Research On Bit Stream Syntax Restricted Video Coding Algorithm Optimization

With the incoming of information society, the demand of multimedia application increases greatly. As a result, video compression and coding attracts the researching focus of many experts, and one important researching issue is the optimization for video coding algorithm. That is, how to efficiently eliminate the redundancy in video sequences, and how to improve the coding efficiency and video quality as soon as possible.Optimization for video coding algorithm involves two categories according to if optimization will affect the syntax of the coded bit stream. One is the bitstream syntax restricted optimization, and the other is the bitstream syntax unrestricted optimization. The later one focus on optimization for video coding algorithm without considering the restriction of the syntax of coded bitstream. All kinds of optimization technology of video coding can be employed to improve the coding efficiency, and it was these technologies that resulted in the international video coding standards such as the H.26x and MPEG.Many video applications are based on a certain video coding standard. Within the framework of a certain standard, how to optimize the coding algorithm to improve the coding efficiency is very meaningful and important to save the storage capacity and the bandwidth to transmit the coded bitstream. Thus, we will mainly focus on the bitstream syntax restricted optimization for video coding algorithm in this paper. In fact, video coding optimization is a problem of rate distortion optimization. On the other hand, we may focus on video coding optimization considering the human visual system (HVS) characteristics because that the human eye is the ultimate judger of visual quality.First, the framework and structure of the hybrid video coding algorithm are introduced. The components whose implementation methods have not been forced in video coders, such as rate control, motion estimation and compensation, video sequence preprocessing etc, are introduced, and their influences on the coding efficiency of these components are analyzed. Then, the possibilities of video coding optimization are analyzed on the sequence, picture and macroblock (MB) levels respectively. Furthermore, the rate distortion optimization theory is introduced, and the relationship between the video coding and rate distortion optimization is analyzed in detail. The advantages and disadvantages of using rate distortion optimization theory on video coding optimization are discussed.Second, the importance of rate control algorithm on video coding optimization is analyzed. Several components within rate control algorithm such as bit allocation, adaptive quantization, Qp selection etc and their internal relationships as well as their influence on visual quality are...