Catégorie de document |
Article ou chapitre dans un livre |
Titre |
An Entropy Based Method for Local Time-Adaptation of the Spectrogram |
Auteur principal |
Marco Liuni |
Co-auteurs |
Axel Roebel, Marco Romito, Xavier Rodet |
Paru dans |
Lecture Notes in Computer Science, Computer Music Modeling and Retrieval. Exploring Music Contents, Berlin, 2011, Springer Verlag |
Collation |
p.60-75 |
Copyright |
Springer-Verlag Berlin Heidelberg 2011 |
Année |
2011 |
Statut éditorial |
Publié |
Résumé |
We propose a method for automatic local time-adaptation of the spectrogram of audio signals: it is based on the decomposition of a signal within a Gabor multi-frame through the STFT operator. The sparsity of the analysis in every individual frame of the multi-frame is evaluated through the Rényi entropy measures: the best local resolution is determined minimizing the entropy values. The overall spectrogram of the signal we obtain thus provides local optimal resolution adaptively evolving over time. We give examples of the performance of our algorithm with an instrumental sound and a synthetic one, showing the improvement in spectrogram displaying obtained with an automatic adaptation of the resolution. The analysis operator is invertible, thus leading to a perfect reconstruction of the original signal through the analysis coefficients. |
Mots-clés |
adaptive spectrogram / sound representation / sound analysis / sound synthesis / Rényi entropy / sparsity measures / frame theory. |
Equipe |
Analyse et synthèse sonores |
Cote |
Liuni11a |
Adresse de la version en ligne |
http://articles.ircam.fr/textes/Liuni11a/index.pdf |
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