Optimal frame memory and data transfer scheme for MPEG-4 shape coding

An optimal frame memory and data transfer scheme is proposed for MPEG-4 shape coding in embedded systems. Based on the inherent property of shape information, the binary alpha blocks are losslessly compressed with a fixed 50% compression ratio and can be randomly accessed. Therefore the size of frame memory can be reduced to 50% with a small index table (2.73% to 5.08% of the original frame memory size), and the number of memory references can be reduced to 56.25%. The data transfer scheme combines the run length coding and addressing mode to reduce data transfer time to 9.39%.