CN110736447B - Vertical-direction horizontal position calibration method for integrated image acquisition equipment - Google Patents
Vertical-direction horizontal position calibration method for integrated image acquisition equipment Download PDFInfo
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- G01C11/00—Photogrammetry or videogrammetry, e.g. stereogrammetry; Photographic surveying
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Abstract
The invention provides a method for checking the horizontal position of integrated image acquisition equipment in the vertical direction, which comprises the steps of arranging an indoor checking field, calibrating a camera lens internal parameter, and measuring the approximate horizontal position of the image acquisition equipment in the vertical direction, wherein the method comprises the steps of utilizing the image acquisition equipment to shoot two coordinate grid plates in sequence, calculating the included angle between the approximate direction of a main optical axis and the horizontal direction, and determining the approximate horizontal position of the image acquisition equipment in the vertical direction; accurately measuring horizontal position parameters of the image acquisition equipment, including initial direction control point image acquisition and parameter calculation, and multi-direction control point image acquisition and parameter calculation; and under the condition that the difference of the calculated included angle values in all directions is smaller than a set threshold value, calculating an average value to set a horizontal direction zero position of the vertical collimation part direction of the holder. The technical scheme of the invention is suitable for the calibration of the horizontal position of various integrated image acquisition devices in the vertical direction, and is particularly suitable for the calibration of an integrated image acquisition system in a high-precision photogrammetry task.
Description
Technical Field
The invention belongs to the field of digital photogrammetry, and particularly relates to a method for calibrating the horizontal position of an integrated image acquisition device in the vertical direction.
Background
The integrated image acquisition equipment is usually used for acquiring the appearance images of buildings, the surface area of a target object is large in general, and a plurality of shooting stations are required to be erected for shooting the images to cover the whole surface. Since the integrated image capturing device does not have a measurement function, in order to unify the coordinate systems of the plurality of shooting sites, planning of the shooting sites and the shooting postures needs to be performed by using a total station.
After the total station is used for laying all the control points, integrated image acquisition equipment is assumed at all the control points. In order to enable the resolution of the shot image to meet the engineering detection requirement, the acquired image needs to meet a certain overlapping degree requirement and a resolution requirement, so that the image acquisition equipment needs to be controlled according to the calculated angle in the planning and designing process.
Since the reference plane measured by the total station in a small area is a horizontal plane, the integrated image capturing device also needs to be photographed in a horizontal state. The horizontal state of collection equipment can be accomplished through installing high accuracy flattening base additional, like this alright with the horizontal angle measurement that utilizes numerical control cloud platform horizontal direction's rotation to realize image acquisition equipment, but vertical angle measurement still need obtain the accurate horizontal position of photographic equipment main optical axis in the vertical direction at first, just can realize vertical angle's measurement, need accomplish integrated form image acquisition equipment's vertical direction horizontal position calibration promptly.
Compared with professional photogrammetric equipment, the difficulty and the existing problems of the calibration method of the integrated image acquisition equipment mainly lie in that:
(1) an indoor calibration field specially designed for integrated image acquisition equipment does not exist, and various parameters of the image acquisition equipment cannot be accurately calibrated;
(2) the integrated image acquisition equipment does not have the measurement function of a professional measuring instrument, but needs to realize angle measurement in the use process. The angle control of horizontal direction can be accomplished on automatic photography orientation mode basis, but vertical direction is because equipment adopts the integrated mode to build, through the fixed back of connecting piece between photography equipment and the numerical control cloud platform, and the acquiescent initial position of cloud platform is not photography equipment horizontal position in vertical direction, consequently need carry out the accuracy to photography equipment vertical direction horizontal position parameter and examine the school, makes equipment possess vertical angle measurement function.
(3) The calibration method used at present mainly comprises the steps of shooting two leveling rulers by using image acquisition equipment, reading the reading of the leveling ruler corresponding to the center of an image, and calculating the horizontal position parameter in the vertical direction by using the height difference of the reading scribed lines of the two leveling rulers and the horizontal distance between the two leveling rulers. However, the method is limited in that the reading process of the leveling rod corresponding to the center of the image is estimated and read, and the estimated and read precision is low; in addition, the photographing apparatus and the two leveling rods cannot be guaranteed to be located on the same straight line. Therefore, the accuracy of the finally calculated horizontal position parameter in the vertical direction cannot be guaranteed.
Disclosure of Invention
The invention provides a calibration method for the horizontal position of an integrated image acquisition device in the vertical direction, which aims to solve the difficulties and problems in the background technology.
The technical scheme of the invention provides a method for detecting and correcting the horizontal position of integrated image acquisition equipment in the vertical direction, the integrated image acquisition equipment consists of high-resolution photographic equipment, a high-precision numerical control tripod head, a high-precision leveling base, a connecting piece between the photographic equipment and the tripod head and a tripod, and the method comprises the following steps,
step 1, indoor calibration field layout, which comprises the steps of designating the area of an indoor calibration field, two-dimensional calibration plate layout, coordinate grid plate layout and three-dimensional control point layout;
step 2, calibrating lens internal parameters, namely replacing a telephoto lens with a wide-angle lens, locking a focusing ring, completing the calibration of the lens internal parameters by using a two-dimensional calibration plate, and performing distortion correction on subsequent shot images and providing internal orientation elements of the camera;
step 3, determining the approximate horizontal position of the image acquisition equipment in the vertical direction, wherein the method comprises the steps of utilizing the image acquisition equipment to shoot two coordinate grid plates in sequence, marking the position of the central point of an image on an actual coordinate grid plate, utilizing a total station to determine the coordinates of a marking point, calculating the included angle between the approximate direction of a main optical axis and the horizontal direction, and determining the approximate horizontal position of the image acquisition equipment in the vertical direction according to the obtained result;
step 4, accurately measuring horizontal position parameters of the image acquisition equipment, including initial direction control point image acquisition and parameter calculation, and multi-direction control point image acquisition and parameter calculation; and under the condition that the calculated included angle value in each direction is less than a set threshold value, calculating an average value to serve as a final included angle value between the main optical axis direction of the camera and the horizontal direction, and setting a horizontal direction zero position of the vertical collimation part direction of the holder according to the included angle value, wherein the vertical collimation part direction of the holder is the main optical axis direction of the photographic equipment.
And the implementation manner of the step 2 is that other fixed-focus wide-angle lenses are used for replacing a long-focus fixed-focus lens in the image acquisition equipment to finish the internal reference calibration of the photographic equipment, in the subsequent image acquisition process, the fixed-focus wide-angle lenses in the step 2 are adopted by the lenses, the focusing ring is locked, and the focusing operation cannot be carried out.
The step 3 is realized by setting the horizontal rotating part of the tripod head to be in a horizontal state and setting the angle of the vertical rotating part of the tripod head to be an initialized default angle by using the high-precision leveling base; shooting the two coordinate grid plates by using image acquisition equipment in sequence, and marking the positions corresponding to the centers of the images on the two coordinate grid plates respectively; respectively measuring three-dimensional coordinates of the two mark points by using a total station, and calculating an included angle between the approximate direction of the main optical axis and the horizontal direction; and adjusting the vertical rotating part of the tripod head to be approximately in a horizontal state according to the calculated included angle value.
Furthermore, the implementation of step 4 is as follows,
firstly, carrying out initial direction control point image acquisition and parameter calculation, wherein the initial direction control point image acquisition and parameter calculation comprises the steps of utilizing a high-precision leveling base to set a horizontal rotating part of a horizontal holder, utilizing a total station and a steel ruler to measure an approximate value of a coordinate of a photographing center of image acquisition equipment, and designating a certain direction as the initial direction of the horizontal rotating part of the holder; shooting the three-dimensional control points of the wall surface of the indoor calibration field in the starting direction by using image acquisition equipment; calculating an included angle between the direction of a main optical axis and the horizontal direction in the vertical direction of the image acquisition equipment by using the shot three-dimensional control points;
secondly, multi-direction control point image acquisition and parameter calculation, including controlling a horizontal rotating part of a tripod head to aim at different directions according to a specified horizontal angle, shooting three-dimensional control points in the calibration center in all directions, and calculating the included angle between a main optical axis and the horizontal direction of the image acquisition equipment in the vertical direction in all horizontal directions by using the three-dimensional control points;
and finally, when the calculated included angle value in each direction is less than a set threshold value, calculating an average value to be used as a final included angle value between the main optical axis direction of the camera and the horizontal direction, and further accurately checking and correcting the horizontal position of the image acquisition equipment in the vertical direction.
The invention provides a calibration method for the horizontal position of integrated image acquisition equipment in the vertical direction, which has the beneficial effects that: the problem that vertical angle measurement cannot be realized due to the fact that the horizontal direction cannot be determined by integrated image acquisition equipment is solved; the problem that the existing calibration method can only approximately acquire the horizontal position of the integrated image acquisition equipment in the vertical direction is solved, and accurate calibration parameters are provided for the equipment. The technical scheme of the invention is suitable for the calibration of the horizontal position of various image acquisition equipment in the vertical direction, which is integrated by photographic equipment, a numerical control holder and corresponding connecting components, and is particularly suitable for the calibration of an integrated image acquisition system in a high-precision photogrammetry task.
Drawings
Fig. 1 is a schematic composition diagram of an integrated image capturing device according to an embodiment of the present invention.
Fig. 2 is a schematic diagram of vertical angle definition of the image capturing device according to the embodiment of the present invention.
Fig. 3 is a schematic diagram of an indoor calibration field according to an embodiment of the present invention.
Fig. 4 is a schematic diagram of a two-dimensional calibration plate according to an embodiment of the invention.
Fig. 5 is a schematic diagram of a coordinate grid plate according to an embodiment of the present invention.
Fig. 6 is a schematic view of the arrangement of three-dimensional control points on the wall surface according to the embodiment of the present invention.
FIG. 7 is a schematic diagram illustrating an exemplary embodiment of an apparatus for measuring a vertical approximate horizontal position of an image capturing device.
Fig. 8 is a schematic diagram of an external orientation angle element of an image capturing apparatus according to an embodiment of the present invention.
Detailed Description
The invention is further illustrated by the following examples in conjunction with the accompanying drawings.
As shown in fig. 1, an integrated image capturing device in the prior art generally comprises a high resolution photographing device (such as a single lens reflex camera, an industrial camera, etc.), a high precision digital control platform, a high precision leveling base, a connecting member between the photographing device and the platform, and a tripod, wherein the photographing device is mounted on the digital control platform through the connecting member, the leveling base is mounted below the digital control platform, and the base is connected to the tripod. The invention provides a method for calibrating a horizontal position in a vertical direction for integrated image acquisition equipment, which is used for acquiring a horizontal position parameter in the vertical direction of the image acquisition equipment and further accurately leveling the image acquisition equipment in the vertical direction. As shown in fig. 2, the vertical angle of the image capturing device is defined as: the included angle between the main optical axis direction of the photographic equipment and the horizontal direction is in the range of [ -90 degrees, 90 degrees ]; or the included angle between the direction of the vertical rotating part of the tripod head and the horizontal direction is in the range of [ -90 degrees, 90 degrees ].
The method for calibrating the horizontal position of the integrated image acquisition equipment in the vertical direction comprises the following steps: the method comprises the steps of indoor calibration field layout, lens internal reference calibration, image acquisition equipment vertical approximate horizontal position determination, image acquisition equipment vertical horizontal position accurate determination and the like.
Step 1, laying an indoor checking field: the method comprises the steps of appointing the area of an indoor calibration field, laying a two-dimensional calibration plate, laying a coordinate grid plate and laying three-dimensional control points.
The area of the indoor calibration field can be preset, and in the specific implementation, the area mainly considers that the wall surface range capable of being clearly photographed in the calibration field is large enough after a camera focuses to infinity in the photographing process, and the calibration marks are uniformly distributed on the wall surface. When the camera is placed in the middle of the calibration field, the distance between the camera and each wall surface is about 7.5m, and the field range of the camera is about 9m multiplied by 6m, so that enough calibration marks, namely three-dimensional control points, in the field range can be ensured to be used for calculating the exterior orientation element of the camera in the step 4.
The calibration content mainly relates to resolving camera internal parameters, approximate horizontal position measurement and accurate horizontal position measurement. As shown in fig. 3, the area of the indoor calibration field is selected to be about 15m × 15m, the ground is a horizontal ground, and the surrounding wall surfaces are vertical smooth wall surfaces. And (3) layout is required in a calibration field: as shown in fig. 4, 1 two-dimensional calibration plate is used for calculating lens internal parameters; as shown in fig. 5, 2 grid plates with grid size of 5mm × 5mm are used to determine the approximate horizontal position; as shown in fig. 6, three-dimensional control points are uniformly distributed on the wall surface around the calibration field for computing external parameters of the camera and accurately measuring the horizontal position. The coordinate system in the calibration center is measured and established by a high-precision total station, and the coordinates of the measured point include: image acquisition equipment rack site coordinates (X)C,YC,ZC) 2 coordinates of the mark on the coordinate grid plate (X)M1,YM1,ZM1) And (X)N1,YN1,ZN1) Wall surface control point coordinate (X)i,Yi,Zi). The height of the image acquisition equipment is measured by a steel ruler distance measuring method.
Step 2, calibrating the internal parameters of the lens: and the other fixed-focus wide-angle lenses are used for replacing the long-focus fixed-focus lenses in the image acquisition equipment to finish the calibration of the internal parameters of the photographic equipment, and the acquired internal parameters are used for carrying out distortion correction on the subsequently acquired images and providing the internal orientation elements of the camera for the subsequent calculation process. In the subsequent steps, the fixed-focus wide-angle lens used in the step is utilized, and the lens can not be focused any more in the calibration process.
In general, when an image acquisition device is used to acquire an appearance image of a target, the shooting distance (>30m) is relatively long, so that in order to meet the requirement for acquiring a high-resolution target surface image, a telephoto fixed-focus lens (the focal length is greater than or equal to 600mm) is generally required to be used by a photographic device, but the field range of the telephoto fixed-focus lens is very small, which is not beneficial to calculating the horizontal position parameter of the image acquisition device in the vertical direction. The vertical angle of the image acquisition equipment is mainly measured by calculating the included angle between the main optical axis direction and the horizontal direction of the photographic equipment, so that the horizontal position of the equipment is not influenced by using lenses with different focal lengths. Embodiments replace the tele lens with a wide lens, locking the focus ring. For example, a 28mm focal length fixed-focus wide-angle lens can be used to replace a telephoto lens of an image acquisition device to complete a whole set of calibration process.
And placing the two-dimensional calibration plate near a certain wall surface of the checking field, and erecting image acquisition equipment in the checking field. And focusing a lens of the photographic equipment to infinity, locking a focusing ring, shooting the two-dimensional calibration plate at different angles by using image acquisition equipment, and completing internal reference calibration of the camera according to a conventional internal reference calibration flow. The acquired internal parameters are used for carrying out distortion correction on the subsequently acquired images and providing internal orientation elements of the camera for the subsequent calculation process. In the subsequent image acquisition process, the lenses all adopt the fixed-focus wide-angle lens used in the step, and the focusing ring is locked, so that the focusing operation cannot be carried out.
And 3, measuring the approximate horizontal position of the image acquisition equipment in the vertical direction. The method comprises the steps of sequentially shooting two coordinate grid plates by using image acquisition equipment, marking the position of an image center point on an actual coordinate grid plate, measuring the coordinates of a mark point by using a total station, and calculating the included angle between the approximate direction of a main optical axis and the horizontal direction; and determining the approximate horizontal position of the image acquisition equipment in the vertical direction according to the calculation result.
The implementation mode of the step 3 is as follows:
initializing image acquisition equipment, utilizing high accuracy flattening base to set the horizontal rotating part of cloud platform into horizontality, setting the vertical rotating part angle of cloud platform for acquiescence initial angle, this angle is the initial contained angle of camera main optical axis direction and horizontal direction promptly. Normally, the default initial angle has a certain angle value with the horizontal direction, and is not the horizontal state. The main purpose of this step is to detect the approximate value of the included angle between the direction (i.e. the main optical axis direction of the camera) of the default initial position of the vertical rotating part of the pan/tilt and the horizontal direction, and then set the vertical rotating part of the pan/tilt to be in an approximately horizontal state.
Sequentially shooting two coordinate grid plates by using image acquisition equipment, and marking the positions corresponding to the centers of the images on the coordinate grid plates after shooting is finished each time; measuring three-dimensional coordinates of two marked points respectively by using a total station, wherein a point position space connecting line marked on the two grid plates can be regarded as an approximate straight line of a main optical axis of the camera, and calculating an included angle between the approximate direction of the main optical axis and the horizontal direction, so that the approximate horizontal position of the image acquisition equipment in the vertical direction can be determined, and the position provides an approximate value for the next accurate calculation; and adjusting the vertical rotating part of the tripod head to be approximately in a horizontal state according to the calculated included angle value.
In an embodiment, the image capture device is mounted in a calibration field with two coordinate grid plates (M, N) in relative positions as shown in FIG. 7. Firstly shooting a coordinate grid plate M by using a camera, marking the position of the center of an image on the coordinate grid plate image in the obtained image, marking the mark image on an actual coordinate grid plate by using a plus sign, and marking the point name as M1Measuring M with high-precision total station1Coordinate (X)M1,YM1,ZM1) (ii) a Then, the coordinate grid plate N is subjected to the same operation process to obtain the plus sign N on the grid plate N1Coordinate (X) ofN1,YN1,ZN1)。M1And N1Can be considered to be a line approximately representing the main optical axis of the photographic apparatus in space, using M1And N1The approximate included angle between the main optical axis direction and the horizontal direction can be calculated by the three-dimensional coordinates:
wherein D isM1N1Is M1And N1Distance between two points:
in the process, because a certain error is generated when the coordinate grid plate is marked, the calculated position is obtained
The value is the angle between the approximate direction of the main optical axis of the camera and the horizontal direction. Is obtained to
And then, adjusting the vertical rotating part of the holder to be approximately horizontal.
And 4, step 4: and accurately measuring the horizontal position parameter of the image acquisition equipment. The method comprises the steps of initial direction control point image acquisition and parameter calculation, and multi-direction control point image acquisition and parameter calculation; under the condition that the calculated included angle value in each direction is less than a set threshold value, calculating an average value to be used as a final included angle value between the main optical axis direction of the camera and the horizontal direction; the horizontal direction zero position of the vertical aiming part direction (namely the main optical axis direction of the photographic equipment) of the holder can be set according to the included angle value.
The implementation manner of the step 4 is as follows:
firstly, the image acquisition of the initial direction control point and the parameter calculation are carried out. The method comprises the steps that a high-precision leveling base is used for placing a horizontal rotating part of a leveling pan head, a total station and a steel ruler are used for measuring an approximate value of a coordinate of a photographing center of image acquisition equipment, and a certain direction is designated as an initial direction of the horizontal rotating part of the pan head; shooting three-dimensional control points of the wall surface of the indoor calibration field in the starting direction by using image acquisition equipment, wherein the image at least needs to comprise 3 three-dimensional control points; and calculating an included angle between the direction of a main optical axis and the horizontal direction in the vertical direction of the image acquisition equipment by utilizing the shot three-dimensional control points.
And secondly, multi-direction control point image acquisition and parameter calculation. The horizontal rotating part of the cradle head is controlled to aim at different directions according to the specified horizontal angle, three-dimensional control points in the calibration center are shot in all directions, and the included angle between the main optical axis and the horizontal direction in the vertical direction of the image acquisition equipment in each horizontal direction is calculated by utilizing the three-dimensional control points.
And finally, when the calculated included angle value in each direction is less than a set threshold value, calculating an average value to be used as a final included angle value between the main optical axis direction of the camera and the horizontal direction, and further accurately checking and correcting the horizontal position of the image acquisition equipment in the vertical direction.
In the embodiment, the image acquisition equipment is assumed to be in the three-dimensional coordinates (X) of the central area of the check field and the station building site CC,YC,ZC) Measuring with high-precision total station, measuring height difference h from center of camera to ground point with steel ruler to obtain central coordinate (X)S,YS,ZS) Wherein X isS＝XC,YS＝YC,ZS＝ZC+h。
And 4.1, starting direction control point image acquisition and parameter calculation. The image acquisition equipment is aligned to a three-dimensional control point in a certain area of the calibration field, the current alignment direction is set to be the zero direction of the horizontal rotating part of the holder, the image acquisition equipment is used for shooting the three-dimensional control point on the wall surface of the calibration field, and the image can be ensured to cover more than 3 three-dimensional control points at least. And solving the spatial position and the attitude of the camera by utilizing a collinear condition equation. The collinearity condition equation is:
wherein f is the camera main distance and is obtained in the step 1; (X)S,YS,ZS) Is a photographing center coordinate; (X, Y, Z) is three-dimensional control point coordinates, and (X, Y) is three-dimensionalThe image point coordinates of the control points; a isi,bi,ciFor the rotation matrix element, i ═ 1,2, 3:
the rotation matrix element includes an external orientation angle element of the photographing apparatus
ω, κ. In which, as shown in figure 8,
omega and kappa are a pitch angle, a roll angle and a picture rotation angle respectively. Wherein the content of the first and second substances,
namely, the calibration parameters of the horizontal position of the image acquisition equipment in the vertical direction to be determined. The relationship between the exterior orientation angle element and the rotation matrix element is as follows:
b1＝cosωsinκ
b2＝cosωcosκ
b3＝-sinω
since the collinear condition equation is a nonlinear equation, when more than 3 three-dimensional control points are known, the equation needs to be linearized, unknowns are solved according to the least square principle, and the solving process is iterative calculation, so that the space position of the photographing center and the initial value of the camera attitude need to be provided, namely, the (X) needs to be determinedS,YS,ZS) And
initial values of ω, κ. The initial value of the position of the photographic center is obtained by the measuring mode of the total station and the steel ruler; 3 angles of camera pose: when the horizontal rotating part of the holder is in a horizontal state, the initial value of kappa is 0; the aiming direction of the horizontal rotating part of the holder is set to be zero, and then the initial value of omega is 0; the vertical rotating part of the tripod head is approximately set to be in a horizontal state in the step 3
Is 0. After the collinear condition equation is solved by adopting a least square method, the attitude angle of the vertical rotating part of the holder (namely the attitude angle of the vertical rotating part of the holder) can be obtained
) The exact numerical value of (c).
And 4.2, acquiring images of the multi-direction control points and calculating parameters. After the step 4.1 is completed, the numerical control holder is set with a plurality of rotation angle values in the horizontal direction, such as 45 °,90 °, 135 °, 180 °, 225 °, 270 °, 315 °. The initial values of ω for the different horizontal rotation angles are 45 °,90 °, 135 °, 180 °, 225 °, 270 °, 315 °, respectively, corresponding to the initial orientation in step 4.1. And if the horizontal rotating part of the holder is in a horizontal state at each horizontal angle, the initial value of k is 0. The vertical rotating parts of the holder are all approximately set to be in a horizontal state according to the step 3Then, then
Is 0. Calculating the attitude angle of the vertical rotating part of the holder corresponding to the horizontal rotating angle according to the method for calculating the attitude of the photographic equipment by utilizing the collinear condition equation in the step 4.1
Comparing the attitude angle of the vertical rotating part of the tripod head calculated in each horizontal direction
When all calculated values are present
When the difference between the two is less than the set threshold value, calculating
Average value of (2)
Will be provided with
And as a calibration value of the horizontal position of the image acquisition equipment in the vertical direction, the horizontal zero position of the vertical collimation part of the holder can be set according to the value. In specific implementation, the threshold value can be preset, and the suggested value is less than 2 ″.
In specific implementation, the automatic operation of the process can be realized by adopting a computer software technology, and an accurate calibration result is obtained.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (4)
1. The utility model provides an integrated form image acquisition equipment vertical direction horizontal position calibration method, integrated form image acquisition equipment comprises high resolution photography equipment, high accuracy numerical control cloud platform, high accuracy flattening base, photographic equipment and connecting piece and tripod between the cloud platform, its characterized in that: comprises the following steps of (a) carrying out,
step 1, indoor calibration field layout, which comprises the steps of designating the area of an indoor calibration field, two-dimensional calibration plate layout, coordinate grid plate layout and three-dimensional control point layout;
step 2, calibrating lens internal parameters, namely replacing a telephoto lens with a wide-angle lens, locking a focusing ring, completing the calibration of the lens internal parameters by using a two-dimensional calibration plate, and performing distortion correction on subsequent shot images and providing internal orientation elements of the camera;
step 3, determining the approximate horizontal position of the image acquisition equipment in the vertical direction, wherein the method comprises the steps of utilizing the image acquisition equipment to shoot two coordinate grid plates in sequence, marking the position of the central point of an image on an actual coordinate grid plate, utilizing a total station to determine the coordinates of a marking point, calculating the included angle between the approximate direction of a main optical axis and the horizontal direction, and determining the approximate horizontal position of the image acquisition equipment in the vertical direction according to the obtained result;
step 4, accurately measuring horizontal position parameters of the image acquisition equipment, including initial direction control point image acquisition and parameter calculation, wherein the realization mode is that after the vertical rotating part of the holder is approximately set to be in a horizontal state from the step 3, the space position and the attitude of the camera are solved by utilizing a collinear condition equation, and the multi-direction control point image acquisition and the parameter calculation are carried out; and under the condition that the calculated included angle value in each direction is less than a set threshold value, calculating an average value to serve as a final included angle value between the main optical axis direction of the camera and the horizontal direction, and setting a horizontal direction zero position of the vertical collimation part direction of the holder according to the included angle value, wherein the vertical collimation part direction of the holder is the main optical axis direction of the photographic equipment.
2. The integrated image acquisition device vertical horizontal position calibration method according to claim 1, wherein: and 2, replacing a long-focus fixed-focus lens in the image acquisition equipment with other fixed-focus wide-angle lenses to finish the internal reference calibration of the photographic equipment, wherein in the subsequent image acquisition process, the fixed-focus wide-angle lenses in the step 2 are adopted by the lenses, and the focusing ring is locked, so that the focusing operation cannot be carried out.
3. The integrated image acquisition device vertical horizontal position calibration method according to claim 1, wherein: the implementation mode of the step 3 is that the horizontal rotating part of the tripod head is set to be in a horizontal state by utilizing the high-precision leveling base, and the angle of the vertical rotating part of the tripod head is set to be an initialized default angle; shooting the two coordinate grid plates by using image acquisition equipment in sequence, and marking the positions corresponding to the centers of the images on the two coordinate grid plates respectively; respectively measuring three-dimensional coordinates of the two mark points by using a total station, and calculating an included angle between the approximate direction of the main optical axis and the horizontal direction; and adjusting the vertical rotating part of the tripod head to be approximately in a horizontal state according to the calculated included angle value.
4. The integrated image capturing device vertical horizontal position calibration method as claimed in claim 1,2 or 3, wherein: the implementation of step 4 is as follows,
firstly, carrying out initial direction control point image acquisition and parameter calculation, wherein the initial direction control point image acquisition and parameter calculation comprises the steps of utilizing a high-precision leveling base to set a horizontal rotating part of a horizontal holder, utilizing a total station and a steel ruler to measure an approximate value of a coordinate of a photographing center of image acquisition equipment, and designating a certain direction as the initial direction of the horizontal rotating part of the holder; shooting the three-dimensional control points of the wall surface of the indoor calibration field in the starting direction by using image acquisition equipment; calculating an included angle between the direction of a main optical axis and the horizontal direction in the vertical direction of the image acquisition equipment by using the shot three-dimensional control points;
secondly, multi-direction control point image acquisition and parameter calculation, including controlling a horizontal rotating part of a tripod head to aim at different directions according to a specified horizontal angle, shooting three-dimensional control points in the calibration center in all directions, and calculating the included angle between a main optical axis and the horizontal direction of the image acquisition equipment in the vertical direction in all horizontal directions by using the three-dimensional control points;
and finally, when the calculated included angle value in each direction is less than a set threshold value, calculating an average value to be used as a final included angle value between the main optical axis direction of the camera and the horizontal direction, and further accurately checking and correcting the horizontal position of the image acquisition equipment in the vertical direction.
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