Parametric audio coding based on adaptive signal models

This paper deals with the application of adaptive signal models for parametric audio coding. The matching pursuit algorithm is used for extracting sinusoidal components and transients in audio signals. The resulting residue is perceptually modelled as a noise like signal. First of all, an accurate detection of transients in audio signals is required. When a transient is detected, psychoacoustic-adapted matching pursuits are accomplished using a wavelet-based dictionary followed of an harmonic one. Otherwise, matching pursuit is applied only to the harmonic dictionary. This multi-part model (Sines + Transients + Noise) is successfully applied for audio coding purposes, assuring high perceptual audio quality at low bit rates (lower than 24 kbps for most of the CD-quality one channel audio signals considered for testing).