Development Of Low Latency H.264 Video Encoding Algorithm Based On TMS320DM385

Video is an important way to get information,with the development of video technology,real-time encoding and decoding system based on embedded platform has played an increasingly important role in military,civil and other fields.H.264 is widely used in video encoding and decoding system because of its excellent efficiency and advanced industrial chain.The use of environmental diversification requires higher performance on latency of real-time encoding and decoding system,because of that low latency video encoding algorithm has a good engineering application value.This thesis develops a low latency H.264 video encoding algorithm based on TMS320DM385,which can effectively reduce the delay of each process in encoding and decoding system.One frame is divided into four slices for encoding,using pipeline parallel for the processes of encoding and decoding system,including video capturing and preprocessing,video encoding,bit stream transmission and video decoding.Make full use of every processor in these processes to reduce latency of the system.Take the only-P frame structure to reduce reordering latency and buffer latency,according to this structure develops a fixed direction intra-refresh algorithm to replace with I frame.A rate control algorithm is developed,by which adjusting the quantization parameters at the refresh cycle layer,frame layer and macroblock layer to further smooth the encoded bit stream for reducing buffer latency.Reducing the overall encoding and decoding system through these algorithms.The experiment results of the codec system shows that the low latency encoding algorithm has good video quality and has smooth encoded bit stream,the latency of 1080P30 video after encoding and decoding through this system is below 90ms,this thesis's algorithm has been applied in the Unmanned Aerial Vehicle(UVA)video transmission system of a research institute.