An effective real-time rate control scheme for video codec

To reduce the complexity of the bit allocation scheme for real-time video codec and keep an acceptable video quality, an effective rate control scheme combined with the fast mode decision is proposed. The length of each GOP(group of pictures) is dynamically determined according to the content of the video clip. The algorithm employs a MAD-tracing based model to allocate bit budget between frames within the same GOP. More motional and active macroblocks(MBs) get more bits than other MBs in the same frame. The median result then can be reused to accelerate fast mode decision procedure. Experimental results show the proposed methods can enhance the overall quality of compressed video.