Improvement on frame layer rate control scheme for H.264/AVC

This paper evaluated the linear interpolation, bit allocation on average and some other techniques used in H.264/AVC rate control algorithm. Then we proposed an improved algorithm to tackle the problems as the imprecise initial quantization-parameter (QP) calculation, the inaccurate bit allocation and so on. The proposed algorithm had the following features: a. The resign of the quantization algorithm in H.264/AVC resulted in an exponential predicted model; b. The QP of B frames were no longer using linear interpolation but using the self-adapting adjustment by the correction parameter ¿_B; c. Considered the complexities of I frames and allocated bit to them in the encoding process; d. The target bit allocation for each P frame was proportional to its complexity in the group of picture (GOP). Experimental results and analysis showed that the improved rate control algorithm had increased the average peak signal-to-noise ratio (PSNR) up to 0.41 dB on average and improved the quality of the reconstructed video obviously.