Transform And Quantization Process Optimization. H.264 Standard

The technique of digital video is applied to communication, computer broadcast TV etc. field. For example, video meeting, visual phone and digital TV all used it. The key technology among these applications is video compressing, which brings many coding standards out. H.264/AVC is newest video coding standard of the ITU-T Video Coding Experts Group (VCEG) and the ISO/IEC Moving Picture Experts Group (MPEG), which greatly enhance compressing performance and provide a "network-friendly" video representation addressing "conversational" ( video telephony) and "non -conversational" (storage, broadcast, or streaming) applications.But the enhancement of compressing is based on rapid increasing of compute complexity, which has been the main hindrance of massive application. Thus, the coding couldn't be the best in some particular condition. In addition, H.264/AVC only carried a norm to the decoding which left some space for its optimizations. Based on present condition, this project did a great deal of researches to decrease its calculation complications and raise the efficiency of calculating.Firstly, introduced the researches about video coding Home and abroad and H.264/AVC standard. Based on the disadvantages and problems of coding software, combining the individual traits of model, we optimized the coder in three aspects. The three aspects are forecast in frame, integral DCT transfer and quantity. A new mode selection algorithm is presented. Coder soft ware is optimized by adopting new searching algorithm which the blocks whose quantized DCT coefficients are completely zero can be pre-determined. The guideline to pre-determine all-zero blocks of integral transfer is optimized. The experiment took the JM7.0 software model as the main source, carried on the simulated test, and made a contrast with the image vision quality, coding time and change of PSNR before optimizing and after it.The experiment proved that after the process of adopting new selection algorithm, searching algorithm, integral transfer and quantity, the complication of calculation is decreased greatly. This method advanced the coding efficiency of video compressing. Finally, this paper is presented summarizer and future prospects the H.264/AVC algorithm.