Anthropomorphic Coding of Speech and Audio: A Model Inversion Approach
1 Signal Processing and Speech Communication Laboratory, Graz University of Technology, Graz 8010, Austria
2 Department for Signals, Sensors and Systems, KTH (Royal Institute of Technology), Stockholm 10044, Sweden
EURASIP Journal on Advances in Signal Processing 2005, 2005:571618 doi:10.1155/ASP.2005.1334Published: 21 June 2005
Auditory modeling is a well-established methodology that provides insight into human perception and that facilitates the extraction of signal features that are most relevant to the listener. The aim of this paper is to provide a tutorial on perceptual speech and audio coding using an invertible auditory model. In this approach, the audio signal is converted into an auditory representation using an invertible auditory model. The auditory representation is quantized and coded. Upon decoding, it is then transformed back into the acoustic domain. This transformation converts a complex distortion criterion into a simple one, thus facilitating quantization with low complexity. We briefly review past work on auditory models and describe in more detail the components of our invertible model and its inversion procedure, that is, the method to reconstruct the signal from the output of the auditory model. We summarize attempts to use the auditory representation for low-bit-rate coding. Our approach also allows the exploitation of the inherent redundancy of the human auditory system for the purpose of multiple description (joint source-channel) coding.