Rate control of MPEG video coding and recording by rate-quantization modeling

For MPEG video coding and recording applications, it is important to select the quantization parameters at slice and macroblock levels to produce consistent quality image for a given bit budget. A well-designed rate control strategy can improve the overall image quality for video transmission over a constant-bit-rate channel and fulfil the editing requirement of video recording, where a certain number of new pictures are encoded to replace consecutive frames on the storage media using, at most, the same number of bits. We developed a feedback re-encoding method with a rate-quantization model, which can be adapted to changes in picture activities. The model is used for quantization parameter selection at the frame and slice level. The extra computations needed are modest. Experiments show the accuracy of the model and the effectiveness of the proposed rate control method. A new bit allocation algorithm is then proposed for MPEG video coding