H.264差错隐藏技术研究及改进+文献综述
本论文首先研究混合编码结构中的三大压缩编码方法，然后研究了差错隐藏的两类经典方法，即时域差错隐藏和空域差错隐藏。研究平台是H.264视频标准，利用开源编解码器JM进行算法的运行和研究。最后，针对JM中空域隐藏对边缘信息的局限性，本论文提出了一种基于边缘检测和区域划分的改进算法。实验表明，本文中的算法可以获得较高的PSNR以及较好的视觉感受。
关键词 差错隐藏；H.264；空域；边缘检测
毕业设计说明书（论文）外文摘要
Title The study and improvement of error concealment techniques
Abstract
With the widely use of mobile phones and the Internet, the transmission of multimedia information in network has become more and more popular. However, because of the channel disturbance, the signals received at the destination may have some lost or incorrect decoded. What's more, the compressed video signals are very sensitive, which leads to the propagation of the error. Error concealment makes use of the correctly received information to deal with the lost video content to satisfy the human visual feeling.
This paper firstly studies the three classic compressed encoding methods in the hybrid video coding schemes, then two kinds of error concealment methods, temporal and spatial concealment techniques are introduced.
The algorithms are studied based on the joint model (JM) of H.264 standard. Considering the limit of the spatial error concealment technique in JM, this paper proposed an algorithm based on edge detection and block partition. Compared with the error concealment feature implemented in the JM, this algorithm is able to achieve higher PSNR as well as better visual quality.
Keywords error concealment；H.264；spatial concealment；edge detection
目 次
1 绪论 1
1.1 课题背景及选题意义 1
1.2 视频编码标准 1
1.3 章节安排 4
2. 视频编码基本理论 5
2.1 预测编码 6
2.2 变换编码 10
2.3 熵编码 13
3 差错隐藏技术 14
3.1 视频差错隐藏技术 15
3.2 JM差错隐藏技术 18
3.3 评价标准 19
4 基于边缘检测的差错隐藏 21
4.1 算法原理 21
4.2 仿真结果 25
4.2 小结 27
结 论 28
致 谢 29
参 考 文 献 30
1 绪论
1.1 课题背景及选题意义
近年来，随着移动通信技术的迅猛发展，各种移动多媒体通信技术和新兴多媒体业务不断出现，如无线可视电话、移动流媒体系统以及无线视频监控等。视频压缩与通信技术已经成为当今信息科学与技术的研究热点，并取得了令人瞩目的成就。而由于信道带宽的限制，人们往往使用经过高效压缩的数据作为视频通讯的数据。现有的视频编码标准基本都采用基于运动补偿、变换编码和熵编码的框架，这些编码方法在降低多媒体信息冗余度的同时，也使得图像或视频对于差错异常敏感。往往一个比特的错误或者丢失都可能造成后续比特无法解码。