关键词: H.264, 帧内编码, 模式选择, BP神经网络

Abstract: H.264/AVC provides 17 modes for intra prediction，and the optimal mode is selected by Rate Distortion Optimization （RDO） with high coding complexity.Although most of the current algorithms of intra prediction mode decision can reduce coding complexity greatly，there still exists high computational complexity.A new fast intra prediction mode decision algorithm based on BP neural network is proposed.The algorithm firstly judges the mode of the macroblock as either Intra16×16 or Intra4×4 mode，using the training result of the BP neural network with lots of video sequence.Then the optimal mode is decided from 17 modes by Pan Feng’s method.Experimental results show that the proposed algorithm can efficiently reduce the computational complexity up to 75%～83% compared to JM86 and 30%～70% compared to Pan Feng’s method，and can maintain the coding performance （the reduction of PSNR is only 0.01 dB on average）.

Key words: H.264, intra prediction, mode decision, BP network