A simple and low-cost MPEG audio degrouping algorithm

Degrouping is the key component in MPEG Layer II audio decoding. It mainly contains the arithmetic operations of division and modulo, which require lots of hardware and computation time. In this paper, we propose a novel degrouping algorithm with a low complexity design concept. By using mode selection and iterative decomposition, only the addition and subtraction are needed. The elimination of the multiplier, divider and ROM table can therefore save a lot of chip area, but still keeps the high efficiency without loss of any accuracy.