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Lucas Ondel

11 accepted papers

2022

GPU-Accelerated Forward-Backward Algorithm with Application to Lattice-Free MMI

ICASSP 2022accepted

We propose to express the forward-backward algorithm in terms of operations between sparse matrices in a specific semiring. This new perspective naturally leads to a GPU-friendly algorithm which is easy to implement in Julia or any programming languages with native support of semiring algebra. We us…

Cited by 0SourceScholar
2021

A Hierarchical Subspace Model for Language-Attuned Acoustic Unit Discovery

ICASSP 2021accepted

In this work, we propose a hierarchical subspace model for acoustic unit discovery. In this approach, we frame the task as one of learning embeddings on a low-dimensional phonetic subspace, and simultaneously specify the subspace itself as an embedding on a hyper-subspace. We train the hyper-subspac…

Cited by 12SourceScholar
2019

Deriving Spectro-temporal Properties of Hearing from Speech Data

ICASSP 2019accepted

Human hearing and human speech are intrinsically tied together, as the properties of speech almost certainly developed in order to be heard by human ears. As a result of this connection, it has been shown that certain properties of human hearing are mimicked within data-driven systems that are train…

Cited by 0SourceScholar
2019

Towards Automatic Methods to Detect Errors in Transcriptions of Speech Recordings

ICASSP 2019accepted

This work explores different methods to detect errors in transcriptions of speech recordings. We artificially corrupt well transcribed speech transcriptions with three types of errors: substitution, insertion and deletion on TIMIT phonemic transcriptions and WSJ word transcriptions. First, we use Ba…

Cited by 0SourceScholar
2018

Bayesian Models for Unit Discovery on a Very Low Resource Language

ICASSP 2018accepted

Developing speech technologies for low-resource languages has become a very active research field over the last decade. Among others, Bayesian models have shown some promising results on artificial examples but still lack of in situ experiments. Our work applies state-of-the-art Bayesian models to u…

Cited by 0SourceScholar
2018

Linguistic Unit Discovery from Multi-Modal Inputs in Unwritten Languages: Summary of the "Speaking Rosetta" JSALT 2017 Workshop

ICASSP 2018accepted

We summarize the accomplishments of a multi-disciplinary workshop exploring the computational and scientific issues surrounding the discovery of linguistic units (subwords and words) in a language without orthography. We study the replacement of orthographic transcriptions by images and/or translate…

Cited by 0SourceScholar
2017

An empirical evaluation of zero resource acoustic unit discovery

ICASSP 2017accepted

Acoustic unit discovery (AUD) is a process of automatically identifying a categorical acoustic unit inventory from speech and producing corresponding acoustic unit tokenizations. AUD provides an important avenue for unsupervised acoustic model training in a zero resource setting where expert-provide…

Cited by 0SourceScholar
2017

Bayesian joint-sequence models for grapheme-to-phoneme conversion

ICASSP 2017accepted

We describe a fully Bayesian approach to grapheme-to-phoneme conversion based on the joint-sequence model (JSM). Usually, standard smoothed n-gram language models (LM, e.g. Kneser-Ney) are used with JSMs to model graphone sequences (joint grapheme-phoneme pairs). However, we take a Bayesian approach…

Cited by 0SourceScholar
2017

Bayesian phonotactic Language Model for Acoustic Unit Discovery

ICASSP 2017accepted

Recent work on Acoustic Unit Discovery (AUD) has led to the development of a non-parametric Bayesian phone-loop model where the prior over the probability of the phone-like units is assumed to be sampled from a Dirichlet Process (DP). In this work, we propose to improve this model by incorporating a…

Cited by 0SourceScholar
2017

Topic identification of spoken documents using unsupervised acoustic unit discovery

ICASSP 2017accepted

This paper investigates the application of unsupervised acoustic unit discovery for topic identification (topic ID) of spoken audio documents. The acoustic unit discovery method is based on a non-parametric Bayesian phone-loop model that segments a speech utterance into phone-like categories. The di…

Cited by 0SourceScholar