Adaptive variable GOP length rate control algorithm for H.264

In order to solve the problem of video quality droping and rate control deviation is large when scene change is occur in H.264/AVC video encoding effectively,an adaptive variable GOP(Grop Of Picture) length rate control algorithm is put forward.First detect scene change with the average difference of gray value and stop current GOP in the place of scene changes,assigne unencoded frames in the current GOP average to the following two GOPs,then adjust rate allocation and quantization parameter for frames which scene chenge is appear.The simulation result show that: the proposed algorithm get some improvement compared to the original rate control algorithm in certain aspects,such as detect scene change effectively,the quality of subsequent video frame improved with an average of 0.64dB of peak signal-to-noise ratio(PSNR), the motion estimation time and total encoding time are decrease, the error of rate is small also, dropped an average of 2.71 kbps of rate deviation,new algorithm is well adaptability for video sequences with frequent scene changes.