This afternoon one of our PhD student researchers, Will Wilkinson, successfully defended his PhD. The form of these exams, or vivas, varies from country to country, and even institution to institution, which we discussed previously. Here, its pretty gruelling; behind closed doors, with two expert examiners probing every aspect of the PhD.
Will’s PhD was on ‘Gaussian Process Modelling for Audio Signals.’
Audio signals are characterised and perceived based on how their spectral make-up changes with time. Latent force modelling assumes these characteristics come about as a result of a common input function passing through some input-output process. Uncovering the behaviour of these hidden spectral components is at the heart of many applications involving sound, but is an extremely difficult task given the infinite number of ways any signal can be decomposed.
Will’s thesis studies the application of Gaussian processes to audio, which offer a way to specify probabilities for these functions whilst encoding prior knowledge about sound, the way it behaves, and the way it is perceived. Will advanced the theory considerably, and tested his approach for applications in sound synthesis, denoising and source separation tasks, among others.
http://c4dm.eecs.qmul.ac.uk/audioengineering/latent-force-synthesis/ – demonstrates some of his research applied to sound synthesis, and https://fxive.com/app/main-panel/Mammals.html is a real-time demonstration of his Masters work on sound synthesis for mammalian vocalisations.
- W. J. Wilkinson, M. R. Andersen, J. D. Reiss, D. Stowell, A. Solin, ‘Unifying probabilistic models for time-frequency analysis,’ IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 20196.
- W. J. Wilkinson, J. D. Reiss, D. Stowell, ‘A Generative Model for Natural Sounds Based on Latent Force Modelling,’ Arxiv pre-print version. International Conference on Latent Variable Analysis and Signal Separation, Guildford, UK, July 2018.
- W. J. Wilkinson, J. D. Reiss and D. Stowell, ‘Latent Force Models for Sound: Learning Modal Synthesis Parameters and Excitation Functions from Audio Recordings,’ 20th International Conference on Digital Audio Effects (DAFx-17), Edinburgh, UK, September 5–9, 2017
- W. Wilkinson, J. D. Reiss, A Synthesis Model for Mammalian Vocalization Sound Effects, 61st International AES Conference: Audio for Games, London 2016
- W. Wilkinson, D. Stowell and J. D. Reiss, “Performable spectral synthesis via low-dimensional modelling and control mapping“, DMRN+11: Digital Music Research Network Workshop, Dec. 2016
- W. J. Wilkinson, Michael Riis Andersen, Joshua D. Reiss, Dan Stowell, and Arno Solin, “End-to-End Probabilistic Inference for Non-stationary Audio Analysis” Int. Conference on Machine Learning (ICML), 2019