基于背景减与帧间差分结合的视频运动目标分割

提出一种视频运动目标分割的改进算法,算法混合使用背景减算法和帧间差分算法,充分利用了两种典型算法的优点,并改进了其缺陷,解决了背景减算法的背景合理更新及帧间差分算法分割不完整问题.实验结果表明：该算法简单,速度快,易于硬件实现.     

linux环境下基于usb摄像头的图片采集与分析

video4linux提供了一整套linux环境下操纵视频设备的函数接口,首先通过对video4linux函数的调用成功实现了两种方式(内存映射(mmap)和直接读取(read))下摄像头数据的读取;然后对读取到内存缓冲区中的RGB数据流进行分析,实现了同时对两种特定颜色(红、绿、蓝等)的识别,并给出相应色块的端点坐标;最后通过对特定颜色箭头的端点分析,识别了箭头指向的角度;为了便于调试程序和验证结果,分析完成后把缓冲区中的RGB流保存为BMP文件。     

Preparative Separation of Sulfur-Containing Diketopiperazines from Marine Fungus Cladosporium sp. Using High-Speed Counter-Current Chromatography in Stepwise Elution Mode

High-speed counter-current chromatography (HSCCC) was successively applied to the separation of three sulfur-containing diketopiperazines (DKPs) (including two new compounds cladosporin A (1) and cladosporin B (3), and a known compound haematocin (2)) from a marine fungus Cladosporium sp. The two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water at (1:1:1:1, v/v) and (2:1:2:1, v/v), in stepwise elution mode, was used for HSCCC. The preparative HSCCC separation was performed on 300 mg of crude sample yielding 26.7 mg of compound 3 at a purity of over 95%, 53.6 mg of a mixture of compounds 1 and 2, which was further separated by preparative-HPLC yielding 14.3 mg of compound 1 and 25.4 mg of compound 2 each at a purity of over 95%. Their structures were established by spectroscopic methods. The sulfur-containing DKPs suppressed the proliferation of hepatocellular carcinoma cell line HepG2. The present work represents the first application of HSCCC in the efficient preparation of marine fungal natural products.     

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.     

How long should we ignore imperfect detection of species in the marine environment when modelling their distribution?

The application of the ‘ecosystem approach’ to marine conservation management demands knowledge of the distribution patterns of the target species or communities. This information is commonly obtained from species distribution models (SDMs). This article explores an important but rarely acknowledged assumption in these models: almost all species may be present, but simply not detected by the particular survey method. However, nearly all of these SDM approaches neglect this important characteristic. This leads to the violation of a fundamental assumption of these models, which presuppose the detection of a species is equal to one (i.e. at each survey locality, a species is perfectly detected). In this article, the concept of imperfect detection is discussed, how it potentially influences the prediction of species' distributions is examined, and some statistical methods that could be used to incorporate the detection probability of species in estimates of their distribution are suggested. The approaches discussed here could improve the collection and interpretation of marine biological survey data and provide a coherent way to incorporate detection probability estimates in the modelling of species distributions. This will ultimately lead to an unbiased and more rigorous understanding of the distribution of species in the marine environment.     

基于3G＋VSaaS技术的深水网箱养殖远程视频监控系统

为提高深水网箱养殖过程监控的准确性与实时性,设计了一种深水网箱养殖远程无线视频监控系统。该系统利用3G无线网络技术实现深水网箱养殖网络化的本地或远程的实时视频监控,采用3G＋VSaaS模式,通过网络摄像头采集深水网箱现场数据,通过无线网络传输、发布和共享,并同时实现执行机构的反馈控制。文章介绍了工作原理与系统总体构架,阐述了系统硬件部分的选取设计原则,并分析了系统工作的关键技术。构建起深水网箱全方位远程监控体系,可实现深水网箱养殖信息化管理,提高养殖生产效率及风险防范能力。     

“微视频+农业生产技术服务”模式的应用探究

目前，我国正处于从传统农业向现代农业转型的关键时期，“微视频+农业生产技术服务”这一模式的应用可以打破时空限制，进一步拉近与农技人员的距离，从而使农业生产技术服务效率有较大提高。通过种植作物标准化生产技术视频的拍摄，将规范拍摄剪辑成操作微视频和图片，集成到产销服务平台上，依据生产者的种植状态，定制化的推送相对应的操作视频等技术指导，有效提高了农场的生产管理效率和标准化水平，使农业技术人员可以随时随地、无需付费进行标准化生产技术的学习。