Abstract: To reduce the complexity of bit allocation scheme for real-time video coding and keep an acceptable video quality， an effective rate control scheme is proposed.The length of each GOP is dynamically determined according to the complexity of the video clip.The algorithm employs a simplified content-based model to allocate bit budget between frames within GOP.Those macroblocks containing more motional information get more bits than other ones in the same frame.Experimental results show the proposed methods can enhance the overall quality of compressed video.

Key words: Rate Control（RC）, dynamic GOP length, video encoding

摘要： 为提供实时视频传输服务，同时保证一定的视频质量，提出了一种基于JVT-G012的动态码率控制算法。在编码过程中，根据图像内容的运动特性，动态决定GOP长度，同时防止输出缓冲器的上溢和下溢；为复杂度较高的宏块（MB）分配较多的比特。实验结果表明，该算法对于场景变化较大的实际视频序列有较好的编码效果。

关键词: 码率控制, 动态图像组, 视频编码