应用于HDTV的一种有效码率控制算法

An Efficient Rate Control Algorithm for HDTV

给出了一种结合码字预分配和直接缓冲器控制的码率控制方法．这种方法主要根据不同图象的性质对各图象按目标码字进行预分配，并使压缩时码字尽量与此相符，但在缓冲器接近溢出时则相应加强缓冲器控制．为使图象质量在帧内和帧间保持平稳，这里将压缩产生的码字与分配码字的差，分为性质不同的帧内余量和帧间余量分别处理并控制量化级的变化．

In this paper a rate control method is studied that combines pre-distribution of bits with direct buffer control. The method pre-distributes target code bits for every picture according to the characteristics of the picture, and makes the generated code bits as close as the target code bits. When buffer is going to overflow or underflow, the buffer control takes effect. To stabilize the quality of the image in one picture or among several pictures, the difference between generated and pre-distributed code bits is divided into two kinds: intra-picture difference and inter-picture difference. The two kinds of difference are of different characteristics and should be processed differently to control the quantization level.