The MPEG-4 Network Video Encoder Based On Media Procesdor

With the fast development of modern information thechnology, video applications especially in the areas such as picture communication, video surveillance , stream media, digital TV, some devices are made basen media processor. TMS320DM642 is a new programmable high-performance multimedia processing DSP. This thesis proposed the real-time network video encoder based on TMS320DM642, which is applied in video surveillance and video communication.Firstly, The history of video surveillance and the architecture of TI C6000 are introduced . Then we supply three video encoder standards which is widely applied: H.263, MPEG-4 and H.264. Based on the characteristic of DM642 and the practically application requirement, we select MPEG-4 simple profile as our encoder arithmetic.Seondly, we propose some arithmatics in the texture encoder module and motion encoder model of the MPEG-4 encoder simple profile. these arithmatics in motion encoder are motion search,motion vector prediction, selection of encoder mode; these arithmatics in texture encoder are DC/AC prediction, quantisation and rescale, VLC encoder. And we apply the modification of these arithmatics for the implementation of MPEG-4 encoder based on DM642.Thirdly, we introduce some optimization methods based on the hardware characteristics of DM642 for the real-time requirements. At first, the architecture of DM642 and instruction system are gave, and the memory architecture of DM642 and pipeline methory are introduced. And then we propose some optimization methods, for example, the usage of EDMA to dispach data between out-chip memory and in-chip memory for the reduction of delay time of CPU; the optimazition configuration method of in-chip memory , that is to configure in-chip memory as memeory and L2 cache with some proportion, and putting the often-called functions and data sections in in-chip memory; to rewrite the often-called function with linear assembly language for full pipelined assembly instructions, so as to exert the parallelism of DM642; to adopt some compiler options; and so on. Through the usage of the optimization methods, we achieve the real-time MPEG-4 network encoder based on DM642.Lastly, we introduce the implement of the MPEG-4 network encoder system . It consists of three model: capture model,encoder model and network model. The network encoder system achieve real-time capture, encode and transfer, and last save bitstream to PC.