Digital Audio And Video Compression Technology, Standards And Applied Research

With the development of digital Audio Video Coding technology, digital Audio Video Coding Standard is more and more important. During the course of postdoctoral research, we did some researches in following aspects:First, the history, the process of establishing, the application, and the Intellectual Property Rights Policy of international digital Audio Video Coding Standard are described in the paper. Especially, We mainly discuss AVS Standard, which is researched and developed by china themselves. This Intellectual Property Rights Policy of the Audio Video Coding Standard Working Group of China is very outstanding in that it overcomes the obstacles of the charge of Property Rights, which is confront with other digital Audio Video Coding Standards.Second, Some new algorithms of digital Audio Video coding technology is presented in this paper, such as start-code-emulation and transcoding technology. Start-code-emulation is an important part of digital Audio Video coding technology, which belongs to systems layer coding. The Start-code-emulation in the paper is an effective method for random accessing and for correcting the data. Besides, transcoding technology is discussed in the paper, which is emphasis on the issue of the noise adding in the course of transcoding from MPEG-2 to AVS. This paper first presents how to calculate the threshold of the PSNR of a program, and then presents a formula of calculating the PSNR of a program based on statistical concept.In addition, during the course of postdoctoral research, we developed the H.264 decoder and AVS encoder and decoder system. And the AVS encoder and decoder system can be accomplished the encoding, transmitting and receiving the video and audio data, in which encoding is non-real-time, while coding is real-time. And this project won the Technological Innovative prize in Shanghai International Industry Fair.