基于单摄像机视频的鱼类三维自动跟踪方法初探

为提高鱼类行为学数据的提取效率, 实验提出了一种基于单摄像机的鱼类三维观测方法, 将防水镜面安装在实验用鱼缸上方, 模拟一台由上向下拍摄的摄像机, 实现了单摄像机三维成像。同时运用多目标跟踪的IMMJPDA(interacting multiple model joint probabilistic data association)算法, 实现了鱼类运动的三维实时自动跟踪, 并通过摄像机倾斜矫正和摄像机标定提高了测量精度。通过对6条红鼻剪刀鱼的跟踪, 实验结果显示: 本方法可正确区分、提取和跟踪鱼群个体以及它们的镜像, 自动输出鱼的三维坐标、实时速度、方向等参数, 并生成完整的鱼类行为三维轨迹图。     

基于计算机视觉技术的水产养殖中鱼类行为识别与量化研究进展

鱼类行为与水体环境密切相关,是鱼类生活状况的直接体现,可以通过分析鱼类行为进行更为精准的养殖管理和操作。计算机视觉技术为鱼类行为识别和量化提供了一种非入侵式且稳定性较好的方法,已逐渐广泛用于鱼类行为研究。本文介绍了计算机视觉技术的技术流程,包括图像采集、预处理、运动目标检测与跟踪,并对各个流程进行分类;综述了计算机视觉技术在鱼类游泳、摄食和体色变化等行为识别、量化研究的现状;分析了计算机视觉技术在鱼类行为识别、量化方面的难点及存在的问题,以期为计算机视觉技术在水产养殖监测领域的发展提供参考依据。     

基于线性调频(LFM)信号的单体鱼类目标回波识别与性能分析

在估计鱼类目标强度时,需要选择单体的回波信号进行计算.窄带信号下回波的相位标准差是单体检测的关键指标,但对于宽带信号相邻两点的相位差是时变的,无法将回波相位标准差作为单体信号的判定依据.本研究对线性调频宽带信号下的单体识别方法和性能进行了分析和仿真,并对该方法在消声水池内进行了测试和验证.结果显示:相比窄带信号,宽带信...     

基于图像特征的模板匹配成鱼多目标识别算法研究与程序设计

为解决渔业养殖及转运自动计数要求,提出一种基于机器视觉的鱼类识别算法设计与程序编制,以证明使用数字图像识别分类技术的尺度不变特征变换SIFT及加速稳健特征SURF算法等可有效地检测与标注鱼类图像特征点。采用快速近邻匹配FLANN匹配算法测试了基于图像特征的鱼类旋转和泛化目标检测,得出SURF特征对个体检测效果好、SIFT特征对泛化目标检测效果优的结果。考察FLANN图像匹配碎片化特性、结合图像信息区域聚集实际、借鉴模板检测方法,设计了图像分割扫描及特征匹配的模板检测算法,并使用最大稳定极值区域MSER方法对识别结果进行冗余排除,达到能正确识别多目标鱼类的算法预设目标。研究发现,该算法及软件能成功识别图片中的多个鱼类目标,测试效果好,有较强的实用意义。     

Video multitracking of fish behaviour: a synthesis and future perspectives

With the development of digital imaging techniques over the last decade, there are now new opportunities to study complex behavioural patterns in fish (e.g. schooling behaviour) and to track a very large number of individuals. These new technologies and methods provide valuable information to fundamental and applied science disciplines such as ethology, animal sociology, animal psychology, veterinary sciences, animal welfare sciences, statistical physics, pharmacology as well as neuro‐ and ecotoxicology. This paper presents a review of fish video multitracking techniques. It describes the possibilities of tracking individuals and groups at different scales, but also outlines the advantages and limitations of the detection methods. The problem of occlusions, during which errors of individual identifications are very frequent, is underlined. This paper summarizes different approaches to improving the quality of individual identification, notably by the development of three‐dimensional tracking, image analysis and probabilistic applications. Finally, implications for fish research and future directions are presented.     

鱼类标本及标本馆场景三维演示系统的研发

鱼类标本作为重要的科研资源在分类学、渔业资源学等领域中一直发挥着重要作用,通常鱼类标本经甲醛稀释液保存后存在易变形、褪色等不足,难以长期保存,同时受标本存放地限制参观访问量相对有限。为此开展了鱼类三维标本馆的构建,采用Strata Foto3D对鱼类标本图像进行遮罩、建立线框模式与增加表面纹理等处理;利用Strata Live3D完成三维鱼标本灯光、测量尺寸、背景图案、投影等效果的表达,并实现鱼类三维模型原色标本的网络发布;采用ASP技术完成了标本信息数据库的动态调用,实现标本生物学信息的文本展示。采用AutoCAD平面规划功能及3dsMax三维制作功能构建了标本馆三维虚拟空间,完成三维标本馆与单个鱼类标本模型的汇总整合;系统以Unity3D为开发平台,实现三维标本馆场景的虚拟漫游及网络人机交互功能。     

中国鱼粉鱼油来源及利用

鱼粉鱼油是渔业生产的重要原料,连接着海洋捕捞业与养殖业,是现阶段渔业转型工作的一个重要部分。中国自2000年以后鱼粉鱼油使用量在每年160×104 t左右,达到一个相对稳定的水平。通过梳理近10年中国鱼粉鱼油生产原料、产量和消耗情况,分析了中国鱼粉鱼油利用现状,提出了健全渔业捕捞相关法律法规、推动鱼粉行业绿色转型、加大水产动物营养生理与饲料的科研力度等方面的建议。     

Infrared reflection system for indoor 3D tracking of fish

Many fish rearing infrastructures are already equipped with human-operated camera systems for fish behavior monitoring, e.g. for stopping the feeding system when the fish is satiated or for monitoring of fish behavior abnormalities caused by poor water quality or diseases. The novel infrared reflection (IREF) system for indoor 3D tracking of fish demonstrated in the current study allows for automation of fish behavior monitoring, reducing the system running costs by eliminating the need for continuous human monitoring and increasing the behavioral analysis accuracy by excluding the human subjectivity factor.The operating principle of this system is based on the effect of strong absorption of near infrared (NIR) range light by water, thus allowing estimation of fish distance based on the corresponding fish object brightness on the camera image. The use of NIR illuminator as a part of the IREF system allows fish behavior monitoring in the dark so as not to affect fish circadian rhythm. A system evaluation under aquaculture facility conditions with Atlantic salmon (Salmo salar) using flow-through water in tanks, showed the mean depth estimation error was equal to 5.3 ± 4.0 (SD) cm. The physiological variations among conspecific individual fish introduced the mean depth estimation error of 1.6 ± 1.3 (SD) cm. The advantages of the IREF system over well-known stereo vision systems are lower hardware cost and less computationally intensive 3D coordinates estimation algorithm, while the disadvantage is lower accuracy that is nevertheless acceptable for most applications of aquaculture fish monitoring.     

深水网箱多波束水声鱼群状态监测仪的改进设计

针对离岸深水网箱养殖的鱼群安全问题,采用多波束水声技术监测鱼群状态的方法.结合信号处理技术、通用分组无线业务(GPRS)无线传输技术及串口通信技术,开发了一套多波束水声鱼群状态监测仪.监测仪完成1次网箱扫描只需5s;实现了监测数据的即采即发功能,提高了系统的实时性;改进了电路结构,降低了系统复杂度,减小了系统体积,降低...     

Evaluation of external fish injury caused by hydropower plants based on a novel field‐based protocol

Knowledge on the extent and mechanisms of fish damage caused by hydropower facilities is important for their ecological improvement. Herein, a novel field‐based fish injury assessment protocol is proposed that includes vitality and four general health criteria, as well as nine lethal and sub‐lethal injury types across 18 body parts. The protocol was validated using 3,087 specimens from four species of hatchery‐reared fish, as well as 2,262 specimens from 32 species of wild fish. The protocol allowed a detailed and systematic evaluation of different fish injury types in the field. Injuries related to handling and to contact with different parts of the hydropower structure could be distinguished applying multivariate statistics. This approach allows quantification and comparison of fish injuries across sites, and can help to identify the technologies and operational procedures that minimise damage to fish. It may also be useful to assess fish health in other contexts including aquaculture.