EURASIP Journal on Applied Signal Processing 
Volume 2005 (2005), Issue 9, Pages 1350-1364
doi:10.1155/ASP.2005.1350

Neuromimetic Sound Representation for Percept Detection and Manipulation

Dmitry N. Zotkin,1 Taishih Chi,2 Shihab A. Shamma,2 and Ramani Duraiswami1

 1Perceptual Interfaces and Reality Laboratory, Institute for Advanced Computer Studies (UMIACS), University of Maryland, College Park 20742, MD, USA
2Neural Systems Laboratory, The Institute for Systems Research, University of Maryland, College Park 20742, MD, USA
Received 2 November 2003; Revised 4 August 2004

Abstract

The acoustic wave received at the ears is processed by the human auditory system to separate different sounds along the intensity, pitch, and timbre dimensions. Conventional Fourier-based signal processing, while endowed with fast algorithms, is unable to easily represent a signal along these attributes. In this paper, we discuss the creation of maximally separable sounds in auditory user interfaces and use a recently proposed cortical sound representation, which performs a biomimetic decomposition of an acoustic signal, to represent and manipulate sound for this purpose. We briefly overview algorithms for obtaining, manipulating, and inverting a cortical representation of a sound and describe algorithms for manipulating signal pitch and timbre separately. The algorithms are also used to create sound of an instrument between a “guitar” and a “trumpet.” Excellent sound quality can be achieved if processing time is not a concern, and intelligible signals can be reconstructed in reasonable processing time (about ten seconds of computational time for a one-second signal sampled at 8 kHz). Work on bringing the algorithms into the real-time processing domain is ongoing.