A rate control algorithm using macroblock types

ISO/IEC MPEG-3 Test Model 5 (TM5) describes a rate control scheme which consists of three steps: bit allocation, rate control and modulation. However, there are basically two problems with the TM5 rate control. First, macroblocks in a picture may not all be treated equally. Secondly, the TM5 rate control does not handle scene changes properly. Although several schemes have been developed to solve these problems of TM5, none of them exploits the information of the macroblocks to be coded. We propose a new rate control strategy by using coded types of macroblocks within a picture. With the proposed algorithm, we can get a more consistent picture quality, and avoid buffer overflow and underflow.