Xue Wen

Contact Details

Title: Research assistant on OMRAS2
Tel: National: 020 7882 5528
International: +44 20 7882 5528
Fax: National: 020 7882 7997
International: +44 20 7882 7997
Email: xue.wen@elec.qmul.ac.uk
Room: 112

Research Group: Centre for Digital Music

Research Topic: Harmonic sinusoid modeling and applications

Harmonic sinusoid model is a parametric model that expresses an audio signal, or part of an audio signal, as the linear combination of concurrent slow-varying sinusoids, grouped together under harmonic frequency constraints. The harmonic sinusoid modeling is an extension of the sinusoid modeling, with the additional frequency constraints so that it is capable to directly model tonal sounds. This enables applications such as object-oriented audio manipulations, polyphonic transcription, instrument/singer recognition with background music, etc.

The modeling system consists of an analyzer and a synthesizer. The analyzer extracts harmonic sinusoidal parameters from an audio waveform, while the synthesizer rebuilds an audio waveform from these parameters.

Parameter estimation is based on a detecting-grouping-tracking framework.
The detecting stage finds and estimates sinusoid atoms; the grouping stage collects concurrent atoms into harmonic groups; the tracking stage collects the atom groups at different time to form continuous harmonic sinusoid tracks. Compared to standard sinusoid model, the harmonic model focuses on harmonic groups of atoms rather than on isolated atoms, therefore naturally represents pitched tonal sounds. The synthesizer rebuilds the audio signal by interpolating measured parameters along the found tracks.

We propose the first application of the harmonic sinusoid model in digital audio editors. For audio editing, with the tonal events directly represented by a parametric model, we can implement standard audio editing functionalities on tonal events embedded in an audio signal, or invent new sound effects based on the model parameters themselves. Other suggested applications include music transcription and instrument recognition, annotation, onset detection, coding, and music performance analysis.

Publications

Wen X. and M. Sandler, "Calculation of radix-2 discrete multiresolution Fourier transform," Signal Processing, vol. 87 no.10, 2007, pp.2455-2460.

Wen X. and M. Sandler, "New audio editor functionality using harmonic sinusoids," in Proc. AES122nd Convention, Vienna, 2007.

Wen X. and M. Sandler, "Sinusoid modeling in a harmonic context," in Proc.
DAFx'07, Bordeaux, 2007.

Wen X. and M. Sandler, "Error compensation in modeling time-varying sinusoids," in Proc. DAFx’06, Montreal, 2006.

Wen X. and M. Sandler, "Transcribing piano music using signal novelty," in Proc. AES 118th Convention, Barcelona, 2005.

Wen X. and M. Sandler, "A partial searching algorithm and its application for polyphonic transcription," in Proc. ISMIR’05, London, 2005.