Digital image stereomicroscopy system and method with variable baseline parallax angle

Abstract

The application discloses a variable-baseline and phase-angle photography digital image stereo microscopic system and method, which realizes the forward and reverse equal translation movement of left and right two plane array digital photography cameras when the stereo photography distance is changed, and keeps the ratio K of the stereo image model camera baseline and the photography height unchanged in the movement, solves the problems of unstable stereo image model and stereo image flattening in the existing digital image stereo microscopic technology, and keeps the large stereo field of large stereo image overlap. After the stereo image is collected through photography and shooting, the camera internal parameter correction and the space projection position and posture correction are carried out through a data processing device, the digital image is rearranged, the errors of the camera pairing manufacturing itself and the errors generated by the variable-baseline and phase-angle photography system manufacturing and installation are eliminated, the requirements for the stereo photography camera manufacturing and the system equipment manufacturing and installation are reduced, and the technical performance of the digital image stereo microscopic system is improved.

Description

Technical Field

[0001] This invention belongs to the field of digital imaging stereomicroscopy observation and detection, specifically to the fields of digital imaging stereomicroscopy for medical surgery, digital imaging stereomicroscopy for biological observation and detection, digital imaging stereomicroscopy for material observation and detection, digital imaging stereomicroscopy for process observation and detection, and digital imaging stereomicroscopy for microscopic object observation and detection. In particular, it relates to a digital imaging stereomicroscopy system and method with variable baseline phase angle photography. Background Technology

[0002] Currently, microscopes include stereoscopic optical microscopes and digital imaging stereo (3D) microscopes. Both stereoscopic optical microscopes and digital imaging stereo (3D) microscopes employ two design principles: the tilting light path stereoscopic microscope principle and the parallel light path stereoscopic microscope principle. Due to the limitations of these two principles, the observed stereoscopic visual model is distorted and unstable, affecting human perception and manipulation capabilities. The magnification of stereoscopic microscopes is limited, the resolution of stereoscopic images is low, the observation distance is limited, and the field of view is small. Due to the design principles, the manufacturing and installation techniques are extremely demanding. If the manufacturing parameters of the two cameras are not identical, or if the two cameras cannot be installed precisely and stably, it will lead to image projection distortion, resulting in vertical parallax, and causing dizziness during stereoscopic image observation.

[0003] To avoid image projection distortion, current digital imaging stereo (3D) microscope systems require that the lenses of the two cameras have the same focal length and the same physical distortion. The CCD sensors of the two cameras must be installed at the same center position and cannot be rotated. The projection of the center light from the camera lens must be at the center of the camera sensor. The two cameras must be installed in strict parallel orientation. The precision manufacturing, installation, use, and maintenance of the system are extremely demanding.

[0004] When observing stereoscopic images with varying object distances and heights, optical microscopes using the principles of tilted and parallel light paths maintain a fixed baseline distance B between the two objectives. Digital stereoscopic (3D) microscopes, on the other hand, maintain a fixed baseline distance B between the two cameras. When the observation distance H changes, the ratio of the camera mounting baseline B to the change in the photographic distance H becomes unstable, resulting in an unstable height ratio of the stereoscopic image model. Consequently, the observed stereoscopic image visual model appears to be either high or low, and the stereoscopic image becomes flattened, which can affect the user's habitual perception and operational abilities.

[0005] The tilted optical path principle of digital imaging stereo (3D) microscopes results in a distorted image due to the fixed camera mounting baseline and the intersection angle of the camera. The oblique projection of the image at the intersection angle reduces the overlap of the images, shrinks the stereoscopic field of view, limits the scaling of the stereoscopic field of view, and restricts the observation distance to a short distance.

[0006] The parallel light path principle of digital imaging stereo (3D) microscopes does not fully meet the physiological stereoscopic vision observation conditions of humans due to their optical structure and image projection. The stereoscopic vision has low clarity, large distortion of stereoscopic vision height, and flattening of stereoscopic vision. It is only suitable for close-range, non-real-time stereoscopic image visual observation.

[0007] The stereoscopic models of optical stereo microscopes and digital imaging stereo (3D) microscopes based on the principles of tilted and parallel light paths are deformed, the scale K value of the stereoscopic model is unstable, and the stereoscopic image model cannot be measured. Changing the observation distance or photographic distance of the microscope reduces the overlap between the left and right images, shrinks the field of view of the stereoscopic image, and low overlap stereoscopic images only utilize the edge parts of the image, resulting in reduced stereoscopic image resolution. Summary of the Invention

[0008] The purpose of this application is to provide a digital image stereomicroscopy system and method with variable baseline phase angle photography, which solves the problems in the prior art such as strict requirements for the manufacturing and installation of photographic equipment, small overlap of adjustment distance, instability of stereo model, flattening of stereo image, low magnification, and low resolution of stereo image.

[0009] This invention is achieved through the following technical solution:

[0010] In a first aspect, the present invention provides a digital image stereomicroscopy system for variable baseline phase angle photography, comprising a first digital array camera a, a second digital array camera b, a computer data processing device, and a stereo display.

[0011] The first digital area array camera a and the second digital area array camera b are mounted on the same sliding translation mechanism. The sliding translation mechanism is provided with a central limiting point. The first digital area array camera a and the second digital area array camera b are mirror images of each other on both sides of the central limiting point, and the distance between the first digital area array camera a and the second digital area array camera b and the central limiting point is the same. The first digital area array camera a and the second digital area array camera b use the same model and have the same lens focal length f. The focal lengths of the first digital area array camera a and the second digital area array camera b are fixed, and the overlap of the images captured by the first digital area array camera a and the second digital area array camera b is kept greater than a set threshold c.

[0012] The first digital array camera a and the second digital array camera b simultaneously capture digital images, respectively obtaining a first digital image and a second digital image, and then transmitting both the first and second captured digital images to a computer data processing device.

[0013] The computer data processing device is used to perform intrinsic parameter correction and spatial projection position and attitude correction on the first and second photographic digital images, rearrange the digital images to obtain a digital image with correct spatial projection attitude, and transmit the digital image with correct spatial projection attitude to the stereoscopic display.

[0014] The stereo display is used to display stereo images or video stereo images of the photographed object based on the correct digital images of the spatial projection postures of the first digital array camera a and the second digital array camera b.

[0015] Furthermore, when the first digital area array camera a moves, the second digital area array camera b moves in the opposite direction and by the same amount as the first digital area array camera a.

[0016] Furthermore, when the distance between the first digital area array camera a and the second digital area array camera b changes, the overlap of the images captured by the first digital area array camera a and the second digital area array camera b remains greater than a set threshold c.

[0017] Before and after the adjustment, the ratio K between the baseline distance B and the shooting distance H between the two digital area array cameras remains unchanged. The baseline distance B represents the length of the line connecting the two digital area array cameras, and the shooting distance H represents the distance between the baseline and the object to be photographed.

[0018] Furthermore, the positional parameters between the first digital area array camera a and the second digital area array camera b are set as follows:

[0019] K=B1 / H1=B2 / H2=……Bn / Hn

[0020] Δa1b1M1∽Δa2b2M2∽……ΔanbnMn

[0021] ∠a1M1b1=∠a2M2b2=……∠anMnbn

[0022] ∠Ra=∠Rb

[0023] H1≠H2≠……Hn

[0024] B1≠B2≠……Bn

[0025] Wherein, B1 represents the baseline distance between the first digital area array camera a and the second digital area array camera b at the first position, and H1 represents the shooting distance at the first position; B2 represents the baseline distance between the first digital area array camera a and the second digital area array camera b at the second position, and H2 represents the shooting distance at the second position; Bn represents the baseline distance between the first digital area array camera a and the second digital area array camera b at the nth position, and Hn represents the shooting distance at the nth position; Δa1b1M1 represents the triangle formed by the point a1 of the first digital area array camera, the point b1 of the second digital area array camera, and the position M1 of the photographed object, ∽ indicates that the two triangles are similar triangles; Δa2b2M2 represents the triangle formed by the point a2 of the first digital area array camera, the point b2 of the second digital area array camera, and the position M2 of the photographed object. The triangle ΔanbnMn represents the triangle formed by the location of the first digital area array camera (an), the location of the second digital area array camera (bn), and the position of the photographed object (Mn); ∠a1M1b1 represents the angle formed by the location of the first digital area array camera (a1), the position of the photographed object (M1), and the location of the second digital area array camera (b1); ∠a2M2b2 represents the angle formed by the location of the first digital area array camera (a1), the position of the photographed object (M2), and the location of the second digital area array camera (b1); ∠anMnbn represents the angle formed by the location of the first digital area array camera (a1), the position of the photographed object (Mn), and the location of the second digital area array camera (b1); ∠Ra represents the angle between the shooting direction of the first digital area array camera (a) and the baseline B; and ∠Rb represents the angle between the shooting direction of the second digital area array camera (b) and the baseline B.

[0026] Furthermore, the mounting angle ∠Ra of the first digital area array camera a and the mounting angle ∠Rb of the second digital area array camera b are both set to a range of 1°-15°.

[0027] Furthermore, the threshold c corresponding to the overlap of the images captured by the first digital area array camera a and the second digital area array camera b is set to be greater than 90%.

[0028] In a second aspect, the present invention provides a digital image stereomicroscopy method based on the digital image stereomicroscopy system described in the first aspect, comprising:

[0029] A first digital image is acquired by a first digital array camera a, and a second digital image is acquired by a second digital array camera b.

[0030] The computer data processing device corrects the intrinsic parameters and spatial projection position and attitude of the first and second digital images to obtain a digital image with correct spatial projection attitude.

[0031] The correct spatial projection digital image is converted into stereoscopic image data by a stereoscopic display and then displayed on the stereoscopic display.

[0032] Further, intrinsic parameter correction is performed, including:

[0033] A first calibration image of the intrinsic parameter calibration board is captured by a first digital area array camera a; a second calibration image of the intrinsic parameter calibration board is captured by a second digital area array camera b, wherein the intrinsic parameter calibration board has reference calibration point coordinates.

[0034] Obtain the coordinates of the first calibration point in the first calibration image and the coordinates of the second calibration point in the second calibration image, and obtain the first intrinsic parameter correction value between the coordinates of the first calibration point and the coordinates of the reference calibration point, and obtain the second intrinsic parameter correction value between the coordinates of the second calibration point and the coordinates of the reference calibration point.

[0035] The first photographic digital image is rearranged according to the first intrinsic parameter correction value, and the second photographic digital image is rearranged according to the second intrinsic parameter correction value to eliminate image distortion caused by intrinsic parameter error.

[0036] Further, spatial projection position and attitude correction is performed, including:

[0037] An image matching algorithm is used to obtain the spatial projection position and attitude adjustment parameters of the second digital image captured by the second digital array camera b relative to the first digital image captured by the first digital array camera a.

[0038] Based on the spatial projection position and attitude adjustment parameters, the images of the first digital array camera a and the second digital array camera b are digitally rearranged to obtain the corresponding rearranged images.

[0039] Rearrange the images as correctly posed digital images in stereoscopic photographic space projection.

[0040] Furthermore, an image matching algorithm is used to obtain the spatial projection position and attitude adjustment parameters of the second digital image captured by the second digital array camera b relative to the first digital image captured by the first digital array camera a, including:

[0041] Search for multiple corresponding projection points on the first and second digital images, and based on these multiple corresponding projection points, obtain the spatial projection rotation angle and scaling correction value of the second digital image relative to the first digital image during photography, thus obtaining the spatial projection position attitude adjustment parameters.

[0042] The beneficial effects of this invention are as follows:

[0043] (1) This invention uses a calculation method to obtain the parameters of two cameras and then rearranges and corrects the images, which greatly reduces the precision manufacturing and installation requirements for pairing two cameras. It solves the problem that the original digital image stereomicroscopy principle has very high requirements for manufacturing and installation precision when pairing two cameras in a digital stereomicroscope, such as lens focal length and distortion, camera sensor installation, the correspondence between the center positions of the lens and the sensor, and the inability to be strictly identical during manufacturing.

[0044] (2) Based on the changing baseline of the two cameras in stereoscopic photography and the camera installation phase angle, the present invention obtains the correct posture correction parameters of the image space projection by computer, which reduces the requirements for precision manufacturing and installation of mechanical parts.

[0045] (3) When the stereoscopic photography distance changes, the photographic baseline changes accordingly, which can keep the ratio K coefficient of the baseline to the photographic distance constant, stabilize the stereoscopic model, maintain a large degree of stereoscopic image overlap, and overcome the phenomenon of flattening of stereoscopic image model and small field of view of stereoscopic image that occurs in long-distance stereoscopic photography, which is the original fixed baseline microscope principle method.

[0046] (4) The phase angle stereoscopic photography provided by the present invention can avoid the problem of image projection distortion caused by the flattening of the depth of field of the stereoscopic image model. The problem is solved by obtaining the correct spatial projection posture by computer and rearranging the image.

[0047] (5) The variable baseline phase angle stereo photography provided by the present invention can effectively maintain the high overlap of the images of the two cameras, increase the field of view of stereo image observation, keep the stereo model stable and undeformed, and overcome the weakness of the original stereo microscope with small field of view and unstable stereo image visual height deformation.

[0048] (6) The variable baseline phase angle stereoscopic photography provided by the present invention has a large overlap of stereoscopic images. The stereoscopic image field of view observes the high resolution of the middle part of the image and the small projection distortion, which overcomes the weaknesses of the original digital image stereoscopic microscopy technology, which has a small overlap of stereoscopic images, observes the low resolution image of the edge part of the image and the large projection distortion of the image.

[0049] (7) The variable baseline phase angle stereo photography provided by the present invention has a stable stereo image model and will not cause stereo image flattening. It overcomes the weakness of the original stereo microscope principle that causes serious stereo image flattening when stereo photography is performed at a distance, and improves the stereo photography distance.

[0050] (8) The variable baseline phase angle stereoscopic photography provided by the present invention can effectively maintain a large effective stereoscopic image overlap by changing the stereoscopic photography distance, thereby improving the magnification of digital image stereoscopic microscopy and overcoming the weakness of the original digital image stereoscopic microscopy principle that the stereoscopic image cannot be magnified further when the stereoscopic image overlap is less than 50%. Attached Figure Description

[0051] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort. In the drawings:

[0052] Figure 1 This is a schematic diagram of the structure of a digital image stereomicroscopy system for variable baseline phase angle photography provided by the present invention.

[0053] Figure 2 A flowchart of a digital image stereomicroscopy method for variable baseline phase angle photography provided by the present invention.

[0054] Figure 3 This is a schematic diagram illustrating the principle of spatial projection position and posture correction for digital image stereoscopic photography provided by the present invention. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0056] Example 1

[0057] like Figure 1As shown, this invention provides a digital imaging stereomicroscopy system for variable baseline phase angle photography, including a first digital area array camera a, a second digital area array camera b, a computer data processing device, and a stereo display. The first digital area array camera a and the second digital area array camera b are mounted on the same sliding translation mechanism, which has a central limiting point. The first digital area array camera a and the second digital area array camera b are mirror images of each other on either side of the central limiting point (i.e., one camera is mounted on each side of the central limiting point), and the distance between the first digital area array camera a and the second digital area array camera b and the central limiting point is the same. The first digital area array camera a and the second digital area array camera b are of the same model, and their focal lengths are fixed. The overlap of the images captured by the first digital area array camera a and the second digital area array camera b is maintained at a value greater than a set threshold.

[0058] Optionally, the sliding translation mechanism can be configured as an electric slide rail.

[0059] The equipment system consists of a first digital area array camera (a) and a second digital area array camera (b) installed side-by-side on the left and right sides. They simultaneously capture two-dimensional static images and simultaneously capture video images at a rate greater than 10 frames per second. The lenses of both cameras have fixed focal lengths, and both lenses must have the same focal length and physical distortion coefficient; that is, the two cameras must be identical in type.

[0060] A first digital area array camera a is used to acquire a first photographic digital image of the object being photographed on one side of the central limiting point, and to transmit the first photographic digital image to a computer data processing device.

[0061] The second digital array camera b is used to acquire a second digital image of the photographed object on the other side of the central limiting point and transmit the second digital image to a computer data processing device.

[0062] The computer data processing device is used to perform intrinsic parameter correction and spatial projection position and attitude correction on the first and second photographic digital images to obtain a spatially projected digital image with correct attitude, and then transmit the spatially projected digital image with correct attitude to the stereoscopic display.

[0063] The stereo display is used to display stereo images or video stereo images of the photographed object based on the correct digital images of the spatial projection posture corresponding to the first digital array camera a and the second digital array camera b.

[0064] In one possible implementation, when the first digital area array camera a moves, the second digital area array camera b moves in the opposite direction and by the same amount as the first digital area array camera a.

[0065] In one possible implementation, when the distance for capturing stereoscopic images changes, the distance between the first digital area array camera a and the second digital area array camera b is adjusted synchronously to ensure that the overlap of the images captured by the first digital area array camera a and the second digital area array camera b remains greater than a set threshold of 90%. After adjusting the distance, the two digital area array cameras can be focused using either manual or automatic focusing.

[0066] Before and after adjusting the stereoscopic photography distance, the ratio K between the baseline distance B and the photography distance H between the two digital area array cameras remains unchanged. The baseline distance B represents the length of the line connecting the two digital area array cameras, and the photography distance H represents the distance between the baseline and the object to be photographed.

[0067] In one possible implementation, the positional parameters between the first digital area array camera a and the second digital area array camera b are set as follows:

[0068] K=B1 / H1=B2 / H2=……Bn / Hn

[0069] Δa1b1M1∽Δa2b2M2∽……ΔanbnMn

[0070] ∠a1M1b1=∠a2M2b2=……∠anMnbn

[0071] ∠Ra=∠Rb

[0072] H1≠H2≠……Hn

[0073] B1≠B2≠……Bn

[0074] Wherein, B1 represents the baseline distance between the first digital area array camera a and the second digital area array camera b at the first position, and H1 represents the shooting distance at the first position. B2 represents the baseline distance between the first digital area array camera a and the second digital area array camera b at the second position, and H2 represents the shooting distance at the second position. Bn represents the baseline distance between the first digital area array camera a and the second digital area array camera b at the nth position, and Hn represents the shooting distance at the nth position. Δa1b1M1 represents the triangle formed by the location of the first digital area array camera a1, the location of the second digital area array camera b1, and the location of the photographed object M1, where ∽ indicates that the two triangles are similar. Δa2b2M2 represents the triangle formed by the location of the first digital area array camera a2, the location of the second digital area array camera b2, and the location of the photographed object M2. ΔanbnMn represents the triangle formed by the location of the first digital area array camera an, the location of the second digital area array camera bn, and the location of the photographed object Mn. ∠a1M1b1 represents the angle formed by point a1 of the first digital area array camera, position M1 of the photographed object, and point b1 of the second digital area array camera; ∠a2M2b2 represents the angle formed by point a1 of the first digital area array camera, position M2 of the photographed object, and point b1 of the second digital area array camera; ∠anMnbn represents the angle formed by point a1 of the first digital area array camera, position Mn of the photographed object, and point b1 of the second digital area array camera; ∠Ra represents the angle between the shooting direction of the first digital area array camera a and the baseline B; and ∠Rb represents the angle between the shooting direction of the second digital area array camera b and the baseline B.

[0075] Because when the first digital area array camera a moves, the second digital area array camera b moves in the opposite direction and by the same amount. Therefore, when the first digital area array camera a and the second digital area array camera b move, as long as the phase angles ∠Ra and ∠Rb remain unchanged, the ratio K between the baseline distance B and the shooting distance H between the two digital area array cameras will not change. It is worth noting that when the second digital area array camera b moves, the first digital area array camera a moves in the opposite direction and by the same amount.

[0076] Optionally, when the first digital area array camera a and the second digital area array camera b are mounted on the sliding translation mechanism, they should be mounted on a structure that allows the cameras to rotate in the X, Y, and Z axes. An electric slide rail is mounted on this rotating structure to achieve intelligent electric control of the camera's multi-axis movement, which is more precise and convenient than manual camera control. Figure 1 In the middle, P a1b1This represents the overlapping image captured by the first digital area array camera at point a1 and the second digital area array camera at point b1; P a2b2 This represents the overlapping image captured by the first digital area array camera at point a2 and the second digital area array camera at point b2; P anbn This represents the overlapping image captured by the first digital area array camera at point an and the second digital area array camera at point bn.

[0077] When shooting stereoscopic images, the lenses of the two cameras on the left and right can be focused manually at the same time or intelligently synchronized electric control. The illumination light source can also be set to enable shooting in low-light environments.

[0078] In one possible implementation, the mounting angle ∠Ra of the first digital area array camera a and the mounting angle ∠Rb of the second digital area array camera b are both set to a range of 1°-15° to adjust the height of the stereo model required for stereoscopic image observation.

[0079] In one possible implementation, the threshold c corresponding to the overlap of the images captured by the first digital area array camera a and the second digital area array camera b is set to be greater than 90%.

[0080] This invention provides a digital imaging stereomicroscopy system with variable baseline phase angle photography. It enables two area array cameras to move in opposite directions with equal amounts when the stereo shooting distance changes. During the movement, the ratio K of the stereo shooting distance H to the baseline B remains constant, as does the image overlap and the height ratio of the stereo image model. After image acquisition, the system uses a computer data processing device to perform intrinsic parameter correction and spatial position and attitude correction to eliminate errors in the camera itself and errors caused by system manufacturing and installation. This reduces the precision manufacturing and installation requirements of the system and the camera.

[0081] Example 2

[0082] like Figure 2 As shown, the present invention provides a digital image stereomicroscopy method based on a digital image stereomicroscopy system, comprising:

[0083] S1. Acquire a first digital image using a first digital array camera a, and acquire a second digital image using a second digital array camera b.

[0084] S2. The computer data processing device corrects the intrinsic parameters and spatial projection position and attitude of the first and second photographic digital images to obtain a digital image with correct spatial projection attitude.

[0085] S3. Convert the correctly oriented digital image of the spatial projection into stereoscopic image data using a stereoscopic display and display it on the stereoscopic display.

[0086] In one possible implementation, intrinsic parameter correction includes:

[0087] A first calibration image of the intrinsic parameter calibration board is captured by a first digital area array camera a. A second calibration image of the intrinsic parameter calibration board is captured by a second digital area array camera b. The intrinsic parameter calibration board corresponds to the coordinates of a reference calibration point.

[0088] Obtain the coordinates of the first calibration point in the first calibration image and the coordinates of the second calibration point in the second calibration image, and obtain the first intrinsic parameter correction value between the coordinates of the first calibration point and the coordinates of the reference calibration point, and obtain the second intrinsic parameter correction value between the coordinates of the second calibration point and the coordinates of the reference calibration point.

[0089] The first photographic digital image is rearranged according to the first intrinsic parameter correction value, and the second photographic digital image is rearranged according to the second intrinsic parameter correction value to eliminate image distortion caused by intrinsic parameter error.

[0090] Digital images captured by two cameras (left and right) have different intrinsic parameters, resulting in different lens physical distortions (q), focal lengths (f), and different positions (o) of the light rays projected from the center of the lens onto the CCD sensor. These differences necessitate calculations to unify the intrinsic parameters. The two cameras capture images using a dedicated image intrinsic parameter calibration board. Image matching calculations obtain the coordinates of calibration points. The difference between these calibration point coordinates and the coordinates obtained from the image matching calculations is compared to calculate the intrinsic parameter correction value. This correction value is then used to rearrange the images, eliminating image distortion caused by intrinsic parameter errors.

[0091] In one possible implementation, spatial projection position and attitude correction includes:

[0092] An image matching algorithm is used to obtain the spatial projection position and attitude adjustment parameters of the second digital image captured by the second digital array camera b relative to the first digital image captured by the first digital array camera a.

[0093] Based on the spatial projection position and attitude adjustment parameters, the images of the first digital array camera a and the second digital array camera b are digitally rearranged to obtain the corresponding rearranged images.

[0094] In this embodiment, the spatial projection position attitude adjustment parameter is the spatial projection attitude difference between the second digital image captured by the second digital array camera b and the first digital image captured by the first digital array camera a. It can also be considered as the spatial projection attitude difference between the first digital image captured by the first digital array camera a and the second digital image captured by the second digital array camera b. Therefore, the second digital image or the first digital image can be adjusted according to the spatial projection position attitude adjustment parameter. Alternatively, the first digital image and the second digital image can each be adjusted by half according to the spatial projection position attitude adjustment parameter.

[0095] Rearrange the images as correctly posed digital images in stereoscopic photographic space projection.

[0096] After the computer equipment reads the left and right digital images (after eliminating camera internal parameter errors), because the captured images were projected at an angle with an installation angle, and because the two cameras have relative errors in terms of front-to-back, left-to-right, up-down, and rotation, the projected images are distorted digital images. The left and right digital images are projected in different directions, resulting in different distortions. Therefore, they cannot be directly used to construct a stereoscopic image for observation. The distortion must be corrected, and the projected images must be rearranged to restore the correct digital images to the original shooting posture. The principle of restoration is as follows... Figure 3 As shown.

[0097] In one possible implementation, an image matching algorithm is used to obtain spatial projection position and attitude adjustment parameters of the second digital image captured by the second digital area array camera b relative to the first digital image captured by the first digital area array camera a, including:

[0098] Search for multiple corresponding projection points on the first and second digital images, and based on these multiple corresponding projection points, obtain the spatial projection rotation angle and scaling correction value of the second digital image relative to the first digital image during photography, thus obtaining the spatial projection position attitude adjustment parameters.

[0099] The process of restoring the correct digital image to the shooting posture is the computer-aided image matching calculation. The purpose of the image matching is to accurately find multiple corresponding projection points on the left and right images, calculate the spatial projection rotation angle and scaling correction value of the right image relative to the left image at the time of shooting, and calculate the relative spatial projection position and posture data of the two cameras.

[0100] Eliminating intrinsic parameter errors in left and right digital images involves unifying the focal length f and image coordinate system of the left and right images to construct stereo vision.

[0101] like Figure 3As shown, this is a schematic diagram of a digital image principle that rearranges spatial projection images to restore them to their correct spatial projection posture at the time of capture. Figure 3 In the diagram, P1 is the image from the left camera, P2 is the image from the right camera, s1 is the focal point of the left camera, s2 is the focal point of the right camera, f1 is the focal length of the left camera, f2 is the focal length of the right camera, o1 is the center point of the left camera image, o2 is the center point of the right camera image, o1-xy is the coordinate system of the left image, o2-xy is the coordinate system of the right image, the O-XYZ coordinate system is the spatial projection correction coordinate system established in parallel with the focal length f1 of the left camera image and the camera image coordinate system, o1-xy, κ, ω, Ф are the spatial projection rotation angles of the right camera image in the O-XYZ coordinate system, X2, Y2, Z2 are the spatial translations of the right camera image in the O-XYZ coordinate system, A and B are the spatial object points of the photograph, a1 and b1 are the projection points of the spatial object points on the left image P1, a2 and b2 are the projection points of the spatial object points on the right image P2, and M is the stereoscopic photography baseline, which is the distance between the focal points of the left and right cameras.

[0102] Calculate the orientation and coordinates of the corresponding object in the XYZ spatial coordinate system when the left and right cameras are taking pictures, match the results of the intersection with the spatial projection, the projection centers s1 and s2 of the left and right cameras, the spatial object points A and B of the stereoscopic photograph, the rotation orientation elements κ and Ф of the image in the XYZ spatial coordinate system, and the rotation angle ω, calculate the rotation matrix R′, the relationship between the spatial coordinates x′, y′, z′, the image point coordinates x and y, and the camera lens focal length f is as follows:

[0103]

[0104] If the orientation of the image within the XYZ spatial coordinate system is known

[0105]

[0106] The position and orientation of an object in the XYZ spatial coordinate system in stereoscopic vision

[0107]

[0108] in

[0109] R0 = R·(R′) -1

[0110]

[0111] Obtain the relative spatial projection position and attitude data of the two cameras in the left and right images.

[0112] The left and right images are restored to their correct spatial projection posture at the time of photography, and then pushed by the computer to a stereoscopic display to form a stereoscopic image for observation. Stereoscopic display observation employs frame-sequence active shutter stereoscopic observation mode, polarized light stereoscopic observation mode, and naked-eye stereoscopic observation mode.

[0113] The digital image stereomicroscopy system and method for variable baseline phase angle photography provided in this application eliminates manufacturing and installation errors of variable baseline phase angle photography and manufacturing and pairing internal parameter errors of the two cameras by correcting the camera intrinsic parameters and the spatial projection position and attitude of the image on the first image of the left camera and the second image of the right camera, thereby reducing the system manufacturing and installation requirements.

[0114] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A digital image stereomicroscopy system for variable baseline phase angle photography, characterized in that, It includes a first digital array camera a, a second digital array camera b, a computer data processing device, and a stereoscopic display; The first digital area array camera a and the second digital area array camera b are mounted on the same sliding translation mechanism. The sliding translation mechanism is provided with a central limiting point. The first digital area array camera a and the second digital area array camera b are mirror images of each other on both sides of the central limiting point, and the distance between the first digital area array camera a and the second digital area array camera b and the central limiting point is the same. The first digital area array camera a and the second digital area array camera b use the same model and have the same lens focal length f. The focal lengths of the first digital area array camera a and the second digital area array camera b are fixed, and the overlap of the images captured by the first digital area array camera a and the second digital area array camera b is kept greater than a set threshold c. The first digital array camera a and the second digital array camera b simultaneously capture digital images, respectively obtaining a first digital image and a second digital image, and then transmitting both the first and second captured digital images to a computer data processing device. The computer data processing device is used to perform intrinsic parameter correction and spatial projection position and attitude correction on the first and second photographic digital images, rearrange the digital images to obtain a digital image with correct spatial projection attitude, and transmit the digital image with correct spatial projection attitude to the stereoscopic display. The stereo display is used to display stereo images or video stereo images of the photographed object based on the correct digital images of the spatial projection postures of the first digital array camera a and the second digital array camera b. When the distance between the first digital array camera a and the second digital array camera b changes, the overlap of the images captured by the first digital array camera a and the second digital array camera b remains greater than a set threshold c. Before and after the adjustment, the ratio K between the baseline distance B and the shooting distance H between the two digital area array cameras remains unchanged. The baseline distance B represents the length of the line connecting the two digital area array cameras, and the shooting distance H represents the distance between the baseline and the object to be photographed. The positional parameters between the first digital area array camera a and the second digital area array camera b are set as follows: K = B1 / H1 = B2 / H2 = ... = Bn / Hn Δa1b1M1∽Δa2b2M2∽……ΔanbnMn ∠a1M1b1=∠a2M2b2=……∠anMnbn ∠Ra=∠Rb H1≠H2≠……Hn B1≠B2≠……Bn Wherein, B1 represents the baseline distance of the first digital area array camera a and the second digital area array camera b in the first position, H1 represents the photographing distance in the first position; B2 represents the baseline distance of the first digital area array camera a and the second digital area array camera b in the second position, H2 represents the photographing distance in the second position; Bn represents the baseline distance of the first digital area array camera a and the second digital area array camera b in the nth position, Hn represents the photographing distance in the nth position; Δa1b1M1 represents the triangle formed by the first digital area array camera a, the second digital area array camera b1 and the position M1 of the photographed object, ∽ represents that two triangles are similar triangles, Δa2b2M2 represents the triangle formed by the first digital area array camera a2, the second digital area array camera b2 and the position M2 of the photographed object, ΔanbnMn represents the triangle formed by the first digital area array camera an, the second digital area array camera bn and the position Mn of the photographed object; ∠a1M1b1 represents the included angle formed by the first digital area array camera a1, the position M1 of the photographed object and the second digital area array camera b1, ∠a2M2b2 represents the included angle formed by the first digital area array camera a1, the position M2 of the photographed object and the second digital area array camera b1, ∠anMnbn represents the included angle formed by the first digital area array camera a1, the position Mn of the photographed object and the second digital area array camera b1, ∠Ra represents the included angle between the shooting direction of the first digital area array camera a and the baseline B, and ∠Rb represents the included angle between the shooting direction of the second digital area array camera b and the baseline B.

2. The digital image stereomicroscopy system of claim 1, wherein, When the first digital area array camera a moves, the second digital area array camera b moves oppositely and equally with the first digital area array camera a.

3. The digital image stereomicroscopy system of claim 1, wherein, The installation included angle ∠Ra of the first digital area array camera a and the installation included angle ∠Rb of the second digital area array camera b are both set to 1°-15°.

4. The variable-baseline cross-angle photogrammetry digital image stereomicroscopy system of claim 1, wherein, The threshold c corresponding to the overlap of the images captured by the first digital area array camera a and the second digital area array camera b is set to maintain a value greater than 1. 90%.

5. A digital image stereomicroscopy method based on the digital image stereomicroscopy system according to any one of claims 1-4, characterized in that, It comprises: The first digital area array camera a collects the first photographing digital image, and the second digital area array camera b collects the second photographing digital image; The computer data processing device corrects the internal parameters and the spatial projection position and posture of the first photographing digital image and the second photographing digital image to obtain the spatial projection posture correct digital image; The spatial projection posture correct digital image is converted into a stereoscopic image data by a stereoscopic display, and displayed on the stereoscopic display.

6. The digital image stereo microscopy method of claim 5, wherein, The internal parameter correction comprises: The first digital area array camera a photographs the first calibration image of the internal parameter calibration board, and the second digital area array camera b photographs the second calibration image of the internal parameter calibration board, and the internal parameter calibration board corresponds to the reference calibration point coordinates; The first calibration point coordinate in the first calibration image and the second calibration point coordinate in the second calibration image are acquired, and the first internal parameter correction value between the first calibration point coordinate and the reference calibration point coordinate and the second internal parameter correction value between the second calibration point coordinate and the reference calibration point coordinate are acquired; The first photographic digital image is rearranged according to the first internal parameter correction value, and the second photographic digital image is rearranged according to the second internal parameter correction value, so as to eliminate the image deformation caused by the internal parameter error.

7. The digital image stereo microscopy method of claim 5, wherein, The spatial projection position and posture correction is performed, including: An image matching algorithm is used to acquire the spatial projection position and posture adjustment parameter of the second photographic digital image taken by the second digital area array photographic camera b relative to the first photographic digital image taken by the first digital area array photographic camera a; According to the spatial projection position and posture adjustment parameter, the digital image rearrangement is performed on the first digital area array photographic camera a image and the second digital area array photographic camera b image, so as to obtain the corresponding rearranged image; The rearranged image is taken as the stereophotography spatial projection posture correct digital image.

8. The digital image stereo microscopy method of claim 7, wherein, An image matching algorithm is used to acquire the spatial projection position and posture adjustment parameter of the second photographic digital image taken by the second digital area array photographic camera b relative to the first photographic digital image taken by the first digital area array photographic camera a, including: A plurality of homonymous projection points on the first photographic digital image and the second photographic digital image are searched, and according to the plurality of homonymous projection points, the spatial projection rotation angle and the scaling ratio correction value of the second photographic digital image relative to the first photographic digital image during photographing are acquired, so as to obtain the spatial projection position and posture adjustment parameter.

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