基于场景切换的B帧量化参数分配方法

H.264/SVC实现了对基本层码率控制，但对于视频序列中场景切换并没有有效的检测，也没有考虑到场景切换对视频编码质量的影响.本文结合H.264/SVC特有的分层B帧预测金子塔编码结构，首先提出一种改进的基于图像复杂度的实时场景切换检测算法，结合场景切换的类型，再对存在场景切换的GOP编码单元中时间分级的高层B帧量化参数进行修改.实验结果表明在不产生信道码率突变的前提下，明显改善了场景切换处的视频质量.

New Method for Quantization Parameter Assignment for Hierarchical B Pictures Based on Scene Change

H. 264/SVC realizes the basic level rate control, but does not detect scene change in video sequences effectively and consider the influence of the scene change on the coding quality. This article combines hierarchical B frames forecasting pyra-mid coding structure of H. 264/SVC, presents an improved real-time algorithm of scene change detection based on image com-plexity, and modify quantization parameters of different temporal B frames when GOP encoding unit exists scene change. Experi-mental results show that does not produce mutation of channel bit rate and significantly improves video quality at the scene change.