视频编码器的率控制

Rate Control Algorithms for Video Encoder

视频编码器工作于ＣＢＲ模式时，通常需要在编解码器和信道之间放置一个缓冲器（Ｂｕｆｅｒ），并由相应的码率控制单元调整量化参数以避免缓冲器产生溢出。同时，率控制策略对于解码后图象质量的一致性有较严重的影响。并论述了２种为防止Ｂｕｆｅｒ溢出的控制策略及其硬件实现。

Digital video has been transmitted using channels that have constant channel rate, so there always need a output buffer between the video encoder and the channel multiplexer when the encoder operates on the CBR mode. Rate control unit is responsible for avoiding overflowing or underflowing of the output buffer of the encoder. Here two rate control algorithms and their hardware implements are presented.