Performance and complexity joint optimization for H.264 video coding

This paper proposes a video coding optimization approach for those real-time visual communication applications with performance and complexity tradeoff based on the coming H.264 video coding standard, which has a very high performance with high coding complexity. In H.264, the better coding performance is achieved at the cost of complexity, and it is too complex to be applied widely. With the performance and complexity joint optimization method of this paper, the modules are optimized respectively in the order of their computation proportion. Adaptive hexagon-based search (AHBS) and memory motion compensation (MMC) are proposed for encoder and decoder. AHBS is about 40 times faster than full search, and a little faster than diamond search. However AHBS achieves the best coding performance: 0.4dB improvement in low motion sequences, and 0.2dB improvement in high motion sequences compared with full search. The decoding process is accelerated up to 5 times totally with proposed MMC and other optimized techniques. Therefore the efficiency of codec system is improved greatly. Optimized video codec can be used in uni-casting and broadcasting streaming applications with limited computation resource in those embedded movable devices.