EURASIP Journal on Applied Signal Processing 
Volume 2005 (2005), Issue 9, Pages 1292-1304
doi:10.1155/ASP.2005.1292

A Perceptual Model for Sinusoidal Audio Coding Based on Spectral Integration

Steven van de Par,1 Armin Kohlrausch,1,2 Richard Heusdens,3 Jesper Jensen,3 and Søren Holdt Jensen4

 1Digital Signal Processing Group, Philips Research Laboratories, Eindhoven 5656 AA, The Netherlands
2Department of Technology Management, Eindhoven University of Technology, Eindhoven 5600 MB, The Netherlands
3Department of Mediamatics, Delft University of Technology, Delft 2600 GA, The Netherlands
4Department of Communication Technology, Institute of Electronic Systems, Aalborg University, Aalborg DK-9220, Denmark
Received 31 October 2003; Revised 22 July 2004

Abstract

Psychoacoustical models have been used extensively within audio coding applications over the past decades. Recently, parametric coding techniques have been applied to general audio and this has created the need for a psychoacoustical model that is specifically suited for sinusoidal modelling of audio signals. In this paper, we present a new perceptual model that predicts masked thresholds for sinusoidal distortions. The model relies on signal detection theory and incorporates more recent insights about spectral and temporal integration in auditory masking. As a consequence, the model is able to predict the distortion detectability. In fact, the distortion detectability defines a (perceptually relevant) norm on the underlying signal space which is beneficial for optimisation algorithms such as rate-distortion optimisation or linear predictive coding. We evaluate the merits of the model by combining it with a sinusoidal extraction method and compare the results with those obtained with the ISO MPEG-1 Layer I-II recommended model. Listening tests show a clear preference for the new model. More specifically, the model presented here leads to a reduction of more than 20% in terms of number of sinusoids needed to represent signals at a given quality level.