Localisation fréquentielle des paquets d'ondelettes.
Eric Séré (1995)
Revista Matemática Iberoamericana
Similarity:
Orthonormal bases of wavelet packets constitute a powerful tool in signal compression. It has been proved by Koifman, Meyer and Wickerhauser that many wavelet packets w suffer a lack of frequency localization. Using the L-norm of the Fourier transform ^w as localization criterion, they showed that the average 2Σ ||^w|| blows up as j goes to infinity. A natural problem is then to know which values of n create this blow-up in average. The present work gives an answer to...