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Perceptually motivated time-frequency analysis.

Jonathan J O'Donovan·Dermot J Furlong
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Abstract

This paper describes the design of a bilinear time-frequency distribution which is a joint model of temporal and spectral masking. The distribution is used to generate temporally evolving excitation patterns of nonstationary signals and systems and is conceived as a tool for acousticians and engineers for perceptual time-frequency analysis. Distribution time and frequency resolutions are controlled by a separable kernel consisting of a set of low-pass time and frequency smoothing windows. These windows are designed by adapting existing psychoacoustic models of auditory resolution, rather than using mathematical window functions. Cross-term interference and windowing clutter are highly suppressed for the distribution, ensuring resolution accuracy over a dynamic range sufficient to encompass that of the auditory system (in excess of 100 dB). Application to the analysis of a synthetic and two real signals are included to demonstrate the approach.

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AlgorithmsAuditory PerceptionHumansModels, TheoreticalPerceptual MaskingPsychoacousticsSignal Processing, Computer-AssistedTime FactorsJournal ArticleResearch Support, Non-U.S. Gov't

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Jonathan J O'Donovan, Dermot J Furlong. 2005. Perceptually motivated time-frequency analysis.. https://doi.org/10.1121/1.1831283

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