Memory compression method considering memory bandwidth for HDTV decoder LSIs

摘要

This paper proposes a frame memory compression method for an MPEG-2 Main Profile@High-Level (MP@HL) decoder LSI using Direct Rambus/sup TM/ DRAM (DRDRAM). The compression method is based on two-dimensional adaptive DPCM (2-D ADPCM) and is designed to achieve efficient memory access. HDTV bitstreams are decoded with a single 64 megabit (Mb) DRDRAM without subjective image quality degradation. Computer simulation is performed for ten HDTV bitstreams encoded at 22 Mbps. Simulation results show that, in the worst case, SNR loss compared to the full spec decoder is 0.71 dB for a luminance, 0.27 dB and 0.57 dB for chrominances.