基于H.263+视频传输的误差恢复技术

论文提出了一种应用于H.263+视频传输的误差恢复方法,即基于H.263+视频编解码器的差错掩盖方法。在这种方法中,在编码器端通过重传出现差错的数据和发送帧内编码帧来限制误差的扩散和繁衍;在解码器端利用视频信号在空间域和时间域上的相关性对受损的数据进行误差掩盖。模拟结果表明,这种误差恢复方法能够使得在有噪音干扰信道上传输的图像质量获得明显改善。其可以应用于公共交换电话网(PSTN)、Internet等能够提供反馈信道的视频通信环境中。     

The linear programming approach to the Randić index

Let G(k, n) be the set of simple graphs (i.e. without multiple edges or loops) that have n vertices and the minimum degree of vertices is k. The Randi? index of a graph G is: , where δ_u is the degree of vertex u and the summation extends over all edges (uv) of G. Using linear programming, we find the extremal graphs or give good bounds for this index when the number n_k of vertices of degree kis n?k+t, for 0tk and kn/2. We also prove that for n_kn?k, (kn/2) the minimum value of the Randi? index is attained for the graph .     

极低码率下运动图象的压缩

首先根据当前运动图象压缩的国际标准,讨论了极低码率下的编码问题,然后介绍了Ｍａｔｃｈｉｎｇ Ｐｕｒｓｕｉｔ在该领域中的应用,其具体过程是利用二维Ｇａｂｏｒ函数字典对帧间预测差值进行Ｍａｔｃｈｉｎｇ Ｐｕｒｓｕｉｔ＾（１）,这样能获得低码率下更高的压缩比和更好的效果,而且由于函数字典不是基于块的,因此消除了在低码率下ＤＣＴ变换的方块效应。此外,在进行帧间预测差值编码时,是从能量最集中的区域开始,逐渐     

基于IP网络的多媒体信息传输的研究

论文主要介绍了以视频信息为主的多媒体信息在IP网络中进行实时传送的纯软件实现方法,给出了图像与数据的采集、处理、传输及设备的远程控制的完整解决方案。     

H.323视频会议终端的软件实现

在对音视频协议和视频会议实际应用场景分析的基础上,采用新算法和新技术,在Intel PII333的PC机上用软件实现了视频会议终端的音视频实时编解码处理.实验结果表明该软件能同时完成15帧s、CIF格式的H.263视频编解码和G.711语音编解码,实现了以软件为核心的视频会议终端.     

一种新的视频编码的块运动估计算法

本文提出了一种连续判别的非线性预测搜索ＮＰＳＳＤ块运动估计算法,可以用于视频压缩的一些国际标准,如Ｈ．２６１,Ｈ．２６３,ＭＰＥＧ１,ＭＰＥＧ２,ＨＤＴＶ中。ＮＰＳＳＤ算法充分利用了序列图像的实际运动矢量与预测矢量之间的位移的空间分布特性－－中心偏置分布特性和时间上的相关特性,并在搜索过程中采用了中止判别和搜索判别,可以明显地减少运动搜索复杂度。仿真表明这种算法减少了搜索次数,提高了搜索效率,降低     

A Content-Based Search Algorithm for Motion Estimation

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Senolytic Therapy for Cerebral Ischemia-Reperfusion Injury

Ischemic stroke is one of the leading causes of death, and even timely treatment can result in severe disabilities. Reperfusion of the ischemic stroke region and restoration of the blood supply often lead to a series of cellular and biochemical consequences, including generation of reactive oxygen species (ROS), expression of inflammatory cytokines, inflammation, and cerebral cell damage, which is collectively called cerebral ischemia-reperfusion (IR) injury. Since ROS and inflammatory cytokines are involved in cerebral IR injury, injury could involve cellular senescence. Thus, we investigated whether senolytic therapy that eliminates senescent cells could be an effective treatment for cerebral IR injury. To determine whether IR induces neural cell senescence in vitro, astrocytes were subjected to oxygen-glucose deprivation/reoxygenation (OGD/R). OGD/R induced astrocyte senescence and senescent cells in OGD/R-injured astrocytes were effectively eliminated in vitro by ABT263, a senolytic agent. IR in rats with intraluminal middle cerebral artery occlusion induced cellular senescence in the ischemic region. The senescent cells in IR-injured rats were effectively eliminated by intravenous injections of ABT263. Importantly, ABT263 treatment significantly reduced the infarct volume and improved neurological function in behavioral tests. This study demonstrated, for the first time, that senolytic therapy has therapeutic potential for cerebral IR injury.     

H.263无线视频传输的关键技术改进

移动多媒体业务是当前移动数据通信的研究热点。视频信号处理需要大量的运算,要求较宽的传输带宽。目前移动网络上的视频传输存在着网络带宽有限、误码严重、终端处理能力较弱等问题。基于H.263提出了提高编码效率、增强抗干扰能力的编解码算法优化方案,有效地提高了运算效率,提升了解码视频的主客观质量。     

AXPE1280V视频信号处理器在视频编码中的应用

介绍了ＡＸＰＥ１２８０Ｖ视频信号处理器的结构和基于该处理器的应用方案。该方案支持基于视频数据块的并行处理,并提供多种数据格式的接口,从而可以实现多种视频信号处理的要求。