基于小波的视频压缩算法在视频会议系统中的应用

【作者】 王拯洲；

【导师】 康慕宁；

【作者基本信息】 西北工业大学 ， 计算机科学与技术， 2007， 硕士

【摘要】 传统的视频压缩算法都是基于分块的离散余弦变换编码方法，由于其良好的去相关性与能量压缩特性，已使其成为现有大多数图像／视频压缩国际标准的核心技术。但是基于DCT变换的压缩图像不可避免地会出现块效应和飞蚊噪声。所以如何能提供关于质量、分辨率、信噪比等多种可扩展编码结构，实现多分辨率编码、嵌入式编码，从而能在无线移动环境向用户提供个性化的服务，是目前重点研究的课题。基于小波编码的视频压缩算法，能够满足现代应用所需要的许多特征，如多分辨率编码、多层质量控制、嵌入式码流等，均能与小波图像编码结构非常自然地融合在一起，所以小波变换编码是变换编码新的、重要的发展方向。 论文在研究小波变换理论和静止图像压缩编码方法的基础上，对嵌入式零树小波EZW算法进行改进。在分析空间域、变换域、三维小波运动补偿的基础上，研究了小波域中的运动补偿技术，并提出了基于运动区域改进的多分辨率运动估计算法。 论文以小波变换为理论依据，采用改进的视频压缩算法进行视频压缩，通过对压缩比和数据的失真率和H.263压缩技术进行比较，达到更高的压缩比和更小的失真率，并对视频会议系统的功能进行完善，解决音频视频同步以及非固定IP支持等问题，使得视频会议系统具有更强大的功能，并成为一个完全仿真的视频会议系统。更多还原

【Abstract】 Traditional Video compress are Discrete Cosine Transform encode based on detach block, which has good irrelated and energy compress performance, has become the most Image/Video compress international standard of kernel technology. However, block effect and flying mosquito yawp based on DCT picture is inevitable. So how to provide many extended encode struct , for instance, quality,resolution is the topic that many project teams studies, which could realize multi resolution encode ,embedded encode and could provide personal service to user in wireless environment. The Video compress based on Wavelet could need the most of necessary character of modern application, such as multi resolution encode , multilayer quality control, embedded code stream, which could be mixed together entirely. Wavelet transform is the newest and important develop direction of transform encode.This paper study deeply the wavelet transform theory and statistical image encode arithmetic ,and improve on embedded zerotree wavelet arithmetic. Based on spatial domain, transforming field, three dimension wavelet ,this paper study wavelet field motion compensation technology and put forward an improved Video encode arithmetic of wavelet field motion compensation based on motion field.Based on wavelet transform theory ,the paper uses the video encode arithmetic which is provided in the paper to encode the video data, comparing compress rate and loss rate of data with H.263 compress technology, we found higher compress rate and less loss rate. To improve the function of Video Meeting System, produce the Synchronization of Audio and Video and support the dynamic IP Address. Video Meeting System have more powerful function and become a full real Video Meeting System.更多还原