JPH11287617A - Position detecting device of fish in water tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect the position of a fish body without extracting a binarized image and easily perform a position detection dispensing with the determination of a threshold by arranging a plurality of light sources on the background of the fish body, and detecting that some of the light sources are shielded by the fish body so as not to be image inputted by luminance distribution. SOLUTION: A plurality of light sources 5 are arranged on the background 4 of a fish 3 bred in water 2 of a water tank 1. The water tank 1, the water 2, and the light sources 5 are image inputted to an image pickup device 7 as a pickup object, and the image signals are converted into electric signals. The electric signals from the image pickup device 7 are processed by an image processing device 8, and stored in an image memory 9 with n-gradation luminance resolution. The position memory 10 of the image processing device 8 stores the position coordinates of the light sources 5. The lacking light source position judging circuit 11 of the image processing device 8 mutually compares the contents of the image memory 9 and the position memory 10 to judge the position of the light source 5 which is shielded by the fish body 3 and not inputted to the image pickup device 7. A position determining circuit 12 determines the position of the fish according to the light sources 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an image processing method for aquatic animals bred using influent water and treated water from a water purification plant or a sewage treatment plant, river water, or the like as test water. The present invention relates to an apparatus for detecting the presence or absence of a poisonous substance in test water depending on a speed.

[0002]

2. Description of the Related Art As disclosed in Japanese Patent Application No. 62-55272 (reference), a conventional apparatus uses a binarized image in which a captured image of a fish is distinguished from an aquatic animal into a background in order to detect the position of the aquatic animal. To recognize aquatic animals.

[0003]

In the above prior art, the method of detecting the position of a fish requires extracting a clear binary image of the fish, so that the background is brightened and the fish is dark. 2 for fish extraction
I was getting a digitized image. In order to make the background bright, an illuminator is arranged on the background. However, it is necessary to provide a considerably strong illumination with respect to the surrounding brightness so as to eliminate the uneven lighting of the background and the influence of light from the surroundings.

[0004] In addition, in order to determine a threshold value for obtaining a binarized image of a fish body, a special method such as determination of a threshold value based on a luminance distribution is required. In addition, when the turbidity is high, a clear binary image cannot be obtained due to irregular reflection of light.

An object of the present invention is to detect a fish body without extracting a binarized image, and to perform the fish body position detection easily without determining a threshold value.

[0006]

An object of the present invention is to arrange a plurality of light sources on a background of a fish body as viewed from an imaging device, and to input an image while some of the plurality of light sources in the background are hidden by the fish body. This can be achieved by detecting that the light source is not present by the luminance distribution and setting the position of the hidden light source as the position of the fish.

That is, the plurality of light sources arranged on the background of the object to be imaged clearly show a higher level of luminance than the background portion other than the light source. For example, a light source is arranged as shown in FIG.
When this part is imaged and processed by the image processing device, FIG.
FIG. 3B shows a luminance distribution for the AA ′ portion in FIG.

Next, as shown in FIG. 4A, when an object that does not transmit light exists between the light source and the imaging device, the light from the light source does not reach the imaging device. The luminance distribution of the portion is as shown in FIG. At this time, if the position of the light source between B and B 'is stored in the image processing device in advance, the position of the light source at which the light from the light source is not taken into the imaging device by the object can be determined.

By the way, light from the light source is not taken into the imaging device. That is, the lack of the light source can be easily determined by the following method. The luminance of the position where the light source should be is extremely smaller than the luminance of the positions of other light sources. Alternatively, when the luminance at the position where the light source should be is smaller than the average luminance of the entire screen, or when the luminance at the position where the light source should be is similar to or smaller than the luminance at the intermediate position between the light sources, the light source depends on the object. You can judge it was hidden.

Therefore, as shown in FIG. 3, if a plurality of light sources are arranged in the background of the object to be imaged and the positions of the light sources are stored in the image processing apparatus, the position of the light source missing by the fish is determined by the luminance distribution of the imaged screen. This allows the position of the fish to be determined.

In addition, when determining whether or not the light source is missing due to the luminance distribution of the image processing apparatus, it is possible to determine whether the illuminance of the light source is increased or decreased based on whether or not the presence of the light source in the entire screen can be determined. In such a case, it is possible to reduce the energy given to the light source so that imaging with the minimum brightness is possible, and it is possible to minimize the energy given to the light source. It is possible to automate the detection of the fish body position.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.

1 is a water tank, 2 is water in the water tank 1, and 3 is a fish which is an aquatic animal bred in the water 2 of the water tank 1. 4 is a background of the fish 3 in the aquarium 1, 5 is a plurality of light sources fixedly arranged in the background portion, and 6 is a part of the light source hidden in the fish 3.

Reference numeral 7 denotes an imaging device for inputting an image with the aquarium 1, water 2, fish 3, and light source 4 as an imaging target and converting an image signal into an electric signal. Image processing device. Reference numeral 9 denotes an image memory of the image processing device 8, which stores an image with a luminance resolution of n gradations (normally n = 256).

Reference numeral 10 denotes a position memory of the image processing device 8, which stores position coordinates of the light source 4. Reference numeral 11 denotes a missing light source position determination circuit of the image processing device 8, which compares the contents of the image memory 9 and the position memory 10 to determine the position of the light source 6 hidden by the fish and not input to the imaging device 7. .

Reference numeral 12 denotes a position determining circuit for determining the position of the fish based on the position of the light source 6 from the missing light source position determining circuit 11.

The image memory 9 stores, on a pixel-by-pixel basis, luminance values ranked with a luminance resolution of n gradations (normally n = 256) based on a signal from the imaging device 7. A pixel is a division capability for one screen from the image pickup device 7, and when a vertical direction is x and a horizontal direction is y, one screen is composed of (x × y) pixels (normally x = 512, y = 512). .

The missing light source position judging circuit 11 judges the absence of a light source based on the luminance of each pixel in the image memory 9 and the coordinates of the light source position in the position memory 10. As a determination method, it is determined that there is no distribution with high luminance at coordinates where the light source should be.

Alternatively, there is a method in which the lack of a light source is determined based on the fact that there is no difference or a low difference in the luminance of the coordinates of the light source with respect to the luminance distribution of the coordinate portion between the light sources.

Next, the coordinates of the missing light source from the missing light source position determining circuit 11 are input to the position determining circuit 12. The position determination circuit 12 determines and determines the position of the fish 3 based on the coordinates of the missing light source.

In making this decision, the missing light source 6
When there are a plurality of the light sources 6, the coordinates of the center of gravity are calculated by using the plurality of light sources 6, and the coordinates of the center of gravity are used as the positions of the fish to determine the position of the fish.

According to the present invention, since the position of the fish is determined without extracting the binarized image in order to determine the position of the fish in the aquarium, the determination of the threshold value is unnecessary and the position can be determined easily.

Next, an embodiment of the light source luminance adjustment according to the present invention will be described with reference to FIG.

In the present embodiment, 13 light source adjusters are added to FIG.
It is provided with a light source luminance determination function 11A.

The missing light source position determining circuit 11 compares the image memory 9 with the position memory 10 in the same manner as in the above embodiment. In the light source luminance determining function 11A, there should be a light source in the entire screen. In consideration of the coordinates and the distribution of the bright light in the portion other than the light source, the light source adjuster 13 is adjusted to increase or decrease the energy supply to the light source so as to obtain the minimum luminance output that can be determined as the light source.

The light source determination method in the light source luminance determination function 11A includes, for a plurality of light sources 5, whether or not the difference between the luminance of the light source portion and the luminance of the intermediate coordinates of the light sources is clear.
Alternatively, it can be easily performed by a method such as that the light source portion is clearly higher in luminance than the average luminance of the entire screen and an image is input, and from this determination, the minimum luminance can be determined so that the light source can be determined as the light source. A signal for increasing or decreasing the luminance is given to the light source adjuster 13.

The light source adjuster 13 increases or decreases the energy (usually electric energy) given to the light source based on the increase / decrease signal from the light source luminance judging function 11A. With this, the energy consumed by the light source can be minimized, and the light source can be controlled in accordance with the state of the water 2 (turbidity state).

According to the embodiment of the present invention, the light source can be controlled according to the condition of the water 2 without extracting a binarized image for determining the position of the fish in the water tank. Energy consumption can be minimized.

[0029]

According to the present invention, two fish bodies can be displayed on the imaging screen.
Since the position of the fish can be detected without extracting it as a digitized image, there is no need to increase the brightness of the background part with excessive illumination from the surroundings of the aquarium, and the position of the fish can be easily detected without having to determine a threshold value. .

[Brief description of the drawings]

FIG. 1 is an explanatory diagram in which a plurality of light sources are arranged on a background in one embodiment of the present invention, and the position of a fish is detected by comparing an image memory with a light source coordinate memory.

FIG. 2 is an explanatory diagram showing a light source luminance judgment function and a light source luminance control of a light source adjuster for the embodiment of FIG.

FIGS. 3 (a) and 3 (b) are explanatory diagrams of a plurality of light source distributions arranged behind a subject to be imaged, and a cross-sectional view taken along line AA ′ of FIG. 3 (a).

FIGS. 4A and 4B are an explanatory view when an object that does not transmit light is present and a cross-sectional view taken along line BB ′ of FIG. 4A;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... water tank, 2 ... water in a water tank, 3 ... fish, 4 ... background, 5 ... light source, 6 ... hidden light source, 7 ... imaging device, 8 ... image processing device, 9 ... image memory, 10 ... position memory Reference numeral 11 denotes a missing light source position determining circuit, 12 a position determining circuit, 11A a light source luminance determining function, 13 a light source adjuster, and 20 an object that does not transmit light.

Claims (1)

[Claims] 1. An aquatic animal bred in an aquarium, an imaging device for converting image information of the aquatic animal into an electric signal, and a plurality of light sources disposed behind the aquatic animal as viewed from the imaging device.
Means for determining the position of the light source missing from the multi-valued image captured by the imaging device and not captured by the imaging device due to the aquatic animal as an image, according to the missing position of the light source,
Means for determining the position of the aquatic animal, arranging the plurality of light sources on the background of the aquatic animal, and determining the position of the aquatic animal as the position of the light source hidden and missing by the aquatic animal. Characteristic fish position detection device in the aquarium.