Publications

Articles, Thèses, Brevets, Séminaires, Livres, Notes techniques

Recherche

Article de journal

Foldings of Periodic Nonuniform Samplings

Auteurs : Lacaze Bernard et Fabre Serge

IEEE Transactions on Circuits and Systems II, vol. 69, issue 3, pp. 1862-1868, March 2022.

Télécharger le document

Periodic Nonuniform Samplings of order N (PNSN) are interleavings of periodic samplings. For a base period T, simple algorithms can be used to reconstruct functions of spectrum included in an union of N intervals δk of length 1/T. In this paper we study the behavior of these algorithms when applied to any function. We prove that they result in N (or less) foldings on , each of δk holding at most one folding.

Lire la suite

Traitement du signal et des images / Autre

Article de conférence

Modèles de Markov cachés appliqués au masquage de perte de paquets en voix sur IP

Auteurs : Koenig Lionel, André-Obrecht Régine, Mailhes Corinne et Fabre Serge

In Proc. Groupement de Recherche en Traitement du Signal et des Images (GRETSI), September 8-11, 2009.

Télécharger le document

Packet loss due to misrouted or delayed packets in voice over IP leads to huge voice quality degradation. This paper presents a packet loss concealement algorithm which is inde pendant from the vocoder. This method relies on hidden Marko v model (HMM). A new voicing parameter is introduced to get ove r voiced/unvoiced sound separation and use a unique HMM. Since best parameter for prediction are not necessarily the best ones for synthesis, we introduce two separate vectors: the first one dedicated to the analysis of the signal and the second one featured for the synthesis of missing part. Performances of the proposed system are evaluated on parts of well-known speech corpora, leading to promising results.

Lire la suite

Traitement du signal et des images / Systèmes spatiaux de communication

A New Feature Vector for HMM-Based Packet Loss Concealment

Auteurs : Koenig Lionel, André-Obrecht Régine, Mailhes Corinne et Fabre Serge

In Proc. European Signal and Image Processing Conference (EUSIPCO), Glasgow, Scotland, August 24-28, 2009.

Télécharger le document

Packet loss due to misrouted or delayed packets in voice over IP leads to huge voice quality degradation. Packet loss con- cealment algorithms try to enhance the quality of the speech. This paper presents a new packet loss concealment algorithm which relies on one hidden Markov model. For this purpose, we introduce a continuous observation vector well-suited for silence, voiced and unvoiced sounds. We show that having a global HMM is relevant for this application. The proposed system is evaluated using standard PESQ score in a real- world application.

Lire la suite

Traitement du signal et des images / Autre

A Continuous Voicing Parameter in the Frequency Domain

Auteurs : Koenig Lionel, André-Obrecht Régine, Mailhes Corinne et Fabre Serge

In Proc. Int. Conf. on Speech and Computer (SPECOM), Saint Petersbourg, Russia, June 23-25, 2009.

Télécharger le document

In automatic speech analysis, voicing articulatory is often defined as a binary decision: voiced or unvoiced. Lin- guists agree that this articulatory should be continuous. In this paper, we present a new approach to compute a con- tinuous voicing indicator of a speech frame. This voic- ing percentage is then evaluated in both a segmentation process and a speech recognition task. Promising results show that this continuous voicing percentage may be used as a reliable voicing indicator.

Lire la suite

Traitement du signal et des images / Autre

ADRESSE

7 boulevard de la Gare
31500 Toulouse
France

CONTACT


CNES
Thales Alenia Space
Collins Aerospace
SpaceAble
Toulouse INP
ISEA-SUPAERO
IPSA
ENAC
IMT Atlantique