JP5423491B2 - Reference position calculation system and reference position calculation method - Google Patents

Description

  The present invention relates to a reference position calculation system and a reference position calculation method used for measuring a position or moving speed of an imaging target based on a thermal image captured by an imaging unit.

  There are methods for detecting the presence of an imaging target and measuring the position and moving speed of the imaging target based on an image captured by a camera.

  In Patent Document 1, in order to prevent the influence due to the presence or absence of illumination, a vehicle, a pedestrian, or the like on a night road is detected based on an image captured by an infrared camera, or the position of the detected vehicle, a pedestrian, or the like is detected. And a device for measuring the moving speed is described.

  In order to measure the position and moving speed of an imaging target such as a vehicle or a pedestrian with high accuracy with the apparatus described in Patent Document 1, the coordinate values in the image coordinate system of the imaging target in the image output from the infrared camera And the measured coordinate values need to be converted into coordinate values in the world coordinate system.

  Non-Patent Document 1 and Non-Patent Document 2 describe a method of converting a coordinate value in an image coordinate system into a coordinate value in a world coordinate system.

  In the methods described in Non-Patent Document 1 and Non-Patent Document 2, a model such as a perspective projection or a Tsai camera model is set, and coordinate values in the image coordinate system are converted into coordinate values in the world coordinate system.

  In the methods described in Non-Patent Document 1 and Non-Patent Document 2, in order to set a model, a plurality of corresponding points where the coordinate values in the image coordinate system and the coordinate values in the world coordinate system are known positions are set in advance. It is necessary to prepare.

  In order to prepare corresponding points, a marker such as a light source is set at a position where the coordinate value in the world coordinate system is known, and the coordinate value of the image coordinate system of the marker in the image captured by the camera is measured. Thus, the coordinate value in the world coordinate system of the marker is associated with the coordinate value in the image coordinate system. When the camera is a far infrared camera, a heat source is generally used for the marker.

  When measuring the position of an object moving on a road in a road monitoring system or the like, generally, a correspondence table for associating the coordinate values of the image coordinate system with the coordinate values of the world coordinate system is prepared in advance. In order to associate each coordinate value with the correspondence table, methods described in Non-Patent Document 1 and Non-Patent Document 2 are used. Further, a road surface is created on the world coordinate system by linearly interpolating between corresponding points, and the created road surface on the world coordinate system is associated with the road surface on the image coordinate system. Then, based on the image which imaged the object which moves on a road surface, it becomes possible to measure the position or moving speed of an object. Therefore, in order to accurately associate the road surface on the world coordinate system with the road surface on the image coordinate system, it is required to accurately associate the coordinate values of the image coordinate system with the coordinate values of the world coordinate system.

  Patent Document 2 describes a method of calculating an image coordinate value of an imaging target based on an outline of the imaging target in an image captured by a camera, and calculating a coordinate value of a world coordinate system corresponding to the calculated image coordinate value. ing.

JP 2000-348282 (paragraphs 0010 to 0019, FIG. 1) Japanese Patent Laid-Open No. 2001-264037 (paragraphs 0022 to 0115, FIG. 1)

Xugang, Saburo Tsuji, “Three-dimensional Vision”, first edition, Japan, Kyoritsu Publishing Co., Ltd., April 20, 1998, p. 79-82 Roger Y. Tsai, “A Versatile Camera Calibration Technique for High Accuracy 3D Machine Vision Metrology Using Off the Shelf Tbe Cameras and Lensis” Metrology Using Off-the-Shelf TV Cameras and Lenses ", (USA), IJ Journal of Robotics and Automation, Vol. RA3, No. 4, August 1987, p. 323-344

  In an image in which a heat source as a marker is imaged by a far-infrared camera, the heat source is imaged across a plurality of pixels, or the heat generated by the heat source is conducted to surrounding objects, so that the outline of the heat source is For example, the coordinates of the heat source in the image coordinate system cannot be set to the coordinate value of one pixel with high accuracy.

  Therefore, in the apparatus described in Patent Document 1, the coordinate value in the image coordinate system cannot be accurately associated with the coordinate value in the world coordinate system by using the heat source, and the road coordinate system or the like is on the world coordinate system. The road surface to be created cannot be accurately associated with the road surface on the image coordinate system.

  Therefore, in the apparatus described in Patent Document 1, since the coordinate value in the image coordinate system is not accurately associated with the coordinate value in the world coordinate system, the image coordinate system measured before and after moving the imaging target The position and moving speed of the imaging target cannot be measured with high accuracy based on the coordinate values before and after the movement of the imaging target in the world coordinate system calculated according to the coordinate value of the imaging target.

  Therefore, the present invention provides a reference position calculation system and a reference position calculation method capable of calculating with high accuracy the coordinate value in the image coordinate system of the position used as a reference in the thermal image captured by the imaging device. Objective.

  The reference position calculation system according to the present invention is a reference position calculation system used for measuring the position or moving speed of an imaging target based on a thermal image, and a reflecting member that reflects far infrared rays and a far infrared ray that is radiated by a reflecting member. An apparatus for position measurement including a heat source installed at a position to be reflected, an imaging apparatus for outputting a thermal image obtained by imaging a position measurement apparatus installed at a position corresponding to a position at which an imaging target is imaged, and an imaging apparatus An image processing device including a coordinate value calculating unit that calculates a coordinate value of a position measuring device in an image coordinate system of the thermal image based on the thermal image output by the coordinate value calculating unit of the image processing device, In the thermal image output by the imaging device, calculating the coordinate value in the image coordinate system of the pixel at the center of the region where the intensity of the far infrared ray per unit area is a predetermined value or more And butterflies.

  A reference position calculation method according to the present invention is a reference position calculation method for calculating coordinates of a reference position used for measurement of a position of an imaging object or a moving speed based on a thermal image, a reflecting member that reflects far infrared rays, and a radiation In a thermal image in which a position measuring device installed at a position corresponding to a position where an imaging target is imaged includes a heat source installed at a position where the far infrared rays reflected by the reflecting member are captured by the imaging device, a unit In order to change the area of the region where the intensity of far-infrared rays per area is equal to or greater than a predetermined value, the angle of the support member supporting the reflecting member with respect to the horizontal plane and the angle with respect to the predetermined direction in the horizontal plane is changed to support the reflecting member At the timing when the angle of the member with respect to the horizontal plane or the angle with respect to a predetermined direction in the horizontal plane is changed, the imaging apparatus is instructed to perform imaging In the thermal image output by the imaging device, area information indicating the area of the region is generated, and among the thermal images output by the imaging device, in the thermal image having the widest area indicated by the generated area information, per unit area The coordinate value in the image coordinate system of the pixel at the center of the region where the intensity of the far infrared ray is greater than or equal to a predetermined value is calculated.

  ADVANTAGE OF THE INVENTION According to this invention, the coordinate value in the image coordinate system of the position used for a reference | standard in the thermal image imaged with the imaging device can be calculated with high precision.

It is explanatory drawing which shows the structural example of the reference | standard position calculation system of embodiment of this invention. It is explanatory drawing which shows the structural example of a marker. It is explanatory drawing which shows the change of the pan angle of a supporting member. It is explanatory drawing which shows the change of the tilt angle of a supporting member. It is explanatory drawing which shows the example of the thermal image which the imaging device output. It is a flowchart which shows operation | movement of the reference | standard position calculation system of embodiment of this invention. It is explanatory drawing which shows the example of the image which the imaging device imaged. It is explanatory drawing which shows a response | compatibility with the coordinate value of an image coordinate system, and the coordinate value of a world coordinate system. It is a block diagram which shows the outline | summary of this invention.

  An embodiment of a reference position calculation system according to the present invention will be described with reference to the drawings. FIG. 1 is an explanatory diagram illustrating a configuration example of a reference position calculation system according to an embodiment of this invention.

  As illustrated in FIG. 1, the reference position calculation system according to the embodiment of the present invention controls an imaging device 20 that outputs a captured thermal image, a marker 10 that is imaged by the imaging device 20, and the imaging device 20 and the marker 10. An image processing apparatus 30 is included.

  The imaging device 20 is installed in a place where an imaging target can be imaged. Specifically, the imaging device 20 is installed, for example, in a place where a road on which a car that is an imaging target travels can be imaged. And the marker 10 is installed in the place according to the position used for a reference | standard in the thermal image imaged with the imaging device 20. FIG. Specifically, for example, the marker 10 creates a road surface corresponding to a road through which a car imaged by the imaging device 20 passes on a world coordinate system by linear interpolation and associates it with an image coordinate system. It is installed at a location corresponding to the position where the coordinate value in the coordinate system and the coordinate value in the image coordinate system are associated with each other.

  FIG. 2 is an explanatory diagram illustrating a configuration example of the marker 10. As shown in FIG. 2, the marker 10 fixes a heat source 12 that emits far-infrared rays radially, that is, concentric spheres, a reflector 11 that has an inner wall formed into a parabolic concave shape, and a heat source 12. The fixing member 13, the support member 15 that supports the reflecting plate 11, and the angles of the support member 15 (an angle with respect to a predetermined direction in a horizontal plane (referred to as a pan angle) and an angle with respect to a horizontal plane in a vertical plane (referred to as a tilt angle)) are controlled. The drive part 14 is included.

  The fixing member 13 fixes the heat source 12 that emits far-infrared rays radially to the focal point of the reflector 11 formed in a parabolic shape. Specifically, the fixing member 13 fixes, for example, the center of the heat source 12 to the focal point of the reflection plate 11.

  The reflector 11 is, for example, a mirror that reflects far-infrared rays with an inner wall formed in a parabolic shape. Moreover, the reflecting plate 11 in this embodiment is shape | molded so that the focus of the inner wall of the concave shaped reflecting plate 11 shape | molded by the parabolic shape may be located inside the opening surface formed by concave shape. Therefore, the inner wall of the reflecting plate 11 reflects far-infrared rays emitted by the heat source 12 fixed at the focal point in a certain direction. Therefore, the outline of the reflecting plate 11 can be clarified in the far-infrared thermal image emitted by the heat source 12 imaged by the imaging device 20.

  Moreover, the reflecting plate 11 in this embodiment is shape | molded so that the direction of the opening surface of the reflecting plate 11 may be parallel to the symmetrical axis line of the inner wall of the reflecting plate 11 shape | molded in the paraboloid shape. Therefore, the shape of the opening surface of the reflecting plate 11 in this embodiment is circular.

  Therefore, when the support member 15 is controlled by the drive unit 14 and the position of the imaging device 20 is a front position of the reflecting plate 11 (a position facing the opening surface of the reflecting plate 11), an image is taken by the imaging device 20. In the thermal image, far infrared rays emitted by the heat source 12 and reflected by the inner wall of the reflecting plate 11 are imaged in a circle. Then, compared with the case where the position of the imaging device 20 is a position other than the front surface of the reflecting plate 11, the region of the far infrared ray reflected by the inner wall of the reflecting plate 11 (that is, the region of the opening surface in the thermal image) is captured. Wide area.

  The drive unit 14 controls the pan angle and tilt angle of the support member 15 in accordance with instructions from the image processing device 30. FIG. 3 is an explanatory diagram showing changes in the pan angle of the support member 15. As illustrated in FIG. 3, the drive unit 14 controls the support member 15 in a range of 0 ° ≦ pan angle <360 ° in accordance with an instruction from the image processing apparatus 30.

  FIG. 4 is an explanatory diagram showing changes in the tilt angle of the support member 15. As illustrated in FIG. 4, the drive unit 14 controls the support member 15 in a range of 0 ° ≦ tilt angle <180 ° in accordance with an instruction from the image processing device 30. Note that when the tilt angle is 0 °, the front surface of the reflecting plate 11 is oriented in the horizontal direction.

  The heat source 12 becomes a temperature higher than the temperature around the marker 10 and emits far infrared rays in a radial pattern. The heat source 12 is, for example, an electric heater.

  The imaging device 20 is a device having a function of imaging and outputting a thermal image, and is, for example, a far infrared camera. The imaging device 20 outputs a thermal image to the image processing device 30. FIG. 5 is an explanatory diagram illustrating an example of a thermal image output by the imaging device 20. In FIG. 5, the region of the inner wall of the reflector 11 that reflects far infrared rays emitted by the heat source 12 of the marker 10 is shown by white pixels. That is, in the example shown in FIG. 5, the opening surface of the reflecting plate 11 is shown by white pixels.

  The image processing device 30 includes a coordinate value calculation unit 31, an angle instruction unit 32, an imaging instruction unit 33, and an area information generation unit 34. The coordinate value calculation means 31 calculates the center coordinate value of a region where the intensity of far infrared rays per unit area is equal to or greater than a predetermined value in the thermal image output from the imaging device 20.

  The angle instruction unit 32 instructs the drive unit 14 of the marker 10 about the pan angle and the tilt angle of the support member 15. The imaging instruction unit 33 instructs the imaging device 20 to perform imaging at the timing when the driving unit 14 of the marker 10 changes the pan angle or the tilt angle of the support member 15 in accordance with an instruction from the angle instruction unit 32. The area information generation unit 34 calculates the area of a region where the intensity of far infrared rays per unit area is equal to or greater than a predetermined value in the thermal image output from the imaging device 20. Specifically, the image processing apparatus 30 counts the number of pixels (the number of white pixels in the example shown in FIG. 5) constituting the region where the intensity of far infrared rays per unit area is equal to or greater than a predetermined value.

  The operation of the system shown in FIG. 1 will be described with reference to the drawings. FIG. 6 is a flowchart showing the operation of the reference position calculation system according to the embodiment of the present invention.

  The angle instruction means 32 of the image processing apparatus 30 instructs the drive unit 14 of the marker 10 to set the pan angle and tilt angle to 0 °. The drive unit 14 controls the angle of the support member 15 so that the pan angle and the tilt angle become 0 ° (step S101).

  Then, the image processing apparatus 30 performs an initialization process (step S102). Specifically, the image processing apparatus 30 resets a pan angle control end flag “FLG”, which is a flag indicating whether or not the pan angle control is ended. In the present embodiment, the image processing apparatus 30 sets 0 to the value of the pan angle control end flag “FLG”. Further, the image processing apparatus 30 sets 0 to the value of the variable “MAX” indicating the maximum value of the number of white pixels. The image processing apparatus 30 sets 0 to the value of the variable “pan” indicating the pan angle, and sets 0 to the value of the variable “tilt” indicating the tilt angle.

  Further, the image processing apparatus 30 sets a variable “ANG_P” indicating the pan angle when the number of white pixels reaches the maximum value and a variable “ANG” indicating the tilt angle when the number of white pixels reaches the maximum value. ANG_T ”is set to 0 respectively.

  When the thermal image in which the marker 10 is captured by the imaging device 20 is output, and the image processing device 30 receives the thermal image output by the imaging device 20 (step S103), the image processing device 30 generates a heat source for the marker 10. The binarized image data is generated so that the area emitted by 12 and the far infrared rays reflected by the reflecting plate 11 is represented by white pixels, and the other area is represented by black pixels (step S104). Specifically, for example, an image that is binarized so that a region where the intensity of far-infrared rays per predetermined unit area is equal to or greater than a predetermined value is expressed by white pixels, and the other region is expressed by black pixels. Generate data.

  The area information generation unit 34 of the image processing device 30 calculates the area of the region formed by the white pixels based on the image data binarized by the process of step S104 (step S105). Specifically, the image processing device 30 counts the number of white pixels. Hereinafter, the variable indicating the area value (specifically, the number of white pixels) calculated in the process of step S105 is “M”.

  When the image processing apparatus 30 determines that the pan angle control has not ended (Y in step S106), the image processing apparatus 30 proceeds to the process in step S107 and determines that the pan angle control has ended (step S106). N), the process proceeds to step S113.

  Specifically, when the value of the pan angle control end flag “FLG” is 0 in the process of step S106, the image processing apparatus 30 determines that the pan angle control has not ended, and the pan angle control is performed. If the value of the end flag “FLG” is not 0, it is determined that the control of the pan angle has ended.

  When the value of the variable “M” is larger than the value of the variable “MAX” indicating the maximum number of white pixels (Y in step S107), the image processing apparatus 30 sets the value of the variable “M” to the variable “MAX. The value of the variable “pan” indicating the angle of the pan angle is set to the value of the variable “ANG_P” indicating the pan angle when the number of white pixels reaches the maximum value. Then, the coordinate value calculation unit 31 of the image processing device 30 calculates the center coordinate value of the white pixel on the X axis of the image coordinate system (step S108).

  FIG. 7 is an explanatory diagram illustrating an example of an image captured by the imaging device 20. In the example shown in FIG. 7, in the image coordinate system, the maximum value of the coordinate value on the X axis of the region by the white pixel (the region shown by an ellipse in FIG. 7) is x2, and the minimum value is x1. ing. That is, in the image coordinate system, the coordinate values at both ends on the X axis of the region by the white pixel are x1 and x2. The coordinate value calculation means 31 of the image processing apparatus 30 calculates (x2−x1) / 2 to calculate the X-axis center coordinate value xc of the white pixel in the image coordinate system.

  When the value of the variable “M” is equal to or less than the value of the variable “MAX” indicating the maximum number of white pixels (N in Step S107), or after the processing in Step S108, the image processing apparatus 30 It is determined whether or not the value of the variable “pan” indicating is less than 360 (step S109).

  When the value of the variable “pan” indicating the angle of the pan angle is less than 360 (N in step S109), the image processing apparatus 30 adds 0.1 to the value of the variable “pan” indicating the angle of the pan angle. (Step S110). The angle instruction unit 32 of the image processing device 30 transmits an instruction to control the angle of the support member 15 to the angle indicated by the value of the variable “pan” set in the process of step S110 to the drive unit 14 of the marker 10. . Then, the imaging instruction unit 33 of the image processing device 30 instructs the imaging device 20 to capture a thermal image.

  In addition, when the value of the variable “pan” indicating the angle of the pan angle is not less than 360 (Y in step S109), the image processing apparatus 30 sets the variable indicating the pan angle when the number of white pixels reaches the maximum value. The value of “ANG_P” is set to the value of the variable “pan” indicating the angle of the pan angle, and 1 is set to the value of the pan angle control end flag “FLG” (step S111).

  The angle instruction means 32 of the image processing apparatus 30 sends the value of the variable “pan” set in the process of step S111 to the driving unit 14 of the marker 10 (that is, the pan angle when the number of white pixels reaches the maximum value). An instruction to control the angle of the support member 15 is transmitted to the angle indicated by the variable “ANG_P” indicating “ The drive unit 14 of the marker 10 controls the support member 15 to a pan angle according to an instruction from the image processing device 30 (step S112). Further, the imaging instruction unit 33 of the image processing apparatus 30 instructs the imaging apparatus 20 to capture a thermal image, and the process proceeds to step S103.

  When the image processing device 30 determines that the control of the pan angle is finished (N in step S106), the image processing device 30 sets the variable “MAX” in which the value of the variable “M” indicates the maximum number of white pixels. Is greater than the value of “” (Y in step S113), the variable “M” is set to the value of the variable “MAX”, and the variable “indicating the tilt angle when the number of white pixels reaches the maximum value” The value of the variable “tilt” indicating the tilt angle is set to the value of “ANG_T”. Then, the coordinate value calculation unit 31 of the image processing device 30 calculates the center coordinate value of the white pixel on the Y axis of the image coordinate system (step S114).

  In the example shown in FIG. 7, in the image coordinate system, it is indicated that the maximum value of the coordinate value on the Y axis of the region by the white pixel is y2, and the minimum value is y1. That is, in the image coordinate system, the coordinate values at both ends on the Y axis of the region formed by white pixels are y1 and y2. The coordinate value calculation means 31 of the image processing apparatus 30 calculates (y2−y1) / 2 to calculate the Y-axis center coordinate value yc of the white pixel in the image coordinate system.

  When the value of the variable “M” is equal to or less than the value of the variable “MAX” indicating the maximum number of white pixels (N in Step S113), or after the processing in Step S114, the image processing apparatus 30 It is determined whether or not the value of the variable “tilt” indicating is less than 180 (step S115).

  When the value of the variable “tilt” indicating the tilt angle is less than 180 (N in step S115), the image processing apparatus 30 adds 0.1 to the value of the variable “tilt” indicating the tilt angle. (Step S116).

  Then, the angle instruction unit 32 of the image processing apparatus 30 instructs the driving unit 14 of the marker 10 to control the angle of the support member 15 to the angle indicated by the value of the variable “tilt” set in the process of step S116. Send. The drive unit 14 of the marker 10 controls the support member 15 to a tilt angle according to an instruction from the image processing device 30. The imaging instruction unit 33 of the image processing apparatus 30 instructs the imaging apparatus 20 to capture a thermal image, and the process proceeds to step S103.

  Further, the image processing apparatus 30 determines the tilt angle when the number of white pixels reaches the maximum value when the value of the variable “tilt” indicating the tilt angle is not less than 180 (Y in step S115). The value of “ANG_T” is set to the value of the variable “tilt” indicating the tilt angle, and p (xc, yc) is set to the coordinate value p of the center coordinate of the white pixel in the image coordinate system (step S118). .

  Next, the value of the variable “ANG_T” indicating the tilt angle when the number of white pixels reaches the maximum value, and the value of the variable “ANG_T” indicating the tilt angle when the number of white pixels reaches the maximum value are set. First, a method for associating the coordinate value p of the image coordinate system with the coordinate value of the world coordinate system will be described. FIG. 8 is an explanatory diagram showing the correspondence between the coordinate values of the image coordinate system and the coordinate values of the world coordinate system.

  As shown in FIG. 8, in the thermal image captured by the imaging device 20 when the marker 10 that was installed when each process shown in FIG. The position of the ground imaged at the position p is a point P.

  Indicates the pan angle when the number of white pixels reaches the maximum value when the marker 10 has a function of measuring the installed position based on a GPS signal received from a GPS (Global Positioning System) satellite. The value of the variable “ANG_P”, the value of the variable “ANG_T” indicating the tilt angle when the number of white pixels reaches the maximum value, and the position where the support member 15 of the marker 10 is supported by the casing of the marker 10 The coordinate value of the point P in the world coordinate system is calculated on the basis of the height from the ground and the position where the marker 10 measured based on the GPS signal is installed. The coordinate value of the calculated world coordinate system of the point P is the coordinate value of the world coordinate system corresponding to the coordinate value p (xc, yc) of the image coordinate system.

  When the marker 10 does not have a function of calculating the position where the marker 10 is installed based on the GPS signal, for example, the variable “ANG_P” indicating the pan angle when the number of white pixels reaches the maximum value. ”, The value of the variable“ ANG_T ”indicating the tilt angle when the number of white pixels reaches the maximum value, and the ground where the support member 15 of the marker 10 is supported by the case of the marker 10. The distance and direction of the point P with respect to the marker 10 are calculated based on the height of.

  Then, the coordinate value of the world coordinate system indicating the position of the point P based on the calculation result is measured based on the signal received from the GPS satellite, or the world coordinate system of the point P with respect to the position of the coordinate value of the known world coordinate system. The coordinate value is measured using a tape measure or a ruler. The coordinate value in the world coordinate system of the measured or surveyed point P is the coordinate value in the world coordinate system corresponding to the coordinate value p (xc, yc) in the image coordinate system.

  Then, by calculating or surveying the coordinate values of the world coordinate system corresponding to the coordinate values of the plurality of image coordinate systems, the position and moving speed of the imaging target of the imaging device 20 can be measured with high accuracy.

  Specifically, in a road monitoring system or the like, high accuracy is achieved by associating the coordinate values of the image coordinate system and the coordinate values of the world coordinate system at a plurality of positions with high accuracy, and linearly interpolating between each position. Thus, the road surface on the world coordinate system can be associated with the road surface on the image coordinate system. Therefore, the position and moving speed of the imaging target of the imaging device 20 can be measured with high accuracy.

  According to this embodiment, the coordinate value p in the image coordinate system of the position used as a reference in the thermal image captured by the imaging device 20 can be calculated with high accuracy.

  Then, the coordinate value of the calculated or surveyed point P in the world coordinate system can be associated with the coordinate value p of the image coordinate system calculated with high accuracy.

  Furthermore, according to the present embodiment, the imaging device 20 captures an image by associating the coordinate value of the image coordinate system with the coordinate value of the world coordinate system in the movement path of the imaging target (for example, an automobile) of the imaging device 20. The position and moving speed of the imaging target can be calculated with high accuracy based on the thermal image.

  Next, an outline of the present invention will be described with reference to the drawings. FIG. 9 is a block diagram showing an outline of the present invention. The reference position calculation system 40 according to the present invention includes a position measurement device 50 (corresponding to the marker 10 shown in FIG. 2), an image processing device 60 (corresponding to the image processing device 30 shown in FIG. 1), and an imaging device 70 (FIG. 1). The image capturing apparatus 20 shown in FIG.

  The position measuring device 50 includes a reflecting member 51 (corresponding to the reflecting plate 11 shown in FIG. 2) and a heat source 52 (corresponding to the heat source 12 shown in FIG. 2). The image processing device 60 includes coordinate value calculation means 61 (corresponding to the coordinate value calculation means 31 shown in FIG. 1).

  The reflecting member 51 reflects far infrared rays. The heat source 52 is installed at a position where the radiated far infrared rays are reflected by the reflecting member 51. The imaging device 70 outputs a thermal image obtained by imaging the position measurement device 50 to the image processing device 60. The coordinate value calculation means 61 calculates the coordinate value in the image coordinate system of the pixel at the center of the region where the intensity of far infrared rays per unit area is equal to or greater than a predetermined value in the thermal image output from the imaging device 70.

  According to such a configuration, the outline of a region in which the intensity of far infrared rays per unit area is a predetermined value or more in the thermal image output by the imaging device 70 is clarified, and the position or moving speed of the imaging target is measured. The coordinate value in the image coordinate system at the center of the area used as the reference can be calculated with high accuracy.

  Moreover, in said embodiment, the reference position calculation system as shown to the following (1)-(4) is also disclosed.

(1) A reference position calculation system in which the inner wall of the reflecting member 51 of the position measuring device 50 is formed in a parabolic shape, and the heat source 52 is installed at a focal position on the paraboloid by the inner wall. In the case of such a configuration, the inner wall of the reflecting member 51 reflects far infrared rays emitted by the heat source 52 in a certain direction, so that the far area per unit area in the thermal image output by the imaging device 70 is reflected. The outline of the region where the intensity of infrared rays is a predetermined value or more can be made clearer.

(2) The position measuring device 50 supports the reflecting member 51 in order to change the area of the region where the intensity of far infrared rays per unit area is a predetermined value or more in the thermal image output by the imaging device 70. An angle control means (corresponding to the drive unit 14 shown in FIG. 2) for changing the angle of the support member (corresponding to the support member 15 shown in FIG. 2) with respect to the horizontal plane and the angle with respect to a predetermined direction in the horizontal plane, However, when the angle control means of the position measuring device 50 changes the angle of the support member of the reflecting member 51 with respect to the horizontal plane or the angle with respect to a predetermined direction in the horizontal plane, the imaging instruction means (instructing imaging to the imaging apparatus 70) 1) and the intensity of far infrared rays per unit area in the thermal image output by the imaging device 70. And an area information generating means (corresponding to the area information generating means 34 shown in FIG. 1) for generating area information indicating the area of the region where is equal to or greater than a predetermined value. Image coordinates of the pixel in the center of the region where the intensity of far infrared rays per unit area is greater than or equal to a predetermined value in the thermal image having the widest area indicated by the area information generated by the area information generating means A reference position calculation system for calculating coordinate values in the system. In such a case, the coordinate value in the world coordinate system corresponding to the calculated coordinate value in the image coordinate system is used as the support member when the thermal image having the widest area indicated by the area information is captured. It is possible to easily calculate based on an angle with respect to a horizontal plane and an angle with respect to a predetermined direction on the horizontal plane.

(3) A reference position calculation system in which the image processing device 60 includes an angle instruction unit that instructs the angle control unit to determine an angle of the support member of the reflecting member 51 with respect to the horizontal plane and an angle with respect to a predetermined direction on the horizontal plane. In the case of such a configuration, the angle of the support member with respect to the horizontal plane and the angle with respect to the predetermined direction in the horizontal plane are changed, that is, the thermal image is displayed according to the change in the angle of the reflection member 51 with respect to the imaging device 70. The imaging device 70 can output the image.

(4) In the thermal image output by the imaging device 70, the coordinate value calculation means 61 has coordinates of both end portions in the X-axis direction of the image coordinate system in a region where the intensity of far infrared rays per unit area is a predetermined value or more. A reference position calculation system that calculates a coordinate value in the middle of the image coordinates and a coordinate value in the middle of the image coordinate system in the Y-axis direction in the region as the coordinate value in the image coordinate system of the center pixel of the region . In the case of such a configuration, the coordinate value in the image coordinate system of the position used as the reference for measuring the position of the imaging target or the moving speed is easily calculated using the thermal image output by the imaging device 70. can do.

  The present invention is applicable to a system used for measuring the position or moving speed of an imaging target based on a thermal image captured by an imaging unit.

DESCRIPTION OF SYMBOLS 10 Marker 11 Reflector 12, 52 Heat source 13 Fixing member 14 Drive part 15 Support member 20, 70 Imaging device 30, 60 Image processing device 31, 61 Coordinate value calculation means 32 Angle instruction means 33 Imaging instruction means 34 Area information generation means 40 Reference position calculation system 50 Position measuring device 51 Reflective member

Claims (7)

A reference position calculation system used for measuring a position or moving speed of an imaging target based on a thermal image,
A position measuring device including a reflecting member that reflects far infrared rays, and a heat source that is installed at a position where the emitted far infrared rays are reflected by the reflecting member;
An imaging device that outputs a thermal image obtained by imaging the position measurement device installed at a position corresponding to a position at which the imaging target is imaged; and
An image processing device including coordinate value calculation means for calculating coordinate values of the position measuring device in an image coordinate system of the thermal image based on the thermal image output by the imaging device;
The coordinate value calculation means of the image processing device is configured to coordinate values in an image coordinate system of a pixel at the center of a region where the intensity of far infrared rays per unit area is equal to or greater than a predetermined value in the thermal image output from the imaging device. A reference position calculation system characterized by calculating. The reference position calculation system according to claim 1, wherein an inner wall of the reflecting member of the position measuring device is formed in a paraboloid shape, and a heat source is installed at a focal position on the paraboloid by the inner wall. The position measuring device
In the thermal image output by the imaging device, in order to change the area of the region where the intensity of far infrared rays per unit area is equal to or greater than a predetermined value, the angle of the support member supporting the reflecting member with respect to the horizontal plane and the predetermined in the horizontal plane Angle control means for changing the angle with respect to the direction of
The image processing device
Imaging instruction means for instructing the imaging apparatus to perform imaging at a timing when the angle control means of the position measuring device changes the angle of the support member of the reflecting member with respect to the horizontal plane or the angle with respect to a predetermined direction on the horizontal plane; ,
In the thermal image output by the imaging device, including area information generating means for generating area information indicating the area of the region,
The coordinate value calculating means has a predetermined far infrared intensity per unit area in a thermal image having the widest area indicated by the area information generated by the area information generating means among the thermal images output by the imaging device. The reference position calculation system according to claim 1, wherein a coordinate value in an image coordinate system of a pixel at a center of a region that is equal to or greater than the value is calculated. The reference position calculation system according to claim 3, wherein the image processing apparatus includes an angle instruction unit that instructs an angle control unit to determine an angle of the support member with respect to the horizontal plane and an angle with respect to a predetermined direction on the horizontal plane. The coordinate value calculation means is a coordinate in the middle of the coordinate values of both ends in the X-axis direction of the image coordinate system in a region where the intensity of far infrared rays per unit area is equal to or greater than a predetermined value in the thermal image output by the imaging device The coordinate value in the middle of the value and the coordinate value of both ends in the Y-axis direction of the image coordinate system in the region is calculated as the coordinate value in the image coordinate system of the center pixel of the region. The reference position calculation system according to any one of the preceding claims. A reference position calculation method for calculating coordinates of a reference position used for measurement of a position or moving speed of an imaging target based on a thermal image,
A position measuring device that includes a reflecting member that reflects far infrared rays and a heat source that is installed at a position where the emitted far infrared rays are reflected by the reflecting member, and is installed at a position corresponding to a position at which the imaging target is imaged In the thermal image captured by the imaging device, in order to change the area of the region where the intensity of the far infrared ray per unit area is a predetermined value or more, the angle of the support member that supports the reflecting member with respect to the horizontal plane and the horizontal plane Change the angle with respect to a predetermined direction at
Instructing the imaging device to perform imaging at a timing when the angle of the support member of the reflecting member with respect to the horizontal plane or the angle with respect to a predetermined direction in the horizontal plane is changed,
In the thermal image output by the imaging device, generate area information indicating the area of the region,
Among the thermal images output by the imaging device, in the thermal image having the widest area indicated by the generated area information, the image coordinates of the pixel in the center of the region where the intensity of far infrared rays per unit area is a predetermined value or more A reference position calculation method characterized by calculating coordinate values in a system. In the thermal image output by the imaging device, the coordinate value in the middle of the coordinate values of both ends in the X-axis direction of the image coordinate system in the region where the intensity of the far infrared ray per unit area is a predetermined value or more, and in the region The reference position calculation method according to claim 6, wherein a coordinate value in the middle of the coordinate values at both ends in the Y-axis direction of the image coordinate system is calculated as a coordinate value in the image coordinate system of the pixel at the center of the region.

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