A low power lossy frame memory recompression algorithm.

With the development of Ultra-High-Definition video, the power consumed by accessing reference frames in the external DRAM has become the bottleneck for the portable video encoding system design. To reduce the dynamic power of DRAM, a lossy frame memory recompression algorithm is proposed. The compression algorithm is composed of a content-aware adaptive quantization, a multi-mode directional prediction, a dynamic kth-order unary/Exp-Golomb coding and a partition group table based storage space reduction scheme. Experimental results show that, an average data reduction ratio of 71.1% is obtained, while 41% memory space can be saved. 59.6% dynamic power of the DRAM is reduced by our strategies in total. The algorithm causes a controllable video quality degradation, and the BD-PSNR is only -0.04db, or equivalently BD-BR=1.42%.