Un algorithme rapide d'extraction d'arêtes dans le scalogramme et son utilisation dans la recherche de zones stationnaires

Un algorithme rapide d'extraction d'arêtes dans le scalogramme et son utilisation dans la recherche de zones stationnaires

A fast ridge extraction algorithm from the scalogram, applied to search of stationary areas

Hélène Leman Catherine Marque 

Université de Technologie de Compiègne, UMR CNRS 6600, Compiègne

Corresponding Author Email: 
8 March 1998
31 December 1998
| Citation



We propose to extract the ridges from the scalogram, with the help of a rapid and simple algorithm, based on the local maxima detection, their linkage and their interpolation. The signal reconstruction is possible thanks to the Marseille's algorithm, proposed in 1990. Moreover, the reconstruction, from a limited number of ridges of greatest energy, makes the stationarity research easier. Indeed, the reconstructed version of the signal is, in someway, a simplified version of the original signal . We apply these methods to the uterine electromyogram signal, in order to characterize the contractions during pregnancy.


Nous proposons d'extraire les arêtes dans le scalogramme, grâce à un algorithme rapide et simple, basé sur la détection des maxima locaux, leur lien et leur interpolation . La reconstruction du signal est possible grâce à l'algorithme proposé par Marseille en 1990 . La recherche de zones stationnaires est alors facilitée par la reconstruction du signal, à partir d'un certain nombre d'arêtes . En effet, la version reconstruite est, en quelque sorte, une version «simplifiée» du signal original. Nous appliquons ces méthodes au signal électromyographique utérin, en vue d'une caractérisation des contractions utérines pendant la grossesse.


Electrohysterogram, ridges, scalogram, stationnarity

Mots clés

Électrohystérogramme, arêtes, scalogramme, stationnarité

1. Introduction
2. Principe De L'algorithme
3. Détection De Zones De Stationnarité
4. Résultats : Application À L'EMG Utérin
5. Conclusion

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