A Fast Quantization Level Adjustment Algorithm to the Signals Near Dead-Zone

Focusing on improving quantization performance for signals in non-flat region, the rate-distortion 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. By analyzing the coding mode of the macroblock, the proposed algorithm can 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 compared with RDQLA algorithm Moreover it outperforms H.264 at all rates.