Method and program for estimating volume of object, computer-readable storage medium having the program stored thereon, and computer having the program installed thereon

Abstract

To provide a method for efficiently estimating a volume of an object based on an image of the object.SOLUTION: A method includes: preparing a first image, a second image, and a third image of an object acquired from a first location, a second location, and a third location, respectively, by using a three-dimensional camera; setting a first occupation region, a second occupation region, and a third occupation region in a quadrangular shape occupying 80% or more and 120% or less of an area of the object in the first to third images, respectively; determining, in each of the first to third images, x-coordinates, y-coordinates, and z-coordinates of each vertex of the first to third occupation regions on a local coordinate system common to the first to third images; constructing a hexahedron that approximates the object in an XYZ global coordinate system that is independent of the x-coordinates, the y-coordinates, and the z-coordinates based on the local coordinates of the first to third occupation regions.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] One embodiment of the present invention relates to a method for estimating the volume of an object, for example, to a method and program for estimating the volume of an object using an image of the object, a computer-readable storage medium having the program stored thereon, and a computer having the program installed thereon. [Background technology]

[0002] There are known methods for estimating the volume of an object using an image of the object. For example, Patent Document 1 discloses a method for estimating the volume of a spherical crop from the radius of the end face, which is half the width of the spherical crop determined from a side image, and the height of the pixel, assuming that the shape of the end face parallel to the horizontal plane of the spherical crop is a circle. Patent Document 2 discloses a method for estimating the volume of an object by projecting a unique pattern onto an object provided with markers and processing images acquired from two locations in this state. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-135275 [Patent Document 2] JP 2011-191131 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of one embodiment of the present invention is to provide a novel method for estimating the volume of an object, or to provide a method for efficiently estimating the volume of an object based on an image of the object. [Means for solving the problem]

[0005] One embodiment of the present invention is a method for estimating the volume of an object, which includes: preparing a first image of the object acquired from a first location, a second image of the object acquired from a second location, and a third image of the object acquired from a third location using a three-dimensional camera; setting a first rectangular occupation area, a second rectangular occupation area, and a third rectangular occupation area each occupying 80% to 120% of the area of ​​the object in the first image, the second image, and the third image, respectively; determining the x-, y-, and z-coordinates of each vertex of the first occupation area, the second occupation area, and the third occupation area in the first image, the second image, and the third image, respectively, on a local coordinate system common to the first image, the second image, and the third image; constructing a hexahedron approximating the object in an XYZ global coordinate system independent of the x-, y-, and z-coordinates based on the local coordinates of the first occupation area, the second occupation area, and the third occupation area; and calculating the volume of the hexahedron. The X-axis, Y-axis, and Z-axis of the XYZ global coordinate system are parallel to the x-axis, y-axis, and z-axis, respectively.

[0006] One embodiment of the present invention is a program for estimating the volume of an object. The program is configured to execute the following: determining the x-, y-, and z-coordinates of each vertex of a first, second, and third occupancy area of ​​a rectangle occupying 80% to 120% of the area of ​​a set object in a first image, a second image, and a third image of the object acquired by a three-dimensional camera at a first point, a second point, and a third point, respectively, on a local coordinate system common to the first image, the second image, and the third image; constructing a hexahedron approximating the object in an XYZ global coordinate system independent of the x-, y-, and z-coordinates based on the local coordinates of the first, second, and third occupancy areas; and calculating the volume of the hexahedron. The X-, Y-, and Z-axes of the XYZ global coordinate system are parallel to the x-, y-, and z-axes, respectively.

[0007] One embodiment of the present invention is a computer-readable storage medium on which the above program is recorded.

[0008] One embodiment of the present invention is a computer having the above program installed thereon. [Brief description of the drawings]

[0009] [Figure 1] 4 is a flow chart illustrating a method for estimating the volume of an object according to one embodiment of the present invention. [Figure 2A] FIG. 1 is a schematic perspective view illustrating a method for estimating the volume of an object according to one embodiment of the present invention. [Figure 2B] 1A-1C are schematic top views illustrating a method for estimating the volume of an object, according to one embodiment of the present invention. [Diagram 3] 1A-1C are schematic side views illustrating a method for estimating the volume of an object according to one embodiment of the present invention; [Figure 4] FIG. 2 is a schematic diagram illustrating a method for estimating the volume of an object according to one embodiment of the present invention. [Diagram 5] FIG. 2 is a schematic diagram illustrating a method for estimating the volume of an object according to one embodiment of the present invention. [Figure 6] FIG. 2 is a schematic diagram illustrating a method for estimating the volume of an object according to one embodiment of the present invention. [Figure 7A] FIG. 2 is a schematic diagram illustrating a method for estimating the volume of an object according to one embodiment of the present invention. [Figure 7B] FIG. 2 is a schematic diagram illustrating a method for estimating the volume of an object according to one embodiment of the present invention. [Figure 8A] FIG. 2 is a schematic diagram illustrating a method for estimating the volume of an object according to one embodiment of the present invention. [Figure 8B] FIG. 2 is a schematic diagram illustrating a method for estimating the volume of an object according to one embodiment of the present invention. [Figure 9] FIG. 2 is a schematic diagram illustrating a method for estimating the volume of an object according to one embodiment of the present invention. [Figure 10] FIG. 2 is a schematic diagram illustrating a method for estimating the volume of an object according to one embodiment of the present invention. [Figure 11] FIG. 2 is a schematic diagram illustrating a method for estimating the volume of an object according to one embodiment of the present invention. [Figure 12] FIG. 1 is a block diagram of a computer according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, each embodiment of the present invention will be described with reference to the drawings, etc. However, the present invention can be embodied in various forms without departing from the gist of the present invention, and should not be construed as being limited to the description of the embodiments exemplified below.

[0011] 1. How to estimate the volume of an object One embodiment of the present invention is a method for estimating the volume of an object. There are no restrictions on the objects to which the method can be applied, and the method can be applied to various objects having three-dimensional shapes. One example of an object is stones and boulders scattered on mountainsides and riverbanks, i.e., boulders. Depending on the location, it is often difficult for workers to approach and measure boulders, and surveying can be dangerous. However, as described in detail below, the method can efficiently estimate the volume by using images of the object acquired from three different directions. In addition, the method can estimate the volume by acquiring an image in which the entire boulder is exposed, and even if a part of the boulder is buried underground and the entire boulder is not exposed, the image of the object acquired from three different directions can be used to roughly estimate the volume of the object. In addition, the image of the object does not necessarily need to be acquired by a worker carrying an imaging device, and an unmanned vehicle or unmanned aerial vehicle equipped with an imaging device may be used. Therefore, the volume of the boulder can be quickly estimated while ensuring the safety of the worker. Hereinafter, the method will be described in detail using a boulder as an example of an object.

[0012] (1) Image acquisition FIG. 1 shows a flowchart of the method. In the method, first, as shown in FIG. 2A, images of the boulder are obtained from three different points using a three-dimensional camera. The three points may be appropriately set so that images of the boulder are obtained from three directions. More specifically, the three points may have the same or different vertical heights (altitudes). Similarly, the three points may have the same or different distances from the boulder. Also, as shown in FIG. 2B, which is a schematic diagram of a boulder viewed from above, if the first point is located in a first direction from the boulder (or the center of the boulder or a point on the boulder), the second point may be located in a second direction shifted from the first direction by an angle θ1 of 10° to 170°, 30° to 150°, or 45° to 135° in a horizontal plane. On the other hand, the third point may be in a third direction shifted by an angle θ2 of -10° to -170°, -30° to -150°, or -45° to -135° in the horizontal plane from the first direction. θ1 and θ2 may be the same or different. By acquiring images of the boulder from three points in this way, a first image (front image) acquired from the first point, a second image (left side image) acquired from the second point, and a third image (right side image) acquired from the third point are obtained. The number of images is not limited to three, and may be four or more. For example, in addition to the first to third images, a fourth image acquired from a point on the opposite side of the first point with respect to the boulder (for example, a point in a direction shifted by an angle of 135° to 225° in the horizontal plane from the first direction) may be used.

[0013] The imaging may be performed using an imaging device capable of acquiring an image including three-dimensional information as digital data. More specifically, imaging is performed using a three-dimensional camera. The three-dimensional camera may be a camera capable of acquiring a monochrome image or a camera capable of acquiring a color image. Each image is composed of a number of data points, each of which includes gray-scale information, arranged in a matrix of multiple rows and multiple columns. When the image is represented on a display, the data points correspond to pixels. When the image is a color image, each data point further includes color (red, green, or blue) information.

[0014] Here, the three-dimensional camera is a camera capable of acquiring not only the brightness data of the imaged object but also the distance to the imaged object. There is no restriction on the mechanism for acquiring the distance to the imaged object, and the three-dimensional camera may be a camera capable of acquiring the coordinate information of the imaged object, such as a stereo vision system, a time-of-flight (TOF) system, or a structured light system, or a combination of these systems. The stereo vision system is a system for measuring the distance to the imaged object using the difference in the position of the imaged object in images acquired by multiple cameras (stereo parallax). The TOF system is a system for measuring the distance to the imaged object by measuring the time it takes for light emitted from the three-dimensional camera to be reflected by the imaged object and return to the three-dimensional camera. The structured light system is a system for projecting a light pattern such as a stripe pattern onto the imaged object using a light source such as a laser or a light-emitting diode, and measuring the distance to the imaged object based on the distortion of the light pattern on the imaged object. By using a three-dimensional camera, an image can be constructed with data points each including gradation, color, and distance (depth) information.

[0015] Here, as shown in the schematic side view of Fig. 3, when acquiring the first to third images, it is preferable to simultaneously capture an image of the boulder, which is the subject of volume estimation, and a scale reference that serves as a reference for the scale. The scale reference may be a survey pole, or any object with a known size may be used. Alternatively, even if the size is not known, a common object that fits within all of the first to third images may be used as the scale reference. The common object may be, for example, a tree or vegetation that is present near the boulder, or another boulder.

[0016] (2) Scale adjustment As described above, the three points from which the images are acquired may differ in distance and altitude from the boulder. The angles θ1 and θ2 may also differ. This may result in different scales between the images. If the scales between the first image to the third image are different, the scales may be unified using a scale standard. In this way, the same length is represented by the same or substantially the same number of data points or pixels in all images, and the boulders can be represented at the same or substantially the same scale.

[0017] In addition, the rows and columns constituting the data points in each image are not necessarily horizontal or vertical, and if the imaging device is tilted when the image is captured, the rows and columns constituting the data points will deviate from the horizontal or vertical direction. If this deviation is significant, the tilt of the first to third images may be corrected, for example, by using a scale reference.

[0018] (3) Setting the occupied area Next, the area occupied by the boulder is trimmed in each image. The trimming is performed by setting an occupied area in each image. The occupied area is set as a rectangular area that occupies 80% to 120%, 85% to 115%, or 90% to 110% of the visible area of ​​the boulder. As shown in FIG. 3, the vertices of the occupied area may be located on the contour of the boulder, or may not overlap the contour. In addition, the vertices of the occupied area may or may not overlap the boulder in the image. Alternatively, the occupied area may be set so that its four sides inscribe or circumscribe the area occupied by the boulder. In this way, an occupied area that approximates the boulder can be obtained as two-dimensional information in each image. In addition, it is preferable that the occupied area is set so that a pair of opposing vertices do not overlap in the vertical or horizontal directions in each image.

[0019] A schematic diagram of the occupation areas set in the first to third images (hereinafter also referred to as the first occupation area, the second occupation area, and the third occupation area, respectively) is shown in FIG. 4. As shown in FIG. 4, the vertices of these occupation areas are expressed using independent coordinate systems that are independent between the images. The first occupation area is represented by the bottom left, bottom right, top right, and top left vertices V1 LL , V1 RL , V1 RU , V1 LU The second occupancy is defined by the bottom right, top right, top left, and bottom left vertices V2 RL , V2 RU , V2 LU , V2 LL The third occupancy is defined by the bottom-left, bottom-right, top-right, and top-left vertices V3. LL , V3 RL , V3 RU , V3 LU In this independent coordinate system, the horizontal axis may be set to be horizontal and the vertical axis to be vertical. Alternatively, when pixels or data points are arranged in a matrix, the arrangement direction of the matrix may be set to the horizontal axis or the vertical axis. The coordinates of the vertical axis and the horizontal axis are determined using the coordinates of the data points. As described above, each data point includes depth information. Therefore, each data point includes not only the vertical axis and the horizontal axis, but also coordinates on the axis in the depth direction perpendicular to these.

[0020] Next, preprocessing is performed on the first to third images, and the first to third occupancy areas are arranged on the local coordinates common to these images. Specifically, for the first image, vertex V1 LL The horizontal and vertical axes in the first image are set as the x-axis and z-axis of the local coordinate system, respectively. The depth axis is set as the y-axis of the local coordinate system. As a result, the vertex V1 LL , V1 RL , V1 RU , V1 LU The local coordinates of are (x1 (1) ,y1 (1) ,z1 (1) ), (x2 (1) ,y2 (1) ,z2 (1)), (x6 (1) ,y6 (1) ,z6 (1) ), (x5 (1) ,y5 (1) ,z5 (1) ) (Figure 5). Vertex V1 LL , V1 RL , V1 RU , V1 LU The local coordinates of are V1 LL Let (i.e., (x1 (1) ,y1 (1) ,z1 (1) )=(0,0,0), the number of data points or pixels that make up the first pixel, and the depth information.

[0021] On the other hand, in the second image, the horizontal and vertical axes are set to the y and z axes of the local coordinate system, respectively, and the depth axis is set to the x axis of the local coordinate system. RL is placed at the origin of the local coordinate system. Therefore, if θ1 is not 90°, the second image appears to rotate around the vertical axis. Therefore, the vertex V2 RL , V2 RU , V2 LU , V2 LL The local coordinates of are (x1 (2) ,y1 (2) ,z1 (2) ), (x5 (2) ,y5 (2) ,z5 (2) ), (x6 (2) ,y6 (2) ,z6 (2) ), (x4 (2) ,y4 (2) ,z4 (2) ) (Figure 5). Vertex V2 RL , V2 RU , V2 LU , V2 LL The local coordinates of are also set with the origin V2 RL Let (i.e., (x1 (2) ,y1 (2) ,z1 (2) )=(0,0,0)), the number of data points or pixels that make up the second pixel, and the depth information.

[0022] Similarly, in the third image, the horizontal and vertical axes are set to the y and z axes of the local coordinate system, respectively, and the depth axis is set to the x axis of the local coordinate system. LL is placed at the origin of the local coordinate system. Therefore, if θ2 is not -90°, the third image also appears to rotate around the vertical axis. Therefore, vertex V3 LL , V3 RL , V3 RU , V3 LU The local coordinates of are (x2 (3) ,y2 (3) ,z2 (3) ), (x3 (3) ,y3 (3) ,z3 (3) ), (x7 (3) ,y7 (3) ,z7 (3) ), (x6 (3) ,y6 (3) ,z6 (3) ) (Figure 5). Vertex V3 LL , V3 RL , V3 RU , V3 LU The local coordinates of are also set with the origin V3 LL Let (i.e., (x2 (3) ,y2 (3) ,z2 (3) )=(0,0,0)), the number of data points or pixels that make up the third pixel, and the depth information.

[0023] The above-mentioned occupied areas and the local coordinates of their vertices are summarized in Table 1 below. As described above, in each image, the occupied areas are preferably set so that a pair of opposing vertices do not overlap in the vertical or horizontal directions. Specifically, the first occupied area is preferably set so that the x-coordinates or z-coordinates of the opposing vertices do not match. The second occupied area and the third occupied area are preferably set so that the y-coordinates or z-coordinates of the opposing vertices do not match. By setting the occupied areas in this manner, the bottom left, bottom right, top right, and top left vertices of each occupied area are uniquely determined. [Table 1]

[0024] (4) Construction of an approximate hexahedron Next, the occupancy areas set in each image are merged to construct an approximate hexahedron that approximates the boulder (Fig. 6). As shown in Fig. 6, this approximate hexahedron is placed in an XYZ global coordinate system consisting of mutually orthogonal X-, Y-, and Z-axes that are independent of the local coordinate system, and is defined by eight vertices. However, the information on the shape of the boulder obtained from the first, second, and third images does not include all shape information of the boulder, and the shape information of the boulder in the blind spots from the first, second, and third points is missing. Therefore, the approximate hexahedron is constructed under several assumptions described below. In the following, the vertices of the approximate hexahedron are called nodes to distinguish them from the vertices of the first to third occupancy areas. Therefore, the approximate hexahedron is defined by nodes N1 to N8. Coordinates in the local coordinate system are expressed using lowercase x, y, and z, and coordinates in the global coordinate system are expressed using uppercase X, Y, and Z.

[0025] A. Merging of the first and second occupied regions First, the first occupancy area is used as a reference plane in the global coordinate system, and the second occupancy area is merged into the first occupancy area. In other words, the first occupancy area is placed in the global coordinate system so that the x-axis, y-axis, and z-axis of the local coordinate system where the first occupancy area is placed are parallel to the x-axis, y-axis, and z-axis of the global coordinate system, respectively. At this time, vertex V1 LL and vertex V2 RL It is assumed that the origin (0,0,0) of the global coordinate system is constituted by (Assumption 1). Based on this Assumption 1, node N1 is set to the origin (X,Y,Z=(0,0,0)) in the global coordinate system. In constructing the approximate hexahedron, the origin of the global coordinate system does not have to be node N1, and other nodes (nodes N2, N5, or N6, etc.) may be set as the origin of the global coordinate system to fuse the respective occupancy areas. In the following explanation, the first occupancy area and the second occupancy area are fused first, and then the first occupancy area and the third occupancy area are fused, but it is also possible to fuse the first occupancy area and the third occupancy area first, and then fuse the first occupancy area and the second occupancy area.

[0026] Since the first occupied area is used as the reference surface in the global coordinate system, by assumption 1, the node N1 is set and the vertex V1 is set. RL constitutes node N2, whose global coordinates are (X,Y,Z)=(x1 (2) ,y1 (2) ,z1 (2) ) The Y-axis and the y-axis are parallel, and the vertex V2 that gives the nodes N4 and N8 is LL and V2 LU Since the local coordinates of N4 and N8 are obtained only from the second image, the global coordinates of the vertices V2 of the second occupied area are LL and vertex V2 LU Therefore, the global coordinates of node N4 and node N8 are (X,Y,Z) = (x4 (2) ,y4 (2) ,z4 (2) ), (x8 (2) ,y8 (2) ,z8 (2) )

[0027] Next, vertex V1 LU and vertex V2 RU Set node N5 using these vertices V1 LU , V2 RU The local coordinates of can be obtained from the first and second images, respectively, but under the above assumption 1, they do not necessarily match in global coordinates (Fig. 7A). This is because the altitudes of the points where the first and second images are obtained may differ, and the vertex V1 selected in setting the occupied area may differ. LU and vertex V2 RU This is because the coordinates of node N5 may not necessarily be the same as those of vertex V1, and there may be errors in the scale adjustment. LU and V2 RU Assume that the global coordinates of node N1 are (X,Y,Z) = ((x5 (1) +x5 (2) ) / 2,(y5 (1) +y5 (2) ) / 2,(z5 (1) +z5 (2)) / 2), and node N5 is set (FIG. 7B).

[0028] B. Merging of the first and third occupancy domains Next, the first and third occupancy regions are merged (Fig. 6). Specifically, similar to the merging of the first and second occupancy regions, the bottom left vertex V3 of the third occupancy region is merged. LL is the bottom right vertex V1 of the first occupied region. RL Assumption 3: As mentioned above, vertex V3 LL and vertex V1 RL The global coordinates of node 2 formed by the above are the lower right vertex V2 of the first occupied area used as the reference surface. RL The local coordinates of are adopted.

[0029] Next, a node N6 is placed in the global coordinate system. Specifically, the node N6 is placed at the top right vertex V1 of the first occupied area. RU and the top-left vertex V3 of the third occupied region LU The node N6 is set in the global coordinate system by fusing the above. As with the setting of the node N5, the altitudes of the points where the first and third images are acquired may differ, and the vertex V1 selected in the setting of the occupied area may be different. RL and vertex V3 LL Because vertex V1 may not necessarily be the same location, and there may be errors in the scale adjustment, RU and vertex V3 LU do not necessarily coincide in global coordinates (Fig. 8A). Therefore, the global coordinates of node N6 are the same as those of vertex V1. RU Local coordinates of (x6 (1) ,y6 (1) ,z6 (1) ) and vertex V3 LU Local coordinates of (x6 (3) ,y6 (3) ,z6 (3) ) (Assumption 4). However, the vertex V3 with the origin (x,y,z)=(0,0,0) in the local coordinates of the third occupied region LL is not the origin (X,Y,Z)=(0,0,0) in global coordinates. That is, in the fusion of the first and third occupancy areas, vertex V3 LLis vertex V1 RL The vertex V3 is shifted from the origin of the global coordinate system by the local coordinates of LU The local coordinates of vertex V3 LU Local coordinates of (x6 (3) ,y6 (3) ,z6 (3) ) to vertex V1 RL The local coordinates of (x2 (1) ,y2 (1) ,z2 (1) ) to obtain the global coordinates of node N6. Therefore, vertex V1 RU and vertex V3 LU The average value of the local coordinates of (X,Y,Z)={x6 (1) +(x6 (3) +x2 (1) )} / 2,{y6 (1) +(y6 (3) +y2 (1) )} / 2,{z6 (1) +(z6 (3) +z2 (1) )} / 2} is adopted as the global coordinate of node N6 (Figure 8B).

[0030] Vertex V3, which gives node N7, one of the remaining two nodes of the approximate hexahedron RU is obtained only from the third image, so this vertex V3 RU The local coordinates of node N7 are adopted as the global coordinates of node N7. However, the origin of the local coordinates of the third occupied region (i.e., vertex V3 LL ) is not the origin of the global coordinate system, so the third occupied area vertex V3 is set in the same way as the node N6. RU Local coordinates of (x7 (3) ,y7 (3) ,z7 (3) ) to vertex V1 RL The local coordinates of (x2 (1) ,y2 (1) ,z2 (1) ) is added. Therefore, the global coordinates of node N7 are (X,Y,Z) = (x7 (3) +x2 (1) ,y7 (3) +y2 (1) ,z7 (3) +z2 (1) )

[0031] Similar to the definition of node N7, vertex V3 gives the remaining node N3. RL is obtained only from the third image, so this vertex V3 RL The local coordinates of node N7 are adopted as the global coordinates of node N7. However, the origin of the local coordinates of the third occupied region (i.e., vertex V3 LL ) is not the origin of the global coordinate system, so the third occupied area vertex V3 is set in the same way as the node N6. RL The local coordinates of (x3 (3) ,y3 (3) ,z3 (3) ) to vertex V1 RL The local coordinates of (x2 (1) ,y2 (1) ,z2 (1) ) is added. Therefore, the global coordinates of node N3 are (X,Y,Z) = (x3 (3) +x2 (1) ,y3 (3) +y2 (1) ,z3 (3) +z2 (1) )

[0032] By performing the above operations, an approximate hexahedron is constructed in the XYZ global coordinate system (Figure 6). The XYZ coordinates of nodes N1 to N8 are summarized in Table 2. [Table 2]

[0033] (5) Calculating the volume of an approximate hexahedron The volume of the approximate hexahedron obtained can be calculated by dividing the approximate hexahedron into six quadrangular pyramids with an arbitrary internal point Pc as a vertex, and then calculating the sum of the volumes of all the quadrangular pyramids. The internal point Pc is defined as follows:

number

[0034] For example, the volume V of a square pyramid (see FIG. 9) having the surface formed by nodes N1, N4, N5, and N8 as its base and point Pc as its apex is expressed by the following formula.

number

[0035] In this method, the shape of the occupied area set in each image is not necessarily limited to a rectangle. For example, as shown in FIG. 10, in each of the first image, the second image, and the third image, in addition to the lower left, lower right, upper right, and upper left vertices, vertex V1 T , V2 T , V3 T Alternatively, although not shown, an occupied area having a polygonal shape with hexagons or more may be formed. Note that it is preferable that the number of vertices of the occupied areas is the same among the first image, the second image, and the third image.

[0036] When setting a pentagonal occupied area, the approximate polyhedron is an approximate nonahedron defined by nodes N1 to N9 (see Figure 11). The global coordinates of node N9 are the vertex V1 of the first occupied area. T The local coordinates of the first occupancy area vertex V1 T and the vertex V2 of the second occupied region T The average of the local coordinates of (X,Y,Z)=((x T (1) +x T (2) ) / 2,(y T (1) +y T (2) ) / 2,(z T (1) +z T (2) ) / 2)) or the third occupancy vertex V3 T In this case, when the first occupancy area and the third occupancy area are merged, the vertex V3 of the third occupancy area is T The local coordinates of the first occupancy vertex V1 RLTo shift the local coordinates of node N9, the global coordinates of node N9 are (X,Y,Z)=({x T (1) +x T (2) +(xT (3) +x2 (1) )} / 3,{y T (1) +y T (2) +(yT (3) +y2 (1) )} / 3,{z T (1) +z T (2) +(zT (3) +z2 (1) )}) / 3.

[0037] The method for calculating the volume of an approximate nine-sided polygon can be arbitrary. For example, the volume of the hexahedron defined by nodes N1 to N8 is calculated using the method described above. The volume of the tetrahedron defined by nodes N5 to N9 can be calculated by dividing it into four triangular pyramids with the internal point P´c as a vertex, and then calculating the volume as the sum of the volumes of all the triangular pyramids. The sum of the volumes of these hexahedrons and tetrahedrons is the volume of the approximate nine-sided polygon.

[0038] 2. Program, computer-readable storage medium, and computer Another embodiment of the present invention is a program for estimating the volume of an object (volume estimation program) as described above. The volume estimation program may include not only machine code such as that generated by a compiler, but also high-level language code executed by a server using an interpreter or the like.

[0039] A computer-readable recording medium on which the volume estimation program is recorded is also one of the embodiments of the present invention. Examples of the computer-readable recording medium include magnetic media such as hard disks, flexible disks, and magnetic tapes, optical media such as CD-ROMs and DVDs, magneto-optical media such as floptical disks, and hardware devices configured to store and execute the volume estimation program, such as ROMs, RAMs, and flash memories.

[0040] Another embodiment of the present invention is a computer having the volume estimation program installed therein. The computer is a device having a communication function and a calculation function, and may be a notebook or stationary information processing device, or may be a mobile communication terminal such as a tablet computer.

[0041] As shown in the block diagram of FIG. 12, the computer 100 is provided with a control unit 102 that controls the operation of the computer 100, as well as an input unit 104, an output unit 106, a transmission / reception unit 108, a storage unit 110, an audio output unit 112, an input port 114, and the like, all of which are controlled by the control unit 102. The storage unit 110 stores a volume estimation program and the like, together with a basic application program for operating the computer 100. The control unit 102 includes a processor such as a central processing unit (CPU), and controls various processes executed by the computer 100 by operating the basic application program and the volume estimation program stored in the storage unit 110. This makes it possible to perform volume estimation of an object according to the present method. The input unit 104 is a user interface used to input commands and information to the computer 100, and typically includes a keyboard, a touch panel, a mouse, or a combination of these. The output unit 106 provides various data stored in the storage unit 110 as images or printed matter, and is an output device such as a display device, such as a liquid crystal display device or an organic electroluminescence display device, or a printer. When a touch panel is used as the input unit 104, the touch panel may be disposed on the display device. The transmitting / receiving unit 108 has a function of communicating with an external device such as an imaging device via a network. The audio output unit 112 is a speaker having a function of generating various sounds. The input port 114 is a wired interface that can be physically connected to a storage medium such as a memory card, and this makes it possible to connect the storage medium in which images are stored in the imaging device to the computer 100.

[0042] The volume estimation program is installed from a computer readable medium into the storage unit 110. Alternatively, the volume estimation program may be downloaded into the storage unit 110 from a network.

[0043] The above-mentioned method allows the volume of boulders to be estimated from images of boulders taken from three or more locations. This method does not allow the exact volume of the boulders or the volume of the part buried in the ground to be obtained. However, in general civil engineering construction management, the exact volume of the boulders is not required, and according to the manual, the volume of the part of the boulders exposed above the ground (provisional volume) is calculated, and then the dimensions of the height, length, and width of the side and cross-sectional shape that are assumed to be approximately the average cross-sectional shape for each exposure order are measured to calculate the actual volume. Therefore, this method can be said to be a simple method for determining the provisional volume of boulders. In addition, this method allows the volume of boulders to be estimated in an extremely short time by simply using images taken from three locations without using general surveying equipment. Therefore, the volume of a large amount of boulders (provisional volume) can be estimated in a short time without placing a heavy burden on workers and without exposing them to the dangers associated with field surveying.

[0044] The above-described embodiments of the present invention may be combined as appropriate as long as they are not mutually inconsistent. Any embodiment in which a person skilled in the art appropriately adds or deletes components or modifies the design based on each embodiment is also included in the scope of the present invention as long as it includes the gist of the present invention.

[0045] Even if there are other effects and advantages different from those brought about by the respective embodiments described above, those which are clear from the description in this specification or which can be easily predicted by a person skilled in the art are naturally understood to be brought about by the present invention. [Explanation of symbols]

[0046] 100: computer, 102: control unit, 104: input unit, 106: output unit, 108: transmission / reception unit, 110: storage unit, 112: audio output unit, 114: input port

Claims

1. providing, using a three-dimensional camera, a first image of an object taken from a first location, a second image of the object taken from a second location, and a third image of the object taken from a third location; setting a first rectangular occupancy area, a second rectangular occupancy area, and a third rectangular occupancy area occupying 80% to 120% of an area of ​​the object in the first image, the second image, and the third image, respectively; determining, in the first image, the second image, and the third image, x-coordinates, y-coordinates, and z-coordinates of each vertex of the first occupation area, the second occupation area, and the third occupation area, respectively, on a local coordinate system common to the first image, the second image, and the third image; constructing a hexahedron approximating the object based on local coordinates of the first occupation region, the second occupation region, and the third occupation region in an XYZ global coordinate system independent of the x-coordinate, the y-coordinate, and the z-coordinate; and calculating the volume of the hexahedron; A method for estimating the volume of an object, wherein the X-axis, Y-axis, and Z-axis of the XYZ global coordinate system are parallel to the x-coordinate axis, the y-coordinate axis, and the z-coordinate axis, respectively.

2. each of the first image, the second image, and the third image is acquired to include the object and a scale reference; The method of claim 1 , further comprising: unifying the scales of the first image, the second image, and the third image using the scale reference.

3. the first point is located in a first direction relative to the object; the second point is located in a second direction between 20° and 170° relative to the first direction; The method of claim 1 , wherein the third point is located in a third direction between −20° and −170° relative to the first direction.

4. the first occupation area is set such that the x-coordinates or the z-coordinates of the vertices of the first occupation area facing each other are different from each other; the second occupation area is set such that the y coordinates or the z coordinates of the opposing vertices of the second occupation area are different from each other; The method according to claim 1 , wherein the third occupancy area is set such that the y coordinates or the z coordinates of opposing vertices of the third occupancy area are different from each other.

5. The processing device includes: determining, on a local coordinate system common to the first image, the second image, and the third image, the x-coordinate, the y-coordinate, and the z-coordinate of each vertex of a first occupancy area, a second occupancy area, and a third occupancy area of ​​a rectangle occupying 80% or more and 120% or less of a set area of ​​the object in a first image, a second image, and a third image of the object acquired by using a three-dimensional camera at a first point, a second point, and a third point, respectively; constructing a hexahedron approximating the object based on local coordinates of the first occupation region, the second occupation region, and the third occupation region in an XYZ global coordinate system independent of the x-coordinate, the y-coordinate, and the z-coordinate; and configured to cause the program to calculate the volume of the hexahedron; A program for estimating the volume of an object, wherein the X-axis, Y-axis, and Z-axis of the XYZ global coordinate system are parallel to the x-coordinate axis, the y-coordinate axis, and the z-coordinate axis, respectively.

6. each of the first image, the second image, and the third image includes the object and a scale reference; The computer-readable medium according to claim 5 , further configured to cause the processor to unify the scales of the first image, the second image, and the third image using the scale reference.

7. A computer-readable storage medium on which the program according to claim 5 is recorded.

8. A computer having the program according to claim 5 installed thereon.

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