JP6205465B2 - Shallow water observation system - Google Patents

Description

  The present invention relates to a shallow water observation system for acquiring and processing image information of a bottom of a lake or a shallow water area in a coastal area, for example, a shallow water area centered on a coral reef.

  Shallow water ecosystems such as coral reefs are regarded as important environmental indicators that reflect changes in the global environment.

  As an observation method of an ecosystem in a shallow water area, for example, Japanese Patent Laid-Open No. 2003-4845 (Patent Document 1) discloses an observation method using an acoustic sounding instrument that supports the water surface so as to be able to travel (Patent Document 1). According to such an observation method, it is possible to obtain map information such as a wide range of seabed topography by water depth observation.

  Japanese Patent No. 4173027 (Patent Document 2) discloses an observation method using a video camera supported by towing so as to be movable underwater (see FIG. 1 of Patent Document 2). It is possible to observe images over a wide range.

JP 2003-4845 A Japanese Patent No. 4173027

  However, the information obtained when observing with an acoustic sounding device is limited to water depth information by ultrasonic reflection such as a fish finder, single beam, narrow multi-beam, etc., so it relates to optical properties such as colors including the visible light range. There is a problem that information cannot be reflected.

  On the other hand, underwater images obtained with a video camera can grasp the optical properties by dynamic observation in water, but it is transient image information and does not have geographical coordinates. There was a problem that it could not be the basis of quantitative analysis covering general characteristics.

Accordingly, an object of the present invention is to provide a shallow water observation system that enables quantitative analysis over the entire optical properties of a wide range of water bottom modes by using information on the bottom of the shallow water .

This object of the present invention is to
A moving support floating body that supports the observation equipment so that it can move on the water;
A pair of underwater cameras for detecting visible light mounted on the movable supporting floating body;
A distance measuring device capable of measuring the distance to the bottom of the water,
A posture / GPS sensor for detecting postures of the plurality of underwater cameras and detecting shooting positions of the pair of underwater cameras;
Further, a recording means for recording synchronized with attitude and imaging position of the pair of the pair of underwater camera detected by the images taken the posture / GPS sensor by underwater camera,
An image processing unit for processing a recorded image of the recording means;
A shallow seafloor observation system comprising a distance data processing unit for processing distance data generated by the distance measuring device,
The image processing unit can generate DSM data to which geographical coordinates are given by image processing based on respective imaging conditions for an overlapping range of a plurality of captured images captured by the underwater camera,
The distance data processing unit uses the attitude data measured by the attitude / GPS sensor, the distance data processing unit converts the distance data generated by the distance measuring device into water depth data, and converts the data into the water depth data. Based on this, it is possible to generate complementary DSM data,
The image processing unit supplements the DSM data with the supplemental DSM data generated by the distance data processing unit when a part of the bottom surface data obtained by the pair of underwater cameras is missing. The shallow water area is configured to generate DSM data of the shallow sea bottom region to be imaged and to create an orthographic projection photograph based on the obtained DSM data of the shallow sea bottom area Achieved by observation system.

  In this specification, DSM is an abbreviation for Digital Surface Model and refers to a numerical surface model.

  According to the present invention, the movable support floating body supports the observation equipment so as to be movable on the water, the underwater camera is supported by the movable support floating body, photographs the bottom of the water, and the photographing condition detection member detects the photographing condition of the underwater camera, The captured image and the shooting conditions are recorded synchronously by the recording member, and the image processing unit executes image processing of the captured image data. The overlapping range of a plurality of captured images by the underwater camera is corrected based on each shooting condition. By performing an orthogonal projection process, an orthographic projection image is output, and this orthographic projection image enables quantitative analysis over the entire optical properties of a wide range of water bottom aspects, and is also obtained by a similar contrast observation later. It becomes possible to quantitatively grasp the temporal change due to comparison with the orthographic projection image in the same range.

Furthermore, according to the present invention, the shallow water observation system includes a distance measuring device capable of measuring the distance to the bottom of the water in addition to the plurality of underwater cameras that detect visible light, so the water quality is contaminated. Therefore, when the underwater camera that detects visible light cannot accurately create the bottom surface data, and some of the bottom surface data obtained by the underwater camera that detects visible light is missing, When the bottom of the water is photographed by an underwater camera that detects visible light, the bottom surface data cannot be created with high accuracy, and one of the bottom surface data obtained by the underwater camera that detects visible light. If the area is missing, the sun will be shaded, at dawn / dusk, or the contrast will be very high. If a part of the bottom surface data is missing, the bottom surface image data obtained by video cameras placed on the left and right cannot be combined well (image matching processing), and a part of the bottom surface data is lost. Even if it is missing, the distance to the bottom of the water can be measured with a distance measuring device using laser, ultrasonic waves, etc., and it is possible to compensate for the lack of bottom surface data obtained by an underwater camera that detects visible light. Become.

  In a preferred embodiment of the present invention, the distance measuring device is constituted by a laser distance measuring device capable of measuring a distance to the water bottom using a laser.

  In a further preferred aspect of the present invention, the laser distance measuring device is attached to the lower surface of the movable support floating body.

  In a further preferred embodiment of the present invention, the plurality of underwater cameras for detecting visible light are arranged on the left and right outer sides or one of the movable support floating bodies.

  According to this preferred embodiment of the present invention, left and right or front and rear parallax images can be recorded by disposing the underwater cameras on the left and right outer sides of the movable support floating body or on one of them.

  In a further preferred embodiment of the present invention, the movable supporting floating body is constituted by a floating body dedicated to the observation equipment.

ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the shallow water area observation system which enables the quantitative analysis covering the whole optical property of a wide water bottom aspect with the water bottom information of a shallow water area .

  In addition, according to the present invention, since the water quality is contaminated, the underwater camera that detects visible light cannot accurately create the water bottom surface data, and is obtained by the underwater camera that detects visible light. When a part of the water bottom surface data is missing or when the water bottom is photographed by an underwater camera that detects visible light, it becomes shaded and the water bottom surface data cannot be created accurately and is visible. If part of the bottom surface data obtained by an underwater camera that detects light is missing, the exposure will be insufficient due to the lack of brightness due to the extremely high contrast due to the shade of the sun or at dawn / dusk. If there is a part that cannot be obtained, and a part of the bottom surface data is missing, further, the bottom surface image obtained by video cameras placed on the left and right Even if the image matching process is not successful and some of the bottom surface data is missing, the bottom surface data obtained by the underwater camera that detects the visible light by measuring the distance to the bottom with a ranging device. It becomes possible to compensate for deficiencies.

FIG. 1 is a functional configuration diagram of a shallow water observation system according to a preferred embodiment of the present invention. FIG. 2 is a block diagram showing components of the shallow water observation system according to the preferred embodiment of the present invention shown in FIG. FIG. 3 is a schematic perspective view of a laser beam emitting portion of the laser distance measuring device. FIG. 4 is a schematic perspective view of a laser beam receiving unit of the laser distance measuring device. FIG. 5 is a schematic longitudinal sectional view of the light receiving sensor 47. FIG. 6 is a block diagram of a control system and a detection system of the laser distance measuring apparatus. FIG. 7 is a flowchart showing a process of observing the shallow seabed by the shallow water area observation system according to the preferred embodiment of the present invention shown in FIGS. 1 to 6.

FIG. 1 is a functional configuration diagram of a shallow water observation system according to a preferred embodiment of the present invention.

As shown in FIG. 1, a shallow water area observation system 1 according to a preferred embodiment of the present invention includes a moving support floating body 2 that supports and supports observation equipment so as to be movable on the water, and a water support image that is supported by the moving support floating body 2. Shooting with a pair of video cameras 3 and 3 capable of underwater shooting, a laser distance measuring device 8 attached to the lower surface of the movable support floating body 2 and scanning the sea bottom with a laser beam, and a pair of video cameras 3 and 3 A GPS / gyro device (posture measuring device) 4 that is a photographing condition detection member that detects a position and a posture at the time of photographing, and a water bottom image photographed by a pair of video cameras 3 and 3 and a specified photographing condition are synchronized. Based on the recording unit 5 composed of a video recorder for recording and the bottom image and photographing conditions recorded in the recording unit 5, the bottom image is processed in real time on the moving support floating body 2. Alternatively, a personal computer 7 having an image processing unit 6 to the image processing underwater image after shooting the end of work.

  In this embodiment, the movable supporting floating body 2 supports a dedicated or general-purpose floating body such as an outrigger type small boat, an inflatable boat, a fishing boat, etc., a pair of video cameras 3 and 3, and a GPS / gyro device (attitude measurement device) 4. And a dedicated support that is a gantry that can be widely applied in shallow water and enables stable photographing. The moving support floating body 2 is moved on the water along the planned shooting process line by towing or self-propelled, and water bottom observation is performed.

  As each video camera 3, a video camera capable of underwater photography provided with a high-speed shutter that is housed in a housing and can be electronically controlled is used. As the video camera 3, it is possible to shoot 80% of the water bottom images at close distances of less than 10 m, and to record a clear image with a high-speed shutter even when it is shaken by waves. It is used and supported by the moving support floating body 2 for moving in the shallow sea area.

  In FIG. 1, what is indicated by reference numerals 52 and 52 is an imaging region of the sea bottom imaged by a pair of video cameras 3 and 3. As shown in FIG. The three shooting areas 52 and 52 overlap in the overlap area 53.

  The pair of video cameras 3 and 3 are disposed on both the left and right sides of the movable support floating body 2.

  The GPS / gyro apparatus (attitude measurement apparatus) 4 is configured to detect the position of the video cameras 3 and 3 and the attitude data of the video cameras 3 and 3 in the optical axis direction and apply high-precision DGPS.

  The recording unit (video recorder) 5 records the water bottom image photographed by the video cameras 3 and 3 and the photographing conditions in a recording medium in synchronism, and records this on the image of the personal computer 7 mounted on the movable support floating body. It can be input to the processing unit 6 or input to the image processing unit 6 of the personal computer 7 located on the ground by portable media or wireless transmission.

  The image processing unit 6 is input with the seafloor video data generated by the pair of video cameras 3, 3, attitude data of the pair of video cameras 3, 3, and position data of the pair of video cameras 3, 3 for image processing. The unit 6 is configured to create a DSM model, which is a numerical ground model represented on geographic coordinates, by stereo matching based on these data.

FIG. 2 is a block diagram of a DSM creation unit and an orthographic photograph creation unit in the shallow water observation system 1 according to the preferred embodiment of the present invention shown in FIG.

As shown in FIG. 2, the shallow water observation system 20 includes a personal computer 30, a synchronization signal generator 31, a pair of video cameras 3 and 3, video recorders 33 and 33, and video editors 34 and 34. , A GPS / gyro device 4 and a laser distance measuring device 8 are provided.

As shown in FIG. 2, the shallow water observation system 20 further includes a DSM data generation unit 11 that generates DSM data, and an orthographic photograph generation unit 12 based on the DSM data.

  FIG. 3 is a schematic perspective view of the laser beam emitting portion of the laser distance measuring device 8.

  As shown in FIG. 3, the laser distance measuring device 8 includes an LED laser light source 41 that emits a laser beam 40 in a pulse shape, and the laser beam 40 emitted from the LED laser light source 41 is incident on a collimator lens 42. And converted into a parallel beam. The laser beam 40 converted into a parallel beam by the collimator lens 42 enters the diffusing member 43, and the diffusing member 43 divides the laser beam 40 into a plurality of laser beams 45, for example, in a 128 × 128 matrix form. Irradiates the bottom of the sea.

  As the diffusing member 43, for example, a diffusing member used in “3D Flash Lidar” (registered trademark) manufactured and sold by Advanced Scientific Concepts, Inc. is preferably used.

  FIG. 4 is a schematic perspective view of a laser beam receiving unit of the laser distance measuring device 8.

  As shown in FIG. 4, the laser beam 45 divided by the diffusing member 43 and reflected by the sea bottom is collected by the condenser lens 46 and is photoelectrically detected by the light receiving sensor 47.

  FIG. 5 is a schematic longitudinal sectional view of the light receiving sensor 47. As shown in FIG. 5, the light receiving sensor 47 includes a photo sensor 48 that senses the detection time of the laser beam 45 reflected by the sea bottom and a sea bottom. A CCD sensor 49 for detecting the intensity of the reflected laser beam 45 is provided.

  FIG. 6 is a block diagram of a control system and a detection system of the laser distance measuring device 8.

  As shown in FIG. 6, the laser distance measuring device 8 has a time when a laser beam 40 is emitted in a pulse form from a laser light source 41 and a laser beam 45 generated by reflecting the laser beam 40 by the sea bottom. A first memory 50A for storing the time received by the photosensor 48, and a second memory area for storing the intensity of the laser beam 40 emitted from the laser light source 41 and the intensity of the laser beam 45 detected by the CCD sensor 49. It has a RAM 50 with 50B.

  Further, the laser distance measuring device 8 includes the time when the laser beam 40 is emitted from the laser light source 41 stored in the first memory 50A of the RAM 50, the time received by the photosensor 48, and the laser beam reflected by the seabed. And a controller 51 for calculating a distance to the sea bottom based on the time when the photosensor 48 receives 45, the intensity of the laser beam 40 emitted from the laser light source 41, and the intensity of the laser beam 45 detected by the CCD sensor 49. ing.

  As shown in FIG. 6, the laser distance measuring device 8 includes a laser data processing unit 10 that processes data obtained by irradiation with the laser beam 40.

  When the laser beam 40 is divided by the diffusing member 43 and irradiated to the sea bottom in a 128 × 128 matrix, the laser beam 45 reflected by the elements of the 128 × 128 matrix is converted into the photo sensor 48 and the CCD sensor. By performing photoelectric detection by 49, the distance between the element and the laser light source 41 can be accurately calculated. Therefore, the distance between all the elements of the 128 × 128 matrix and the laser light source 41 can be accurately calculated. Is possible.

FIG. 7 is a flowchart showing processing for observing the shallow seabed by the shallow water observation system 2 according to the preferred embodiment of the present invention shown in FIGS. 1 to 6.

  When a start signal is input to the personal computer 30 by an operator, a drive signal is output from the personal computer 30 to the synchronization signal time code generator 31, and the pair of video cameras 3, 3 is output from the synchronization signal time code generator 31. Then, a synchronization signal is output to the laser distance measuring device 8, the GPS / gyro device 4, and the conversion software 55. At this time, the personal computer 30 stores the time when the laser beam 40 is emitted from the laser light source 41 in the first memory area 50 </ b> A in the RAM 50 of the laser distance measuring device 8 and the laser beam emitted from the laser light source 41. The intensity of 40 is stored in the second memory area 50B in the RAM 50 of the laser distance measuring device 8.

  When the synchronization signal is received, the pair of video cameras 3 and 3 start photographing, and color images of the photographing areas 52 and 52 on the sea bottom are photographed.

  On the other hand, the laser distance measuring device 8 emits the laser beam 40 in a pulse form from the laser light source 41, converts the laser beam 40 into a parallel beam by the collimator lens 42, and then makes it incident on the diffusing member 43. By passing through the diffusing member 43, the laser beam 40 is divided into a number of laser beams 45, for example, 128 × 128, and the imaging areas 52, 52 on the bottom surface of the pair of video cameras 3, 3 overlap. The overlapping imaging region 53 is irradiated, and a 128 × 128 matrix irradiation unit 53 </ b> A is formed in the overlapping imaging region 53.

  The laser beam 45 reflected by each of the 128 × 128 matrix irradiation portions 53A on the sea bottom is condensed by the condensing lens 46 and is photoelectrically detected by the light receiving sensor 47.

  As described above, the light receiving sensor 47 includes the photo sensor 48 that senses the detection time of the laser beam 45 reflected by the sea bottom and the CCD sensor 49 that detects the intensity of the laser beam 45 reflected by the sea bottom. ing.

  When the photosensor 48 detects the laser beam 45 reflected by each of the 128 × 128 matrix-shaped irradiation portions 53A on the sea bottom, the time when the laser beam 45 is detected is stored in the first memory area 50A in the RAM 50. To store. Here, the first memory area 50A is divided into 128 × 128 matrix memory areas corresponding to the 128 × 128 matrix irradiation unit 53A, and the photosensor 48 is 128 × 128 on the sea bottom. The detection time of the laser beam 45 reflected by each of the matrix irradiation units 53A is stored in the corresponding matrix memory area in the first memory area 50A.

  On the other hand, the CCD sensor 49 detects the intensity of the laser beam 45 reflected by each of the 128 × 128 matrix irradiation units 53A on the sea bottom and reflects by each of the 128 × 128 matrix irradiation units 53A on the sea bottom. The intensity of the laser beam 45 is stored in a corresponding matrix memory area in the second memory area 50B.

  Next, the controller 51 accesses the RAM 50, the time when the laser beam 40 is emitted from the laser light source 41 stored in each of the matrix memory areas in the first memory area 50 </ b> A, and the laser beam 45 by the photo sensor 48. The detected time and the intensity of the laser beam 40 emitted from the laser light source 41 stored in each of the matrix memory areas in the second memory area 50B and the intensity of the laser beam 45 detected by the CCD sensor 49 are shown. Based on the read out data, the water depth data of the 128 × 128 matrix irradiation unit 53A on the sea bottom is calculated.

  In response to the synchronization signal, the GPS / gyro device 4 generates attitude data of the pair of video cameras 3 and 3, the conversion software is activated, and an external rating element in the photogrammetry is calculated.

  In response to the synchronization signal, the image data corresponding to the image of the sea bottom photographed by the pair of video cameras 3 and 3 is output to the video recorders 33 and 33, and further, the video editors 34 and 34 sequentially output the serial number images. Is generated. Next, the focal length and lens distortion are corrected using separately observed camera parameters, and corrected serial images (pair images every 1/30 seconds) are generated.

  Here, the camera parameters are observed by photographing a target separately installed in the aquarium with the underwater video camera 3 and obtaining a focal length and lens distortion using a photogrammetry formula.

  For example, template matching is performed on the left and right images having the same sequence number from the sequence-corrected sequence images generated from the images captured by the pair of video cameras 3 and 3 to calculate the lateral parallax. The water depth data is calculated from the lateral parallax thus obtained, and the altitude value A (x, y, z) is calculated based on the water depth data.

  Next, the lateral parallax is removed from the distortion-corrected serial number images obtained by either the left or right of the pair of video cameras 3 and 3 using the posture data measured by the GPS / gyro device 4.

  For example, template matching is performed on the corrected sequential image (vertical = time axis) from which the horizontal parallax has been removed to calculate the vertical parallax.

  Using the vertical parallax thus obtained, the altitude value is calculated, the water depth data is calculated, and the altitude value B (x, y, z) is calculated based on the water depth data.

  In this way, the elevation value A (x, y, z) and the elevation value B (x, y, z) are calculated, and the elevation value A (x, y, z) and elevation value B (x, y, z) are calculated. DSM data is created using the altitude value obtained by synthesizing.

  On the other hand, the distance data generated by the laser distance measuring device 8 is converted into water depth data by the laser data processing unit 10 using the attitude data measured by the GPS / gyro device 4, and this water depth data is also stored. And DSM data of elevation values for complementation are generated.

  Here, the water depth data generated by the laser distance measuring device 8 is, for example, the water depth data of a 128 × 128 matrix region 53A, and further, the overlapping photographing region 53 is further divided to form a 256 × 256 matrix. Even if the region 53A is generated and the water depth data is obtained, the size of each region 53A is much larger than the pixels of the image captured by the pair of video cameras 3 and 3, and therefore in this embodiment, Based on the water depth data of the matrix-like region 53A generated by the laser distance measuring device 8, complementary DSM data for complementing the DSM data generated by the images photographed by the pair of video cameras 3 and 3 is generated. The

  Thus, the DSM data of the seabed region to be imaged is generated by the DSM data generated based on the images captured by the pair of video cameras 3 and 3 and the complementary DSM data generated by the laser distance measuring device 8. . Here, the complementary DSM data generated by the laser distance measuring device 8 is not applied to the seabed area where the DSM data normally generated from the images taken by the pair of video cameras 3 and 3 is present.

  On the other hand, the corrected sequential image is projected superimposed on the DSM data.

  Next, the ortho image creation software is started, and the image thus obtained is orthographically projected using the external rating element generated by the conversion software, and orthographic projection photographic image data is created.

  In observation, while moving the moving support floating body 2 along the observation plan line by towing or self-propelled, the bottom image is taken by the pair of video cameras 3 and 3 as described above, and the bottom of the water is detected by the laser distance meter 8. , And the GPS / gyro device 4 detects the viewpoint position and the optical axis direction, which are the shooting conditions of the pair of video cameras 3 and 3, and the video recorders 33 and 33 record both of them synchronously. Is done.

  After the observation is finished, the orthographic photographic image data is input to the image processing unit 6 of the personal computer 7 mounted on the moving support floating body 2, or the personal computer located on the ground by portable media or wireless transmission. 7 is input to the image processing unit 6 to execute orthographic projection image processing.

  This image processing output can visually indicate the state of shallow water coral reefs and shallow waters by visually expressing the shallow water coral reefs and shallow waters indicated by conventional contour lines and symbols in color. .

  Therefore, according to this embodiment, since the underwater environment of the shallow reefs and shallows can be captured in color, it is possible to grasp the growth of coral reefs and shallow vegetation (algae) due to different colors. It becomes possible.

In addition, according to this embodiment, the shallow water observation system 20 includes the laser rangefinder 8 that can measure the distance to the bottom of the water in addition to the pair of video cameras that detect visible light, so that the water quality is contaminated. Therefore, depending on the video cameras 3 and 3 that detect visible light, the bottom surface data cannot be created with high accuracy, and the bottom surface data obtained by the video cameras 3 and 3 that detect visible light cannot be generated. When a part is missing or when the bottom of the water is photographed by the video cameras 3 and 3 that detect visible light, it becomes shaded and the bottom surface data cannot be created with high accuracy. If a part of the bottom surface data obtained by an underwater camera that detects light is missing, the contrast is extremely high due to the shade of the sun, dawn / dusk, or low brightness. When there is a part where sufficient exposure cannot be obtained and a part of the bottom surface data is missing, the bottom surface image obtained by the pair of video cameras 3 and 3 arranged on the left and right (image matching) The bottom of the water obtained by the video cameras 3 and 3 that detect the visible light by measuring the distance to the bottom of the water by the laser distance meter 8 even when a part of the bottom surface data is missing. It becomes possible to compensate for missing surface data.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the invention described in the claims, and these are also included in the scope of the present invention. Needless to say.

  For example, in the above embodiment, a pair of video cameras 3 and 3 are provided, but the number of video cameras is not limited to two as long as it is plural.

  In the above embodiment, the distance measuring device 8 that measures the distance to the bottom of the water is manufactured and sold by the diffusion member 43 that splits the laser beam 40 into a number of laser beams 45, preferably Advanced Scientific Concepts, Inc. However, it is not always necessary to use the laser distance measuring device 8 provided with this type of diffusing member 43. A fiber type laser distance measuring device or a scanning type is also necessary. A laser range finder, etc. can be used, and furthermore, not a laser, but may be used with other frequencies such as electromagnetic waves and ultrasonic waves, and any distance meter that can measure the distance to the seabed However, it is not particularly limited.

  Further, in the above embodiment, the reflection intensity of the laser beam is measured using the CCD sensor 49. However, it is not always necessary to measure the reflection intensity of the laser beam using the CCD sensor 49. The sensor 47 may be constituted only by the photosensor 48.

  In the above embodiment, the laser distance measuring device 8 is attached to the lower surface of the movable support floating body 2. However, it is not always necessary to attach the laser distance measuring device 8 to the lower surface of the movable support floating body 2. It may be attached to the upper surface of the floating body 2, that is, only the movable supporting floating body 2 can be attached so that the laser distance measuring device 8 is located on the water or in the water.

  In the above embodiment, the shallow seabed is observed. However, the present invention is not limited to the shallow seabed observation, and can be widely used for observing lakes and shallow coastal waters.

1 Shallow seafloor observation system 2 Mobile support floating body 3 Underwater camera (video camera)
4 GPS / Gyro device 5 Recording unit (video recorder)
6 Image processing unit 7 Personal computer 8 Laser distance measuring device 10 Laser data processing unit 11 DSM creation unit 12 Orthophoto map creation unit 30 Personal computer 31 Sync signal generation device 33 Video recorder 34 Video editor 40 Laser beam 41 Laser light source 42 Collimator lens 43 Diffusing member 45 Laser beam 46 Condensing lens 47 Light receiving sensor 48 Photo sensor 49 CCD sensor 50 RAM
50A First memory area 50B Second memory area 51 Controller 52 Shooting area 53 of a pair of video cameras Overlapping shooting area 53A Matrix area 55 Convert software

Claims (4)

A moving support floating body that supports the observation equipment so that it can move on the water;
A pair of underwater cameras for detecting visible light mounted on the movable supporting floating body;
A distance measuring device capable of measuring the distance to the bottom of the water,
A posture / GPS sensor for detecting postures of the plurality of underwater cameras and detecting shooting positions of the pair of underwater cameras;
Further, a recording means for recording synchronized with attitude and imaging position of the pair of the pair of underwater camera detected by the images taken the posture / GPS sensor by underwater camera,
An image processing unit for processing a recorded image of the recording means;
A shallow seafloor observation system comprising a distance data processing unit for processing distance data generated by the distance measuring device,
The image processing unit can generate DSM data to which geographical coordinates are given by image processing based on respective imaging conditions for an overlapping range of a plurality of captured images captured by the underwater camera,
The distance data processing unit uses the attitude data measured by the attitude / GPS sensor, the distance data processing unit converts the distance data generated by the distance measuring device into water depth data, and converts the data into the water depth data. Based on this, it is possible to generate complementary DSM data,
The image processing unit supplements the DSM data with the supplemental DSM data generated by the distance data processing unit when a part of the bottom surface data obtained by the pair of underwater cameras is missing. In this way, DSM data of the shallow seabed region to be imaged is generated, and an orthographic projection photograph can be created based on the obtained DSM data of the shallow seabed region. Observation system.   2. The shallow sea bottom observation system according to claim 1, wherein the distance measuring device is configured by a laser distance measuring device capable of measuring a distance to a water bottom using a laser.   The shallow seafloor observation system according to claim 2, wherein the laser distance measuring device is attached to a lower surface of the movable supporting floating body.   The shallow seafloor observation system according to any one of claims 1 to 3, wherein the plurality of underwater cameras that detect visible light are arranged on both the left and right outer sides of the movable supporting floating body or one of them. .