JP5230354B2 - POSITIONING DEVICE AND CHANGED BUILDING DETECTION DEVICE - Google Patents

Description

  The present invention detects, for example, a position identifying device that identifies the position of a damaged building from image data captured by a video camera mounted on a disaster prevention helicopter, and a building whose ground height is changing from the image data. The present invention relates to a transfer building detection apparatus.

  For example, the position specifying device disclosed in Patent Document 1 below is a straight line extending from the current position of the helicopter toward the image capturing device when the image capturing device mounted on the helicopter captures an object on the ground surface. And an intersection with the ground surface on the three-dimensional geographic data recorded in advance is obtained, and the intersection is specified as the position of the target.

JP-A-8-285590 (FIG. 1)

  Since the conventional position specifying device is configured as described above, the position of the target cannot be specified accurately unless the current position of the helicopter equipped with the photographing device can be accurately detected. There were issues such as.

The present invention has been made to solve the above-described problems, and accurately identifies the position of a target even when the exact current position of an imaging unit mounted on a moving body such as a helicopter is not known. The object is to obtain a location device that can be used.
In addition, the present invention provides a moving building detection apparatus capable of accurately detecting a building whose ground height is changing even when the exact current position of the photographing means mounted on a moving body such as a helicopter is not known. The purpose is to obtain.

  The position specifying device according to the present invention estimates the three-dimensional shape of the photographing range of the photographing means from the ground image data photographed by the photographing means and indicates the ground height at each point in the photographing range from the three-dimensional shape. An area on the ground surface that substantially corresponds to the imaging range is identified from the map data storage unit based on the approximate position of the imaging means measured by the ground height pattern generation unit that generates the pattern and the measurement unit, Elevation point data acquisition means that reads the map data of the area on the ground surface and acquires the elevation point data indicating the elevation of each point from the map data, and the elevation point data acquisition means using the parameters for perspective projection conversion Perspective projection conversion means for performing perspective projection conversion of the acquired elevation point data is provided, and the parameter updating means and the ground height pattern generated by the ground height pattern generation means are transmitted. In correlation with the perspective projection converted elevation point data by the projection conversion means calculates the parameters for the perspective projection transformation becomes maximum is obtained so as to set the parameter to perspective projection conversion means.

  According to the present invention, the three-dimensional shape of the photographing range of the photographing means is estimated from the ground image data photographed by the photographing means, and the ground height pattern indicating the ground height of each point in the photographing range is generated from the three-dimensional shape. An area on the ground surface that substantially corresponds to the shooting range is identified on the basis of the approximate position of the shooting means measured by the ground height pattern generating means and the measuring means, and the above ground surface is determined from the map data storage means. Obtained by the elevation point data acquisition means using the elevation point data acquisition means for acquiring the elevation point data indicating the elevation of each point from the map data and the parameters for perspective projection conversion. A perspective projection conversion means for performing perspective projection conversion of the elevation point data, and the parameter update means generates the ground high pattern generated by the ground high pattern generation means and the perspective projection conversion means. Because it is configured to calculate the parameters for perspective projection conversion that maximizes the correlation with the elevation point data that has been perspective-projected by, and to set the parameters in the perspective projection conversion means, it is mounted on mobile objects such as helicopters. Even if the exact current position of the photographing means being used is not known, there is an effect that the position of the target can be accurately specified.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a position specifying device according to Embodiment 1 of the present invention.
In FIG. 1, a helicopter 1 is a moving body on which a camera 2 and a measuring device 3 are mounted.
The camera 2 is fixed to a pan / tilt head installed in the helicopter 1, and performs a process of photographing the ground from above and outputting ground image data to the arithmetic device 4. The camera 2 constitutes a photographing unit.
The measuring device 3 incorporates a GPS radio wave receiver, an angle sensor, a laser range finder, and the like. The coordinates (x, y, z) indicating the approximate position of the camera 2 at the time of photographing by the camera 2 and the camera 2 Processing for measuring the distance D to the target point on the ground, the body vector (Hu, Hv, Hw), and the optical axis vector (Ou, Ov, Ow) is performed. The measuring device 3 constitutes a measuring means.

However, the coordinates (x, y, z) indicating the approximate position of the camera 2 are given as plane rectangular coordinates obtained by converting latitude, longitude, and altitude obtained from GPS data received by the GPS radio wave receiver.
Also, the airframe vector is given as a unit vector in the lower direction of the airframe from the center of gravity of the helicopter 1, and the optical axis vector is given as a unit vector whose origin is the center of gravity of the helicopter 1.
Since the relative position between the camera 2 and the helicopter 1 and the relative position between the measuring device 3 and the helicopter 1 do not change, the position of the camera 2 can be relatively determined if the measuring device 3 measures its own position.

The arithmetic device 4 collects the ground image data photographed by the camera 2 and the information measured by the measuring device 3, and the elevation point data corresponding to the arbitrary coordinates of the ground image data photographed by the camera 2 (each point To identify the altitude).
Here, each of the ground height pattern generation unit 11, the map data storage unit 12, the elevation point data acquisition unit 13, the perspective projection conversion unit 14, the parameter update unit 15, and the elevation point data mapping unit 16 that are components of the arithmetic device 4. Is configured with dedicated hardware (for example, a semiconductor integrated circuit board on which a CPU is mounted). However, when the arithmetic unit 4 is configured with a computer, the ground high pattern generation unit 11, a program in which processing contents of the elevation point data acquisition unit 13, the perspective projection conversion unit 14, the parameter update unit 15 and the elevation point data mapping unit 16 are described (ground height pattern generation program, elevation point data acquisition program, perspective projection) Conversion program, parameter update program, altitude point data mapping program) are stored in the memory of the computer, and the computer Data the CPU may execute a program stored in the memory.
The display 5 is a display device that displays altitude point data identified by the arithmetic device 4.

The ground height pattern generation unit 11 estimates the three-dimensional shape of the photographing range of the camera 2 from the ground image data photographed by the camera 2, and uses the three-dimensional shape to represent the ground height pattern indicating the ground height of each point in the photographing range. Perform the process to generate. In addition, the ground high pattern production | generation part 11 comprises the ground high pattern production | generation means.
The map data storage unit 12 is a storage medium such as a hard disk that stores map data. The map data storage unit 12 constitutes map data storage means.

The elevation point data acquisition unit 13 specifies an area on the ground surface that substantially corresponds to the shooting range of the camera 2 on the basis of the approximate position of the camera 2 measured by the measuring device 3, and stores the above-mentioned data from the map data storage unit 12. The map data of the area on the ground surface is read, and the elevation point data indicating the elevation of each point is acquired from the map data. The elevation point data acquisition unit 13 constitutes elevation point data acquisition means.
The perspective projection conversion unit 14 performs the perspective projection conversion of the elevation point data acquired by the elevation point data acquisition unit 13 using the parameters for perspective projection conversion updated by the parameter update unit 15. The perspective projection conversion unit 14 constitutes a perspective projection conversion unit.

The parameter update unit 15 calculates a parameter for perspective projection conversion that maximizes the correlation between the ground height pattern generated by the ground height pattern generation unit 11 and the elevation point data subjected to perspective projection conversion by the perspective projection conversion unit 14. Then, a process of setting the parameter in the perspective projection conversion unit 14 is performed. The parameter update unit 15 constitutes parameter update means.
The elevation point data mapping unit 16 includes a man-machine interface such as a keyboard and a mouse. When the user operates the man-machine interface and designates arbitrary coordinates of ground image data photographed by the camera 2, the perspective projection is performed. A process of specifying elevation point data corresponding to the arbitrary coordinates from the elevation point data subjected to perspective projection conversion by the conversion unit 14 is performed. The elevation point data mapping unit 16 constitutes elevation point data mapping means.

Next, the operation will be described.
The camera 2 mounted on the helicopter 1 captures the ground from above and outputs image data on the ground to the arithmetic device 4.
Here, FIG. 2 is an explanatory view showing an example of the ground image data taken by the camera 2, and shows an example in which the ground image data is 512 × 512 pixels.
In particular, (A) is image data taken at time t by the camera 2, and (B) is image data taken at time t-1 (one second before time t).

The measuring device 3 measures the position and orientation of the camera 2, and coordinates (x, y, z) indicating the approximate position of the camera 2 at the time of shooting by the camera 2 and a target point on the ground from the camera 2. Distance D, the airframe vector (Hu, Hv, Hw), and the optical axis vector (Ou, Ov, Ow).
FIG. 3 is an explanatory diagram illustrating an example of a measurement result of the measurement device 3.
In the first embodiment, the measuring device 3 measures the coordinates (x, y, z) indicating the approximate position of the camera 2 by using a built-in GPS radio wave receiver, and the ground target from the camera 2 is measured. The distance D to the point is measured using the built-in laser range finder, and the built-in angle sensor is used for the body vector (Hu, Hv, Hw) and the optical axis vector (Ou, Ov, Ow). It is measured using.

Map data is recorded in advance in the map data storage unit 12 of the arithmetic device 4.
The map data recorded in the map data storage unit 12 includes data indicating the shape of the building and the ID of the building as shown in FIG. 4A, and the ID of the building as shown in FIG. 4B. It consists of a table that shows the correspondence of ground clearance.

Upon receiving the image data at time t and the image data at time t-1 from the camera 2, the ground height pattern generation unit 11 of the arithmetic device 4 performs, for example, stereo image processing on the image data. Thus, the three-dimensional shape of the shooting range of the camera 2 is estimated.
Note that stereo image processing is generally well-known computer processing, and therefore description thereof is omitted here.
For example, “Kenya Kanaya, Mishima et al., 3D reconstruction from two images with uncalibrated camera and its reliability evaluation, IPSJ Transactions on Computer Vision and Image Media, Vol. 42, No. SIG 6 (CVIM 2) (2001), pp. 1-8 "and the like, stereo image processing is disclosed.

When the three-dimensional shape of the shooting range of the camera 2 is estimated, the ground height pattern generation unit 11 generates a ground height pattern indicating the ground height of each point in the shooting range from the three-dimensional shape.
That is, the ground height pattern generation unit 11 identifies the ground height at each point in the shooting range from the three-dimensional shape of the shooting range, and quantizes the ground height at each point as, for example, a 33 × 33 two-dimensional array.
Then, as shown in FIG. 5, the ground level pattern generation unit 11 generates a ground level pattern in which each point has a gray value proportional to the ground level after quantization.
In the example of FIG. 5, the shooting range is a range of (−16 to +16) × (−16 to +16), and a point of 33 × 33 = 1089 is represented. Various patterns at each point indicate the range of ground clearance.

The elevation point data acquisition unit 13 specifies a region on the ground surface that roughly corresponds to the shooting range of the camera 2 with reference to the position and orientation of the camera 2 measured by the measuring device 3.
That is, the altitude point data acquisition unit 13 refers to the measurement result of the measurement device 3 in FIG. 3, and the ground surface reference coordinates (coordinates on the ground surface corresponding to the central portion of the image data output from the camera 2). Gx, Gy) is calculated.
Here, FIG. 6 shows coordinates (x, y, z) indicating the approximate position of the camera 2, a ground surface distance D (a distance from the camera 2 to a target point on the ground), and an airframe vector (Hu, Hv, Hw). And an optical axis vector (Ou, Ov, Ow) and the ground surface reference coordinates (Gx, Gy).
The UVW coordinate system showing the airframe vector (Hu, Hv, Hw) and the optical axis vector (Ou, Ov, Ow) is a right hand with the U direction from the origin to the north and the W axis from the origin to the nadir. Coordinate system.

The ground surface reference coordinates (Gx, Gy) are calculated from the following formulas (1) and (2).
Gx = x + Ou × D (1)
Gy = y + Ov × D (2)
When the altitude point data acquisition unit 13 calculates the ground surface reference coordinates (Gx, Gy), the camera 2 captures a range of 200 m from the ground surface reference coordinates (Gx, Gy) to the east, west, south, and north, respectively. Identify the area on the ground surface that roughly corresponds to the range.

When the altitude point data acquisition unit 13 specifies an area on the ground surface that roughly corresponds to the shooting range of the camera 2, the altitude point data acquisition unit 13 reads the map data of the area on the ground surface from the map data storage unit 12, Elevation point data indicating the altitude of the is acquired.
That is, the elevation point data acquisition unit 13 reads map data in a range of 200 m from the map data storage unit 12 to the east, west, south, and north, respectively, and quantizes the map data with a resolution of 10 m as shown in FIG. A three-dimensional point group (elevation point data) in which each point after conversion has a gray value proportional to the altitude is generated.
In the example of FIG. 7, 41 × 41 = 1681 points are represented in the range of (−200 to +200) × (−200 to +200). Various patterns at each point indicate the range of elevation.
Here, for convenience of explanation, the altitude is assumed as data in a right-handed coordinate system in which the ground surface reference coordinates are the origin (0, 0, 0), and the X axis and the Y axis are parallel to the X axis and the Y axis, respectively, of plane rectangular coordinates Point data is normalized and used.

When the elevation point data acquisition unit 13 acquires the elevation point data, the perspective projection conversion unit 14 performs the perspective projection conversion of the elevation point data using the parameters for perspective projection conversion updated by the parameter update unit 15. .
Expressions (3) and (4) below are expressions of perspective projection conversion by the perspective projection conversion unit 14, and in Expressions (3) and (4), six parameters (X coordinate, Y coordinate of the perspective projection conversion camera, The perspective projection transformation is defined by the Z coordinate, the rotation angle around the X axis of the elevation point data, the rotation angle around the Y axis, and the rotation angle around the Z axis) as parameters.
The coordinates of the i-th elevation point data are (x _i , y _i , z _i ), and the X-value, Y-value, and Z-value of the perspective projection conversion camera are C _x , C _y , C _z , and elevation point data, respectively. The rotation angle around the X axis, the rotation angle around the Y axis, and the rotation angle around the Z axis are ω, φ, and κ, respectively.

ただし、ｆは透視投影変換用カメラの焦点距離、ｘ''_iとｙ''_iは透視投影変換後の座標である。

Here, f is a focal length of the perspective projection conversion camera, and x ″ _i and y ″ _i are coordinates after the perspective projection conversion.

8, 9 and 10 are explanatory diagrams showing an example of perspective projection conversion for the elevation point data of FIG.
The initial parameter for perspective projection conversion used by the perspective projection conversion unit 14 is given based on the numerical values of FIG.
That is, the approximate position (x, y, z) of the camera 2, the distance D from the camera 2 to the target point, the body vector (Hu, Hv, Hw), and the optical axis vector (Ou, Ov, Ow) are expressed by the following formula ( By substituting into 5) to (12), parameters (Cx, Cy, Cz), ω, φ, κ for perspective projection conversion are calculated (when the optical axis vector is in the first quadrant of the UV plane).

When the ground height pattern generation unit 11 generates the ground height pattern and the perspective projection conversion unit 14 performs perspective projection conversion of the elevation point data, the parameter update unit 15 performs elevation projection and elevation point data after the perspective projection conversion. The parameter for perspective projection conversion that maximizes the correlation with is calculated and set in the perspective projection conversion unit 14.
The calculation of the parameters for perspective projection conversion that maximizes the correlation is to search for the parameters for perspective projection conversion that maximizes the correlation, for example, by performing correlation evaluation using a known algorithm such as a local search method. .
That is, the parameter setting for the perspective projection conversion unit 14 by the parameter update unit 15 and the perspective projection conversion by the perspective projection conversion unit 14 are repeatedly executed to search for a parameter for perspective projection conversion that maximizes the correlation. Note that the local search method is a widely known method, and thus the description thereof is omitted here.
FIG. 11 is an explanatory diagram showing an example of the perspective projection conversion result of the elevation point data when the parameter for perspective projection conversion that maximizes the correlation is used.

When the user operates the man-machine interface and designates arbitrary coordinates of the ground image data photographed by the camera 2, the elevation point data mapping unit 16 converts the elevation point data obtained by the perspective projection conversion by the perspective projection conversion unit 14. Elevation point data corresponding to the arbitrary coordinates is specified from the inside.
For example, in the image data of FIG. 4A, the points (153, 165) on the IX-IY coordinates as shown in FIG. 12A are the PX-PY of FIG. Since it corresponds to the point (−3, 2) on the coordinates, the elevation point data of the point (−3, 2) is specified. Further, since it corresponds to the elevation point data of the point (−70, 50) on the XY coordinates in FIG. 7, the elevation point data of the point (−70, 50) is specified.
Further, this altitude point data can be traced to correspond to the building whose building ID is “1002” in FIG.
When the elevation point data mapping unit 16 specifies the elevation point data corresponding to the arbitrary coordinates, the elevation point data is clearly displayed on the display 5.
With the above process, it is possible to specify a building corresponding to an arbitrary coordinate of image data taken from the sky.

  As apparent from the above, according to the first embodiment, the three-dimensional shape of the photographing range of the camera 2 is estimated from the ground image data photographed by the camera 2, and each point in the photographing range is estimated from the three-dimensional shape. An area on the ground surface that substantially corresponds to the shooting range is identified with reference to the approximate position of the camera 2 measured by the measurement device 3 and the ground height pattern generation unit 11 that generates the ground height pattern indicating the ground height. Then, the map data storage unit 12 reads the map data of the area on the ground surface, and acquires the elevation point data acquisition unit 13 for acquiring the elevation point data indicating the elevation of each point from the map data, and for perspective projection conversion. A perspective projection conversion unit 14 that performs perspective projection conversion of the elevation point data acquired by the elevation point data acquisition unit 13 using the parameters is provided, and the parameter update unit 15 is the ground height pattern generation unit 1. Calculates a parameter for perspective projection conversion that maximizes the correlation between the ground height pattern generated by the above and the elevation point data subjected to the perspective projection conversion by the perspective projection conversion unit 14, and sets the parameter in the perspective projection conversion unit 14 Since it comprised so, even when the exact present position of the camera 2 mounted in the helicopter 1 is not known, there exists an effect which can pinpoint the position of a target object correctly.

Embodiment 2. FIG.
FIG. 13 is a block diagram showing a position specifying device (moving building detection device) according to Embodiment 2 of the present invention. In the figure, the same reference numerals as those in FIG.
The transferred building detection unit 17 specifies the elevation point data corresponding to the ground height pattern generated by the ground height pattern generation unit 11 from the elevation point data subjected to the perspective projection conversion by the perspective projection conversion unit 14, and determines the elevation. The elevation point data before the point data is subjected to perspective projection conversion (elevation point data acquired by the elevation point data acquisition unit 13) is specified, and the elevation point data before the perspective projection conversion is compared with the ground height pattern. Execute the process to detect buildings where the ground clearance is changing. In addition, the transfer building detection part 17 comprises the transfer building detection means.

Next, the operation will be described.
Similarly to the first embodiment, the transfer building detection unit 17 generates a perspective projection when the ground height pattern generation unit 11 generates a ground height pattern and the perspective projection conversion unit 14 performs perspective projection conversion of the elevation point data. Elevation point data corresponding to the ground height pattern generated by the ground height pattern generation unit 11 is specified from the elevation point data subjected to perspective projection conversion by the conversion unit 14.
For example, the elevation point data after perspective projection conversion of the building ID “1002” in the image data of FIG. 4A specified by the elevation point data mapping unit 16 is the point (−3, 2) of FIG. The elevation point data of the point (−3, 2) in FIG. 12B corresponds to the point (−3, 2) on the ground height pattern RX-RY coordinate in FIG. 5.
Therefore, in this example, the elevation point data after perspective projection conversion corresponding to the ground height pattern of the point (−3, 2) in FIG. 5 is the elevation point data of the point (−3, 2) in FIG. To be identified.

When the transferred building detection unit 17 specifies the elevation point data corresponding to the ground height pattern generated by the ground height pattern generation unit 11, the elevation point data (elevation point data acquisition) before the elevation point data is subjected to perspective projection conversion. The elevation point data of FIG. 7 acquired by the unit 13) is specified.
Since the elevation point data in FIG. 7 includes the information of the table constituting the map data in FIG. 4B, 38 m can be acquired as the ground height of the building with the building ID “1002”.
On the other hand, since the ground height pattern in FIG. 5 indicates the ground height at each point estimated from the image data of the camera 2, “35 m or more” can be obtained as the estimated ground height of the building with the building ID “1002”. .

The transfer building detection unit 17 calculates the estimated ground height of the building with the building ID “1002” obtained from the ground height pattern in FIG. 5 and the ground height of the building with the building ID “1002” obtained from the elevation point data in FIG. In comparison, it is detected whether the ground height of the building with the building ID “1002” has changed.
Here, the detection of whether or not the ground height of the building with the building ID “1002” has changed has been shown, but whether or not the ground height has changed for each building within the shooting range of the camera 2 is shown. By detecting, it is possible to detect a building where the ground height is increasing or a building where the ground height is decreasing.

  As is apparent from the above, according to the second embodiment, the transferred building detection unit 17 is generated by the ground height pattern generation unit 11 from the elevation point data subjected to the perspective projection conversion by the perspective projection conversion unit 14. The elevation point data corresponding to the above-mentioned ground height pattern is identified, the elevation point data before the elevation point data is subjected to perspective projection conversion is identified, and the elevation point data before the perspective projection transformation is compared with the ground height pattern. Because the building where the ground height is changing is detected, even if the exact current position of the camera 2 mounted on the helicopter 1 is not known, the building where the ground height is changing is accurately detected. There is an effect that can be detected.

Embodiment 3 FIG.
In Embodiments 1 and 2 described above, the elevation point data acquisition unit 13 acquires the elevation point data indicating the elevation of each point from the map data. Among the elevation point data included in the map data, You may make it acquire only the elevation point data whose importance is more than a predetermined value.
Specifically, it is as follows.

In the example of FIG. 7 showing the elevation point data acquired by the elevation point data acquisition unit 13, the number of elevation points is 41 × 41 = 1688.
The perspective projection conversion unit 14 has importance defined in the order of buildings with the highest ground height. For example, if the elevation point data having an importance level equal to or higher than a predetermined value is elevation point data having an elevation level of 15 m or higher, Of the elevation point data included in the map data, only elevation point data having an elevation of 15 m or higher is acquired.
FIG. 14 is an explanatory diagram showing an example of altitude point data having an altitude of 15 m or more.
In the example of FIG. 14, the number of elevation points is reduced to 530 points.

  As apparent from the above, according to the third embodiment, the elevation point data included in the map data is configured to acquire only the elevation point data having an importance level equal to or higher than the predetermined value. The processing amount of the perspective projection conversion in the projection conversion unit 14 is reduced. As a result, there is an effect that the position can be specified and the building can be detected at high speed.

Embodiment 4 FIG.
Hereinafter, modified examples of the first to third embodiments will be described.
<Modification 1>
In the first embodiment, as information for specifying the position and orientation of the camera 2, the measurement device 3 has measured the latitude, longitude, altitude, roll angle, pitch angle, and yaw angle. You may make it measure the mounting angle (pan angle / tilt angle) of the pan head which is fixing.
Thereby, the shooting direction of the camera 2 is not fixed, and the present invention can be applied even when the shooting direction changes.

<Modification 2>
In the first embodiment, the altitude point data acquisition unit 13 quantizes the map data at a resolution of 10 m. However, the quantization resolution is not limited to 10 m, and is fine, for example, 5 m or 1 m. You may make it quantize with the resolution.
As described above, if quantization is performed with a fine resolution, it is possible to specify the position of a small-scale building in which it is difficult to specify a position due to lack of information at a resolution of 10 m.

<Modification 3>
In the first embodiment, the perspective projection conversion unit 14 uses the X, Y, and Z coordinates of the perspective projection conversion camera as the six parameters for perspective projection conversion, and the rotation angle around the X axis of the elevation point data. , The rotation angle around the Y axis and the rotation angle around the Z axis have been shown, but as the six parameters for perspective projection conversion, the X coordinate, Y coordinate, Z coordinate and roll of the perspective projection conversion camera An angle, a pitch angle, and a yaw angle may be used.

<Modification 4>
In the first embodiment, the laser range finder built in the measuring device 3 is used to measure the distance D from the camera 2 to the target point on the ground, but the camera 2 is used without using the laser range finder. The distance D from the camera 2 to the target point on the ground may be calculated with reference to the image data photographed by the above.
FIG. 15 is an explanatory diagram showing a method for calculating the distance D from the camera 2 to the target point on the ground from the image data photographed by the camera 2 and the measurement data of the measuring device 3.

The approximate value of the distance D is calculated by the following equation (13).

However, (X _t , Y _t , Z _t ) are the coordinates of the camera 2 at time t, (X _t−1 , Y _t−1 , Z _t−1 ) are the coordinates of the camera 2 at time t−1, and m is moving distance from the time t-1 on the camera projection surface point a on the ground surface (model) to time t, f is the focal length of the camera _{2, (e x, e y} , e z) camera 2 , Φ is the angle formed by the movement vector of the camera 2 and the optical axis vector, and M is the movement distance of the camera 2 from time t−1 to time t.
Note that the point A is a point of a structure near the center of the image in the image data taken at time t.

<Modification 4>
In Embodiment 3 above, as the importance of elevation point data, the importance is defined in the order of buildings with the highest ground height. However, as the importance of elevation point data, the building area, seismic strength, The complexity or simplicity of the superstructure may be defined.

It is a block diagram which shows the position specific apparatus by Embodiment 1 of this invention. It is explanatory drawing which shows an example of the ground image data image | photographed with the camera. It is explanatory drawing which shows an example of the measurement result of the measuring device. It is explanatory drawing which shows an example of the map data currently recorded on the map data storage part. It is explanatory drawing which shows an example of the ground high pattern produced | generated by the ground high pattern production | generation part. The coordinates (x, y, z) indicating the approximate position of the camera 2, the distance D to the ground surface (the distance from the camera 2 to the target point on the ground), the body vector (Hu, Hv, Hw), and the optical axis vector ( It is explanatory drawing which shows the relationship between (Ou, Ov, Ow) and ground surface reference coordinates (Gx, Gy). It is explanatory drawing which shows an example of the altitude point data acquired by the altitude point data acquisition part. It is explanatory drawing which shows the example of perspective projection conversion with respect to the elevation point data of FIG. It is explanatory drawing which shows the example of perspective projection conversion with respect to the elevation point data of FIG. It is explanatory drawing which shows the example of perspective projection conversion with respect to the elevation point data of FIG. It is explanatory drawing which shows an example of the perspective projection conversion result of the elevation point data when the parameter for perspective projection conversion that maximizes the correlation is used. It is explanatory drawing which shows an example of the altitude point data after image data and perspective projection conversion. It is a block diagram which shows the position specification apparatus (change building detection apparatus) by Embodiment 2 of this invention. It is explanatory drawing which shows an example of the elevation point data whose elevation is 15 m or more. It is explanatory drawing which shows the method of calculating the distance D from the camera 2 to the target point on the ground from the image data image | photographed with the camera 2, and the measurement data of the measuring device 3. FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Helicopter, 2 Cameras, 3 Measuring apparatus, 4 Arithmetic unit, 11 Ground height pattern production | generation part (ground height pattern production | generation means), 12 Map data storage part (map data storage means), 13 Elevation point data acquisition part (elevation point data Acquisition unit), 14 perspective projection conversion unit (perspective projection conversion unit), 15 parameter update unit (parameter update unit), 16 elevation point data mapping unit (elevation point data mapping unit), 17 changed building detection unit (changed building detection unit) ).

Claims (4)

  An imaging means for imaging the ground from above, a measuring means for measuring the approximate position of the imaging means, and estimating the three-dimensional shape of the imaging range of the imaging means from the ground image data captured by the imaging means, The ground height pattern generating means for generating the ground height pattern indicating the ground height at each point in the shooting range from the three-dimensional shape, the map data storage means storing map data, and the measurement means measured by the measuring means Based on the approximate position of the photographing means, an area on the ground surface substantially corresponding to the photographing range is specified, map data of the area on the ground surface is read from the map data storage means, and from the map data The altitude point data acquiring means for acquiring the altitude point data indicating the altitude of each point and the altitude point data acquiring means using the parameters for perspective projection conversion. The perspective projection conversion means for performing perspective projection conversion of point data, the above-described maximum correlation between the ground height pattern generated by the ground height pattern generation means and the elevation point data subjected to the perspective projection conversion by the perspective projection conversion means A parameter updating unit that calculates a parameter for perspective projection conversion and sets the parameter in the perspective projection conversion unit, and an altitude point data that has been subjected to perspective projection conversion by the perspective projection conversion unit, is captured by the imaging unit. A position specifying device comprising: elevation point data mapping means for specifying elevation point data corresponding to arbitrary coordinates of the obtained ground image data.   The elevation point data corresponding to the ground height pattern generated by the ground height pattern generation means is identified from the elevation point data that has been perspective projection transformed by the perspective projection transformation means, and the elevation point data is perspective projection transformed. Identifying the previous elevation point data, comparing the elevation point data before the perspective projection conversion with the above ground height pattern, and providing a moving building detection means for detecting a building whose ground height is changing. The position specifying device according to claim 1, wherein   3. The position specification according to claim 1, wherein the elevation point data acquisition means acquires only elevation point data having an importance level equal to or higher than a predetermined value from the elevation point data included in the map data. apparatus.   An imaging means for imaging the ground from above, a measuring means for measuring the approximate position of the imaging means, and estimating the three-dimensional shape of the imaging range of the imaging means from the ground image data captured by the imaging means, The ground height pattern generating means for generating the ground height pattern indicating the ground height at each point in the shooting range from the three-dimensional shape, the map data storage means storing map data, and the measurement means measured by the measuring means Based on the approximate position of the photographing means, an area on the ground surface substantially corresponding to the photographing range is specified, map data of the area on the ground surface is read from the map data storage means, and from the map data The altitude point data acquiring means for acquiring the altitude point data indicating the altitude of each point and the altitude point data acquiring means using the parameters for perspective projection conversion. The perspective projection conversion means for performing perspective projection conversion of point data, the above-described maximum correlation between the ground height pattern generated by the ground height pattern generation means and the elevation point data subjected to the perspective projection conversion by the perspective projection conversion means A parameter update unit that calculates parameters for perspective projection conversion and sets the parameters in the perspective projection conversion unit, and generates the ground height pattern from the elevation point data that has been perspective projection converted by the perspective projection conversion unit. The elevation point data corresponding to the ground height pattern generated by the means is specified, the elevation point data before the elevation point data is subjected to perspective projection conversion, the elevation point data before the perspective projection conversion is specified, and A changed building detection apparatus comprising: changed building detection means for detecting a building whose ground height is changing by comparing the above ground height patterns.

Images