摘要 |
A system for rate control and buffer management during coding of multiple variable bit rate digital video programs over a constant bit rate channel. The system is suitable for use in a hierarchical bit allocation scheme that includes a super group of pictures (GOP) level, a super frame level, and a frame level. For each super GOP with a length N frames, for each video program, the transmission rate for the current frame is set according to an average number of compressed bits for at least N previous frames, including a frame starting at N'+N-1 frames before the current frame, a frame ending at N' frames before the current frame, and intermediate frames therebetween. N' is a decoding delay of a modeled decoder that receives a respective video program. Moreover, the transmission rates of future frames are pre-set so that the average input rate of each individual video stream to the respective decoder buffer is equal to the average output rate, and the total transmission rate of programs is equal to the channel rate. |