A matched FIR filter bank for audio coding

Abstract

This paper describes a novel technique for audio coding, a lossy compression algorithm, that considers perceptual and rate-distortion criteria. It is based on matched finite impulse response (FIR) wavelet-packet-like filter banks, the filter coefficients being produced adoptively according to the input signal. This technique achieves perceptually transparent coding of high-quality audio, signals sampled at 44.1 KHz - 16 bits PCM, at bit rates of about 54 - 64 Kbps. The matched filter-bank makes a time-frequency-shape analysis, reducing the number of sub-bands requiring quantization. The decoder that implements this algorithm works effectively in real time. This reassures the efficacy of our technique.