Implementation And Optimization Of MPEG-2 Transrating System On DSP Platform

As the development of video coding and communication techniques, digitized coding, transmission and processing of Broadcasting TV programs have been widely used in practice. Analog Broadcasting TV programs are predicted to be replaced by the digital gradually in the future. As we know, MPEG2, a famous mature video coding standard, has already been broadly employed in the field of Broadcasting TV network, and undoubtedly considered as the international standard for D1 video compression. However, due to the constraints caused by the limited bandwidth, new problems occur when high bit-rate streams or irregular streams are transmitted. Therefore, it would be a valuable work in the video transmission field to enable consumers receive more digital TV programs using the same bandwidth.This thesis is going to give a detailed introduction on the MPEG2 transrating system. The system analyzes the MPEG2 Transport stream first, extracts the elementary stream from it, recompress the elementary stream using the close loop transrating algorithm, and packets the recompressed elementary stream to construct the output Transport stream at the end.The work of extracting and packing the elementary stream, also called De-multiplex and Multiplex respectively, is performed in the MPEG2 System Layer. Different from video coding or decoding, transrating includes both De-multiplex and Multiplex. So the implementation of its system layer has its own particularity and flexibility. This thesis will give you a brief introduction on MPEG2 system layer, and then go on with the implementation of De-multiplex and Multiplex in the Transrating system, including processing specific program information and program clock reference.It should be mentioned that as to reduce the effect on the video quality, transrating algorithm usually has a high computation complexity, meanwhile, it also has to satisfy the rigorous real-time request. So optimization is a critical facility for transrating system's real-time processing. TI-DM642 DSP is used as the hardware platform of our system. Compared with general purpose CPU, DSP is more suitable for these real-time resource-consumption applications. Based on...