A new intra-frame rate control algorithm based on edge information for H.264

In this paper, we propose a new rate-quantization(R-Q) model and rate control algorithm for I-frames in H.264/AVC. The number of target bits for the first I frame is corrected based on pre-encoding of the first two frames, and the number of target bits of an ordinary I frame is determined by the relation among the number of bits generated for I frame and P frames of the recently encoded GOP. The Qstep is obtained according to the R-Q model which takes the frame complexity and buffer status into consideration. Experimental results show that the proposed algorithm can increase the average PSNR (peak signal-to-noise ratio) of reconstructed video by 0.96 dB for QCIF sequences and 0.46dB for CIF sequences. At the same time, some skipped frames are avoided.