JP5468689B1 - Imaging apparatus, scale generation method of the imaging apparatus, program, and recording medium - Google Patents

Abstract

An imaging apparatus capable of measuring the size of an observation object when photographing the observation object, having an inexpensive and simple configuration, a scale generation method of the imaging apparatus, a program, and a recording medium are provided. .
An imaging apparatus according to the present invention includes an imaging unit that images an observation target, one or more laser light sources that irradiate laser light in parallel with the imaging direction of the imaging unit, and the laser light. A light spot detecting unit that detects one or more light spots generated on the observation object on the photographed image by the reflection of light and calculates the position of the light spot; and the captured image of the light spot A scale generation unit that calculates a scale width of a scale that is a measure of the size of the observation object in the captured image based on the upper position, and the imaging based on the scale width calculated by the scale generation unit A scale drawing unit that draws the scale on the image; and a display unit that displays the scale drawn on the captured image and the captured image.
[Selection] Figure 1

Description

  The present invention relates to a technique for displaying an image of an observation object and displaying a captured image with a scale serving as a scale of the size of the observation object displayed in the captured image.

  An imaging device that captures an observation target as an observation image as a captured image, and displays the captured image on a display unit such as a liquid crystal display or an organic / inorganic EL (Electro-Luminescence) display in real time, such as an endoscope or digital Cameras, digital video cameras, etc. are in widespread use. In such an imaging apparatus, the reflected light reflected by the object using a lens is imaged on an imaging sensor such as a CCD or CMOS as a subject image, and the imaged subject image is captured as a captured image.

  By the way, when imaging an observation object using such an imaging apparatus, there is a need to know the size of the observation object from the captured image displayed on the display unit simultaneously with the observation. This is, for example, when measuring the size of a crack present in the building when performing a health check of the building, or when evaluating the size of a lesion in observation inside the body using an endoscope, etc. Applicable.

  In order to satisfy such needs, for example, in Patent Document 1, when an observation object is observed using an imaging device, a distance between the observation object and the laser distance meter is measured using a laser distance meter. In addition, the scale light including the length or area information is projected onto the observation object, and the length or area information included in the scale light in the captured image is calibrated based on the measured distance. Techniques have been proposed that use scale light as a measure of the size of an observation object.

  In Patent Document 2, when observing an observation object with an endoscope, a treatment member such as a forceps provided with an index serving as a length scale is reflected in the captured image, and is moved into the captured image. On the other hand, there has been proposed a technique for displaying a scale serving as a scale of the size of an observation object in a captured image based on an index.

  Furthermore, in Patent Document 3, the observation target is irradiated with laser light, and the distance between the observation target and the imaging device tip is measured based on the reflected light intensity of the laser light. Based on this, a technique has been proposed in which a scale that is a scale of the size of an observation object is drawn and displayed on a captured image.

JP 2001-280960 A JP2008-194156 JP2011-69965

  However, the techniques proposed in Patent Document 1 to Patent Document 3 described above have the following problems.

  In the technique described in Patent Document 1, there is a problem that a laser distance meter, a projector, and the like are necessary, and the configuration is complicated and the cost is increased. In addition, since the size of the object to be observed is obtained using scale light as a scale, there is a problem that precise measurement is difficult.

  In the technique described in Patent Document 2, since the scale is displayed based on the index provided on the treatment member, it is necessary to arrange the treatment member so as to move into the captured image, and there is a problem that the operation is complicated and difficult to handle.

  In the technique described in Patent Document 3, it is necessary to split the laser light for distance measurement and the light including video information, and further simplification of the configuration is required for cost reduction.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an imaging apparatus that can measure the size of an observation object and that is inexpensive and has a simple configuration, a scale generation method for the imaging apparatus, a program, and a recording medium.

In order to achieve the above object, an imaging apparatus according to the present invention includes an imaging unit that captures an observation object as a captured image, a laser beam that is irradiated in parallel with the imaging direction of the imaging unit, and the center of the imaging unit. Two or more laser light sources fixed so as to be arranged around the imaging unit at an equal distance from the unit, and two or more generated by overlapping the observation object on the photographed image by reflection of the laser light detecting the light point, the light spot detection section for calculating a position on the captured image of the light spot, based on the position on the two or more light spots of the captured image, the imaging with the light spot A reference point interval calculation unit for calculating an interval between the center of the image and two or more of the light spots detected by the light spot detection unit are arranged on the same straight line passing through the center of the captured image. predetermined computational at the reference point interval calculator for two light spots was And on the basis of the interval, the maximum value of the interval, the minimum value and the observation object of the imaging in the image at a distance from the tip of the imaging apparatus corresponding to any value of their average value magnitude of The scale width of the scale as a scale, geometrically, or the correspondence between the distance between the position of the intersection and the center of the captured image, and the distance between the observation object and the tip of the imaging device A facing scale width calculation unit that calculates using the distance calibration data indicating , and among the angles formed by the imaging surface of the imaging device and the observation object based on the interval, the height direction in the captured image or With respect to the scale width calculated by the tilt angle calculation unit that calculates the angle in the width direction as the vertical tilt angle or the horizontal tilt angle, and the straight scale width calculation unit based on the vertical tilt angle or the horizontal tilt angle, respectively. Teo In order to perform correction, a matrix calculation unit for calculating a projective transformation matrix for projective transformation of the scale based on the vertical or horizontal tilt angle calculated by the tilt angle calculation unit, and the facing scale width calculation unit A scale width correction unit that includes a projection correction unit that corrects the scale width calculated in step S, based on the projective transformation matrix, and the scale on the captured image based on the scale width calculated by the scale width correction unit. And a scale drawing unit for drawing the image, and a display unit for displaying the scaled image overlaid on the captured image and the captured image on which the distortion correction of the image is not performed.

Further, the scale generation method of the present invention captures an observation object as a captured image, and displays the captured image and a scale that is a scale of the size of the observation object drawn on the captured image. A method for generating the scale of an apparatus, wherein the imaging apparatus is fixed so that the imaging apparatus is irradiated with laser light in parallel with an imaging direction and is arranged around the imaging object at an equal distance from the center of the imaging unit. from two or more laser sources to detect two or more light spots generated superimposed on the observed object on the captured image and the irradiation step, the reflection of the laser light irradiating the laser beam, a light spot detecting step of calculating the position on the captured image of the light spot, based on the position on the two or more light spots of the captured image, between the center of the light spot and the captured image reference point interval calculation to calculate the interval Step and, among the two or more of the light spot detected by the light spot detecting step, said reference point intervals calculated for a given two light spots that are arranged on the same straight line passing through the center of the captured image The observation object in the captured image at a distance from the tip of the imaging device corresponding to any one of the maximum value, the minimum value, and the average value of the interval based on the interval calculated in the step The scale width of the scale, which is a measure of the size of the object, is determined geometrically or between the position of the intersection and the center of the captured image, and between the observation object and the tip of the imaging device. In the captured image, out of the angles formed by the imaging surface of the imaging device and the observation object based on the interval, a directly-facing scale width calculation step that calculates using distance calibration data indicating a correspondence relationship with the distance Height direction at or A tilt angle calculating step of calculating a direction of an angle as a longitudinal tilt angle or transversely tilt angle, respectively, with respect to the scale width calculated by the confronting scale width calculation step, based on the vertical tilt angle or the horizontal tilt angle Matrix calculation step for calculating a projective transformation matrix for projective transformation of the scale based on the vertical tilt angle or the horizontal tilt angle calculated by the tilt angle calculation unit to perform tilt correction, and the straight scale width calculation A scale width correction step comprising a projection correction step for correcting the scale width calculated in the section based on the projection transformation matrix, and the distortion correction of the image based on the scale width calculated in the scale width correction step. And a scale drawing step of drawing the scale on the captured image that has not been performed.

Further, the scale generation program of the present invention and the recording medium on which the program is recorded are irradiated with laser light in parallel with the imaging direction and arranged around the imaging object at an equal distance from the center of the imaging unit. Two or more laser light sources fixed to the image, the observation object is imaged as a captured image, and a scale serving as a scale for the size of the observation object drawn on the captured image and the captured image A scale generation program for drawing the scale on the imaging device to be displayed, and a recording medium on which the program is recorded, wherein two or more generated on the observation object on the captured image by the reflection of the laser light A light spot detection procedure for detecting a light spot, a light spot position calculation procedure for calculating a position of the light spot detected in the light spot detection procedure on the captured image, and a light spot position calculation procedure. On the basis of the light spot position, and the reference point interval calculation procedure for calculating the distance between the center point of the light spot and the captured image, the laser beam from at least two of the laser light source is irradiated, Of the two or more light spots detected and calculated in the light spot position calculation procedure and the light spot position calculation procedure, on the same straight line passing through the center of the captured image. Based on the interval calculated in the reference point interval calculation procedure for the two predetermined light spots arranged , the maximum value corresponding to any one of the maximum value, the minimum value, and the average value thereof The scale width of the scale, which is a measure of the size of the observation object in the captured image at a distance from the tip of the imaging device, is geometrically or between the position of the intersection and the center of the captured image. The interval, the observation object and the And confronting the scale width calculation procedure for calculating by using the distance calibration data showing a correspondence relationship between the distance between the tip of the image device, the observation object to the imaging plane of the imaging device is formed on the basis of the distance Of the angles, a tilt angle calculation procedure for calculating a height direction or a width direction angle in the captured image as a vertical tilt angle or a horizontal tilt angle, respectively, and the straight facing based on the vertical tilt angle or the horizontal tilt angle. A projective transformation matrix for projectively transforming the scale based on the vertical or horizontal tilt angle calculated by the tilt angle calculation unit in order to perform tilt correction on the scale width calculated in the scale width calculation procedure. A matrix calculation procedure for calculating the scale width correction procedure, and a scale width correction procedure comprising a projection correction procedure for correcting the scale width calculated by the facing scale width calculation unit based on the projective transformation matrix ; Based on the scale width calculated in the scale width correction procedure, causing the imaging device to execute a scale drawing procedure for drawing the scale on the captured image that has not been subjected to image distortion correction. It is characterized by.

  According to the present invention, a light spot generated by irradiating a laser beam on an observation object is detected from a captured image, and a scale serving as a measure of the size of the observation object is obtained based on the position of the detected light spot. Draw on the captured image.

  Thus, in the present invention, the light spot reflected in the captured image is detected, the scale width is calculated based on the position of the light spot, and the scale is drawn on the captured image. Therefore, it is possible to measure the size of the observation object while observing.

  In addition, since a special measuring device such as a laser distance meter is unnecessary, the configuration of the imaging device is simplified and can be provided at low cost.

1 is a block diagram illustrating a configuration of an imaging apparatus according to a first embodiment of the present invention. It is a block diagram which shows the detailed structure of the scale production | generation part 140 shown in FIG. FIG. 2 is a conceptual diagram illustrating an example of an imaging device 100 illustrated in FIG. 1 and a captured image captured by the imaging device 100. It is a conceptual diagram explaining operation | movement of the imaging device 100 shown in FIG. It is a conceptual diagram explaining the operation principle of the imaging device 100 shown in FIG. FIG. 4 is an image diagram of a captured image in which a scale is drawn by the imaging apparatus 100 illustrated in FIG. 3. It is a block diagram which shows the structure of the imaging device of the 2nd Embodiment of this invention. It is a block diagram which shows the detailed structure of the scale production | generation part 180 shown in FIG. It is a block diagram which shows the detailed structure of the scale correction | amendment part 185 shown in FIG. FIG. 8 is a conceptual diagram illustrating an example of a captured image captured by the imaging device 101 and the imaging device 101 illustrated in FIG. 7. It is a conceptual diagram explaining operation | movement of the imaging device 101 shown in FIG. It is a conceptual diagram explaining the principle of operation of the imaging device 101 shown in FIG. It is an image figure of the captured image by which the scale was drawn with the imaging device 101 shown in FIG. It is a block diagram which shows the structure of the imaging device of the 3rd Embodiment of this invention. It is a block diagram which shows the detailed structure of the scale production | generation part 190 shown in FIG. It is a block diagram which shows the detailed structure of the scale correction | amendment part 195 shown in FIG. It is a conceptual diagram which shows an example of the captured image imaged with the imaging device 102 and the imaging device 102 shown in FIG. It is an image figure of the captured image by which the scale was drawn with the imaging device 102 shown in FIG.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

(First embodiment)
FIG. 1 is a block diagram showing a configuration of an imaging apparatus according to the first embodiment of the present invention.
As illustrated in FIG. 1, the imaging apparatus 100 according to the present embodiment includes a laser light source 110, an imaging unit 120, a light spot detection unit 130, a scale generation unit 140, a distance calculation unit 150, and a scale drawing unit 160. And a display unit 170. Although not illustrated in FIG. 1, the imaging apparatus 100 also includes an operation unit and the like for the user to operate each component.

  The imaging unit 120 captures an observation object as a captured image from the tip of the imaging device 100. Although not shown in FIG. 1, the imaging unit 120 includes an imaging sensor such as a CCD or a CMOS, an optical system for guiding light to form an observation object on the imaging sensor, and the like. . In addition, the imaging unit 120 can repeat imaging at a predetermined frame rate or can take an image with a snapshot.

  The laser light source 110 is disposed so as to irradiate laser light from the front end of the imaging device 100 in parallel with the imaging direction of the imaging unit 120, irradiates the observation target with laser light, and emits a light spot on the observation target. Give rise to Although not illustrated in FIG. 1, the laser light source 110 includes a laser oscillator and an optical system for irradiating a laser in the imaging direction of the imaging unit 120 from the tip of the imaging device 100. In addition, although one laser light source 110 is provided here, two or more laser light sources 110 may be provided. The wavelength of the laser light that the laser light source 110 irradiates the observation object needs to be in a wavelength region that can be imaged as a captured image by the imaging unit 120, and a general imaging sensor such as CCD or CMOS is used for the imaging unit 120. When used, the wavelength range is preferably 380 nm to 780 nm.

  The light spot detection unit 130 detects a light spot generated on the observation object on the photographed image captured by the imaging unit 120 by the reflection of the laser light emitted from the laser light source 110, and the captured image of the light spot. Calculate the top position. Note that, here, since one laser light source 110 is provided, only one light spot is reflected on the captured image. However, when two or more laser light sources 110 are provided, two or more laser light sources 110 are included on the captured image. A light spot is reflected. In that case, the light spot detection unit 130 detects two or more light spots reflected on the captured image, and calculates the positions on the captured image.

  The scale generation unit 140 is a scale that is a measure of the size of the observation object in the captured image based on the position of the one or more light spots calculated by the light spot detection unit 130 on the captured image. Calculate the scale width.

  The scale drawing unit 160 draws the scale on the captured image based on the scale width calculated by the scale generation unit 140.

  The display unit 170 displays a scale drawn on the captured image and the captured image. As a result, the display unit 170 displays a captured image on which a scale serving as a scale of the size is drawn. Therefore, the user of the imaging apparatus 100 accurately measures the size of the observation object using the scale as a scale. It becomes possible to do.

FIG. 2 is a block diagram showing a detailed configuration of the scale generation unit 140 shown in FIG.
As illustrated in FIG. 2, the scale generation unit 140 includes a reference point interval calculation unit 141 and a scale width calculation unit 142.

  The reference point interval calculator 141 calculates the interval between the light spot and the reference point on the captured image based on the position of one or more light spots calculated by the light spot detector 130. The center of the captured image can be used as the reference point.

  The scale width calculation unit 142 is based on the interval between the light spot calculated by the reference point interval calculation unit 141 and the reference point, and the observation in the captured image at the distance from the tip of the imaging apparatus 100 corresponding to the interval. The scale width of the scale, which is a measure of the size of the object, is calculated.

  In addition, the distance calculation unit 150 illustrated in FIG. 1 is based on the distance between the light spot calculated by the reference point interval calculation unit 141 and the reference point, and the distance between the tip of the imaging device 100 and the observation object. Calculate Note that the distance calculation unit 150, when the reference point interval calculation unit 141 calculates two or more light spots, is one of the maximum, minimum, and average value of the calculated intervals. Use the value to calculate the distance.

  The distance value calculated by the distance calculation unit 150 is drawn by the scale drawing unit 160 in a superimposed manner at a predetermined position on the captured image. Accordingly, since the distance to the observation target is displayed on the display unit 170, the user of the imaging apparatus 100 can recognize the distance to the observation target.

FIG. 3 is a conceptual diagram illustrating an imaging device 100 (left diagram) and an example (right diagram) of a captured image captured by the imaging device 100.
FIG. 4 is a conceptual diagram showing the operation of the imaging apparatus 100 shown in FIG.
FIG. 5 is a conceptual diagram showing the principles of scale generation and distance measurement in the imaging apparatus 100 shown in FIG.
The operation of the imaging apparatus 100 will be described with reference to FIGS. 3, 4, and 5. Here, the center of the captured image is used as a reference point.

  As shown in the left diagram of FIG. 3, in the imaging apparatus 100 of the present embodiment, the laser light source 110 is fixed so as to irradiate the observation target with laser light in parallel with the imaging direction of the imaging unit 120 that images the observation target. Installed. In addition, the form shown in FIG. 3 is an example, and is not limited to this form. For example, the position of the laser light source 110 may not be directly beside the imaging unit 120 but may be installed at a position directly above or on a diagonal line of the captured image. For example, it is good also as a form which irradiates a laser with respect to an imaging direction from the front-end | tip of an endoscope.

  As shown in the right diagram of FIG. 3, the captured image when the observation object is imaged by such an imaging apparatus 100 includes a light spot generated on the observation object by the laser light 200 emitted from the laser light source 110. A is reflected as light spot A '.

  The light spot detection unit 130 detects the light spot A ′ reflected in the captured image, and calculates the center of gravity as the position of the light spot A ′.

  The reference point interval calculation unit 141 calculates the interval d1 between the position of the light spot A ′ calculated by the light spot detection unit 130 and the center of the captured image as the reference point.

  As shown in the upper diagram of FIG. 4, when the distance between the imaging device 100 and the observation object 300 is a long distance, the light spot A generated on the observation object is close to the center on the captured image. Detected by position. For this reason, the distance d1 between the reference point and the light spot A 'is shortened.

On the other hand, as shown in the lower diagram of FIG. 4, when the distance between the imaging device 100 and the observation object 300 is a short distance, the light spot A generated on the observation object is It is detected at a position close to the outer periphery. Therefore, the distance d1 between the reference point and the light spot A ′ becomes long.
As described above, the position of the light spot A ′ detected on the captured image changes according to the distance between the imaging device 100 and the observation object 300.

  Here, as shown in FIG. 5, when the distance from the center of the imaging unit 120 to the laser irradiation port of the laser light source 110 is α, the laser light 200 is highly linear, so the tip of the imaging device 100 and the observation object Since the distance α is always substantially constant even if the distance between them changes, the correspondence between the length on the captured image and the length in the real space is α / d1 due to the geometric relationship. Thereby, it is possible to know the correspondence between one pixel in the captured image and the length in the real space at the tip of the imaging device 100, strictly speaking, the distance from the tip of the imaging device 120 to the light spot A.

  In the scale width calculation unit 142, by using such a geometrical relationship, based on the interval between the light spot A and the reference point calculated by the reference point interval calculation unit 141, it corresponds to the interval. The scale width of the scale, which is a measure of the size of the observation object in the captured image at a distance from the tip of the imaging device 100, is calculated.

  As shown in FIG. 5, if the angle of view of the imaging unit 120 is 2θ, and the width of the captured image focused on the imaging surface by the optical system in the imaging unit 120 is 2w, the object to be observed from the front end of the imaging device 100. The distance from the tip of the imaging unit 120 to the A light spot generated on the object to be observed more precisely is (α / tan θ) [{(w−d1) / d1} + 1].

  In the distance calculation unit 150, by using such a geometrical relationship, the front end of the imaging device 100 and the observation are based on the interval between the light spot A and the reference point calculated by the reference point interval calculation unit 141. The distance between the objects is calculated.

  Note that when the distance between the observation object 300 and the tip of the imaging device 100 is shorter than the predetermined distance, the light spot A is generated outside the range that can be imaged by the imaging device 100, so that the light spot detection unit 130 captures an image. The light spot A ′ cannot be detected from the image.

  More specifically, as shown in FIG. 5, the light spot A is imaged by the imaging unit 120 when the distance between the observation object 300 and the tip of the imaging device 100 is shorter than α / tanθ due to the geometric relationship. This occurs outside the possible range, and the light spot A ′ cannot be detected by the light spot detector 130.

  In the present invention, in addition to the geometric method shown in FIG. 5, the distance between the position of the light spot and the reference point of the captured image, and between the observation object and the tip of the imaging device. The scale width of the scale may be calculated using distance configuration data indicating the correspondence with the distance. The method is as follows.

  As shown in FIG. 4, the position of the light spot A detected on the captured image changes according to the distance between the imaging device 100 and the observation object 300. Therefore, distance calculation data indicating a correspondence relationship between the distance d1 and the distance between the imaging device 100 and the observation object 300 is obtained in advance, and the distance calibration data is stored in the storage device, so that the distance calculation unit At 150, the distance between the imaging device 100 and the observation object 300 can be calculated from the interval d1. Here, in order to exchange data between the scale generation unit 140 and the distance calculation unit 150, the storage device may be provided as an auxiliary device of either of them, or may be independent of both. It may be provided as a storage unit.

  As the next step, the scale calibration data indicating the correspondence between one pixel in the captured image at each distance and the length in the real space is obtained in advance, and stored in the storage device or the storage unit. Based on the distance calculated by the calculation unit 142 and the scale calibration data, the scale can be drawn on the captured image.

  FIG. 6 is an image diagram of a captured image drawn with scales drawn by the scale drawing unit 160, and shows an image in which a crack on the observation target is inspected using the image pickup apparatus 100.

  As shown in FIG. 6, by drawing a scale on the captured image, the size of the crack can be measured using the scale as a scale. Also, as shown in FIG. 6, by drawing the calculated distance between the tip of the imaging apparatus 100 and the observation target on the captured image, the user of the imaging apparatus 100 can determine the distance to the observation target. The size of the crack on the observation object can be easily known.

  In FIG. 6, the scale shape is drawn as a cross scale, but the present invention is not limited to this, and may be a grid scale, for example. Further, a scale that has been corrected in consideration of distortion by the optical system of the imaging unit 120 may be drawn.

Next, the effect of the present embodiment will be described.
As described above, according to the imaging apparatus 100 of the present embodiment, the position on the captured image of the light spot generated on the observation object by the laser light emitted from the laser light source 110 is calculated, and the image on the captured image is displayed. A scale serving as a measure of the size of the observation object at a distance corresponding to the distance between the reference point and the light spot can be drawn on the captured image and displayed on the display unit 170.

  Therefore, in the imaging apparatus 100 according to the present embodiment, the size of the observation object can be measured using the scale drawn on the captured image as a scale while observing the observation object.

  In addition, the imaging apparatus 100 according to the present embodiment has a simple configuration, and can be configured using, for example, a PC, a web camera, a laser pointer, and the like. can do.

  Furthermore, in the imaging apparatus 100 of the present embodiment, the distance from the tip of the imaging apparatus 100 to the observation object is calculated based on the interval between the reference point on the captured image and the light spot, and displayed on the display unit 170. can do. Thus, the distance to the observation object can be recognized while observing the observation object.

(Second Embodiment)
FIG. 7 is a block diagram illustrating a configuration of an imaging apparatus according to the second embodiment of the present invention.
As illustrated in FIG. 7, the imaging apparatus 101 according to the present embodiment is different from the imaging apparatus 100 according to the first embodiment illustrated in FIG. The difference is that a scale generation unit 180 is provided instead of the unit 140. The other components are the same as those of the imaging device 100 shown in FIG. In addition, although the two laser light sources 110 and 111 are provided as the minimum necessary configuration here, two or more laser light sources may be provided.

  Similarly to the laser light source 110, the laser light source 111 is disposed so as to irradiate laser light in parallel with the imaging direction of the imaging unit 120 from the tip of the imaging device 101, and irradiates the observation target with laser light. A light spot is generated on the observation object.

  The scale generation unit 180 is based on the interval between the two or more light spots calculated by the reference point interval calculation unit 141 and the reference point on the captured image, from the tip of the imaging device 101 corresponding to the interval. A scale width that is a scale of the size of the observation object in the captured image at a distance is calculated.

FIG. 8 is a block diagram showing a detailed configuration of the scale generation unit 180 shown in FIG.
As illustrated in FIG. 8, the scale generation unit 170 includes a scale width calculation unit 182 instead of the scale width calculation unit 142 as compared with the scale generation unit 140 illustrated in FIG. 2.
Further, the scale width 182 includes a directly-facing scale width calculation unit 183, a tilt angle calculation unit 184, and a scale width correction unit 185.

  The scale width calculation unit 182 is an interval between the reference point calculated by the reference point interval calculation unit 141 with respect to two predetermined light points among the two or more light points detected by the light point detection unit 130. Based on the above, a scale width that is a measure of the size of the observation object in the captured image at a distance corresponding to the interval is calculated in consideration of the angle formed between the imaging surface of the imaging device 101 and the observation object. .

  The directly-facing scale width calculation unit 183 is a reference on the captured image calculated by the reference point interval calculation unit 141 with respect to two predetermined light spots among the two or more light spots detected by the light spot detection unit 130. Based on the distance between the points, the size of the observation object in the captured image at a distance from the tip of the imaging device 101 corresponding to any one of the maximum value, the minimum value, and the average value of the distances Calculate the scale width of the scale, which is a measure of height.

  The tilt angle calculation unit 184 is an interval between the reference point calculated by the reference point interval calculation unit 141 for two predetermined light points among the two or more light points detected by the light point detection unit 130. Based on the above, among the angles formed by the imaging surface of the imaging apparatus 101 and the observation object, the angle in the height direction or the width direction in the captured image is calculated as a vertical tilt angle or a horizontal tilt angle.

  The scale width correction unit 185 performs tilt correction on the scale width calculated by the directly-facing scale width calculation unit 183 based on the vertical tilt angle or the horizontal tilt angle calculated by the tilt angle calculation unit 184.

FIG. 9 is a block diagram showing a detailed configuration of the scale width correction unit 185 shown in FIG.
As illustrated in FIG. 9, the scale width correction unit 185 includes a matrix calculation unit 186 and a projection correction unit 187.

  The matrix calculation unit 186 calculates a projective transformation matrix for projectively transforming the scale based on the vertical tilt angle or the horizontal tilt angle calculated by the tilt angle calculation unit 184.

  The projection correction unit 187 corrects the scale width calculated by the directly-facing scale width calculation unit 183 based on the projection transformation matrix calculated by the matrix calculation unit 186.

FIG. 10 is a conceptual diagram illustrating an example of the imaging device 101 (left diagram) and a captured image (right diagram) captured by the imaging device 101.
FIG. 11 is a conceptual diagram showing the operation of the imaging apparatus 101 shown in FIG.
FIG. 12 is a conceptual diagram illustrating the principle of scale generation in consideration of the tilt angle in the imaging apparatus 101 illustrated in FIG.
The operation of the imaging apparatus 101 will be described with reference to FIGS. 10, 11, and 12. Here, the center of the captured image is assumed to be the reference point.

  As shown in the left diagram of FIG. 10, in the imaging apparatus 101 of the present embodiment, the laser light source 110 and the laser are irradiated so as to irradiate the observation target with laser light in parallel with the imaging direction of the imaging unit 120 that images the observation target. The light source 111 is fixedly installed so that a straight line connecting them passes through the center of the captured image and is parallel to the width direction of the captured image. Further, it is assumed that the laser light sources 110 and 111 are equidistant from the center of the imaging unit 120.

  As shown in the right diagram of FIG. 10, the captured image when the observation target is imaged by such an imaging apparatus 101 includes light spots generated on the observation target by the laser light emitted from the laser light source 110. The light spots from the laser light emitted from the laser light source 121 are reflected as light spots B ′ and C ′, respectively.

  In the light spot detection unit 130, the light spot B 'and the light spot C' reflected in the captured image are detected and their positions are calculated.

In the reference point interval calculator 141, based on the calculated position light spot detection section 130, the light spot B fancy-through in the captured image 'and point C' and the center of which is an imaging image reference point The intervals d2 and d3 are calculated respectively. In addition, since the imaging apparatus 101 shown in the left diagram of FIG. 10 has only two laser light sources 110 and 111, the light spots B ′ and C ′ generated by irradiating them have predetermined two values. One light spot.

  At this time, as shown in the upper diagram of FIG. 11, when the positional relationship between the imaging device 101 and the observation object 300 is facing each other, the light spot B and the light spot C generated on the observation object are captured. On the image, it is detected at a symmetrical position with the center as the boundary. Therefore, the interval d2 and the interval d3 have the same length.

  On the other hand, as shown in the lower diagram of FIG. 11, when the positional relationship between the imaging device 101 and the observation object 300 is not directly opposed, the light spot B and the light spot C generated on the observation object are captured. On the image, it is detected at an untargeted position with the center as the boundary. Therefore, the distances d2 and d3 between the light spot B ′, the light spot C ′, and the reference point in the captured image table have different lengths.

  Thus, the relationship between the lengths of the distances d2 and d3 changes according to the positional relationship between the imaging device 101 and the observation object 300.

  Therefore, the tilt angle calculation unit 184 calculates the angle between the observation object 300 and the imaging device 101 based on the interval d2 and the interval d3, and can use it as the tilt angle of the scale to be drawn. In addition, when the laser light source 110 and the laser light source 111 are installed at positions as shown in FIG. 10, it is possible to calculate the tilt angle in the width direction in the captured image. When calculating the tilt angle in the height direction, the laser light sources 110 and 111 need to be fixedly installed so that the straight line connecting them is parallel to the height direction of the captured image.

More specifically, as shown in FIG. 12, in the case of the imaging apparatus 101 shown in the left diagram of FIG. 10, if the angle of view of the imaging unit 120 is 2θ and the width of the captured image is 2w, the geometric relationship Of the angles formed by the imaging surface of the imaging apparatus 101 and the observation object 300, the lateral tilt angle ξ, which is the angle in the width direction in the captured image, is tan ⁻¹ [(1/2 tan θ) × {(w−d2) / d2 − (W−d3) / d3}]. Here, since θ and w are unique values of the imaging unit 120, it can be seen that the lateral tilt angle ξ can be calculated based on the interval d2 and the interval d3.

  Note that the above-described example is an example, and the geometrical relationship changes according to the arrangement of the imaging unit 120 and the laser light sources 110 and 111 and the position of the reference point in the imaging apparatus 101, so that the form of the calculation formula also changes. However, in the calculation formula, the value changes according to the positional relationship between the imaging surface of the imaging device 101 and the observation object only in the interval between the two light spots and the reference point, and is necessary for other calculations. Since these parameters are device-specific values, the tilt angle can be calculated if the distance between the two light spots and the reference point is known, as in the above example.

  FIG. 13 is an image diagram of a captured image drawn with scales drawn by the scale drawing unit 160, and illustrates the case where a crack on the observation target is inspected using the imaging device 101.

  As shown in FIG. 13, by drawing a scale on the captured image, the size of the crack can be measured using the scale as a scale. In the present embodiment, since the scale in consideration of the horizontal tilt angle is drawn as compared with the image diagram of the captured image in which the scale is drawn by the imaging apparatus 100 of the first embodiment shown in FIG. First, the size of the crack in the width direction in the captured image can be measured more accurately than the imaging apparatus 100 of the first embodiment.

  Further, as shown in FIG. 13, by drawing the calculated distance between the tip of the imaging device 101 and the observation target on the captured image, the user of the imaging device 101 can determine the distance to the observation target. The size of the crack on the observation object can be easily known.

  In FIG. 13, the scale shape is drawn as a cross scale, but the present invention is not limited to this, and may be a grid scale, for example. Further, a scale that has been corrected in consideration of distortion by the optical system of the imaging unit 120 may be drawn.

Next, the effect of the present embodiment will be described.
As described above, according to the imaging apparatus 101 of the present embodiment, the positions on the captured image of the light spots generated on the observation object by the laser light emitted from the laser light source 110 and the laser light source 111 are calculated. Observation in consideration of the tilt angle in the height direction or the width direction in the picked-up image among the angles formed by the image pickup surface of the image pickup apparatus 101 and the observation object based on the interval between the light spot of the image pickup and the reference point on the picked-up image A scale serving as a scale of the size of the object can be drawn on the captured image and displayed on the display unit 170.

  Therefore, in addition to the same effect as the imaging device 100 of the first embodiment, a scale that takes into account the tilt angle in the height direction or the width direction in the captured image drawn on the captured image as compared with the imaging device 100 is used as a scale. The size of the observation object can be measured more accurately.

  As described above, the imaging apparatus 101 according to the present embodiment can easily correct the scale width even when the imaging apparatus does not face the object to be observed, and is extremely useful for drawing an accurate scale. is there.

  In addition, the imaging apparatus 101 of the present embodiment has a simple configuration, and can be configured using, for example, a PC, a web camera, a laser pointer, and the like, and therefore, provided at a lower cost than the conventional technology. Can do.

  Therefore, the imaging apparatus of the present embodiment can obtain a great effect on cost reduction as compared with the conventional one. For example, when the imaging apparatus described in Patent Document 3 is tilted without facing directly to the observation target portion, two or more lasers are installed to obtain the tilt angle (tilt angle) and measure the distance. Although it is necessary to correct the value, there is a limit to reducing the cost of the imaging apparatus because it includes a plurality of laser distance meters. This problem can be solved by the present embodiment that does not require an expensive laser rangefinder.

(Third embodiment)
FIG. 14 is a block diagram illustrating a configuration of an imaging apparatus according to the third embodiment of the present invention.
As shown in FIG. 14, the imaging device 102 of the present embodiment is different from the imaging device 101 of the second embodiment shown in FIG. 7 in that it has laser light sources 112 and 113 and the scale generation unit 180. Instead, the difference is that the scale generation unit 190 is provided. The other components are the same as those of the imaging device 101 shown in FIG. In this example, the laser light sources 110, 111, 112, and 113 are provided as the minimum necessary configuration, but four or more laser light sources may be provided.

  Similarly to the laser light sources 110 and 111, the laser light sources 112 and 113 are arranged so as to irradiate laser light in parallel with the imaging direction of the imaging unit 120 from the tip of the imaging device 102, and laser light is applied to the observation object. To produce a light spot on the observation object. Further, it is assumed that at least one of the laser light sources 110, 111, 112, and 113 is not located on the same straight line.

  The scale generation unit 190 is based on the interval between the four or more light spots calculated by the reference point interval calculation unit 141 and the reference point on the captured image, from the tip of the imaging device 101 corresponding to the interval. A scale width that is a scale of the size of the observation object in the captured image at a distance is calculated.

FIG. 15 is a block diagram showing a detailed configuration of the scale generation unit 190 shown in FIG.
As illustrated in FIG. 15, the scale generation unit 190 includes a scale width calculation unit 192 instead of the scale width calculation unit 182 as compared with the scale generation unit 180 illustrated in FIG. 7.

  The scale width 192 includes a directly-facing scale width calculation unit 193, a tilt angle calculation unit 194, and a scale width correction unit 195.

  The scale width calculation unit 192 calculates the reference point calculated by the reference point interval calculation unit 141 for two predetermined two light points among the four or more light points detected by the light point detection unit 130. Based on the interval between them, the scale width, which is a measure of the size of the observation object in the captured image at a distance corresponding to the interval, is taken into account the angle between the imaging surface of the imaging device 102 and the observation object. To calculate.

  The directly-facing scale width calculation unit 193 is a captured image calculated by the reference point interval calculation unit 141 with respect to two sets of two predetermined light spots among the four or more light spots detected by the light spot detection unit 130. Based on the distance from the upper reference point, the observation target in the captured image at a distance from the tip of the imaging device 102 corresponding to any one of the maximum value, the minimum value, and the average value of the distance Calculate the scale width of the scale, which is a measure of the size of the object.

  The tilt angle calculation unit 194 calculates the reference point calculated by the reference point interval calculation unit 141 for two predetermined two light points among the four or more light points detected by the light point detection unit 130. Among the angles formed by the imaging surface of the imaging apparatus 102 and the observation object based on the interval between them, the angles in the height direction and the width direction in the captured image are calculated as a vertical tilt angle and a horizontal tilt angle, respectively.

  The scale width correction unit 195 performs tilt correction on the scale width calculated by the directly-facing scale width calculation unit 193 based on the vertical tilt angle and the horizontal tilt angle calculated by the tilt angle calculation unit 194.

FIG. 16 is a block diagram showing a detailed configuration of the scale width correction unit 195 shown in FIG.
As illustrated in FIG. 16, the scale width correction unit 195 includes a matrix calculation unit 196 and a projection correction unit 197.

  The matrix calculation unit 196 calculates a projective transformation matrix for projective transformation of the scale based on the vertical and horizontal tilt angles calculated by the tilt angle calculation unit 194.

  The projection correction unit 197 corrects the scale width calculated by the directly-facing scale width calculation unit 193 based on the projection transformation matrix calculated by the matrix calculation unit 196.

FIG. 17 is a conceptual diagram illustrating an example of the imaging device 102 (left diagram) and a captured image (right diagram) captured by the imaging device 102.
The operation of the imaging apparatus 102 will be described with reference to FIG. Here, the center of the captured image is assumed to be the reference point.

  As shown in the left diagram of FIG. 17, in the imaging apparatus 102 of the present embodiment, the laser light sources 110 and 111 are configured to irradiate the observation target with laser light in parallel with the imaging direction of the imaging unit 120 that images the observation target. 112, 113, and the laser light source 110 and the laser light source 111 are fixedly installed so that a straight line connecting them passes through the center of the captured image and is parallel to the width direction of the captured image. Further, the laser light source 112 and the laser light source 113 are fixedly installed so that a straight line connecting them passes through the center of the captured image and is parallel to the height direction of the captured image. The laser light sources 110, 111, 112, and 113 are assumed to be equidistant from the center of the imaging unit 120.

As shown in the right diagram of FIG. 17, the captured image when the observation object is imaged by such an imaging device 102 is displayed on the observation object by the laser light emitted from the laser light sources 110, 111, 112, 113. Are reflected as light spots B ′, C ′, D ′, and E ′, respectively.

  The light spot detection unit 130 detects light spots B ′, C ′, D ′, and E ′ reflected in the captured image and calculates their positions.

  In the reference point interval calculation unit 141, based on the position calculated by the light point detection unit 130, the captured image is the light spots B ′, C ′, D ′, E ′ reflected in the captured image and the reference point. , D2, d3, d4, and d5 are calculated respectively. 11 has only four laser light sources 110, 111, 112, and 113. Therefore, light spots B ′ and C ′ generated by irradiation from these laser light sources 110, 111, 112, and 113 are provided. , D ′, E ′, the combination of the light spots B ′, C ′ and the light spots D ′, E ′ becomes two predetermined two light spots.

  The intervals d2, d3, d4, and d5 change according to the distance and the positional relationship between the imaging device 102 and the observation target as shown in the first and second embodiments. Therefore, among the distance to the observation object based on the distances d2, d3, d4, and d5 and the angle between the imaging surface of the imaging device 102 and the observation object, the angle in the height direction and the width direction of the captured image The vertical and horizontal tilt angles corresponding to can be calculated.

  More specifically, the directly-facing scale width calculation unit 193 determines the distances d2, d3, and the combination of the light spots B ′ and C ′ and the light spots D ′ and E ′ as a combination of two predetermined light spots. A scale scale that is a measure of the size of the observation object in the captured image at a distance from the tip of the imaging device 102 corresponding to any one of the maximum value, the minimum value, and the average value among d4 and d5 Calculate the width.

  Further, the tilt angle calculation unit 194 uses the combination of the light spots B ′ and C ′ and the light spots D ′ and E ′ as a combination of two predetermined light spots based on the intervals d2, d3, d4, and d5. Calculate the vertical and horizontal tilt angles. Similar to the tilt angle calculation unit 184 of the imaging apparatus 101 of the second embodiment, the horizontal tilt angle can be calculated based on the distances d2 and d3 corresponding to the light spots B ′ and C ′, and the light spots D ′ and E are calculated. The vertical tilt angle can be calculated based on the intervals d4 and d5 corresponding to '. Since the calculation principle is the same as that of the tilt angle calculation unit 184 of the second embodiment, it is omitted here.

  As a result, the scale width correction unit 195 can perform the tilt correction on the scale width calculated by the directly-facing scale width calculation unit 193 based on the vertical tilt angle and the horizontal tilt angle.

  FIG. 18 is an image diagram of a captured image drawn with scales drawn by the scale drawing unit 160, and illustrates the case where a crack on the observation object is inspected using the imaging device 102.

  As shown in FIG. 18, by drawing a scale on the captured image, it is possible to measure the size of the crack using the scale as a scale. In the present embodiment, the scale in consideration of the vertical tilt angle in addition to the horizontal tilt angle is compared with the image diagram of the captured image in which the scale is drawn by the imaging apparatus 101 of the second embodiment shown in FIG. Since it is drawn, the size of the crack in the height direction in the captured image can be measured more accurately than the imaging device 101 of the second embodiment.

  Also, as shown in FIG. 18, by drawing the calculated distance between the tip of the imaging device 102 and the observation target on the captured image, the user of the imaging device 102 can determine the distance to the observation target. The size of the crack on the observation object can be easily known.

  In FIG. 18, the scale shape is drawn as a cross scale, but the present invention is not limited to this, and may be a grid scale, for example. Further, a scale that has been corrected in consideration of distortion by the optical system of the imaging unit 120 may be drawn.

  Note that the above example is merely an example, and the geometric relationship changes depending on the arrangement of the imaging unit 120 and the laser light sources 110, 111, 112, and 113 in the imaging apparatus 102, and the position of the reference point. Change. However, in the calculation formula, the value changes according to the positional relationship between the imaging surface of the imaging device 102 and the observation object only in the interval between the four light spots and the reference point, and is necessary for other calculations. Since these parameters are device-specific values, the tilt angle can be calculated if the distances between the four light spots and the reference point are known, as in the above example.

Next, the effect of the present embodiment will be described.
As described above, in this embodiment, in addition to the effects of the first and second embodiments, when the observation target and the imaging device 103 are not facing each other, based on the intervals d2 and d3 and the intervals d4 and d5. The vertical tilt angle and the horizontal tilt angle can be calculated, and a scale in consideration of the vertical tilt angle and the horizontal tilt angle can be drawn on the captured image.

  In addition, an expensive laser distance meter is not required for a significant cost reduction of the imaging apparatus, and thus the same effect as that of the second embodiment can be obtained. Furthermore, compared to the imaging apparatus 101 of the second embodiment, in this embodiment, the scale is drawn in consideration of two tilt angles, so that the size of the observation object can be measured more accurately. it can.

  Note that the imaging devices 100, 101, and 102 of the first, second, and third embodiments described above are examples, and the configuration and operation thereof can be changed as appropriate without departing from the spirit of the invention. For example, in the first embodiment described above, one laser light source is provided in the second embodiment, and two laser light sources are provided in the third embodiment. However, more laser light sources may be provided. This makes it possible to calculate distances and the like using the intervals between a plurality of light spots, so that the calculation accuracy can be improved.

  In addition to the functions realized by the dedicated hardware as described above, the functions of the imaging devices 100, 101, and 102 of the present invention are stored in the imaging devices 100, 101, and 102 with programs for realizing the functions. The program may be recorded on a readable recording medium, the program recorded on the recording medium is read by the imaging apparatuses 100, 101, and 102, and executed by a computer. Recording media readable by the imaging devices 100, 101, 102 include recording media such as floppy (registered trademark) disks, magneto-optical disks, CD-ROMs, and hard disk devices incorporated in the imaging devices 100, 101, 102, etc. Refers to a storage device. Further, the recording media that can be read by the imaging devices 100, 101, 102 include those that dynamically hold a program for a certain period of time, such as a volatile memory inside the imaging devices 100, 101, 102.

100, 101, 102 Imaging device 110, 111, 112, 113 Laser light source 120 Imaging unit 130 Light spot detection unit 140, 180, 190 Scale generation unit 141, 181, 191 Reference point interval calculation unit 142, 182, 192 Scale width calculation Units 183 and 193 Face-to-face scale width calculation units 184 and 194 Angle angle calculation units 185 and 195 Scale width correction units 186 and 196 Matrix calculation units 187 and 197 Projection correction unit 150 Distance calculation unit 160 Scale drawing unit 170 Display units 200 and 201 Laser beam 300 Observation target

Claims (10)

An imaging unit for capturing an observation object as a captured image;
Two or more laser light sources fixed so as to irradiate laser light in parallel with the imaging direction of the imaging unit and to be arranged around the imaging object at an equal distance from the center of the imaging unit;
A light spot detection section for calculating said superimposed on the observed object on the photographed image to detect two or more light spots produced, the position on the captured image of the light spot by reflection of the laser light,
A reference point interval calculation unit that calculates an interval between the light spot and the center of the captured image based on positions of the two or more light spots on the captured image;
Of the two or more light spots detected by the light spot detection section, the reference point interval calculation section calculates the predetermined two light spots arranged on the same straight line passing through the center of the captured image. Based on the measured interval , the size of the observation object in the captured image at a distance from the tip of the imaging device corresponding to any one of the maximum value, the minimum value, and the average value of the interval The scale width of the scale serving as a measure of the scale, the correspondence between the distance between the position of the intersection and the center of the captured image, and the distance between the observation object and the tip of the imaging device A facing scale width calculation unit that calculates using distance calibration data indicating the relationship,
Of the angles formed by the imaging surface of the imaging device and the observation object based on the interval, the angle in the height direction or the width direction in the captured image is calculated as a vertical or horizontal tilt angle, respectively. And
The vertical tilt angle calculated by the tilt angle calculation unit or the vertical tilt angle calculated by the tilt angle calculation unit in order to perform tilt correction on the scale width calculated by the directly-facing scale width calculation unit based on the vertical tilt angle or the horizontal tilt angle. A matrix calculation unit that calculates a projective transformation matrix that performs projective transformation of the scale based on a lateral tilt angle, and a projection correction unit that corrects the scale width calculated by the directly-facing scale width calculation unit based on the projective transformation matrix A scale width correction unit comprising :
A scale drawing unit for drawing the scale on the captured image based on the scale width calculated by the scale width correction unit;
An imaging apparatus comprising: the captured image that has not been subjected to image distortion correction; and a display unit that displays the scale drawn on the captured image. The imaging apparatus according to claim 1,
At least one has at least four laser light sources that are not collinear;
The scale width calculator is
Among the four or more light spots detected by the light spot detection unit, the reference point with respect to two predetermined light spots that are on the same straight line and orthogonal to each other at the center of the captured image Based on the interval calculated by the interval calculation unit, the observation in the captured image at a distance from the tip of the imaging device corresponding to any one of the maximum value, the minimum value, and the average value of the interval A directly-facing scale width calculator that calculates the scale width of the scale, which is a measure of the size of the object,
Of the angles formed by the imaging surface of the imaging apparatus and the object to be observed based on the interval, the angle in the height direction and the width direction in the captured image is calculated as a vertical tilt angle and a horizontal tilt angle, respectively. And
The vertical tilt angle calculated by the tilt angle calculation unit and the vertical tilt angle calculated by the tilt angle calculation unit in order to correct the tilt width calculated by the directly-facing scale width calculation unit based on the vertical tilt angle and the horizontal tilt angle. A matrix calculation unit that calculates a projective transformation matrix that performs projective transformation of the scale based on a lateral tilt angle, and a projection correction unit that corrects the scale width calculated by the directly-facing scale width calculation unit based on the projective transformation matrix An imaging apparatus having a scale width correction unit comprising: The imaging apparatus according to claim 1 or 2 ,
A distance calculator that calculates a distance between the tip of the imaging device and the observation object based on the interval calculated by the reference point interval calculator;
The scale drawing unit draws the distance calculated by the distance calculation unit at a predetermined position on the captured image in addition to the scale and draws it on the captured image. A method for generating the scale of an imaging apparatus, which captures an observation object as a captured image, and displays a scale that is a measure of the size of the observation object drawn on the captured image and the captured image. ,
Irradiating a laser beam parallel to the imaging direction of the imaging unit, and, two or more laser light sources which are fixed to place around the imaging object equidistant from the center of the imaging unit, the laser An irradiation step of irradiating light;
A light spot detecting step of detecting at least two light spots caused superimposed on the observed object on the captured image by reflection of the laser beam, calculates the position on the captured image of the light spot,
A reference point interval calculating step for calculating an interval between the light spot and the center of the captured image based on positions of the two or more light spots on the captured image;
Among the two or more light spots detected in the light spot detection step, calculation is performed in the reference point interval calculation step for two predetermined light spots arranged on the same straight line passing through the center of the captured image. Based on the measured interval , the size of the observation object in the captured image at a distance from the tip of the imaging device corresponding to any one of the maximum value, the minimum value, and the average value of the interval The scale width of the scale serving as a measure of the scale, the correspondence between the distance between the position of the intersection and the center of the captured image, and the distance between the observation object and the tip of the imaging device A straight scale width calculation step to calculate using the distance calibration data indicating the relationship;
Of the angles formed by the imaging surface of the imaging device and the observation object based on the interval, the angle in the height direction or the width direction in the captured image is calculated as a vertical or horizontal tilt angle, respectively. Steps ,
The vertical tilt angle calculated by the tilt angle calculation unit or the vertical tilt angle calculated in the tilt angle calculation unit in order to perform tilt correction on the scale width calculated in the facing scale width calculation step based on the vertical tilt angle or the horizontal tilt angle. A matrix calculation step for calculating a projection transformation matrix for projective transformation of the scale based on a lateral tilt angle, and a projection correction step for correcting the scale width calculated by the facing scale width calculation unit based on the projection transformation matrix; A scale width correction step consisting of:
A scale generation step comprising: a scale drawing step for drawing the scale in a superimposed manner on the captured image that has not been subjected to image distortion correction based on the scale width calculated in the scale width correction step. Method. It is the scale production | generation method of Claim 4 , Comprising:
At least one has at least four laser light sources that are not collinear;
The scale width calculating step includes:
Among the four or more light spots detected in the light spot detection step, the reference point with respect to two predetermined light spots that are on the same straight line and orthogonal to each other at the center of the captured image Based on the interval calculated in the interval calculation step, the observation in the captured image at a distance from the tip of the imaging device corresponding to any one of the maximum value, the minimum value, and the average value of the interval A straight scale width calculation step for calculating a scale width of the scale which is a measure of the size of the object;
Of the angles formed by the imaging surface of the imaging apparatus and the object to be observed based on the interval, the angle in the height direction and the width direction in the captured image is calculated as a vertical tilt angle and a horizontal tilt angle, respectively. Steps,
The vertical tilt angle calculated by the tilt angle calculation unit and the vertical tilt angle calculated by the tilt angle calculation unit to correct the tilt width calculated in the directly-facing scale width calculation step based on the vertical tilt angle and the horizontal tilt angle. A matrix calculation step for calculating a projection transformation matrix for projective transformation of the scale based on a lateral tilt angle, and a projection correction step for correcting the scale width calculated by the facing scale width calculation unit based on the projection transformation matrix; A scale generation method comprising a scale width correction step. A scale generation method according to claim 4 or 5 ,
A distance calculation step of calculating a distance between the tip of the imaging device and the observation object based on the interval calculated in the reference point interval calculation step;
The scale drawing step is a scale generation method in which, in addition to the scale, the distance calculated in the distance calculation step is drawn at a predetermined position on the captured image so as to overlap the captured image. Irradiates laser light in parallel with the imaging direction, and includes two or more laser light sources fixed so as to be arranged around the imaging object at an equal distance from the center of the imaging unit, and images an observation object A scale generation program for capturing an image as an image and drawing the scale on an imaging device that displays the captured image and a scale serving as a scale of the size of the observation object drawn on the captured image.
A light spot detecting step of detecting two or more light spots generated superimposed on the observed object on the captured image by reflection of the laser light,
A light spot position calculation procedure for calculating the position of the light spot detected in the light spot detection procedure on the captured image;
A reference point interval calculation procedure for calculating an interval between the light spot and the center of the captured image based on the position of the light spot calculated in the light spot position calculation procedure;
Two or more light beams irradiated with laser light from at least two of the laser light sources and subjected to detection and position calculation on the captured image in the light spot detection procedure and the light spot position calculation procedure, respectively. Based on the interval calculated in the reference point interval calculation procedure for two predetermined light spots arranged on the same straight line passing through the center of the captured image among the points, the maximum value and minimum value of the interval A scale width of a scale that is a measure of the size of the observation object in the captured image at a distance from the tip of the imaging device corresponding to any of the value and the average value thereof , geometrically, Alternatively, a straight scale that is calculated using distance calibration data indicating the correspondence between the distance between the position of the intersection and the center of the captured image and the distance between the observation object and the tip of the imaging device. Width calculation procedure,
Of the angles formed by the imaging surface of the imaging device and the observation object based on the interval, the angle in the height direction or the width direction in the captured image is calculated as a vertical or horizontal tilt angle, respectively. Procedure and
The vertical tilt angle calculated by the tilt angle calculation unit or the vertical tilt angle calculated by the tilt angle calculation unit in order to perform tilt correction on the scale width calculated by the straight scale width calculation procedure based on the vertical tilt angle or the horizontal tilt angle. Matrix calculation procedure for calculating a projection transformation matrix for projective transformation of the scale based on a lateral tilt angle, and a projection correction procedure for correcting the scale width calculated by the facing scale width calculation unit based on the projection transformation matrix A scale width correction procedure consisting of :
Based on the scale width calculated in the scale width correction procedure, the imaging apparatus causes the imaging apparatus to execute a scale drawing procedure for drawing the scale on the captured image that has not been subjected to image distortion correction. Scale generation program for. A scale generation program according to claim 7 ,
The scale width calculation procedure is as follows:
At least one is irradiated with laser light from at least four laser light sources that are not located on the same straight line, and is detected and calculated in the light spot position calculation procedure and the position on the captured image, respectively. Among the four or more light spots that have been subjected to the calculation, calculation is performed with the reference point interval calculation procedure for two predetermined light spots that exist on the same straight line that are orthogonal to each other at the center of the captured image. Based on the measured interval, the size of the observation object in the captured image at a distance from the tip of the imaging device corresponding to any one of the maximum value, the minimum value, and the average value of the interval The straight scale width calculation procedure to calculate the scale width of the scale that is the scale of
Of the angles formed by the imaging surface of the imaging apparatus and the object to be observed based on the interval, the angle in the height direction and the width direction in the captured image is calculated as a vertical tilt angle and a horizontal tilt angle, respectively. Procedure and
The vertical tilt angle calculated by the tilt angle calculation unit and the vertical tilt angle calculated by the tilt angle calculation unit to correct the tilt width calculated by the straight scale width calculation procedure based on the vertical tilt angle and the horizontal tilt angle. Matrix calculation procedure for calculating a projection transformation matrix for projective transformation of the scale based on a lateral tilt angle, and a projection correction procedure for correcting the scale width calculated by the facing scale width calculation unit based on the projection transformation matrix A scale generation program having a scale width correction procedure comprising: A scale generation program according to claim 7 or 8 ,
A distance calculation procedure for calculating a distance between the tip of the imaging device and the observation object based on the interval calculated in the reference point interval calculation procedure;
The scale drawing procedure is a scale generation program that draws the distance calculated by the distance calculation procedure at a predetermined position on the captured image in addition to the scale so as to be superimposed on the captured image. A computer-readable recording medium on which the program according to claim 7 is recorded.

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