Research About Intra And Inter Frame Coding Algorithms Based On H.264/AVC

In the past about ten years, a series of international video coding standards are developed and widely used in a variety of domains. Some standards for real-time telecommunication applications have been established by ITU-T, including H.261, H.263, H.263+, H.263++. Others for video storage, broadcast and stream application by ISO/IEC, such as MPEG-1/2/4.H.264/AVC is the newest standard approved by the ITU-T and ISO/IEC organizations, which represents a number of advances in video coding technology and becomes the newest international video coding standard because of both high coding efficiency and network friendliness.It can provide both objective and subjective image quality superior to existing standards. The main goals of this standardization are to develop a simple and straightforward video coding design with enhanced compression performance. Compared to MPEG-4 advanced simple profile, up to 50% of bit-rate reduction can be achieved.Some new techniques, such as spatial prediction in intra coding, adaptive block size motion compensation with small block sizes, Quarter-pel accurate motion compensation, 4x4 integer transformation, synchronization/switching pictures, multiples reference pictures and context adaptive binary arithmetic coding (CABAC), are used in this standard.With the use of these techniques, both compression efficiency and encoding quality are greatly improved. The testing results show that H.264 can greatly outperform existing video coding standards in PSNR, visual quality and compression efficiency.The new features of H.264/AVC increase not only the complexity of coding basic modules, but also the one of algorithms by times. That makes it very difficult for practical applications such as in real time video communication application or in some embedded system. So major works are as follows:First, in order to solve the problem that there are many prediction modes, the complexity of computation and which can't predict pixels located at the boundary of moving objects accurately in H.264/AVC intra prediction, an intra prediction algorithm is presented. The test result indicates that the adjacent pixels-based intra prediction algorithm can improve intra coding efficiency remarkably.Second, H.264/AVC uses multi-reference frames to enhance the coding efficiency. the quantity of increased computation is linearly proportional to the number of reference frames. On the study of the multi-macro-block motion estimation of H.264 standard, a low-complexity and fast multi-frame selection method is proposed. The experimental results show that the speed of the proposed method is over two times faster than that of the original scheme adopted in JVT reference software JM12.2 and JM10.2 while keeping the similar video quality and bit-rate.