Fish behavior analysis tank based on camera technology improvement and behavior parameter evaluation method

Abstract

The present application belongs to the field of biological and ecological toxicity monitoring and aquatic organism behavior analysis, and specifically discloses a fish behavior analysis tank improved based on camera technology and a behavior parameter evaluation method. The present application solves the problems of monitoring dead angles and false positives caused by image distortion when a common camera is used to monitor and identify fish bodies. The present application comprises a tank body and a baffle assembly, the inner wall of the baffle assembly is designed to be parallel to the camera light path, the baffle assembly is composed of multiple baffles with gradually changing thickness, and the thickness of the baffles gradually decreases along the direction of the camera light path. The baffle assembly comprises a left baffle and a right baffle, the bottom of the left baffle and the right baffle is provided with a feces groove, and the middle and upper parts of the left baffle and the right baffle are provided with multiple uniformly distributed water inlet and outlet through holes. When the camera light path is in the vertical direction, the baffle assembly further comprises a front baffle and a rear baffle. When the camera light path is in the horizontal direction, the baffle assembly further comprises a bottom baffle and a top baffle.

Description

Technical Field

[0001] This invention belongs to the field of biological and ecotoxicological monitoring and aquatic organism behavior analysis technology, and particularly relates to a fish behavior analysis tank and behavior parameter evaluation method based on improved camera technology. Background Technology

[0002] With societal progress and industrial development, an increasing number of chemicals are being developed to improve human production and living standards. This also leads to a growing number of chemicals entering aquatic environments through various pathways (e.g., discharge, leakage, use). These exogenous chemicals can have multifaceted (nervous, endocrine, reproductive, etc.), multi-level (community, individual, organ, tissue, cell, biomolecule, etc.), and multi-stage (bioaccumulation, biomagnification, bioaccumulation, etc.) effects on aquatic organisms, threatening aquatic ecological health and consequently adversely affecting human health.

[0003] To assess the quality of aquatic environments and ecosystems, water quality monitoring technologies have emerged, and countries worldwide have established limits for water quality parameters (total nitrogen, total phosphorus, ammonia nitrogen, BOD, COD, pH, etc.) for different water bodies. However, with the rapid development of chemical technologies, conventional water quality monitoring indicators cannot accurately reflect the environmental hazards of water bodies. Some pollutants can produce significant toxic effects at very low concentration levels without causing large fluctuations in monitoring parameters.

[0004] The total wastewater flow toxicity (WET) test is a water quality monitoring method proposed by the EPA. This method can obtain data on the toxicity of wastewater to aquatic organisms without identifying specific pollutants, making it a direct and efficient way to determine the harm of wastewater to aquatic life. The same method can also be used for water toxicity assessment and online toxicity monitoring.

[0005] Online toxicity monitoring technology is a monitoring technique based on the stress response of model organisms to abnormal water quality. By monitoring changes in the behavior of these model organisms, it enables early warning of water pollution. Common model organisms include luminescent bacteria, algae, fish, and shellfish. Among these, luminescent bacteria are the most widely used and can be used to evaluate the acute toxicity of water. The "Technical Requirements for Automatic Online Monitoring Instruments for Biological Toxicity of Water (Luminescent Bacteria Method DB44 / T 1946-2016)" specifies the technical requirements for online monitoring of biological toxicity in surface water, groundwater, and other water sources using luminescent bacteria. However, their trophic level is relatively low, making it difficult to directly reflect the comprehensive impact of water quality changes on the entire aquatic ecosystem. Therefore, other aquatic organisms are still needed for toxicity monitoring to supplement the data. Fish, as species with higher trophic levels in aquatic ecosystems, can adapt to slightly polluted water. Unlike algae, daphnia, and microorganisms, the toxicity of water to fish can be determined through behavior, without needing to reach a lethal effect, thus achieving true environmental friendliness in monitoring methods. Small fish model organisms, such as zebrafish, medaka, and rare gudgeon, are a type of model organism that are small in size, have a short development cycle, short experimental cycle, low cost, and small amount of drugs used in experiments. They are widely used in toxicity studies. For example, Chinese invention patent CN105259325A discloses an online monitoring and early warning device that uses zebrafish as a model organism.

[0006] Various technologies exist for online monitoring of biotoxicity using fish as model organisms, including video tracing, four-level impedance monitoring, respiration measurement, bioelectrical effect measurement, electrocardiogram and electroencephalogram (EEG) measurement, and combined technologies with behavioral analysis and other techniques. Among these monitoring technologies, video tracing is relatively intuitive, has low requirements for hardware, can monitor a wide range of items, and is also an important medium for coupling with other technologies. Infrared video tracing is a method that uses an infrared camera to capture infrared light and image it based on the obtained light intensity. It is currently used in the behavioral analysis of juvenile and adult fish. Water and its container are considered bright due to their high light transmittance, while the fish body and the connection between the fish and the container are considered dark due to their low light transmittance. By selecting an appropriate analysis area, fish can be identified.

[0007] Commonly used cameras include ordinary cameras and wide-angle cameras. Wide-angle cameras suffer from image edge distortion, affecting fish identification and quantitative analysis. Ordinary cameras have a wider field of view with increasing distance, but are easily affected by water flow and reflections. Infrared cameras react to container joints and areas where containers meet on the water surface, further affecting fish identification and leading to the loss of monitoring range in the upper water layer. Pollutants can cause fish to escape and rise to the surface, entering monitoring blind spots, resulting in false positives or invalid data. Current technology lacks a low-cost solution to these problems. Summary of the Invention

[0008] One objective of this invention is to provide a fish behavior analysis tank based on improved camera technology, which effectively solves the problems of blind spots and false positives caused by image distortion when using commonly used cameras to monitor and identify fish, as described in the background art.

[0009] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0010] A fish behavior analysis tank based on improved camera technology includes a tank body and a partition assembly. The partition assembly is disposed in the tank body, and the inner wall of the partition assembly is designed parallel to the camera optical path. The partition assembly is composed of multiple partitions with gradually varying thicknesses. The internal space of the partition assembly is the experimental area, and the thickness of the partitions gradually decreases along the camera optical path.

[0011] The baffle assembly includes a left baffle and a right baffle. The inner surfaces of the left and right baffles are trapezoidal in cross-section along the water flow direction. The bottom and sides of the left and right baffles are adapted to fit the bottom wall of the cylinder. The bottom of the left and right baffles is provided with a manure trough. The upper middle part of the left and right baffles is provided with multiple evenly distributed inlet and outlet water passages.

[0012] When the camera optical path is vertical, the partition assembly also includes a front partition and a rear partition, which are tightly fitted to the front and rear side walls of the cylinder, respectively.

[0013] When the camera optical path is horizontal, the partition assembly also includes a bottom partition and a top partition.

[0014] Furthermore, the formula for calculating the thickness of the partition is: In the formula, a represents the thickness difference between the end of the partition closest to the camera and the end furthest from the camera, h1 represents the distance between the camera and the cylinder wall furthest from the camera, h2 represents the height of the partition in the direction of the camera light path, and l represents the distance between the ends of the two partitions furthest from the camera.

[0015] Furthermore, when the camera light path is vertical, the partition assembly is provided with a top cover to prevent fish from escaping the experimental area.

[0016] Furthermore, when the camera optical path is horizontal, the bottom partition is the bottom wall of the cylinder.

[0017] Furthermore, it includes an inlet zone and an outlet zone, wherein the outlet zone is equipped with an internal circulation filter, and the inlet zone is equipped with an aeration device and a wastewater dispersion system.

[0018] Furthermore, the wastewater dispersion system includes a pollutant inlet pipe and a vertically downward-arranged circulating water pipe and aeration components. The pollutant inlet pipe and the circulating water pipe are closely fitted together, and the outlet of the pollutant inlet pipe is higher than the outlet of the circulating water pipe.

[0019] Furthermore, the inner surface of the partition assembly is generally frustum-shaped.

[0020] Furthermore, the cylinder body is made of transparent glass or transparent plastic material, and the partition and top cover are both made of transparent plastic material.

[0021] Furthermore, the plastic is an acrylic plastic without any added endocrine disruptors.

[0022] Furthermore, the volume of the cylinder is not less than 10L, and the length, width, and height of the cylinder do not exceed 50cm.

[0023] Another objective of this invention is to provide a method for evaluating behavioral parameters of a fish behavior analysis tank based on improved camera technology, as described in the above embodiments.

[0024] (a) This is achieved by adding an auxiliary camera perpendicular to the analysis camera to the 2D behavior analysis system.

[0025] I. Analyze the camera shooting vertically and use the auxiliary camera shooting horizontally.

[0026] Quantitatively assess behavioral parameters using a fish behavior analysis tank with the camera beam in a vertical direction, including the following steps:

[0027] A1. Fix the vertical analysis camera directly above the cylinder and ensure that the camera's shooting center is located on the vertical line of the center of the experimental area.

[0028] A2. Fix the horizontal auxiliary camera directly in front of the cylinder body, with the shooting center of the auxiliary camera located on the horizontal center line of the experimental area.

[0029] A3. Record fish behavior videos from both vertical and horizontal shooting directions, and perform trajectory recognition and output behavior parameters. The actual horizontal movement distance of the fish between frame i and frame i+1 is x. i : In the formula, 'a' represents the thickness difference between the top and bottom of the left or right partition, 'h1' represents the distance between the analysis camera and the bottom wall of the cylinder, 'h2' represents the height of the partition in the direction of the camera's optical path, 'l' represents the distance between the bottom of the left and right partitions, and 'S' represents the distance between the bottom of the left and right partitions. iS represents the distance the fish moves in the video image from frame i to frame i+1. This is calculated by connecting the camera to the positions in frames i and i+1, extending the lines to the bottom wall of the tank, and forming the line segment S at the two intersection points with the bottom wall of the tank. i Value, x i H represents the length of the line connecting the starting and ending points of the actual movement trajectory projected onto the bottom wall of the tank, i.e., the actual horizontal movement distance of the fish. i and H i+1 These are the heights of the fish in the i-th and (i+1)-th frames output by the auxiliary camera, respectively.

[0030] If the camera frame rate is 30 frames per second, then the horizontal distance the fish moves per second is: In the formula, X j Let be the total horizontal distance traveled by the fish in the j-th second.

[0031] II. The analysis camera shoots horizontally, while the auxiliary camera shoots vertically.

[0032] Using a fish behavior analysis tank with the camera optical path horizontal, behavioral parameters are quantitatively evaluated. The analysis targets the behavioral parameters when the fish rises or sinks. These behavioral parameters include, but are not limited to, rising or sinking speed, vertical movement distance, dwell time in the upper region, dwell time in the lower region, and swimming height. The analysis includes the following steps:

[0033] B1. Fix the horizontal analysis camera directly in front of the cylinder and ensure that the camera's shooting center is located on the horizontal center line of the experimental area.

[0034] B2. Fix the vertical auxiliary camera directly above the cylinder body, with the camera's shooting center located on the vertical line of the center of the experimental area.

[0035] B3. Record fish behavior videos from both vertical and horizontal shooting directions, and perform trajectory recognition and output behavior parameters.

[0036] A vertically downward auxiliary camera records the distance w of the fish's body from the vertical segment of the tank wall closest to the analysis camera in the i-th frame. i The horizontal analysis camera records the height h of the fish's body from the bottom partition in the i-th frame of the image. i The actual swimming height h of the fish in the i-th frame from the bottom partition is calculated according to formula (4). i ': In the formula, W is the distance between the analysis camera and the cylinder wall away from the analysis camera, and w is the distance difference between the cylinder side wall close to the analysis camera and the cylinder side wall away from the analysis camera, that is, the distance between the front side wall and the rear side wall of the cylinder.

[0037] The upward or downward distance between frame i and frame i+1 is: Δh i =h i+1 '-h i '(5), where h i 'with h i+1 ' represents the actual swimming height of the fish from the bottom partition in the i-th frame and the (i+1)-th frame, respectively.

[0038] The average velocity V and speed v from second j to second k are:

[0039]

[0040] In the formula, V represents the average speed of movement from the j-th second to the k-th second. If the average speed is positive, it means that the fish tends to float upwards from the j-th second to the k-th second; otherwise, it tends to sink downwards.

[0041] v represents the movement speed from the j-th second to the k-th second, indicating the fish's activity level in the vertical direction. The larger the v, the more active the fish is in the vertical direction, and vice versa.

[0042] Δt j-k This represents the time interval, where n represents the frame rate of the camera used.

[0043] (ii) Achieved through a 3D behavior analysis system.

[0044] The fish behavior analysis tank simultaneously meets the requirements of a fish behavior analysis tank when the camera light path is horizontal and when the camera light path is vertical. The fish behavior analysis tank does not require a top partition with varying thickness, and both the left and right partitions gradually become thinner in the direction of the vertical camera light path.

[0045] A first analysis camera and a second analysis camera are set up in the vertical and horizontal directions respectively. The coordinates of the 3D space of each frame are corrected according to formulas (8) to (13). The trajectory is depicted and the 3D spatial distribution is analyzed based on the corrected 3D coordinates of each frame.

[0046] The actual horizontal movement distance of the fish in frame i and frame i+1 is x i : In the formula, 'a' represents the thickness difference between the top and bottom of the left or right partition, 'h1' represents the distance between the first analysis camera and the bottom wall of the cylinder, 'j2' represents the height of the partition in the direction of the camera's optical path, 'l' represents the distance between the bottom of the left and right partitions, and 'S' represents the distance between the bottom of the left and right partitions. iS represents the distance the fish moves in the video image from frame i to frame i+1. It is the line segment formed by connecting the first camera to the positions of frames i and i+1, extending to the horizontal plane at the bottom of the tank, and the two intersection points with the horizontal plane at the bottom of the tank. i Value, x i H represents the length of the line connecting the starting and ending points of the actual movement trajectory projected onto the bottom partition, i.e., the actual horizontal movement distance of the fish. i and H i+1 These are the heights of the fish in the i-th and (i+1)-th frames output by the second analysis camera, respectively.

[0047] If the frame rate of the first analysis camera is 30 frames / s, then the horizontal distance the fish moves per second is: In the formula, X j Let be the total horizontal distance traveled by the fish in the j-th second.

[0048] The actual swimming height h of the fish from the bottom partition in frame i i ': In the formula, W represents the distance between the second analysis camera and the cylinder wall away from the second analysis camera, and w represents the distance difference between the cylinder sidewall close to the second analysis camera and the cylinder sidewall away from the second analysis camera, that is, the distance between the front sidewall and the rear sidewall of the cylinder. i This represents the vertical distance between the fish in the i-th frame recorded by the first analysis camera and the tank wall on the side closest to the second analysis camera.

[0049] The upward or downward distance between frame i and frame i+1 is: Δh i =h i+1 '-h i '(11), where h i 'with h i+1 ' represents the actual swimming height of the fish from the bottom partition in the i-th frame and the (i+1)-th frame, respectively.

[0050] The average velocity V and speed v from second j to second k are:

[0051]

[0052] In the formula, V represents the average speed of movement from the j-th second to the k-th second. If the average speed is positive, it means that the fish tends to float upwards from the j-th second to the k-th second; otherwise, it tends to sink downwards.

[0053] v represents the movement speed from the j-th second to the k-th second, indicating the fish's activity level in the vertical direction. The larger the v, the more active the fish is in the vertical direction, and vice versa.

[0054] αtj-k This represents the time interval, where n represents the frame rate of the camera used.

[0055] Compared with the prior art, the beneficial technical effects of the present invention are:

[0056] (1) By designing a partition assembly parallel to the camera optical path, this invention ensures that pollutants are diffused evenly while eliminating blind spots in the monitoring range and achieving comprehensive coverage of behavior monitoring. At the same time, the proposed quantitative evaluation method for behavior parameters can improve the accuracy of data, effectively reduce the error of fish movement parameters on different cross sections caused by image deformation, and greatly eliminate false negative or false positive results caused by the camera optical path. This provides technical support for the realization of reliable water quality monitoring of different water bodies and non-destructive toxicity assessment of chemicals.

[0057] (2) This invention uses acrylic perforated baffles with gradually varying thickness as inlet / outlet baffles and tank wall baffles, which can be coupled with a video behavior analysis system to locate the actual position based on the real-time video footage, ensuring that the activity range of the fish is within the monitoring area. At the same time, it helps to disperse pollutants entering the water and provides the fish with sufficient activity space, enabling the analysis of behaviors that are difficult to count or observe in small containers, such as escape and turning.

[0058] (3) The present invention avoids monitoring blind spots by setting a partition component parallel to the optical path of the monitoring camera, which is lower in cost and simpler in hardware setup, and conforms to the principle of lightweight design.

[0059] Using the behavior of fish in aquaculture waters under long-term stable monitoring as a baseline, the differences in fish stress-induced movement and behavior caused by abnormal water quality exposure reflect changes in water quality in real time, and are used to monitor the biotoxicity of abnormal water bodies.

[0060] Using the behavior of fish in target natural water bodies or long-term stable external discharges that meet national emission standards as a baseline, abnormal behavior can reveal the ecotoxicity of abnormal water bodies. Setting an appropriate baseline can avoid false positive results, avoid testing errors caused by individual differences, reduce the number of animals used, and better conform to the 3R principle.

[0061] (4) This invention has promising applications in fish behavior analysis technology based on camera tracing. As a fixed component of a camera-based fish behavior analysis system, it can effectively solve the problem of blind spots caused by the inherent technical characteristics of cameras. Combined with the behavioral parameter evaluation method proposed in this invention, it greatly avoids false positives and invalid results, making it particularly suitable for the toxicology of pollutants, chemicals, and drugs. Simultaneously, this invention also has application value in the field of online monitoring of the biotoxicity and ecotoxicity of polluted water, especially wastewater from the petroleum and petrochemical industries, and can reduce the false alarm rate. Attached Figure Description

[0062] Figure 1 This is a schematic diagram of the structure of the fish behavior analysis tank with a vertical camera optical path according to the present invention.

[0063] Figure 2 yes Figure 1 A schematic diagram of the structure of all the partitions.

[0064] Figure 3 This is a schematic diagram of the fish behavior analysis tank with a horizontal camera optical path according to the present invention, as well as its left side partition, right side partition and top partition.

[0065] Figure 4 This is a schematic diagram of the fish behavior analysis tank and its partition assembly, which realizes the evaluation of fish behavior parameters through a 3D behavior analysis system according to the present invention.

[0066] Figure 5 yes Figure 4 Left view of the left side panel.

[0067] Figure 6 This is a schematic diagram of the movement time and water intake time of a zebrafish using a conventional partition in Comparative Example 1 of this invention.

[0068] Figure 7 This is a schematic diagram of the movement time and water intake time of a zebrafish using the partition described in Example 1 of the present invention with pure water intake.

[0069] List of reference numerals in the attached diagram: 1. Cylinder body; 4. Left side partition; 5. Right side partition; 6. Manure trough; 7. Inlet / outlet water passage; 8. Front partition; 9. Rear partition; 10. Bottom partition; 11. Top partition. Detailed Implementation

[0070] Implementation Method 1

[0071] A fish behavior analysis tank based on improved camera technology includes a tank body 1 and a partition assembly. The partition assembly is disposed inside the tank body 1. Preferably, the inner surface of the partition assembly is frustum-shaped.

[0072] The inner wall of the partition assembly is designed parallel to the camera optical path. The partition assembly is composed of multiple partitions with gradually varying thicknesses. The internal space of the partition assembly is the experimental area. The thickness of the partitions gradually decreases along the camera optical path.

[0073] The baffle assembly includes a left baffle 4 and a right baffle 5. The inner surfaces of both the left baffle (inlet baffle) 4 and the right baffle (outlet baffle) 5 have trapezoidal cross-sections along the water flow direction. The bottom and sides of both the left baffle 4 and the right baffle 5 are fitted to the bottom wall of the tank. A waste trough 6 is provided at the bottom of both the left baffle 4 and the right baffle 5 to quickly discharge fish waste using hydraulic and gravitational forces. Because the baffle is thicker at the top and thinner at the bottom, pollutants tend to flow in from the bottom rather than the top. To ensure more homogeneous water flow, multiple evenly distributed inlet and outlet holes 7 are provided in the upper middle part of both the left baffle 4 and the right baffle 5.

[0074] like Figure 1 and Figure 2 As shown, when the camera optical path is vertical, the partition assembly also includes a front partition 8 and a rear partition 9, which are tightly fitted to the front and rear side walls of the cylinder 1, respectively.

[0075] Preferably, when the camera optical path is vertical, the partition assembly is provided with a top cover to prevent fish from escaping the experimental area.

[0076] like Figure 3 As shown, when the camera optical path is horizontal, the partition assembly also includes a bottom partition 10 and a top partition 11.

[0077] Preferably, when the camera optical path is horizontal, the bottom partition 10 is the bottom wall of the cylinder.

[0078] In some specific embodiments, the cylinder body is made of highly transparent glass or highly transparent plastic material, and the partition and top cover are both made of highly transparent plastic material.

[0079] Preferably, the plastic is an acrylic plastic without added endocrine disruptors such as bisphenol A.

[0080] In some specific embodiments, the volume of the cylinder is not less than 10L, and the length and width of the cylinder do not exceed 50cm. To reduce the errors caused by camera distortion and partitions, the height of the cylinder does not exceed 50cm, that is, the length of the cylinder does not exceed 50cm in any shooting direction (vertical and horizontal).

[0081] The thickness of the baffle is determined based on the actual dimensions of the cylinder and the height of the camera, and the specific calculation formula is as follows: In the formula, 'a' represents the thickness difference (cm) between the end of the partition closest to the camera and the end furthest from the camera; 'h1' represents the distance (cm) between the camera and the tank wall furthest from the camera; 'h2' represents the height (cm) of the partition along the camera's optical path; and 'l' represents the distance (cm) between the ends of the two partitions furthest from the camera (i.e., the distance between the partitions on the side where the fish's maximum activity area is located). It is worth noting that all variables here are parameters under the same view, such as the thickness of the left and right partitions corresponding to the main view. Specifically, for example... Figure 1 As shown, Figure 1 The left baffle (inlet baffle) 4 and the right baffle (outlet baffle) 5 shown in the image are a set of opposing baffles. The distance between the parallel lines where their bottoms (the baffles are inside the tank bottom) lie is l, and the difference between the top thickness and the bottom thickness of the left and right baffles is a. Figure 1 The bottom thickness of the partition is 0, so the top thickness is a. h1 is the vertical distance from the camera to the bottom of the cylinder, and h2 is the height of the partition (the height of the cylinder).

[0082] In some specific implementations, considering that the water body should be suitable for fish to live in for extended periods, an internal circulation filter is installed in the effluent area, and an aeration device and wastewater dispersion system are installed in the influent area. The hydraulic flow generated during operation by the internal circulation filter and aeration device accelerates the homogenization of the water body and the removal of excrement.

[0083] The wastewater dispersion system includes a pollutant inlet pipe, a vertically downward-facing circulating water pipe, and an aeration assembly. The pollutant inlet pipe and the circulating water pipe are tightly fitted together, with the outlet of the pollutant inlet pipe higher than the outlet of the circulating water pipe. After the pollutants enter the system, they are mixed downwards by the circulating water at a flow rate of approximately 1000 L / h. Simultaneously, irregular bubbles generated by aeration can carry the wastewater upwards, creating a bidirectional dispersion force that achieves pre-mixing in the inlet zone.

[0084] Taking the camera optical path as a vertical direction as an example, since the partition is designed with a structure that is wider at the top and narrower at the bottom, the resistance at the top will be relatively large. In order to prevent the pollutants from concentrating at the bottom due to the large resistance, multiple evenly distributed inlet and outlet water passages are set in the upper middle part of the left partition (inlet partition) and the right partition (outlet partition). The hole diameter is 2mm and the hole spacing is 2mm. The diluted pollutants enter the experimental area through the inlet and outlet water passages and diffuse in both horizontal and vertical directions under the action of gravity and the action of the circulating water pump in the outlet area. Since there are fish swimming in the experimental area, the uncertain disturbance of the pollutants is enhanced, and the dispersion process of the pollutants is accelerated.

[0085] Implementation Method 2

[0086] The fish behavior analysis tank based on improved camera technology described in Implementation 1 is fully compatible with 2D video tracking behavior analysis performed by the upper camera, and can also be coupled with the horizontal camera for 3D behavior analysis. It is worth noting that the upper part of the horizontal camera has not been corrected for the camera optical path, so there are still some blind spots in the monitoring, but the monitoring blind spots in the overall analysis area have been greatly reduced.

[0087] Similarly, it can be used as follows: Figure 3 The partition assembly shown is used to correct the horizontal shooting optical path and analyze the movement patterns of fish in the vertical direction. Its size calculation method is also applicable to formula (1). This partition assembly is suitable for 2D camera tracking behavior analysis when the camera is shooting in the horizontal direction.

[0088] A method for evaluating behavioral parameters of a fish behavior analysis tank based on improved camera technology, as described in Embodiment 1, requires appropriate size conversion to obtain accurate behavioral parameter data because the dimensions of each cross-section along the shooting path are inconsistent, while the area selected for shooting and monitoring is fixed.

[0089] The behavioral parameter evaluation method can be implemented using an auxiliary camera perpendicular to the analysis camera in a 2D behavioral analysis system, or it can be implemented using a 3D behavioral analysis system. The specific methods are as follows:

[0090] (a) This is achieved by adding an auxiliary camera perpendicular to the analysis camera to the 2D behavior analysis system.

[0091] (I) Analyze the camera shooting in the vertical direction and assist the camera shooting in the horizontal direction.

[0092] When the camera's optical path is vertical, such as Figure 1 and Figure 2 The fish behavior analysis tank shown quantitatively assesses behavioral parameters, including the following steps:

[0093] A1. Fix the vertical analysis camera directly above the cylinder and ensure that the camera's shooting center is located on the vertical line of the center of the experimental area.

[0094] The height of the analysis camera from the bottom of the tank is h1, the height of the partition is h2, the difference between the top and bottom of the partition is a, the bottom distance of the maximum activity area of ​​the fish (experimental area) is l, and the top distance of the maximum activity area of ​​the fish (experimental area) is l-2a. The height of the tank, the analysis camera, and the size of the partition must all conform to the relationship described in formula (1).

[0095] A2. Fix the horizontal auxiliary camera directly in front of the tank, with its shooting center located on the horizontal line of the center of the experimental area. This ensures that the video image of the experimental area in the horizontal direction is centered within the overall shooting area. Since the horizontal camera is an auxiliary camera, the distance is not strictly required; it only needs to be able to identify the position of the fish.

[0096] A3. Record videos of fish behavior in both vertical and horizontal shooting directions, and perform trajectory recognition and output behavior parameters.

[0097] The trajectory of the fish in the video output was analyzed, and the movement distance was determined according to a set scale. The scale was set based on the distance between the bottom of the inlet and outlet baffles, i.e., the side length of the experimental area in the video image was set to l. The output interval was one frame, and the movement distance of the fish in the video image between the i-th frame and the (i+1)-th frame was defined as S. i The auxiliary video output shows the height H of the fish's body from the bottom of the tank in the i-th frame. i .

[0098] The shooting partition will have a slight arc deformation, but the deformation is negligible if the shooting distance is sufficient. Therefore, the shooting area is a near-conical area, and the movement of fish in all directions can be calculated by the following formula.

[0099] The actual horizontal movement distance of the fish in frame i and frame i+1 is x i : In the formula, 'a' represents the thickness difference between the top and bottom of the left or right partition, 'h1' represents the distance between the analysis camera and the bottom wall of the cylinder, 'h2' represents the height of the partition in the direction of the camera's optical path, 'l' represents the distance between the bottom of the left and right partitions, and 'S' represents the distance between the bottom of the left and right partitions. i S represents the distance the fish moves in the video image from frame i to frame i+1. This is calculated by connecting the camera to the positions in frames i and i+1, extending the lines to the bottom wall of the tank, and forming the line segment S at the two intersection points with the bottom wall of the tank. i Value, x i H represents the length of the line connecting the starting and ending points of the actual movement trajectory projected onto the bottom wall of the tank, i.e., the actual horizontal movement distance of the fish. i and H i+1 These are the heights of the fish in the i-th and (i+1)-th frames output by the auxiliary camera, respectively.

[0100] If the camera frame rate is 30 frames per second, then the horizontal distance the fish moves per second is: In the formula, X jLet be the total horizontal distance traveled by the fish in the j-th second. By accumulating the distance traveled per second, the distance traveled over longer time intervals can be obtained, and the speed of movement within the corresponding time interval can be calculated.

[0101] (II) Analyze the camera shooting in the horizontal direction and the auxiliary camera shooting in the vertical direction.

[0102] When the camera's optical path is horizontal, such as Figure 3 The fish behavior analysis tank shown quantitatively assesses behavioral parameters. The analysis target is the behavioral parameters of the fish when it rises or sinks. These behavioral parameters include, but are not limited to, rising or sinking speed, vertical distance, time spent in the upper region, time spent in the lower region, and swimming height. The analysis includes the following steps:

[0103] B1. Fix the horizontal analysis camera directly in front of the cylinder and ensure that the camera's shooting center is located on the horizontal center line of the experimental area.

[0104] B2. Fix the vertical auxiliary camera directly above the cylinder body, with the camera's shooting center located on the vertical line of the center of the experimental area.

[0105] B3. Record fish behavior videos from both vertical and horizontal shooting directions, and perform trajectory recognition and output behavior parameters.

[0106] A vertically downward auxiliary camera records the distance w of the fish's body from the vertical segment of the tank wall closest to the analysis camera in the i-th frame. i The horizontal analysis camera records the height h of the fish's body from the bottom partition in the i-th frame of the image. i The actual swimming height h of the fish in the i-th frame from the bottom partition is calculated according to formula (4). i ': In the formula, W is the distance between the analysis camera and the tank wall away from the analysis camera, and w is the distance difference between the tank side wall near the analysis camera and the tank side wall away from the analysis camera, that is, the distance between the front side wall and the rear side wall of the tank. Since the experimental fish are located in the upper half or the lower half of the experimental area, but through calculation, it is found that the calculation formula after the calculation is the same for both cases, so no classification discussion is made here.

[0107] The upward or downward distance between frame i and frame i+1 is: Δh i =h i+1 '-h i '(5), where h i 'with h i+1 ' represents the actual swimming height of the fish from the bottom partition in frame i and frame (i+1), respectively. If Δh iA value greater than 0 indicates the object will float upwards, while a value greater than 0 indicates it will sink downwards.

[0108] The average velocity V and speed v from second j to second k are:

[0109]

[0110] In the formula, V represents the average speed of movement from the j-th second to the k-th second. If the average speed is positive, it means that the fish tends to float upwards from the j-th second to the k-th second; otherwise, it tends to sink downwards.

[0111] v represents the movement speed from the j-th second to the k-th second, indicating the fish's activity level in the vertical direction. The larger the v, the more active the fish is in the vertical direction, and vice versa.

[0112] Δt j-k This represents the time interval, where n represents the frame rate (frames per second) of the camera used.

[0113] (ii) Achieved through a 3D behavior analysis system.

[0114] like Figure 4 As shown, the fish behavior analysis tank simultaneously meets the requirements for a fish behavior analysis tank when the camera light path is horizontal and when the camera light path is vertical. The fish behavior analysis tank does not require a top partition with varying thickness, as... Figure 5 As shown, both the left partition (inlet partition) and the right partition (outlet partition) gradually become thinner in the direction of the vertical camera optical path.

[0115] A first analysis camera and a second analysis camera are set up vertically and horizontally, respectively, and both analysis cameras simultaneously output corresponding auxiliary parameters (such as the height H of the fish body from the bottom of the tank in the i-th frame image output by the second analysis camera). i The distance w between the fish body and the tank wall on one side of the second analysis camera in the i-th frame output by the first analysis camera. i Therefore, each direction can be analyzed independently. The coordinates of the 3D space of each frame are corrected according to formulas (8) to (13), and the trajectory is depicted and the 3D spatial distribution is analyzed based on the corrected 3D coordinates of each frame.

[0116] The actual horizontal movement distance of the fish in frame i and frame i+1 is x i : In the formula, 'a' represents the thickness difference between the top and bottom of the left or right partition, 'h1' represents the distance between the first analysis camera and the bottom wall of the cylinder, and 'h' represents the distance between the top and bottom of the cylinder. i The height of the partition represents the direction of the camera's optical path for the first analytical camera; l represents the distance between the bottom ends of the left and right partitions; S represents the distance between the bottom ends of the left and right partitions.i S represents the distance the fish moves in the video image from frame i to frame i+1. It is the line segment formed by connecting the first camera to the positions of frames i and i+1, extending to the horizontal plane at the bottom of the tank, and the two intersection points with the horizontal plane at the bottom of the tank. i Value, x i H represents the length of the line connecting the starting and ending points of the actual movement trajectory projected onto the bottom partition, i.e., the actual horizontal movement distance of the fish. i and H i+1 These are the heights of the fish in the i-th and (i+1)-th frames output by the second analysis camera, respectively.

[0117] If the frame rate of the first analysis camera is 30 frames / s, then the horizontal distance the fish moves per second is: In the formula, X j Let be the total horizontal distance traveled by the fish in the j-th second.

[0118] The actual swimming height h of the fish from the bottom partition in frame i i ': In the formula, W represents the distance between the second analysis camera and the cylinder wall away from the second analysis camera, and w represents the distance difference between the cylinder sidewall close to the second analysis camera and the cylinder sidewall away from the second analysis camera, that is, the distance between the front sidewall and the rear sidewall of the cylinder. i This represents the vertical distance between the fish in the i-th frame recorded by the first analysis camera and the tank wall on the side closest to the second analysis camera.

[0119] The upward or downward distance between frame i and frame i+1 is: Δh i =h i+1 '-h i '(11), where h i 'with h ii1 ' represents the actual swimming height of the fish from the bottom partition in the i-th frame and the (i+1)-th frame, respectively.

[0120] The average velocity V and speed v from second j to second k are:

[0121]

[0122] In the formula, V represents the average speed of movement from the j-th second to the k-th second. If the average speed is positive, it means that the fish tends to float upwards from the j-th second to the k-th second; otherwise, it tends to sink downwards.

[0123] v represents the movement speed from the j-th second to the k-th second, indicating the fish's activity level in the vertical direction. The larger the v, the more active the fish is in the vertical direction, and vice versa.

[0124] Δt j-k This represents the time interval, where n represents the frame rate of the camera used.

[0125] This invention limits the movement range of experimental fish by setting up a harmless partition assembly, and aligning the partition with the optical path direction. This avoids the blind spots that conventional cameras create in fish behavior analysis, allowing for complete and accurate recording of wall-hugging movements, escape behaviors, and bottom-diving behaviors. It overcomes the hardware limitations of camera-based fish behavior analysis, avoiding false positives or invalid results. Further explanation follows with specific embodiments, test examples, and comparative examples.

[0126] Example 1

[0127] This embodiment develops an analysis tank suitable for the Viewpoint ZebraTower 2D zebrafish behavior observation tower. The fish behavior analysis tank designed in this embodiment is made of highly transparent glass, with internal dimensions of 40*22*25cm and a volume of 22L. This meets the size requirements proposed in Embodiment 1, and the tank wall thickness is 0.5cm.

[0128] The partition assembly is made of acrylic material, and its design and perforations are as follows: Figure 2 As shown, both the left side panel (inlet panel) and the right side panel (outlet panel) are rectangular in the side view direction. Both the left side panel (inlet panel) and the right side panel (outlet panel) have a manure trough at the bottom, which is intended to use water force and gravity to discharge fish excrement and reduce the difficulty of zebrafish image recognition.

[0129] Because the upper part of the baffle is thick and the lower part is thin, the upper part has greater water flow resistance and the lower part has less resistance. Pollutants tend to flow in from the lower part rather than the upper part. In order to make the pollutant water flow uniform, the inlet and outlet baffle is perforated only in the upper half. The size of the contaminated area is 21*22*25cm, and the distance from the camera to the bottom of the tank is 92.9cm. According to formula (1), the top thickness of the inlet and outlet baffle should be 2.83cm more than the bottom thickness, and the top thickness of the front and rear baffles should be 2.96cm more than the bottom thickness. The zebrafish's movable area is fixed as a regular square truncated pyramid by the baffle assembly. The top and bottom surfaces of the truncated pyramid are both rectangular. The top surface size is 15.34*16.03cm, the bottom surface size is 21*22cm, the height of the truncated pyramid is 25cm, and the centers of the top and bottom surfaces are located on the same vertical line.

[0130] The internal circulation filter and the pollutant dispersion device are placed in the outlet and inlet water areas, respectively. The pollutant dispersion device includes an aeration component, a sewage inlet pipe, and a circulation filter outlet pipe. The hydraulic flow during their operation accelerates the homogenization of the water and the removal of excrement. A heating rod is additionally installed in the inlet water area to stabilize the water temperature for zebrafish farming.

[0131] The internal circulation filter is a modified miniature submersible pump with a head of 1.4m and a flow rate of 1000L / h. The outlet is vertically upward. An acrylic microporous plate is installed on the pump-water contact surface to filter large impurities. Aquaculture-specific bio-cotton is placed outside the plate to absorb and filter fish excrement. The plate and bio-cotton face the sidewall of the outlet area and are secured with acrylic clips. A food-grade silicone tube connects to the submersible pump outlet, with the other end connected to the inlet area. An opening is made 2cm from the inlet opening, into which a slanted PVC pipe (0.2cm inner diameter) is inserted, with the slant facing the proximal end. The PVC pipe connects to a food-grade silicone hose to the air, and an air volume regulating valve is installed to adjust the aeration rate. The circulation water pipe is secured with clips, ensuring the pipe opening is vertically downward.

[0132] Test Example 1

[0133] The method described in Example 1 is used to construct a fish behavior analysis tank, which is applicable to the quantitative assessment of behavioral parameters of the Viewpoint ZebraTower 2D zebrafish behavior observation tower.

[0134] (1) Shooting vertically downwards (i.e.) Figure 1 When the analysis direction is the top-down view, a horizontal auxiliary camera is selected as the positioning image. Here, the camera built into the ZebraTower is used as the analysis camera, and the behavioral parameters are quantitatively output through the Viewpoint software. A regular color camera with a resolution of 1288*964 and a frame rate of 30 frames per second is used as an auxiliary camera to record the height data of the zebrafish.

[0135] (2) A fixed horizontal auxiliary camera is located on the front of the cylinder block, with the shooting direction being... Figure 1 As shown in the main view, the auxiliary camera's shooting center is located on the horizontal line of the zebrafish's activity area, ensuring that the video image of the zebrafish's activity area in the horizontal direction is centered within the overall shooting area. Since the horizontal camera is an auxiliary camera, the distance is not strictly required; it only needs to be able to identify the zebrafish's position. In this test case, to minimize horizontal deformation, the auxiliary camera is positioned 1.24m from the aquarium wall.

[0136] (3) Record videos of fish behavior in both vertical and horizontal shooting directions, and perform trajectory recognition and output behavioral parameters. Analyze the trajectory of the zebrafish output from the video, and the movement distance according to the set scale. The scale is set with the distance from the bottom of the inlet / outlet baffle as the standard, that is, the side length of the experimental area in the video image is set to l, and the output interval is every frame. The movement distance of the fish body output on the video image between the i-th frame and the i+1-th frame is defined as S. i The auxiliary video output shows the height H of the fish's body from the bottom of the tank in the i-th frame. i .

[0137] The shooting partition will have a slight arc deformation, but this deformation is negligible if the shooting distance is sufficient. Therefore, the shooting area is a region close to a cone. The movement of the zebrafish in all directions can be calculated. The actual horizontal movement distance between the i-th frame and the (i+1)-th frame is calculated using formula (2) as x. i .

[0138] Since the minimum recording time for Viewpoint output is 1 second, we use the distance moved per second as the minimum time interval, that is, the horizontal distance moved between the i-th second and the (i+1)-th second is denoted as x. i The height of the camera output at the start and end of each second is calculated using formula (2). Here, we take a 1-minute output as an example and correct the motion distance of the Viewpoint output using formula (2). The output results are shown in Table 1.

[0139] Table 1 Results of Test Example 1 before and after correction of motion parameters

[0140]

[0141] Overall, the corrected motion distance is less than the directly output motion distance. This is because the distance between the analysis camera and the cylinder bottom is greater than the projected distance. The higher the height, the greater the reduction in the corrected motion distance compared to the output motion distance, and the linear correlation between the reduction rate and the height is strong (R0). 2 =0.9999), which also indicates that as the height of the zebrafish increases, the error between the output motion parameters and the actual values ​​becomes larger. This may produce some false positive or false negative results. For example, the zebrafish may swim at a normal speed at the water surface, but according to the error caused by the set scale and projection, the zebrafish may swim at a higher speed. At the same time, in a conventional cubic aquarium, zebrafish are very likely to leave the monitoring range and enter the area close to the tank wall and partition near the water surface. The loss of video recognition will cause changes in the data of zebrafish movement distance, movement frequency, and movement time, which may be identified as abnormal behavior.

[0142] Example 2

[0143] The analysis was performed horizontally using an analytical camera (3840*2160 resolution, 25 frames / s). The camera was positioned 70cm from the near-end of the tank wall and fixed to a metal frame. Rubber anti-slip pads were placed on the bottom of the frame, which was then placed on the same experimental platform as the fish behavior analysis tank. The contaminated area of ​​the tank was positioned in the center of the frame to ensure that the tank was centered in the video image captured by the analytical camera. A 1280*720 resolution camera was used for positioning.

[0144] The cylinder body adopts an experimental cylinder with internal dimensions of 40*25*25cm, and the baffle assembly is designed according to... Figure 3 To carry out the design.

[0145] The dimensions of the facade of the contaminated area away from the analysis camera are set to 25*25cm, meaning the distance from the parallel line where the narrower end of the partition is located is 25cm, and the height is the same as the cylinder body. The relative distance to the cylinder wall in the direction of the camera's optical path is also 25cm. According to formula (1), the thickness difference between the top (wider side) and bottom (narrower side) of the left partition, right partition, top partition, and bottom partition is calculated to be 4.46cm.

[0146] The internal circulation filter is a modified miniature submersible pump with a head of 1.4m and a flow rate of 1000L / h. The outlet is vertically upward. An acrylic microporous plate is installed on the pump-water contact surface to filter large impurities. Aquaculture-specific bio-cotton is placed outside the plate to absorb and filter fish excrement. The plate and bio-cotton face the sidewall of the outlet area and are secured with acrylic clips. A food-grade silicone tube connects to the submersible pump outlet, with the other end connected to the inlet area. An opening is made 2cm from the inlet opening, into which a slanted PVC pipe (0.2cm inner diameter) is inserted, with the slant facing the proximal end. The PVC pipe connects to a food-grade silicone hose to the air, and an air volume regulating valve is installed to adjust the aeration rate. The circulation water pipe is secured with clips, ensuring the pipe opening is vertically downward.

[0147] Test Example 2

[0148] A method for quantitatively evaluating behavioral parameters applicable to the fish behavior analysis tank built in Example 2: (1) When the analysis direction is horizontal shooting, an auxiliary camera that shoots vertically downwards is selected as the positioning image.

[0149] (2) The horizontally fixed analysis camera is positioned on the horizontal line of the center of the fish activity area. W is the distance between the tank wall near the analysis camera and the tank wall far from the analysis camera, and w is the difference in distance between the tank side wall near the analysis camera and the tank side wall far from the analysis camera. The tank height, camera height, and partition size must all conform to the relationship described in formula (1).

[0150] (3) A fixed vertical auxiliary camera is positioned directly above the tank. The camera's shooting center is on the vertical line from the center of the fish activity area, ensuring that the video image of the fish activity area in the vertical direction is centered on the overall shooting area. Since the vertical camera is an auxiliary camera, the distance is not strictly required; it is only necessary to be able to identify the fish's position. To reduce errors caused by deformation in this shooting direction, the shooting distance is increased as much as possible. In this test example, the distance between the auxiliary camera and the top of the tank is 1.4m.

[0151] (4) Record fish behavior videos in vertical and horizontal shooting directions and perform trajectory recognition and output behavior parameters.

[0152] The video output shows the trajectory of the fish and the movement distance based on a set scale. The scale is set with the relative distance to the bottom of the partition (the narrower side) away from the tank wall of the analysis camera as the standard. A vertically downward auxiliary camera records the distance w of the vertical segment from the fish body to the tank wall closest to the analysis camera in the i-th frame. i The horizontal analysis camera records the height h of the fish's body from the bottom partition in the i-th frame of the image. i .

[0153] The actual swimming height of the fish from the bottom partition (i.e., the sloping bottom of the tank) in the i-th frame is calculated using formula (4). Since the height change in each frame is analyzed, and there are 25 frames per second, only the analysis results for 5 seconds are shown, as shown in Table 2. The model fish used in this test case is the medaka.

[0154] Table 2 Results of Test Example 2 before and after correction of motion parameters

[0155]

[0156]

[0157]

[0158] The analysis camera used was operating at 25 frames per second, and the analysis lasted for 5 seconds. The h values ​​for each frame were statistically analyzed. i w i The value of h is obtained by calculating h according to formula (4). i’ Δh is calculated according to formula (5). i V is calculated according to formula (6). It can be seen that as w... i The increase of h i 'with h i The smaller the difference, the more accurate the height of the fish from the bottom of the inclined tank can be output using this method. It is particularly effective in recognizing bottom-diving behavior near the analysis camera, which can improve the accuracy of behavior analysis results and reduce the possibility of false negative results.

[0159] Example 3

[0160] A monitoring camera (resolution 2560×1440, frame rate 30 frames / s) is used for horizontal monitoring. The container is a tank with the same length, width and height as in Example 1. Since the horizontal shooting does not directly shoot the bottom of the tank, the fish excrement has little impact on it. The sloping design is the same as the optical path correction partition design. The monitoring direction is perpendicular to the 40*25cm plane and 50cm away from the near end of the tank wall. The monitoring camera is fixed to the observation table with nuts.

[0161] Left and right side partition design as Figure 3 As shown, horizontal shooting correction does not require front and rear side partitions. The sloping bottom wall of the tank acts as the bottom partition of the partition assembly, requiring only an additional top partition. However, due to inconvenience in installation and removal, insufficient fixation, and inability to observe fish surface behavior, the top partition can be omitted. All partitions are the same length, 22cm. The front (near the camera) thickness of all partitions is 3.71cm, and the rear thickness is 0.5cm. The bottom sloping surface is similar, with the front side being 3.21cm higher than the rear. To avoid hydraulic resistance, water inlet and outlet holes are provided in the half of the side partitions near the camera.

[0162] Because the top baffle reduces the water volume in the tank and increases water flow efficiency due to the baffle's constraint, the internal circulation filter parameters were adjusted. A miniature submersible pump with a head of 1.2m and a flow rate of 800L / h was used, with the outlet vertically upwards. An acrylic microporous plate was installed on the pump-water contact surface to filter large impurities. Aquaculture-specific bio-cotton was placed outside the plate to absorb and filter fish excrement. The plate and bio-cotton faced the sidewall of the outlet area and were secured with acrylic clips. A food-grade silicone tube was connected to the submersible pump outlet, with the other end connected to the inlet area. An opening was made 2cm from the inlet opening, into which a slanted PVC pipe (0.2cm inner diameter) was inserted, with the slant facing the proximal end. The PVC pipe was connected to a food-grade silicone hose to the air, and an air volume regulating valve was installed to adjust aeration. The circulation water pipe was secured with clips, ensuring the pipe opening was vertically downwards.

[0163] Example 4

[0164] A fish behavior analysis tank suitable for Viewpoint's 2D zebrafish behavior observation tower was developed. The designed analysis tank is made of highly transparent glass, with internal dimensions of 50*30*15cm and a volume of 22.5L. It meets the size requirements specified in the technical solution, and the tank wall thickness is 0.5cm.

[0165] The partition assembly is made of acrylic material, and its design and perforations are as follows: Figure 2As shown, the cross-section of the left and right side baffles (inlet and outlet baffles) along the water flow direction is a right-angled trapezoid, with the bottom hypotenuse forming a right-angled triangle with the tank body. A waste trough is located at the bottom of the outlet baffle to facilitate the removal of fish waste using hydraulic and gravitational forces. Because the upper part of the baffle is thicker than the lower part, contaminants tend to flow in from the lower part rather than the upper part. To ensure homogeneous water intake, only the upper half of the inlet and outlet baffles is perforated. The contaminated area measures 30*30*15cm, the camera is 40cm from the 30*30cm bottom surface, the baffle height is designed to be 15cm, and the lower slope height is 3cm. Using Formula 1, the difference in thickness between the upper and lower parts of the left and right side baffles is calculated to be 5.06cm. The lower thickness of the left and right side baffles is designed to be 0.5cm; therefore, the upper thickness is 5.56cm. The thickness difference of the front partition is 4.5cm, and the upper thickness is 5cm. The thickness difference of the rear partition is 5.63cm, and the upper thickness is 6.13cm, resulting in the partition assembly and cylinder design.

[0166] The internal circulation filter and the pollutant dispersion device are placed in the outlet and inlet water areas, respectively. The pollutant dispersion device includes an aeration component, a sewage inlet pipe, and a circulation filter outlet pipe. The hydraulic flow during their operation accelerates the homogenization of the water and the removal of excrement. A heating rod is additionally installed in the inlet water area to stabilize the water temperature for zebrafish farming.

[0167] The internal circulation filter is a modified miniature submersible pump with a head of 1.4m and a flow rate of 1000L / h. The outlet is vertically upward. An acrylic microporous plate is installed on the pump-water contact surface to filter large impurities. Aquaculture-specific bio-cotton is placed outside the plate to absorb and filter fish excrement. The plate and bio-cotton face the sidewall of the outlet area and are secured with acrylic clips. A food-grade silicone tube connects to the submersible pump outlet, with the other end connected to the inlet area. An opening is made 2cm from the inlet opening, into which a slanted PVC pipe (0.2cm inner diameter) is inserted, with the slant facing the proximal end. The PVC pipe connects to a food-grade silicone hose to the air, and an air volume regulating valve is installed to adjust the aeration rate. The circulation water pipe is secured with clips, ensuring the pipe opening is vertically downward.

[0168] Comparative Example 1

[0169] Using the quantitative evaluation method for behavioral parameters described in Test Example 1, both the conventional partition and the improved partition described in Example 1 were tested.

[0170] The standard partition is a cuboid with dimensions of 22*25*0.5cm. The 22*0.5cm side is flush against the bottom of the tank, secured with acrylic clips and BPA-free suction cups. The 22*25cm side is perpendicular to the bottom of the tank. The other auxiliary devices, besides the partition, are the same as in the fish behavior analysis tank of Example 1. Behavioral analysis is performed using Viewpoint's 2D behavior analysis system. Since this system distinguishes between living and non-living things based on light transmittance, tank wall joints, opaque areas, and water surface edges are all identified as living organisms. The selected image area is only the bottom area of ​​the tank where zebrafish can move. The experimental areas enclosed by the two partition assemblies were selected in the above manner, and movement time parameters were tested separately. The recording frequency was once per minute; therefore, time less than 60 seconds was considered unrecorded.

[0171] like Figure 6 As shown, the unrecorded time for the conventional partition was 3.41% ± 5.34% (2.04 ± 3.20 s / min). Figure 7 As shown, the unrecorded time of the improved baffle was 1.57% ± 2.64% (0.94 ± 1.59 s / min), which was 53.92% shorter than that of the conventional baffle. In this comparative example, the pre-filled water in the tank was pure water, so there were fewer missing tracks (wall-hugging, wall-colliding swimming) in the zebrafish, and most of the movement was due to cruising. The continuous cruising state meant that the zebrafish stayed in the same position less, so the improvement level was relatively low. In previous experiments, some pollutants (such as phenol) enhanced the escape behavior of zebrafish. The zebrafish would swim against the tank wall and baffle at a high frequency and for a long time, trying to escape the high concentration exposure area. In this case, the baffle described in Example 1 would greatly reduce the missing movement tracks.

[0172] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A fish behavior analysis tank based on improved camera technology, characterized in that, It includes a cylinder and a baffle assembly. The baffle assembly is located inside the cylinder. The inner wall of the baffle assembly is designed parallel to the camera optical path. The baffle assembly is composed of multiple baffles with gradually varying thicknesses. The internal space of the baffle assembly is the experimental area. The thickness of the baffles gradually decreases along the camera optical path. The baffle assembly includes a left baffle and a right baffle. The inner surfaces of the left baffle and the right baffle are trapezoidal in cross-section along the water flow direction. The bottom and side surfaces of the left baffle and the right baffle are adapted to fit the bottom wall of the cylinder. The bottom of the left baffle and the right baffle are provided with a manure trough. The upper middle part of the left baffle and the right baffle are provided with multiple evenly distributed inlet and outlet water passages. When the camera optical path is vertical, the partition assembly also includes a front partition and a rear partition, which are tightly fitted to the front and rear side walls of the cylinder, respectively. When the camera optical path is horizontal, the partition assembly also includes a bottom partition and a top partition; The formula for calculating the thickness of the partition is: (1), where, This indicates the thickness difference between the end of the partition closest to the camera and the end furthest from the camera. This indicates the distance between the camera and the cylinder wall at the end furthest from the camera. The height of the partition indicating the direction of the camera's optical path. This indicates the distance from the camera end of two relatively opposite partitions; The inner surface of the partition assembly is generally frustum-shaped.

2. The fish behavior analysis tank based on improved camera technology according to claim 1, characterized in that, When the camera light path is vertical, the partition assembly is provided with a top cover to prevent fish from escaping the experimental area.

3. The fish behavior analysis tank based on improved camera technology according to claim 2, characterized in that, When the camera light path is horizontal, the bottom partition is the bottom wall of the cylinder.

4. The fish behavior analysis tank based on improved camera technology according to claim 1, characterized in that, It includes an inlet zone and an outlet zone. The outlet zone is equipped with an internal circulation filter, and the inlet zone is equipped with an aeration device and a wastewater dispersion system.

5. The fish behavior analysis tank based on improved camera technology according to claim 4, characterized in that, The wastewater dispersion system includes a pollutant inlet pipe and a vertically downward-arranged circulating water pipe and aeration components. The pollutant inlet pipe and the circulating water pipe are closely fitted together, and the outlet of the pollutant inlet pipe is higher than the outlet of the circulating water pipe.

6. The fish behavior analysis tank based on improved camera technology according to claim 5, characterized in that, The cylinder body is made of transparent glass or transparent plastic material, and the partition and top cover are both made of transparent plastic material.

7. The fish behavior analysis tank based on improved camera technology according to claim 6, characterized in that, The plastic is acrylic plastic without any added endocrine disruptors.

8. The fish behavior analysis tank based on improved camera technology according to claim 7, characterized in that, The volume of the cylinder is not less than 10L, and the length, width and height of the cylinder do not exceed 50cm.

9. A method for evaluating behavioral parameters of a fish behavior analysis tank based on improved camera technology according to any one of claims 1-8, characterized in that, This is achieved by adding an auxiliary camera perpendicular to the analysis camera to the 2D behavior analysis system; I. Analyze the camera shooting vertically and assist the camera shooting horizontally; Quantitatively assess behavioral parameters using a fish behavior analysis tank with the camera beam in a vertical direction, including the following steps: A1. Fix the vertical analysis camera directly above the cylinder and ensure that the camera's shooting center is located on the vertical line of the center of the experimental area. A2. Fix the horizontal auxiliary camera directly in front of the cylinder and ensure that the shooting center of the auxiliary camera is located on the horizontal center line of the experimental area. A3. Record fish behavior videos in both vertical and horizontal shooting directions and perform trajectory recognition and output behavior parameters; Fish in the Frame and the The actual horizontal movement distance of the frame is : In the formula, This indicates the thickness difference between the top and bottom of the left or right partition. This indicates the distance between the analysis camera and the bottom wall of the cylinder. The height of the partition indicates the direction of the camera's optical path. This indicates the distance between the bottom ends of the left and right partitions. Indicates the first Frame to the The motion distance of the fish body output in the video image, i.e., the analysis of the distance between the camera and the first frame. Frame and the Connect the positions of the frames and extend the lines to the bottom wall of the cylinder. The line segment formed by the two intersections with the bottom wall of the cylinder is... value, This represents the length of the line connecting the starting and ending points of the actual movement trajectory projected onto the bottom wall of the tank, i.e., the actual horizontal distance the fish moves. and The output of the auxiliary camera is the first Frame and the The height of the fish's body in the frame; If the camera frame rate is 30 frames per second, then the horizontal distance the fish moves per second is: (3), where, For the first The total horizontal distance traveled by the fish per second; II. Analyze the camera shooting horizontally and the auxiliary camera shooting vertically; Using a fish behavior analysis tank with the camera optical path horizontal, behavioral parameters are quantitatively evaluated. The analysis targets the behavioral parameters when the fish rises or sinks. These behavioral parameters include rising or sinking speed, vertical movement distance, dwell time in the upper region, dwell time in the lower region, and swimming height. The analysis includes the following steps: B1. Fix the horizontal analysis camera directly in front of the cylinder and ensure that the camera's shooting center is located on the horizontal center line of the experimental area. B2. Fix the vertical auxiliary camera directly above the cylinder and ensure that the shooting center of the auxiliary camera is located on the vertical line of the center of the experimental area. B3. Record fish behavior videos in both vertical and horizontal shooting directions and perform trajectory recognition and output behavior parameters; The vertically downward auxiliary camera records the first The vertical distance between the fish body and the tank wall near the analysis camera. The horizontal analysis camera recorded the first The height of the fish body from the bottom partition in the image Calculate the first according to formula (4) The actual swimming height of the frame fish from the bottom partition : (4), where, To analyze the distance between the camera and the cylinder wall far from the camera, The difference between the cylinder sidewalls that are closer to the analysis camera and those that are farther away from the analysis camera is the distance between the front and rear sidewalls of the cylinder. Then the first Frame and the The distance between frames that float or sink: (5), where, and They represent the first Frame and the The actual swimming height of the fish from the bottom partition; No. Seconds to the Average speed per second and speed of movement for: （6）； （7）； In the formula, Indicates the first Seconds to the The average velocity per second; if the average velocity is positive, it indicates that the velocity is positive in the 1st second. Seconds to the Fish that swim in the upper part of the water tend to rise to the surface, while those that swim in the lower part tend to sink to the surface. Indicates the first Seconds to the The movement rate per second indicates the activity level of fish in the vertical direction. The larger the size, the more active the movement in the vertical direction; conversely, the smaller the size, the less active the movement. Indicates time interval, This represents the frame rate of the camera used.

10. A method for evaluating behavioral parameters of a fish behavior analysis tank based on improved camera technology according to any one of claims 1-8, characterized in that, This is achieved through a 3D behavior analysis system. The fish behavior analysis tank simultaneously meets the requirements of a fish behavior analysis tank when the camera light path is horizontal and when the camera light path is vertical. The fish behavior analysis tank does not need to be equipped with a top partition with varying thickness, and both the left and right partitions gradually become thinner in the direction of the vertical camera light path. The first analysis camera and the second analysis camera are set in the vertical and horizontal directions respectively. The coordinates of the 3D space of each frame are corrected according to formulas (8) to (13). The trajectory is depicted and the 3D space distribution is analyzed based on the corrected 3D coordinates of each frame image. Fish in the Frame and the The actual horizontal movement distance of the frame is : In the formula, This indicates the thickness difference between the top and bottom of the left or right partition. This indicates the distance between the first analysis camera and the bottom wall of the cylinder. The height of the partition indicates the direction of the camera's optical path for the first analysis camera. This indicates the distance between the bottom ends of the left and right partitions. Indicates the first Frame to the The motion distance of the fish body output in the video image, i.e., the distance between the first camera and the second camera. Frame and the Connect the positions of the frames and extend the lines to the horizontal plane at the bottom of the cylinder. The line segment formed by the two intersections with the horizontal plane at the bottom of the cylinder is the [frame name]. value, This represents the length of the line connecting the starting and ending points of the actual movement trajectory projected onto the bottom partition, i.e., the actual horizontal distance the fish moves. and The output of the second analysis camera is respectively the first Frame and the The height of the fish's body in the frame; If the frame rate of the first analysis camera is 30 frames / s, then the horizontal distance the fish moves per second is: (9), where, For the first The total horizontal distance traveled by the fish per second; No. The actual swimming height of the frame fish from the bottom partition : (10), where, This indicates the distance between the second analysis camera and the cylinder wall furthest from the second analysis camera. This indicates the distance difference between the cylinder sidewall closest to the second analysis camera and the cylinder sidewall furthest from the second analysis camera, i.e., the distance between the front and rear sidewalls of the cylinder. This indicates the first analysis of the camera's recording of the first... The vertical distance between the fish body and the tank wall on the side closest to the second analysis camera; Then the first Frame and the The distance between frames that float or sink: (11), where, and They represent the first Frame and the The actual swimming height of the fish from the bottom partition; No. Seconds to the Average speed per second and speed of movement for: （12）； （13）； In the formula, Indicates the first Seconds to the The average velocity per second; if the average velocity is positive, it indicates that the velocity is positive in the 1st second. Seconds to the Fish that swim in the upper part of the water tend to rise to the surface, while those that swim in the lower part tend to sink to the surface. Indicates the first Seconds to the The movement rate per second indicates the activity level of fish in the vertical direction. The larger the size, the more active the movement in the vertical direction; conversely, the smaller the size, the less active the movement. Indicates time interval, This represents the frame rate of the camera used.

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