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On modeling the STFT phase of audio signals with the von Mises distribution

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review


Original languageEnglish
Title of host publication16th International Workshop on Acoustic Signal Enhancement, IWAENC 2018
ISBN (Electronic)9781538681510
Publication statusPublished - 2 Nov 2018
Publication typeA4 Article in a conference publication
EventInternational Workshop on Acoustic Signal Enhancement - Tokyo, Japan
Duration: 17 Sep 201820 Sep 2018


ConferenceInternational Workshop on Acoustic Signal Enhancement


In this paper, we study statistical models for the phase of the short-term Fourier transform (STFT) of audio signals. STFT phase globally appears as uniformly distributed, which has led researchers in this field to model it as a uniform random variable. However, some information about the phase can be obtained from a sinusoidal model, which reveals its local structure. Therefore, we propose to model the phase with a von Mises (VM) random variable, which enables us to favor the sinusoidal model-based phase value. We estimate the distribution parameters and we validate this model on real audio data. In particular, we observe that both models (uniform and VM) are relevant from a statistical perspective but they convey different information about the phase (global vs. local). We also apply this VM model to an audio source separation task, where it outperforms previous approaches.

Publication forum classification

Field of science, Statistics Finland