JP2017026552A - Three-dimensional measurement device, three-dimensional measurement method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress occlusion in stereo photographic surveying using a camera which moves to an object, and achieves efficiency of photographing, and reduction of calculation cost, with well balance.SOLUTION: Image acquisition means 20 sets image acquisition zones and dormant zones alternately, along a path of a camera 8, and acquires plural images which are sequentially photographed in the image acquisition zones. Coordinate calculation means 22 performs stereo photographic surveying using the images which were photographed in the same image acquisition zone, for calculating a three-dimensional coordinate. A length of the dormant zone, in which image acquisition is suspended between a preceding image acquisition zone and a subsequent image acquisition zone, is set so that an overlapped photographing area in the images in the preceding image acquisition zone and an overlapped photographing area in the images in the subsequent image acquisition zone are connected with each other, and a length of the image acquisition zone is shorter than the length of the dormant zone.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an apparatus, a method, and a program for performing stereo photogrammetry using images photographed from different photographing positions by a camera that moves with respect to an object and measuring the three-dimensional coordinates of the object.

  Stereo photogrammetry is known as a technique for obtaining the three-dimensional coordinates of a point on an object. In stereo photogrammetry, three-dimensional coordinates are calculated based on the principle of triangulation for corresponding points appearing in common in two images taken from cameras arranged at different positions (viewpoints). For example, a stereo photogrammetry technique is used to obtain the shape of a feature from an aerial photograph taken by a camera mounted on a satellite, an aircraft, or the like.

  Here, due to the shape of an object to be measured or an obstacle, an image may have a shadowed portion when viewed from the viewpoint of photographing it, and the coordinates of the portion cannot be acquired by stereo photogrammetry. This phenomenon is called occlusion. Occlusion can be reduced by shortening the distance (baseline length) between the positions of the cameras that take two images and reducing the parallax between the two images. In addition, by using the short base line, changes in the geometric shape of the object and the luminance state between images are reduced, and matching of corresponding points is facilitated.

Japanese Patent No. 5311016

  In short baseline stereo photogrammetry, the time required for the platform with the camera to move the baseline length is reduced. In recent years, it is possible to perform aerial survey using a multicopter type unmanned aerial vehicle (UAV). For example, when stereo photogrammetry with a base line length of 0.5 meters is continuously performed while flying a UAV at a speed of 5 meters per second, photography requires high-speed continuous shooting at 10 frames / second. On the other hand, photogrammetry requires high-resolution photos. Since the data size of a high-resolution image increases, it is difficult to maintain high-speed continuous shooting with a normal digital still camera. That is, it is difficult to continuously acquire images for stereo photogrammetry of a short baseline. Here, if the speed of the platform is lowered, the efficiency of the photographing work is lowered. In addition, since the number of images obtained by photographing for each baseline length increases as the baseline length decreases, continuously performing stereo photogrammetry of the short baseline increases the processing load and the processing time.

  The present invention has been made to solve the above-described problems, and a three-dimensional measurement apparatus capable of achieving a balanced balance between stereo photogrammetry shooting efficiency and calculation cost reduction while suppressing occlusion, It is an object to provide a three-dimensional measurement method and program.

  (1) A three-dimensional measuring apparatus according to the present invention performs stereo photogrammetry using images taken from different photographing positions by a camera that moves with respect to an object, and measures the three-dimensional coordinates of corresponding points of the object. The image acquisition unit is the same as the image acquisition unit that sets an image acquisition interval alternately with a pause interval along the path of the camera and acquires a plurality of the images that are sequentially captured in the image acquisition interval. Coordinate calculation means for calculating the three-dimensional coordinates by the stereo photogrammetry using the images taken in the section, and the image between the preceding image acquisition section and the subsequent image acquisition section The length of the pause interval during which acquisition is paused is such that the overlapping shooting region between the images in the preceding image acquisition interval and the overlapping shooting region between the images in the subsequent image acquisition interval are connected to each other. Is urchin set, and the length of the image acquisition interval is set shorter than the idle period.

  (2) In the three-dimensional measurement apparatus according to (1), the image acquisition unit acquires the images at three or more photographing positions in the image acquisition section, and performs multi-baseline stereo photogrammetry. To do. As a result, the height accuracy and robustness of the three-dimensional point group can be improved.

  (3) The three-dimensional measuring apparatus according to (1) and (2) further performs the stereo photogrammetry using the image in the preceding image acquisition section and the image in the subsequent image acquisition section. Coordinate correcting means for correcting the position in the depth direction in the stereo photogrammetry of the three-dimensional coordinates calculated by the coordinate calculating means on the basis of the obtained three-dimensional coordinates may be provided.

  (4) In the three-dimensional measurement method according to the present invention, stereo photogrammetry is performed using images photographed from different photographing positions by a camera moving with respect to the object, and the three-dimensional coordinates of corresponding points of the object are measured. An image acquisition step of setting an image acquisition interval alternately with a pause interval along the path of the camera, and acquiring a plurality of the images sequentially photographed in the image acquisition interval; and each image acquisition A coordinate calculation step of calculating the three-dimensional coordinates by the stereo photogrammetry using the images in the section, and pauses the acquisition of the image between the preceding image acquisition section and the subsequent image acquisition section. The length of the pause section is such that the overlapping shooting area of the images in the preceding image acquisition section and the overlapping shooting area of the images in the subsequent image acquisition section are connected to each other. It is set, and the length of the image acquisition interval is set shorter than the idle period.

  (5) The program according to the present invention is a computer that performs a stereo photogrammetry using images photographed from different photographing positions by a camera that moves with respect to an object and measures the three-dimensional coordinates of corresponding points of the object. A program for causing the computer to set an image acquisition interval alternately with a pause interval along the path of the camera, and to acquire a plurality of the images sequentially captured in the image acquisition interval And functioning as an image acquisition means and a coordinate calculation means for calculating the three-dimensional coordinates by the stereo photogrammetry using the images in the image acquisition sections, and the preceding image acquisition section and the subsequent image acquisition section The length of the pause interval in which the acquisition of the image is paused in between is the overlapping shooting area of the images in the preceding image acquisition interval and the subsequent image acquisition zone. Wherein the image and the overlapped imaging region between the set so as to be connected to each other, and the length of the image acquisition interval is set shorter than the idle period in.

  According to the present invention, in stereo photogrammetry, it is possible to improve the efficiency of shooting while reducing occlusion and further reduce the calculation cost in a well-balanced manner.

It is a block diagram which shows the schematic structure of the three-dimensional measuring apparatus which concerns on embodiment of this invention. It is a schematic diagram explaining the principle of a stereo photogrammetry. It is a schematic diagram which shows the imaging | photography point and imaging | photography range in embodiment of this invention. It is a general | schematic flowchart of the three-dimensional measuring method in embodiment of this invention. It is a schematic diagram explaining the correction process of the height error of a three-dimensional point group. It is a schematic diagram which shows the other example of the imaging | photography point in embodiment of this invention.

  Hereinafter, a three-dimensional measurement apparatus 2 according to an embodiment of the present invention (hereinafter referred to as an embodiment) will be described with reference to the drawings.

  FIG. 1 is a block diagram showing a schematic configuration of the three-dimensional measuring apparatus 2, and the three-dimensional measuring apparatus 2 includes an arithmetic processing device 4 and a storage device 6. In the present embodiment, the three-dimensional measurement apparatus 2 is mounted on a multicopter type UAV and includes a camera 8 and a GNSS / IMU (Global Navigation Satellite System: Inertial Measurement Unit) 10. Although the UAV flight motor and its control mechanism are not shown in FIG. 1, they are basically constituted by conventional techniques. Incidentally, the UAV may be configured to be remotely controlled by radio, or may be configured to automatically fly according to a flight program stored in the storage device 6 in advance. In addition to the UAV, the three-dimensional measuring apparatus 2 may be mounted on a mobile body such as an aircraft or an MMS (Mobile Mapping System).

  The arithmetic processing unit 4 is constructed using, for example, a computer and a program executed on the computer. A CPU (Central Processing Unit) of the computer constitutes the arithmetic processing unit 4 and functions as an image acquisition unit 20, a coordinate calculation unit 22, and a coordinate correction unit 24 described later.

  The storage device 6 is composed of a semiconductor memory, a hard disk, or the like. The storage device 6 stores a program for causing the arithmetic processing unit 4 to function as the image acquisition unit 20, the coordinate calculation unit 22, and the coordinate correction unit 24, other programs, and various data necessary for the processing of this system. For example, the storage device 6 stores an image photographed by the camera 8, a coordinate of a three-dimensional point group that is a measurement result by the three-dimensional measurement device 2, and the like.

  The camera 8 takes a digital image. In this embodiment, the measurement target is a feature, and the camera 8 is mounted on the UAV with the shooting direction facing downward so that the feature can be shot from the UAV in flight. For example, the direction of the optical axis 15 of the camera 8 is set to be a vertical direction when the UAV is in a horizontal state. The viewing angle θ of the camera 8 can be selected according to the height difference of the features in the measurement target range. For example, in general aerial photogrammetry, a wide-angle camera with θ of about 90 ° is used, and θ can be set to about 120 ° when measuring an area with a small difference in elevation, such as a flat ground. When measuring a forest area or an area where a high-rise structure exists, θ can be about 60 °. The camera 8 outputs the captured image data to the arithmetic processing device 4. For example, the arithmetic processing device 4 stores the image data input from the camera 8 in the storage device 6.

  The GNSS / IMU 10 receives a signal from a satellite, measures the acceleration / angular velocity of the UAV by the IMU, generates GNSS / IMU data representing the position / attitude of the UAV based on them, and outputs it to the arithmetic processing unit 4 To do. For example, the arithmetic processing device 4 stores the GNSS / IMU data at the time when the image data is acquired in the storage device 6 in association with the image data.

The image acquisition means 20 instructs the camera 8 to take a shooting timing and acquires image data at that timing. As will be described later, the image acquisition means 20 alternately sets the image acquisition section and the pause section along the path of the camera 8 (or the flight path of the UAV). In the image acquisition section, the image acquisition means 20 instructs the camera 8 to perform shooting with a relatively short shooting position interval _BS , and acquires a plurality of images. On the other hand, the pause section is a section in which shooting is not performed, and can be defined as a section from the last shooting position in the preceding image acquisition section to the first shooting position in the subsequent image acquisition section. The pause section is set longer than the image acquisition section, while the overlapping shooting area between images in the preceding image acquisition section and the overlapping shooting area between images in the subsequent image acquisition section are connected to each other.

  The coordinate calculation means 22 calculates the three-dimensional coordinates of the object by stereo photogrammetry using images taken in the same image acquisition section, and obtains a three-dimensional point group distributed according to the shape of the object. . Further, prior to stereo matching, the coordinate calculation means 22 uses the SfM (Structure from Motion) technique to determine the correct position and orientation of the camera. At that time, GNSS / IMU data can be used as an initial value.

  The coordinate correction unit 24 calculates the three-dimensional coordinates of the object by stereo photogrammetry as in the coordinate calculation unit 22, but the coordinate calculation unit 22 performs stereo matching between images in the same image acquisition section. The coordinate correction unit 24 performs stereo matching between images in different image acquisition sections. That is, the coordinate correction unit 24 calculates three-dimensional coordinates using the image of the preceding image acquisition section and the image of the subsequent image acquisition section. The coordinate correction unit 24 corrects the coordinates of the three-dimensional point group calculated by the coordinate calculation unit 22 based on the calculated three-dimensional coordinates. Specifically, the coordinate correction unit 24 corrects the position of the three-dimensional point group in the depth direction in stereo photogrammetry, that is, the height in this embodiment.

  FIG. 2 is a schematic diagram for explaining the principle of stereo photogrammetry. The coordinates of the three-dimensional space are represented by an orthogonal coordinate system XYZ, the Z axis is the height direction, the XY plane is the horizontal plane, and the UAV flight direction, that is, the direction along the base line is the Y axis. FIG. 2 shows the positional relationship in the XZ plane, with the vertical direction corresponding to the Z axis and the horizontal direction corresponding to the X axis.

In FIG. 2, points O ₁ and O ₂ are viewpoint positions (camera positions), respectively. Here, in order to simplify the description, the case where the UAV maintains a horizontal posture and flies horizontally will be described. In this case, the points O ₁ and O ₂ are at the same height, and the optical axis of the camera 8 faces vertically downward in both the viewpoints O ₁ and O ₂ . I ₁ and I ₂ represent the projection planes of the camera 8 corresponding to the viewpoints O ₁ and O ₂ , and each projection plane is at a focal distance f from the viewpoint. Coordinate calculation unit 22, an image together taken on the projection surface _I 1, _{I 2} and stereo matching process, obtaining an image _P 1, _{P 2} in the projection plane _I 1, _{I 2} of the corresponding points M. The two-dimensional coordinates on the images P ₁ and P ₂ are (ζ ₁ , η ₁ ) and (ζ ₂ , η ₂ ), respectively. Here, assuming that the coordinate axes of the ζ and η coordinates are the same as the X and Y axes, ζ ₁ −ζ ₂ is a parallax in the X axis direction between the viewpoints O ₁ and O ₂ with respect to the point M. Using this parallax, a shooting distance H that is a distance in the Z direction from the base line O ₁ O ₂ of the point M is calculated by the following equation, for example. B is the length of the base line O ₁ O ₂ (base line length). Incidentally, since the parallax in the Y-axis direction is zero in principle, η ₁ -η ₂ is also zero.
H = f · B / (ζ ₁ −ζ ₂ ) (1)

Here, if the viewpoint O ₁ is the origin of the XYZ coordinate system, the Z coordinate z _m of the point M is
z _m = −H
It becomes. Furthermore, zeta, by defining the intersection between the origin of the η coordinate projection plane and the optical _axis, x _m, y m is represented by the following formula.
x _m = ζ ₁ · B / (ζ ₁ −ζ ₂ ) (2)
y _m = η ₁ · B / (ζ ₁ −ζ ₂ ) (3)

Incidentally, as described above, the positional relationship shown in FIG. 2 is a simple example. Actually, there is a difference in height between the points O ₁ and O ₂ , and the optical axis may be deviated from the vertical direction. Even in such a case, the coordinate calculation means 22 grasps the positional relationship between the camera 8 and the corresponding point M at each viewpoint from the camera position / posture data by SfM, and uses the epipolar geometry to make a three-dimensional view of the point M. Coordinates can be calculated.

FIG. 3 is a schematic diagram showing a shooting point and a shooting range in the embodiment of the present invention. FIG. 3 shows the positional relationship in the XZ plane, with the vertical direction corresponding to the Z axis (height) and the horizontal direction corresponding to the X axis (horizontal position). O _i (i = 1, 2, 3,...) Is a shooting point. S _i (i = 1, 2, 3,...) Is a shooting range of the camera 8 at O _i .

Here, the interval between the shooting points is not uniform, and a section (image acquisition section R _S ) where two shooting points are arranged at a relatively short distance along the flight path of the UAV, that is, the camera path 30, is sandwiched between them. A relatively long section (pause section R _P ) where there is no shooting point is provided. Image acquisition sections _R 2 two intervals _{B S} of the imaging point _S, when the lengths of the pause interval _{R P} and _{B P, B S, B P is, (B S + B P)} / H, or _B P / H becomes a value (eg, B / H = 0.1-1) corresponding to the baseline ratio (B / H) in the long baseline stereophotogrammetry, and B _S / H is the baseline ratio (B / H) in the short baseline stereophotogrammetry. H) is set to a value corresponding to (for example, B / H <0.1).

Camera 8 at the two imaging points adjacent in the image acquisition sections _{R S} (eg, point _O 1, _{O 2} or point _O 3, _{O 4,)} have a common field of view, for example, coordinate calculation unit 22, O the 3D point group of the feature can be calculated by the stereo photogrammetric at overlapping imaging areas 32a and captured images from the image and O ₂ taken from _1. Similarly, a three-dimensional point group of the feature is obtained in the overlapping photographing region 32b of the photographing points O ₃ and O ₄ .

The length B _P of the pause interval R _P is overlapped imaging region 32a between images in the preceding image acquisition section and the overlapped imaging region 32b between images in the subsequent image acquisition section is set to be connected to each other. For example, in the example shown in FIG. 3, _BP is set so that the overlapping shooting areas 32 a and 32 b have the overlapping area 34. Thereby, the ground surface can be measured without a gap.

Further, the length of the image acquisition section is set shorter than the pause section. Specifically, in the present embodiment, B _S < _BP .

FIG. 4 is a schematic flowchart of a three-dimensional measurement method performed by the three-dimensional measurement apparatus 2. For example, the image acquisition unit 20 detects that the camera 8 has reached the shooting point based on the GNSS data, and instructs the camera 8 to perform shooting. As a result, a plurality of images taken at intervals B _S in the image acquisition section are obtained (step S10).

  The coordinate calculation unit 22 performs corresponding point matching processing on images captured in the same image acquisition section (step S20). Prior to the matching process, the coordinate calculation means 22 obtains the position / orientation of the camera 8 when the image is captured using the SfM method. The coordinate calculation means 22 calculates the three-dimensional coordinates of the corresponding points using epipolar geometry from the two-dimensional coordinates of the corresponding points in the image and the position / orientation of the camera 8 (step S30).

  Here, as the baseline length becomes shorter, the height accuracy of the three-dimensional point group calculated by stereo measurement becomes more susceptible to the parallax error of the corresponding points in the matched image. In this regard, by using a high-accuracy image matching method in step S20, parallax estimation errors in stereo measurement can be reduced. For example, the phase only correlation method can be used as a highly accurate matching method. By reducing the parallax error, the accuracy of the height of the three-dimensional coordinates can be improved in step S30.

Three-dimensional coordinates calculated by the stereo photogrammetric short base length B _S step S30 is stored in the storage device 6.

  The coordinate correction unit 24 corrects the height of the three-dimensional coordinates calculated in step S30 using the three-dimensional coordinates of the corresponding points calculated by the stereo photogrammetry with a long baseline length (step S40). The coordinate correction unit 24 reads, for example, images captured in two image acquisition sections adjacent to each other with the pause section interposed therebetween from the images stored in the storage device 6, and stereo-matches the images in these different image acquisition sections. Processing is performed to calculate the three-dimensional coordinates of the corresponding points. For example, in this process, the coordinates of the corresponding points in the overlapping area 34 in FIG. 3 are obtained.

  The coordinate correction unit 24 corrects the height of the three-dimensional coordinates calculated in step S30 according to the difference between the height calculated in step S30 and the height calculated in step S40 for the same corresponding point ( Step S50).

FIG. 5 is a schematic diagram for explaining the correction process of the height error of the three-dimensional point group by the coordinate correction means 24. FIG. FIG. 5 shows the positional relationship in the XZ plane, with the vertical direction corresponding to the Z axis (height) and the horizontal direction corresponding to the X axis (horizontal position). O _2i−1 , O _2i , and O _{2i + 1} (i is a natural number) are shooting points, and O _2i−1 and O _2i are shooting points adjacent to each other at the interval B _S in the same image acquisition section. _{2i + 1} is a shooting point of an image acquisition section next to O _2i-1 and O _2i . E _2i−1 , E _2i , and E _{2i + 1} are line-of-sight lines from the shooting points O _2i−1 , O _2i , and O _{2i + 1} to the corresponding point M on the object 40, respectively.

Here, a case where an estimation error exists in the position and orientation of the camera 8 at the shooting point O _2i will be described as an example. Due to the error, the line of sight _{E 2i} in photographic point _{O 2i} is offset from the correct line of sight E _'2i. Therefore, the estimated position of the corresponding point M calculated by the stereo photogrammetry at the baseline length B _S regarding the shooting points O _2i-1 and O _2i is shifted to the point M _S. In FIG. 5, a dotted line 42 represents the shape of the object 40 composed of a three-dimensional point group obtained by stereophotogrammetry with a relatively short baseline length B _S like the point M _S. Incidentally, since the error of the line of sight in the stereo photogrammetry of the short baseline can increase the error of the height, the measurement result 42 by the short baseline stereo photogrammetry is shifted in the height direction in FIG. Expressed with lines.

The coordinate correction unit 24 performs, for example, stereo photogrammetry regarding the shooting points O _{2i + 1} and O _2i and calculates the point M _L1 as the estimated position of the corresponding point M. Stereo photogrammetry and photographic point _{O 2i + 1} and _{O 2i,} since the longer base line length from the stereo photogrammetric about photographing points _{O 2i-1, O 2i,} errors of shot point _{O 2i} (or error with the line of sight _{E 2i)} It is difficult to be affected, and the point M _L1 can be expected to have a smaller error in the height direction than the point M _S. Therefore, for example, according to the difference in height between the point M _S and the point M _L1, corrects the measurement result 42 by the short baseline stereo photogrammetry. For example, the height of the three-dimensional point group that is the measurement result 42 is shifted by the height of the point M _L1 with respect to the point M _S , and the corrected measurement result 44 is obtained.

Actually, it is often not easy to know which photographing point has an error. In that case, for example, stereo photogrammetry can be performed for a plurality of sets of shooting points belonging to different image acquisition sections, and correction can be made based on the average value of the results. Specifically, in the example of FIG. 5, in addition to the above-mentioned _ML1 as an estimated position of the corresponding point M, the point _ML2 is calculated by stereo photogrammetry regarding the shooting points _{O2i + 1} and _O2i-1 . Then, the measurement result 42 is corrected with the average value of the difference in height between the points M _S and M _L1 and the difference in height between the points M _S and M _L2 .

FIG. 6 is a schematic diagram showing another example of the shooting point O in the embodiment of the present invention. In the above description, the number n of shooting points set in the image acquisition section has been two, but the number n of shooting points can be three or more as shown in FIG. Multi-baseline stereo photogrammetry can be performed using a plurality of images. Here, the value of n is determined by comprehensively considering the continuous shooting performance of the camera 8, the processing load of multi-baseline stereo photogrammetry in the arithmetic processing unit 4, the required accuracy of the three-dimensional point group to be created, and the like. If the interval between the shooting points is B _S , the length of the image acquisition section R _S is (n−1) B _S.

  The three-dimensional measuring apparatus 2 performs stereo photogrammetry with a short baseline length only in the image acquisition interval, and a pause interval longer than the image acquisition interval is provided between the image acquisition intervals. By shortening the base line length, occlusion is reduced and stereo matching is facilitated. This makes it possible to extract a three-dimensional point group with high density. On the other hand, instead of always performing stereo photogrammetry of short baselines, it is possible to reduce the processing load and shorten the processing time by providing a pause period, making it easier to extract a 3D point cloud It becomes. For example, a three-dimensional point group can be generated in parallel with image shooting.

  2 3D measuring device, 4 arithmetic processing device, 6 storage device, 8 camera, 10 GNSS / IMU, 20 image acquisition means, 22 coordinate calculation means, 24 coordinate correction means.

Claims (5)

A three-dimensional measuring apparatus that performs stereo photogrammetry using images taken from different photographing positions by a camera that moves with respect to an object and measures the three-dimensional coordinates of corresponding points of the object,
An image acquisition unit that sets an image acquisition interval alternately with a pause interval along the path of the camera, and acquires a plurality of the images that are sequentially captured in the image acquisition interval;
Coordinate calculation means for calculating the three-dimensional coordinates by the stereo photogrammetry using the images taken in the same image acquisition section,
The length of the pause interval in which the image acquisition is paused between the preceding image acquisition interval and the subsequent image acquisition interval is the overlapping shooting region between the images in the preceding image acquisition interval and the length in the subsequent image acquisition interval. It is set so that the overlapping shooting areas between images are connected to each other, and the length of the image acquisition section is set shorter than the pause section,
A three-dimensional measuring device characterized by The three-dimensional measurement apparatus according to claim 1,
The image acquisition means acquires the images at three or more shooting positions in the image acquisition section,
Be configured to perform multi-baseline stereo photogrammetry,
A three-dimensional measuring device characterized by In the three-dimensional measurement apparatus according to claim 1 or 2,
The stereo photogrammetry using the image in the preceding image acquisition section and the image in the subsequent image acquisition section is performed, and the 3D calculated by the coordinate calculation means based on the three-dimensional coordinates obtained thereby. Coordinate correction means for correcting the position in the depth direction in the stereo photogrammetry of dimensional coordinates;
A three-dimensional measuring device characterized by A three-dimensional measurement method of performing stereo photogrammetry using images taken from different photographing positions by a camera that moves with respect to an object and measuring the three-dimensional coordinates of corresponding points of the object,
An image acquisition step of setting an image acquisition interval alternately with a pause interval along the path of the camera, and acquiring a plurality of the images sequentially captured in the image acquisition interval;
A coordinate calculation step of calculating the three-dimensional coordinates by the stereo photogrammetry using the images in the image acquisition sections,
The length of the pause interval in which the image acquisition is paused between the preceding image acquisition interval and the subsequent image acquisition interval is the overlapping shooting region between the images in the preceding image acquisition interval and the length in the subsequent image acquisition interval. It is set so that the overlapping shooting areas between images are connected to each other, and the length of the image acquisition section is set shorter than the pause section,
A three-dimensional measurement method characterized by A program for performing a stereo photogrammetry using images photographed from different photographing positions by a camera moving with respect to an object, and causing a computer to perform a process of measuring the three-dimensional coordinates of corresponding points of the object, The computer
An image acquisition unit that sets an image acquisition interval alternately with a pause interval along the path of the camera, and acquires a plurality of the images that are sequentially captured in the image acquisition interval; and
Function as coordinate calculation means for calculating the three-dimensional coordinates by the stereo photogrammetry using the images in the image acquisition sections,
The length of the pause interval in which the image acquisition is paused between the preceding image acquisition interval and the subsequent image acquisition interval is the overlapping shooting region between the images in the preceding image acquisition interval and the length in the subsequent image acquisition interval. It is set so that the overlapping shooting areas between images are connected to each other, and the length of the image acquisition section is set shorter than the pause section,
A program characterized by

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