用Authorware制作多媒体课件时影音素材的处理

本文主要研究了在CAI软件的设计制作过程中，音频和视频信息的处理方法，主要有：根据WAV声音文件的特性，在保证声音文件不失真的前提下，完成改变文件大小，以节省存储空间；研究了声音文件的不同存储格式和播放原理，在Authorware中实现多层次声音的播放，探讨了Activex控件技术，利用其解决了不同格式的MPEG视频文件在Authorware中的播放问题，还讨论了使用Movie Control播放视频的方法。     

Low cost pre-stored video transmission across networks

This paper proposes a simple, practical and low-cost dynamic segmentation and bandwidth allocation scheme, called middle point, to transmit pre-stored video from source to playback destination across networks. The proposed scheme is based on two concepts, playback tunnel and bandwidth tunnel, to determine the segmentation boundary and transmission bandwidth with the objective of reducing transmission cost while guaranteeing the playback buffer neither underflows nor overflows. The performance of the proposed scheme is evaluated by a set of real-life MPEG video traces and also compared with the well-known optimal smoothing scheme. The obtained results show that the proposed scheme can be easily implemented with low complexity and low transmission cost.     

Distinguishing video quality through differential matrices

Multicast multi-layered communications must implement efficient control algorithms to address undesirable network behaviors. This paper proposes two multi-metric algorithms for computing the rates of the video layers and improve the global video quality of a multicast session. In fact, we show that a single-metric approach may degrade some network parameters without obtaining any substantial improvements. Our first algorithm combines three metrics and a set of weights in such a way that one metric can be prioritized. This leads to an improved quality of multicast sessions, as we show through a number of experiments. In networks where the available resources are highly variable, however, the stability of the video quality is compromised if absolute values of the metrics are adopted. We then propose a second algorithm that uses the relative values of the metrics on a per-entry basis. Computation of the global quality of the multicast session is based on a differential matrix that stores the metrics for each receiver. This scheme takes into account the dynamics of the available resources and the heterogeneity of receivers. The great benefit of this approach is that the global video quality is always improved for every loop of the algorithm.     

数字电视视频记录的设计与实现

以Philips Pnx8320多媒体芯片为基础，浅析了视频记录3个主要部分：视频记录文件系统；视频记录管理和视频记录文件格式。通过对这3个部分的分析，做出了一些探索性的实现研究。     

一种基于M-JPEG的视频码流传输方案及其应用

针对现有的Internet通常不支持QoS的现象，提出了一种基于M－JPEG编码格式的自适应Internet视频码流传输方案，及其作为视频传输子系统在视频监控系统中的应用。     

三级监控系统的设计和实现

论文介绍了一套三级监控系统的设计与实现。该监控系统采用了三级分层树形结构,能够同时对多个监控点进行监控,适用于LAN、PSTN、ISDN等多种网络,传输全数字化的视频与音频信息。文章中对该系统的整体组成、硬件结构以及软件设计等方面都进行了较为详细的讨论。     

视频采集系统软件设计

该文介绍了Bt848卡的主要结构和工作原理,并详细描述了集成到可以实现上网和多媒体通信双重功能的IS-DN卡上的Bt848芯片驱动程序的实现,包括分配DMA内存区,分配视频缓冲区,以及视频数据在芯片和PC机内存之间的流动过程,并给出了具体的实现方法。     

基于对等网络的Intranet视频监控系统设计

剖析了对等网络技术的应用特点，并详细分析如何将对等网络技术应用在视频监控系统中，以及基于对等网络的视频监控系统的特点和应用中的问题。     

H.26L视频编码标准的特点及分析

继制定了H．261、H263、H．263 等视频编码标准以后，ITU—T又正在制定新的视频编码标准H．26L，目的是为了取得更好的图像压缩效果和更多的实用功能。该文介绍了H．26L视频编码标准的产生背景、技术特点，并对其进行了分析。     

WebCCTV系统的设计和实现

该文首先对传统CCTV系统和WebCCTV系统进行了比较。然后对WebCCTV系统的体系结构进行了设计,分析了其特点。最后对其关键技术进行了研究,并提出了适合于WebCCTV的解决方案。