A lossless frame recompression scheme for reducing DRAM power in video encoding

Owing to the huge bandwidth requirement, the DRAM power composes a significant portion of the power consumed by video coding system. In this paper, a lossless frame recompression scheme for reducing DRAM bandwidth is presented. The basic structure of the scheme which includes the memory organization, the data fetching strategy as well as the cache organization is proposed. Furthermore, an adaptive DPCM (Differential Pulse Code Modulation) scanning order selection is used and an efficient coding method that is suitable for compressing the DPCM samples in reference frames is also discussed. Experimental results show a 50%~60% saving of bandwidth on 720p and 1080p sequences, which indicates that the proposed scheme can be useful in reducing the system power through saving DRAM bandwidth.