JP3783835B2 - Quantity measuring device for fish going up the fishway - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a measuring device that measures the quantity when fish such as sweetfish run up a fishway.
[0002]
[Prior art]
In river dams, etc., there is a fishway for the purpose of protecting the natural environment and maintaining aquatic organisms. From the standpoint of securing marine resources, the status of fish (mainly sweetfish) in the fishway is confirmed. In order to do this, a counting survey is being conducted. This investigation has been carried out by methods such as visual inspection and capture by a conventional person. As an example of the survey, according to a survey conducted in the Sagami River in Kanagawa Prefecture in 1997, as shown in Fig. 8, the run-up was concentrated on 4 days from mid-March to mid-June. Moreover, by hour, more than 70% went up between 16:00 and 18:00.
[0003]
[Problems to be solved by the invention]
In the case of sweetfish, ascending is temporarily and concentrated in this way, and counting the number of ascending visually requires a great deal of labor and patience. Therefore, there has been a strong demand for the development of a method for mechanically counting the number of run-ups. Therefore, an object of the present invention is to automatically measure the quantity of fish that run up the fishway.
[0004]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the invention of claim 1 is directed to a camera installed at a position where an image of a fish going up the fishway jumps over the weir from the side and a detection of the passage of the fish from the image captured by the camera. A detection object having means for extracting a target area and binarizing with a predetermined threshold after pre-processing the extracted image of the detection target area and having a size within a range in which the size of the extracted area is defined in advance wherein the means for detecting as a school of fish and means for outputting the counted count the detected school of fish, further comprising a.
[0005]
According to a second aspect of the present invention, there is provided a camera installed at a position where an image is captured from the side in a region where a fish traveling up a fishway jumps over a weir, a video recorder for recording an image captured by the camera, and a recording on the video recorder A reproduction device for reproducing the extracted image, means for extracting a detection target region through which the fish passes from the image reproduced by the reproduction device, and pre-processing the extracted image of the detection target region and then binary with a predetermined threshold value and means for detecting a detection object having a size in the range of size of the extracted area is defined in advance as well as as a school of fish, and means for outputting the counted count the detected school of fish, a It is characterized by that.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing a schematic configuration of the present invention. In the figure, reference numeral 1 denotes an ITV camera installed in a fishway portion, where fishes going up the fishway are imaged and the images are input to the video tape recorder 2 and recorded. The video tape 3 recorded locally is taken out and transported to the image processing apparatus 4. The conveyed video tape 3 is reproduced by a reproduction device (not shown), and the image signal is input to the image processing device 4. The image processing device 4 extracts a detection target region through which the fish passes from the reproduced image.
[0007]
Next, after pre-processing the image of the detection target area, the image is binarized with a predetermined threshold value, and a fish shadow is detected. The detected fish shadows are sequentially counted, and the counting results are displayed on the display 5 and recorded.
Further, instead of the video tape recorder 2, an image may be recorded / reproduced by an HD (hard disk) recorder, a VD (video disk) recorder, or the like.
In addition to the configuration described above, an image signal captured by the camera 1 can be directly input to the image processing apparatus 4. In this case, it is necessary to move the image processing apparatus 4 close to the camera 1 or connect the camera 1 and the image processing apparatus 4 with a communication line.
[0008]
FIG. 2 is a block diagram showing an internal configuration of a part of the image processing apparatus 4 of FIG. An image signal captured by the camera 1 is input to the processing region extraction unit 41. The processing area extraction unit 41 extracts an image in the area by designating the area through which the fish passes on the screen. FIG. 3 shows an example of processing area extraction. The white part in this processing area is a fish shadow. Reference numeral 61 denotes a weir. Next, the extracted image is sent to the local filter processing unit 42. The local filter processing unit 42 performs smoothing using a mask of n × n (where n >> fx, fy) size sufficiently larger than the assumed fish size (fx × fy). Next, the smoothed image is sent to the inter-image difference processing unit 43.
[0009]
The inter-image difference processing unit 43 performs difference processing between the processing region image subjected to the local filter processing and the processing region image before processing. Next, the processed region image subjected to the difference processing is sent to the binarization unit 44. In the binarization unit 44, focusing on the fact that fish that run up shines the abdomen and creates a bright region by creating a spire-like wave at the time of landing, binarize a region that is brighter than a predetermined value by the difference between images. Extracted and sent to the counting unit 45. The counting unit 45 determines that the extracted area is a fish size if it is an assumed size of the fish, counts the number, and sends it to the storage unit 46. The storage unit 46 sequentially stores the sent count values and displays the count values on the display 5.
[0010]
Next, when the fish to be counted is sweetfish, the behavior of sweetfish going up will be described with reference to FIGS. FIG. 4 shows the ayu's run-up operation as seen from the cross section of the fishway 62, and FIG. Ayu is one that jumps up and down the fishway platform, and the other is a group of people who tend to go up in groups. And the more the sweetfish that goes up, the more the sweetfish that jumps tend to increase.
[0011]
For this reason, the number of jumps that can be visually counted can be multiplied by a multiplier (for example, 5) to estimate the number of run-ups. In addition, when there is a small group of sweetfish at the time of run-up, it is preferred to go up inconspicuous places such as the shade or the edge of the waterway, and in the case of a large number, the waterway is used to go up where there is an empty channel There is a tendency to go up the average width.
[0012]
Next, the basic principle of sweetfish detection by image processing will be described. Ayu is considered to shine in silvery white when jumping on the doll platform. Therefore, there are moments that shine brighter than the surrounding water surface. In addition, since the sweetfish is very fast, there is a case where a normal ITV camera has 30 frames per second and jumps to the next frame that jumps out of the surface of the water. For this reason, it is necessary to pay attention to the splash when landing. Since this splash shines in white just like sweetfish, if a sweetfish candidate is detected using the feature and the photographing range is fixed in advance, a detected object having a certain size can be counted as sweetfish.
[0013]
The video conditions at this time are as follows: First, considering the behavioral characteristics of sweetfish, the edge of a water channel that tends to be shaded so that it can be detected even if a group of sweetfish is a small group or a large group (at the time of a small group) And the center of the waterway (at the time of a large group) will be taken. Accordingly, when the entire width of the fishway is large, a plurality of cameras 1 are provided as shown in FIG. FIG. 6A shows one camera 1 installed when the fishway width is about 2 m, and FIG. 6B shows two cameras 1 installed facing each other when the fishway width is 5 m or more. is there. FIG. 7 is a view of the arrangement of the camera 1 as seen from the side. In addition, in order to ensure a good image, it is necessary to avoid direct incidence of sunlight on the camera 1 or incidence after reflection on the water surface, and careful examination is necessary in consideration of installation conditions on site. .
[0014]
Therefore, in the unnecessary area mask processing (monitoring area setting), the area over which the sweetfish jumps over the platform is the detection target area. Therefore, the monitoring area avoids noise images such as dust from the falling part of the waterway to the upstream. Set. As a result, erroneous detection due to unnecessary areas can be avoided in advance.
Further, in the extraction process of sweetfish candidates, preprocessing is performed with a filter or the like in order to alleviate erroneous detection due to water surface unevenness within the detection region, and then a bright component is extracted by binarization processing.
[0015]
Further, in the sweetfish discrimination process, the size of the extracted area is measured, and the one whose size is predefined as sweetfish is judged as sweetfish.
In the present invention, it is possible to measure the number of ascending similarly for fishes other than sweetfish by performing imaging and image processing in accordance with the action pattern of ascending on the fishway.
In the present invention, there are a case where the counting is performed after recording on the video tape, and a case where the counting is performed by directly inputting to the image processing apparatus without recording, and each has the following characteristics.
[0016]
When recording on a videotape, the collected videotape can be reproduced at an office or the like and counted together. Further, there is no need to install an image processing apparatus on site. However, on the other hand, it is necessary to change the videotape regularly.
When inputting directly, it is possible to count in real time. Further, by providing a communication function, the image processing apparatus can be installed at a place away from the site and counted. Furthermore, there is no hassle of changing video tapes. However, on the other hand, it is necessary to install an image processing apparatus on site or to lay a cable from the camera to the place where the image processing apparatus is installed.
[0017]
A major advantage of the present invention is that, since the basic principle of counting is the same as that of visual observation, there is no influence on the natural ecosystem, and counting results can be easily obtained from images such as video recording. It is also possible to record the moment when the sweetfish goes up as a video or an image, and it is possible to check the counting result later using the video.
[0018]
【The invention's effect】
As described above, according to the present invention, the fishway is imaged by the camera, and the number of fishes going up from the picked-up image is counted, thereby making it possible to automate the measurement of the number of going up.
[Brief description of the drawings]
FIG. 1 is a diagram showing a schematic configuration of the present invention.
2 is a block diagram showing an internal configuration of the image processing apparatus in FIG. 1; FIG.
FIG. 3 is a diagram illustrating a processing region of a captured image.
FIG. 4 is an explanatory view showing the upstream operation of sweetfish as seen from the cross section of the fishway.
FIG. 5 is an explanatory diagram showing the sweetfish going up as seen from the top of the fishway.
FIG. 6 is a diagram illustrating an arrangement example of a camera on a fishway.
FIG. 7 is a diagram illustrating an arrangement example of cameras on a fishway.
FIG. 8 is a graph showing an example of an upstream survey.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ITV camera 2 Video tape recorder 3 Video tape 4 Image processing apparatus 5 Display 41 Processing area extraction part 42 Local filter processing part 43 Inter-image difference processing part 44 Binarization part 45 Count part 46 Storage part 61 Weir 62, 63 Fishway

Claims (2)

A camera installed at a position where the fish going up the fishway jumps over the weir and images from the side ;
Means for extracting a detection target region through which the fish passes from an image captured by the camera;
Means for pre-processing the extracted image of the detection target area and binarizing with a predetermined threshold, and detecting a detection object having a size in a range in which the size of the extracted area is defined in advance as a fish shadow ; ,
Means for counting the detected fish shadow and outputting the count value;
An apparatus for measuring the quantity of fish going up a fishway, characterized by comprising: A camera installed at a position where the fish going up the fishway jumps over the weir and images from the side ;
A video recorder for recording images captured by the camera;
A playback device for playing back images recorded in the video recorder;
Means for extracting the detection target region through which the fish passes from the image reproduced by the reproducing device;
Means for pre-processing the extracted image of the detection target area and binarizing with a predetermined threshold, and detecting a detection object having a size in a range in which the size of the extracted area is defined in advance as a fish shadow ; ,
Means for counting the detected fish shadow and outputting the count value;
An apparatus for measuring the quantity of fish going up a fishway, characterized by comprising:

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