A Fast Rate-distortion Based Quantization Level Adjustment Algorithm For H.264

摘要

It is desired to obtain the best possible image quality subject a predefined bit rate in video coding. Focusing on improving quantization performance for signals in non-flat region, the ratedistortion based quantization level adjustment algorithm (RDQLA) was proposed in our former work. It can improve the coding performance efficiently. However, exhaustively searching the optimal quantization level is computationally expensive. In this paper, a fast RDQLA algorithm for H.264 is proposed to effectively choose the optimal quantization level without exhaustively searching. Experimental results show that the proposed fast RDQLA algorithm can drastically reduce the encoding time up to 40% with acceptable loss of coding efficiency.