second virtual optical center can be regarded as the optical centers of two virtual cameras. The method can be as follows: when at least two non-parallel incident rays from the object under test are incident on the first reflector, the extension lines of the multiple incident rays are drawn respectively, and the intersection of the extension lines of the multiple incident rays is obtained. This intersection is the first virtual optical center. At the same time, when at least two non-parallel incident rays from the object under test are incident on the second reflector, the extension lines of the multiple incident rays are drawn respectively, and the intersection of the extension lines of the multiple incident rays is obtained. This intersection is the second virtual optical center.

[0059] In one specific embodiment, the above method further includes:

[0060] A first virtual camera is established based on the first virtual optical center;

[0061] A second virtual camera is established based on the second virtual optical center.

[0062] In a specific embodiment, the first and second virtual cameras mentioned above can be used to determine the parameters corresponding to the three-dimensional imaging system. By establishing two virtual cameras, a stereoscopic vision measurement method can be realized to convert monocular (real camera) to binocular (two virtual cameras). Based on the parameters corresponding to the three-dimensional imaging system, the three-dimensional coordinates corresponding to the object under test can be calculated according to the binocular stereoscopic vision measurement method, and then three-dimensional imaging can be performed based on the three-dimensional coordinates corresponding to the object under test.

[0063] In the above embodiments, the first virtual optical center and the second virtual optical center are determined based on the extension line of the incident light. Based on the first virtual optical center and the second virtual optical center, a first virtual camera and a second virtual camera can be established, so that the two-dimensional image acquired by the camera can be analyzed as a two-dimensional image obtained by the two virtual cameras. This realizes the conversion of monocular (real camera) to binocular (two virtual cameras) stereo vision measurement, thereby simplifying the process of the binocular stereo vision method and making the calculation simpler.

[0064] In step S207, based on the first coordinate system, the second coordinate system, the third coordinate system, the fourth coordinate system and the fifth coordinate system, the two-dimensional image is processed into a three-dimensional image of the object to be measured.

[0065] In a specific embodiment, the first coordinate system is a two-dimensional coordinate system with the first virtual optical center as its origin. Specifically, the first coordinate system is an image physical coordinate system established based on the first virtual camera corresponding to the first virtual optical center, used to represent the projection position of the three-dimensional point of the object under test on the image plane. The x-axis is parallel to the image plane and points horizontally to the right, and the y-axis is perpendicular to the x-axis and points downwards. The second coordinate system is a three-dimensional coordinate system with the first virtual optical center as its origin. Specifically, the second coordinate system is a camera coordinate system of a binocular system established based on the first virtual camera corresponding to the first virtual optical center. The x and y axes are parallel to the x and y axes of the image coordinate system, the optical axis of the first virtual camera is the z-axis, and the coordinate system satisfies the right-hand rule. The third coordinate system is a two-dimensional coordinate system with the second virtual optical center as its origin. The third coordinate system is the image physical coordinate system established based on the second virtual camera corresponding to the second virtual optical center. The x-axis is parallel to the image plane and points horizontally to the right, while the y-axis is perpendicular to the x-axis and points downwards. The fourth coordinate system is a three-dimensional coordinate system with the second virtual optical center as its origin. Specifically, the fourth coordinate system is the camera coordinate system of the binocular system established based on the second virtual camera corresponding to the second virtual optical center. The x and y axes are parallel to the x and y axes of the image coordinate system, and the optical axis of the second virtual camera is the z-axis. The coordinate system satisfies the right-hand rule. The fifth coordinate system is a three-dimensional coordinate system with the midpoint of the line connecting the first and second virtual optical centers as its origin. This midpoint is located on the optical axis of the real camera. The fifth coordinate system is the world coordinate system of the object under test, used to characterize the position of the object under test in real three-dimensional space.

[0066] In a specific embodiment, such as Figure 3 As shown, the above-mentioned three-dimensional imaging processing of a two-dimensional image based on the first coordinate system, the second coordinate system, the third coordinate system, the fourth coordinate system, and the fifth coordinate system yields the target three-dimensional image of the object under test, including:

[0067] In step S2071, based on the two-dimensional image, the first coordinates of the object under test in the first coordinate system and the third coordinates of the object under test in the third coordinate system are determined;

[0068] In step S2073, based on the first coordinate and the third coordinate, the second coordinate of the object to be measured in the second coordinate system and the fourth coordinate of the object to be measured in the fourth coordinate system are determined;

[0069] In step S2075, the visual structure parameters corresponding to the three-dimensional imaging system are determined;

[0070] In step S2077, target mapping information is established based on the second coordinate and the fourth coordinate. The target mapping information represents the correspondence between visual structural parameters and the fifth coordinate of the object under test in the fifth coordinate system.

[0071] In step S2079, the fifth coordinate is determined based on the target mapping information and visual structure parameters;

[0072] In step S2081, a three-dimensional image of the target is generated based on the fifth coordinate.

[0073] In a specific embodiment, the above-mentioned determination of the first coordinates of the object under test in a first coordinate system and the third coordinates of the object under test in a third coordinate system based on a two-dimensional image, wherein the first coordinates are image physical coordinates determined based on a first virtual camera, and the third coordinates are image physical coordinates determined based on a second virtual camera, including:

[0074] The first coordinate of the object to be measured in the first coordinate system is determined to be (X1, Y1);

[0075] The third coordinate of the object to be measured in the third coordinate system is determined to be (X2, Y2).

[0076] In a specific embodiment, determining the second coordinate of the object under test in the second coordinate system and the fourth coordinate of the object under test in the fourth coordinate system based on the first and third coordinates includes:

[0077] Based on the principle of the camera's linear perspective model, a first mapping information is established based on the first coordinate system. The first mapping information represents the mapping relationship between the first coordinate system and the second coordinate system.

[0078] Based on the first coordinate and the mapping relationship between the first coordinate system and the second coordinate system, the second coordinate of the object to be measured in the second coordinate system is determined to be (x1, y1, z1).

[0079] Based on the third coordinate system, a second mapping information is established, which represents the correspondence between the third coordinate system and the fourth coordinate system.

[0080] Based on the third coordinate and the mapping relationship between the third and fourth coordinate systems, the fourth coordinate of the object to be measured in the fourth coordinate system is determined to be (x2, y2, z2).

[0081] In a specific embodiment, the mapping relationship between the first coordinate system and the second coordinate system can be expressed as M1 = Px c1 Where M1 = (X1, Y1, 1) T x c1 = (x1, y1, z1, 1) T P is the camera's intrinsic parameter. f is the focal length of the camera; the mapping relationship between the third and fourth coordinate systems can be expressed as M2 = Px c2 Where M2 = (X2, Y2, 1) T x c2 = (x², y², z², 1) T .

[0082] In a specific embodiment, the visual structure parameters corresponding to the above-mentioned three-dimensional imaging system include: baseline length, first distance, second distance, depth of the effective field of view corresponding to the camera, horizontal width of the effective field of view corresponding to the camera, third distance, first included angle, second included angle, third included angle and fourth included angle;

[0083] Specifically, the baseline length is the distance between the first virtual optical center and the second virtual optical center; the first distance is the distance between the optical center of the camera and the second set of reflectors; the second distance is the horizontal distance between the first set of reflectors and the second set of reflectors; the third distance is the closest distance between the effective field of view and the second set of reflectors; the first included angle is the angle between the first set of reflectors and the x-axis in the fifth coordinate system; the second included angle is the angle between the second set of reflectors and the x-axis in the fifth coordinate system; the third included angle is the angle between any optical axis of the two virtual cameras and the x-axis in the fifth coordinate system; and the fourth included angle is the angle between any optical axis of the two virtual cameras and the corresponding image plane of the object under test.

[0084] In one specific embodiment, determining the visual structural parameters corresponding to the three-dimensional imaging system includes:

[0085] Based on a three-dimensional imaging system, the baseline length, first distance, second distance, first included angle, second included angle, third included angle, and fourth included angle are measured.

[0086] The third distance is determined based on the geometric relationships of the baseline length, the first distance, the second distance, the first included angle, the second included angle, the third included angle, and the fourth included angle;

[0087] Based on the geometric relationships of baseline length, first distance, second distance, third distance, first included angle, second included angle, third included angle, and fourth included angle, the depth of the effective field of view corresponding to the camera is determined, and the horizontal width of the effective field of view corresponding to the camera is determined.

[0088] In one specific embodiment, determining the third distance includes:

[0089] Define h as the first distance, d as the second distance, h0 as the third distance, β as the first included angle, α as the second included angle, θ as the third included angle, γ as the fourth included angle, and L as half the baseline length;

[0090] Based on the three-dimensional imaging system, and according to the principles of geometric optics, we can obtain:

[0091]

[0092] (2) L=hsin(β-α)+2dsin 2 β

[0093] Based on equations (1) and (2) and the geometric relationships in the three-dimensional imaging system, the third distance h0 can be obtained:

[0094] (3) h0=Ltanθ-|hsinθ+2d sin 2 β|

[0095] In one specific embodiment, determining the depth of the effective field of view corresponding to the camera and determining the horizontal width of the effective field of view corresponding to the camera include:

[0096] Based on equations (1), (2), and (3), the depth Δh and horizontal width W of the effective field of view can be obtained:

[0097]

[0098]

[0099] In a specific embodiment, the target mapping information described above can characterize the correspondence between visual structural parameters and the fifth coordinate of the object under test in the fifth coordinate system; the establishment of target mapping information based on the second and fourth coordinates may include:

[0100] Based on the second coordinate, establish the first mapping information;

[0101] Based on the fourth coordinate, establish the second mapping information;

[0102] Based on the first mapping information and the second mapping information, the target mapping information is obtained.

[0103] Specifically, based on the principle of rigid body transformation, the camera coordinate system represented by the second and fourth coordinate systems can be transformed into the world coordinate system represented by the fifth coordinate system through a rotation matrix. Specifically, the aforementioned first mapping information can represent the mapping relationship between the second and fifth coordinate systems. Correspondingly, the first mapping information can be expressed as... Where (x, y, z) are the fifth coordinates of the object to be measured, and θ is the angle of the third included angle; the above-mentioned second mapping information can characterize the mapping relationship between the fourth coordinate system and the fifth coordinate system. Specifically, the second mapping information can be expressed as follows: Where L is half the baseline length, (x, y, z) is the fifth coordinate of the object to be measured, and θ is the angle of the third included angle.

[0104] In a specific embodiment, based on the above-mentioned second coordinate, fourth coordinate, first mapping information, and second mapping information, the fifth coordinate (x, y, z) can be derived by combining equations (1) and (2):

[0105]

[0106]

[0107]

[0108] Where α is the first included angle, β is the second included angle, h is the first distance, and d is the second distance.

[0109] In one specific embodiment, generating a target 3D image based on the fifth coordinate includes:

[0110] Based on the fifth coordinate, obtain the three-dimensional information of the object under test;

[0111] Reconstruct the three-dimensional contour of the object under test based on its three-dimensional information.

[0112] Generate a 3D image of the target based on the 3D contour.

[0113] The three-dimensional contour of the object under test can be reconstructed using three-dimensional reconstruction software such as SfM (Structure from Motion), MVE (Multi-View Environment), and SR (Surface Reconstruction) based on the three-dimensional information of the object under test.

[0114] In the above embodiments, a three-dimensional image of the object under test is generated based on a two-dimensional image and first to fifth coordinate systems. Specifically, the first and third coordinates of the two-dimensional image are used as the basis for determining the second and fourth coordinates of the object under test, thereby determining the visual structural parameters corresponding to the three-dimensional imaging system. Based on the second and fourth coordinates, target mapping information is established, and this target mapping information characterizes the visual structural parameters and the fifth coordinate of the object under test. Finally, a three-dimensional image of the target is generated based on the fifth coordinate (the three-dimensional coordinates of the object under test). This method allows for the determination of the mapping relationship between coordinate systems based on the principle of binocular stereoscopic imaging when performing three-dimensional imaging of the object under test. It also simplifies the measurement process of traditional binocular stereoscopic imaging, making the calculation of the three-dimensional coordinates of the object under test much simpler.

[0115] In an optional embodiment, before determining the visual structural parameters corresponding to the three-dimensional imaging system, the method further includes:

[0116] The camera acquires images of deformed stripes on the object under test;

[0117] Based on the deformed stripe image, the intrinsic parameters of the camera are determined.

[0118] In one specific embodiment, the aforementioned deformed fringe image is a carrier frequency fringe image deformed by the high modulation of the object under test; the determination of the camera's intrinsic parameters based on the deformed fringe image includes: determining the intrinsic parameter P matrix based on the deformed fringe image, specifically, the P matrix can be represented as... f is the focal length of the camera. Therefore, the P matrix in the intrinsic parameters determined based on the deformed fringe image can be: Determine the value of the camera's focal length f based on the deformed fringe image.

[0119] In an optional embodiment, determining the second coordinate of the object under test in the second coordinate system and the fourth coordinate of the object under test in the fourth coordinate system based on the first and third coordinates includes:

[0120] Based on the first coordinate, the third coordinate, and the camera's intrinsic parameters determined from the deformed fringe image, the second coordinate of the object under test in the second coordinate system and the fourth coordinate of the object under test in the fourth coordinate system are determined.

[0121] In the above embodiments, a deformed fringe image on the object under test is obtained by projecting carrier frequency fringes through a projector; based on the deformed fringe image, the intrinsic parameters of the camera are determined. That is, the intrinsic parameters of the camera are determined by the fringe projection method, which can realize the real-time correction of the camera's intrinsic parameters and prevent changes in the intrinsic parameters of the three-dimensional imaging system caused by external factors such as the usage environment and usage time. This reduces the error in the three-dimensional coordinate measurement process and makes the three-dimensional imaging of the object under test more accurate.

[0122] In an optional embodiment, such as Figure 4 As shown, the above method also includes:

[0123] In step S209, reference position information is obtained based on the target 3D image;

[0124] In step S211, based on the reference position information, the projector projects carrier frequency stripes onto the object under test;

[0125] In step S213, the camera acquires an image of the deformed stripes on the object under test;

[0126] In step S215, phase shift information of the object under test is generated based on the deformed fringe image;

[0127] In step S217, three-dimensional imaging processing is performed based on the phase shift information to obtain a corrected three-dimensional image of the object under test.

[0128] In an optional embodiment, the aforementioned carrier frequency stripes can be sinusoidal stripes, the deformed stripe image is a carrier frequency stripe image deformed after being highly modulated by the object under test, and the aforementioned reference position information can be the three-dimensional position information of the object under test generated based on the target three-dimensional image. After obtaining the target three-dimensional image through a monocular to binocular three-dimensional imaging method, the three-dimensional position information of the object under test can be obtained. Based on this three-dimensional position information, three-dimensional imaging can be performed again using the fringe projection measurement method, which can more accurately correct the three-dimensional image as the final result compared to the target three-dimensional image.

[0129] In a specific embodiment, the above-mentioned generation of phase shift information of the test object based on the deformed fringe image includes: processing the deformed fringe image based on phase unwrapping technology to obtain a processing result; and generating phase shift information of the test object based on the processing result. Specifically, the phase shift information may include multiple phase images.

[0130] In a specific embodiment, the above-mentioned three-dimensional imaging processing based on phase shift information to obtain a corrected three-dimensional image of the object under test includes: obtaining the three-dimensional information of the object under test based on the phase shift information using the fringe projection method in structured light three-dimensional imaging technology; and performing three-dimensional imaging processing based on the three-dimensional information of the object under test to obtain a corrected three-dimensional image of the object under test. Taking the projection of sinusoidal fringes as carrier frequency fringes onto the object under test as a sinusoidal grating pattern through a projector as an example, the principle of the fringe projection method is described in detail below:

[0131] When a sinusoidal fringe image is projected onto the surface of a three-dimensional diffuse object (the object under test), the deformed fringe image obtained from the imaging system can be represented as:

[0132] I(x,y)=R(x,y){C[0.5+0.5cosφ(x,y)]}

[0133] In the formula, I(x,y) represents the light intensity received by the camera, R(x,y) represents the anisotropic reflectivity of the surface of the object under test, C represents the background light intensity, and the phase function Φ(x,y) represents the phase of the deformed fringes. When the object under test is a standard plane (reference plane), the phase of the deformed fringes has a linear distribution.

[0134]

[0135] In the formula, Po is the period of the fringes on the reference plane. When the object under test is a three-dimensional surface distributed on h(x,y), the imaging process of the object under test adds additional phase modulation caused by height, and Φ(x,y) can be expressed as:

[0136]

[0137] In the formula, λe is the equivalent wavelength. One equivalent wavelength causes a phase change of 2π. In this case, the deformed fringe image acquired by the imaging system can be expressed as:

[0138]

[0139] Because the height change of the surface of the object under test causes the fringe phase change, the camera acquires a deformed fringe image. By using phase shifting technology, Φ(x,y) can be separated from multiple frames of phase shifted fringe images (i.e. deformed fringe images). Furthermore, by using phase shifting technology, R(x,y) can be separated from the modulation of the fringe, and the distribution of the object under test on the three-dimensional surface of h(x,y) can be reconstructed, thus obtaining the three-dimensional information of the object under test.

[0140] In the above embodiments, after obtaining the target three-dimensional image, the three-dimensional position information of the object to be measured can be obtained. Based on this three-dimensional position information, three-dimensional imaging is performed again using the fringe projection measurement method. The fringe projection measurement method itself is affected by the fringe period and has a limited measurement range. According to the embodiments of the present invention, this method can combine the already obtained target three-dimensional image to perform three-dimensional imaging again, so as to obtain a more accurate corrected three-dimensional image as the final result. While ensuring a larger measurement range, it can effectively reduce the error in the three-dimensional imaging process, thereby enabling the user to obtain a more accurate three-dimensional image, and thus obtain clearer shape and position information about the object to be measured.

[0141] Figure 5 This is a block diagram illustrating a three-dimensional imaging device according to an exemplary embodiment. (Refer to...) Figure 5 The device includes:

[0142] The first reflection module 510 is used to reflect incident light from the object under test onto the second set of mirrors in the three-dimensional imaging system, based on the first set of mirrors in the three-dimensional imaging system.

[0143] The second reflection module 520 is used to reflect the incident light from the first set of reflectors onto the camera in the three-dimensional imaging system based on the second set of reflectors, so that the camera can acquire a two-dimensional image of the object under test.

[0144] The virtual optical center determination module 530 determines the first virtual optical center and the second virtual optical center based on the extension of the incident light ray;

[0145] The target 3D image acquisition module 540 is used to perform 3D imaging processing on a 2D image based on a first coordinate system, a second coordinate system, a third coordinate system, a fourth coordinate system, and a fifth coordinate system to obtain a target 3D image of the object to be measured.

[0146] In an optional embodiment, the target 3D image acquisition module 440 includes:

[0147] The parameter calibration module is used to calibrate the parameters corresponding to the three-dimensional imaging system.

[0148] The image processing module is used to process the two-dimensional image of the object to be tested acquired by the camera and generate a three-dimensional image of the object to be tested;

[0149] The 3D image display module is used to display the target 3D image of the object under test, obtained by performing 3D imaging processing on a 2D image.

[0150] In an optional embodiment, the parameter calibration module includes:

[0151] Camera intrinsic parameter calibration unit, used to calibrate the intrinsic parameters of the camera in a 3D imaging system;

[0152] The visual structure parameter calibration unit is used to calibrate the visual structure parameters of a 3D imaging system.

[0153] In an optional embodiment, the image processing module described above includes:

[0154] A two-dimensional image processing unit is used to process two-dimensional images of the object to be measured acquired by the camera;

[0155] The three-dimensional image generation unit is used to generate a three-dimensional image of the object under test based on the two-dimensional image of the object under test processed by the two-dimensional image processing unit.

[0156] In an optional embodiment, the above-mentioned three-dimensional image display module further includes:

[0157] The calibration 3D image display unit is used to display the calibration 3D image of the object under test obtained after 3D imaging processing based on phase shift information.

[0158] The calibrated 3D image display unit is used to display the calibrated 3D image obtained after the target 3D image has been calibrated based on the calibrated 3D image.

[0159] Regarding the apparatus in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0160] Figure 6 This is a block diagram illustrating an electronic device for three-dimensional imaging according to an exemplary embodiment. The electronic device may be a three-dimensional imaging module, and its internal structure diagram may be as follows: Figure 6As shown, the electronic device includes a processor, memory, network interface, display screen, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage medium. The network interface is used to communicate with external terminals via a network connection. When the computer program is executed by the processor, it implements a three-dimensional imaging method. The display screen can be a liquid crystal display (LCD) or an e-ink display. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad mounted on the device's casing, or an external keyboard, touchpad, or mouse.

[0161] Those skilled in the art will understand that Figure 6 The structure shown is merely a block diagram of a portion of the structure related to the present disclosure and does not constitute a limitation on the electronic device to which the present disclosure is applied. A specific electronic device may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0162] In an exemplary embodiment, an electronic device is also provided, including: a processor; and a memory for storing processor-executable instructions; wherein the processor is configured to execute the instructions to implement the three-dimensional imaging method as described in the embodiments of this disclosure.

[0163] In an exemplary embodiment, a computer-readable storage medium is also provided, wherein instructions in the storage medium, when executed by a processor of an electronic device, enable the electronic device to perform the three-dimensional imaging method of the present disclosure embodiments.

[0164] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. This computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.

[0165] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the following claims.

[0166] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. A three-dimensional imaging system, characterized in that, The system includes: Camera, first set of reflectors, second set of reflectors, and 3D imaging module; The reflecting surfaces of the first set of mirrors face the object to be tested; the first set of mirrors is used to reflect the incident light rays from the object to be tested onto the second set of mirrors, and to determine the first virtual optical center and the second virtual optical center based on the extension of the incident light rays; The second set of reflectors is located inside the first set of reflectors; the second set of reflectors is used to reflect the incident light reflected by the first set of reflectors onto the camera, so that the camera can acquire a two-dimensional image of the object under test; The first set of reflectors is at a first preset distance from the camera. The first set of reflectors includes a first reflector and a second reflector that are symmetrical about the optical axis of the camera lens. The reflective surfaces of both the first reflector and the second reflector face the object to be tested. The second set of reflectors is at a second preset distance from the camera; the second set of reflectors is provided with a third reflector and a fourth reflector that are symmetrical about the optical axis of the camera lens; the reflective surfaces of the third reflector and the fourth reflector both face the camera; The three-dimensional imaging module is used to perform three-dimensional imaging processing on the two-dimensional image based on a first coordinate system, a second coordinate system, a third coordinate system, a fourth coordinate system, and a fifth coordinate system to obtain a target three-dimensional image of the object under test; the first coordinate system is a two-dimensional coordinate system with the first virtual optical center as the origin; the second coordinate system is a three-dimensional coordinate system with the first virtual optical center as the origin; the third coordinate system is a two-dimensional coordinate system with the second virtual optical center as the origin; the fourth coordinate system is a three-dimensional coordinate system with the second virtual optical center as the origin; and the fifth coordinate system is a three-dimensional coordinate system with the midpoint of the line connecting the first virtual optical center and the second virtual optical center as the origin.

2. The three-dimensional imaging system according to claim 1, characterized in that, The system also includes: A projector is positioned facing the object under test and located on the optical axis of the camera lens, at a third preset distance from the camera, the third preset distance being greater than a second preset distance; the projector is used to generate carrier frequency stripes and project the carrier frequency stripes onto the object under test, so that the camera can acquire a deformed stripe image on the object under test.

3. A three-dimensional imaging method based on the three-dimensional imaging system as described in claim 1 or 2, characterized in that, The method includes: Based on the first set of mirrors in the three-dimensional imaging system, the incident light from the object under test is reflected onto the second set of mirrors in the three-dimensional imaging system; The incident light reflected by the first set of reflectors is reflected by the second set of reflectors onto the camera in the three-dimensional imaging system, so that the camera can acquire a two-dimensional image of the object under test. The first virtual optical center and the second virtual optical center are determined based on the extension of the incident light rays passing through the first set of reflectors; Based on the first coordinate system, the second coordinate system, the third coordinate system, the fourth coordinate system, and the fifth coordinate system, the two-dimensional image is subjected to three-dimensional imaging processing to obtain the target three-dimensional image of the object under test; Wherein, the first coordinate system is a two-dimensional coordinate system with the first virtual optical center as the origin; the second coordinate system is a three-dimensional coordinate system with the first virtual optical center as the origin; the third coordinate system is a two-dimensional coordinate system with the second virtual optical center as the origin; the fourth coordinate system is a three-dimensional coordinate system with the second virtual optical center as the origin; and the fifth coordinate system is a three-dimensional coordinate system with the midpoint of the line connecting the first virtual optical center and the second virtual optical center as the origin.

4. The method according to claim 3, characterized in that, The step of performing three-dimensional imaging processing on the two-dimensional image based on the first coordinate system, the second coordinate system, the third coordinate system, and the fourth coordinate system to obtain the target three-dimensional image of the object under test includes: Based on the two-dimensional image, determine the first coordinate of the object under test in the first coordinate system and the third coordinate of the object under test in the third coordinate system; Based on the first coordinate and the third coordinate, determine the second coordinate of the object under test in the second coordinate system and the fourth coordinate of the object under test in the fourth coordinate system; Determine the visual structure parameters corresponding to the three-dimensional imaging system; Based on the second coordinate and the fourth coordinate, target mapping information is established, wherein the target mapping information characterizes the correspondence between the visual structural parameters and the fifth coordinate of the object under test in the fifth coordinate system; The fifth coordinate is determined based on the target mapping information and the visual structure parameters; The target 3D image is generated based on the fifth coordinate.

5. The method according to claim 4, characterized in that, The step of determining the second coordinate of the object under test in the second coordinate system and the fourth coordinate of the object under test in the fourth coordinate system based on the first coordinate and the third coordinate includes: Based on the first coordinates, a first mapping information is established, which represents the correspondence between the first coordinate system and the second coordinate system. The second coordinate is determined based on the first coordinate and the first mapping information; Based on the third coordinate, a second mapping information is established, which represents the correspondence between the third coordinate system and the fourth coordinate system; The fourth coordinate is determined based on the third coordinate and the second mapping information.

6. The method according to claim 4, characterized in that, Before determining the visual structural parameters corresponding to the three-dimensional imaging system, the method further includes: Acquire the deformed stripe image on the test object; Based on the deformed stripe image, the intrinsic parameters of the camera are determined.

7. The method according to claim 6, characterized in that, The step of determining the second coordinate of the object under test in the second coordinate system and the fourth coordinate of the object under test in the fourth coordinate system based on the first coordinate and the third coordinate includes: Based on the first coordinate, the third coordinate, and the intrinsic parameter, the second coordinate of the object under test in the second coordinate system and the fourth coordinate of the object under test in the fourth coordinate system are determined.

8. The method according to claim 3, characterized in that, The method further includes: Based on the target 3D image, obtain reference position information; Based on the reference position information, the projector projects carrier frequency stripes onto the object under test; The camera acquires images of deformed stripes on the object under test; Based on the deformed stripe image, the phase shift information of the object under test is generated; Based on the phase shift information, three-dimensional imaging processing is performed to obtain a corrected three-dimensional image of the object under test.

9. The method according to any one of claims 4-7, characterized in that, The visual structure parameters include: baseline length, first distance, second distance, depth of the effective field of view corresponding to the camera, horizontal width of the effective field of view corresponding to the camera, third distance, first included angle, second included angle, third included angle, and fourth included angle; the determination of the visual structure parameters corresponding to the three-dimensional imaging system includes: Measure the baseline length, the first distance, the second distance, the first included angle, the second included angle, the third included angle, and the fourth included angle; Based on the geometric relationship between the baseline length, the first distance, and the second distance, and the geometric relationship between the first included angle, the second included angle, the third included angle, and the fourth included angle, the third distance is determined. Based on the geometric relationship between the baseline length, the first distance, the second distance, and the third distance, and the geometric relationship between the first included angle, the second included angle, the third included angle, and the fourth included angle, the depth and the horizontal width are determined. Wherein, the baseline length is the distance between the first virtual optical center and the second virtual optical center; the first distance is the distance between the optical center of the camera and the second set of reflectors; the second distance is the horizontal distance between the first set of reflectors and the second set of reflectors; the third distance is the closest distance between the effective field of view and the second set of reflectors; the first angle is the angle between the first set of reflectors and the x-axis in the fifth coordinate system; the second angle is the angle between the second set of reflectors and the x-axis in the fifth coordinate system; the third angle is the angle between the optical axis of the virtual camera and the x-axis in the fifth coordinate system; the fourth angle is the angle between the optical axis of the virtual camera and the corresponding image plane of the object under test; the virtual camera includes a first virtual camera and a second virtual camera, the first virtual camera being a camera established based on the first virtual optical center, and the second virtual camera being a camera established based on the second virtual optical center.

Images