Low power MPEG/audio encoders using simplified psychoacoustic model and fast bit allocation

Abstract

We propose novel techniques for the implementation of MPEG/audio (Layer II and Layer III) encoder. The proposed techniques concern implementing the encoder with a minimum complexity. As an effort to minimize the complexity, the ISO psychoacoustic model (PAM) is simplified that often demands significant computational power of the implementation system. The simplification follows the statistical behavior of the PAM. A fast bit allocation algorithm is also developed, in which the quantizer step size is updated dynamically and adaptively according to the input signal statistics. The performance of the developed techniques is verified via subjective tests as well as statistical analyses. Real-time implementations are tried for MPEG/audio Layer II and Layer III encoders employing the proposed algorithms. The implemented systems show that the developed encoders can be as simple as decoders, but still produce bitstreams of high audio quality.