Abstract: H.264 video coding standard is more efficiency and stability than the original coding substantially,but its computational complexity is also increased significantly.Reducing the complexity of encoding operations, improving real-time encoding, but no affecting the coding efficiency, it is necessary to make a study of the complexity of H.264. Intraprediction, inter-frame prediction, transform coding and entropy coding algorithm are improved to increase the compression ratio in H.264. This paper analyzes the above key technology in H.264, gives the complexity of modules in H.264 based on JM86. Testing results show that the complexity of H.264 encoding is mainly reflected in the inter prediction module. To speed up H.264 encoding speed, it is necessary to optimize this module.

Key words: video coding, H.264 video coding, coding complexity