En poursuivant votre navigation sur ce site, vous acceptez l'utilisation d'un simple cookie d'identification. Aucune autre exploitation n'est faite de ce cookie. OK

30 Years of Wavelets 18 résultats

Filtrer
Sélectionner : Tous / Aucun
P Q
Déposez votre fichier ici pour le déplacer vers cet enregistrement.
y

Continuous and discrete uncertainty principles - Torrésani, Bruno (Auteur de la Conférence) | CIRM H

Multi angle

Uncertainty principles go back to the early years of quantum mechanics. Originally introduced to describe the impossibility for a function to be sharply localized in both the direct and Fourier spaces, localization being measured by variance, it has been generalized to many other situations, including different representation spaces and different localization measures.
In this talk we first review classical results on variance uncertainty inequalities (in particular Heisenberg, Robertson and Breitenberger inequalities). We then focus on discrete (and in particular finite-dimensional) situations, where variance has to be replaced with more suitable localization measures. We then present recent results on support and entropic inequalities, describing joint localization properties of vector expansions with respect to two frames.

Keywords: uncertainty principle - variance of a function - Heisenberg inequality - support inequalities - entropic inequalities[-]
Uncertainty principles go back to the early years of quantum mechanics. Originally introduced to describe the impossibility for a function to be sharply localized in both the direct and Fourier spaces, localization being measured by variance, it has been generalized to many other situations, including different representation spaces and different localization measures.
In this talk we first review classical results on variance uncertainty ...[+]

94A12 ; 94A17 ; 26D20 ; 42C40

Sélection Signaler une erreur
Déposez votre fichier ici pour le déplacer vers cet enregistrement.
y

Sound, music and wavelets in Marseille - Kronland-Martinet, Richard (Auteur de la Conférence) | CIRM H

Multi angle

In this conference, I start by presenting the first applications and developments of wavelet methods made in Marseille in 1985 in the framework of sounds and music. A description of the earliest wavelet transform implementation using the SYTER processor is given followed by a discussion related to the first signal analysis investigations. Sound examples of the initial sound transformations obtained by altering the wavelet representation are further presented. Then methods aiming at estimating sound synthesis parameters such as amplitude and frequency modulation laws are described. Finally, new challenges brought by these early works are presented, focusing on the relationship between low-level synthesis parameters and sound perception and cognition. An example of the use of the wavelet transforms to estimate sound invariants related to the evocation of the "object" and the "action" is presented.

Keywords : sound and music - first wavelet applications - signal analysis - sound synthesis - fast wavelet algorithms - instantaneous frequency estimation - sound invariants[-]
In this conference, I start by presenting the first applications and developments of wavelet methods made in Marseille in 1985 in the framework of sounds and music. A description of the earliest wavelet transform implementation using the SYTER processor is given followed by a discussion related to the first signal analysis investigations. Sound examples of the initial sound transformations obtained by altering the wavelet representation are ...[+]

00A65 ; 42C40 ; 65T60 ; 94A12 ; 97M10 ; 97M80

Sélection Signaler une erreur
Déposez votre fichier ici pour le déplacer vers cet enregistrement.
y

Noncommutative geometry and time-frequency analysis - Luef, Franz (Auteur de la Conférence) | CIRM H

Multi angle

In my talk I am presenting a link between time-frequency analysis and noncommutative geometry. In particular, a connection between the Moyal plane, noncommutative tori and time-frequency analysis. After a brief description of a dictionary between these two areas I am going to explain some consequences for time-frequency analysis and noncommutative geometry such as the construction of projections in the mentioned operator algebras and Gabor frames.

Keywords: modulation spaces - Banach-Gelfand triples - noncommutative tori - Moyal plane - noncommutative geometry - deformation quantization[-]
In my talk I am presenting a link between time-frequency analysis and noncommutative geometry. In particular, a connection between the Moyal plane, noncommutative tori and time-frequency analysis. After a brief description of a dictionary between these two areas I am going to explain some consequences for time-frequency analysis and noncommutative geometry such as the construction of projections in the mentioned operator algebras and Gabor ...[+]

46Fxx ; 46Kxx ; 46S60 ; 81S05 ; 81S10 ; 81S30

Sélection Signaler une erreur
Déposez votre fichier ici pour le déplacer vers cet enregistrement.
y

Phase-space delocalization - Paul, Thierry (Auteur de la Conférence) | CIRM H

Multi angle

Sélection Signaler une erreur
Déposez votre fichier ici pour le déplacer vers cet enregistrement.
y

An « ISI » perspective on wavelets - Flandrin, Patrick (Auteur de la Conférence) | CIRM H

Multi angle

The introduction of wavelets in the mid 80's has significantly reshaped some areas of the scientific landscape by establishing bridges between previously disconnected domains, and eventually leading to a new paradigm. This generally accepted-yet loose-claim can be given a more precise form by exploiting bibliometric databases such as the ISI Web of Science. Preliminary results in this direction will be reported here, based on multiple entries where authors, references, keywords and disciplines are used as nodes of a network in which the links correspond to their co-appearance in the same paper. While the evolution in time of such an « heterogeneous net » gives a quantified perspective on the birth and growth of wavelets as a well-identified scientific field of its own, it also raises many interpretation issues (related, e.g., to automation vs. expertise) whose implications go beyond this peculiar case study.

Keywords : wavelets - history - bibliometry - network, paradigm[-]
The introduction of wavelets in the mid 80's has significantly reshaped some areas of the scientific landscape by establishing bridges between previously disconnected domains, and eventually leading to a new paradigm. This generally accepted-yet loose-claim can be given a more precise form by exploiting bibliometric databases such as the ISI Web of Science. Preliminary results in this direction will be reported here, based on multiple entries ...[+]

01-XX ; 42-XX ; 68-XX ; 94-XX

Sélection Signaler une erreur
Déposez votre fichier ici pour le déplacer vers cet enregistrement.
y

Continuous (semi-)frames revisited - Antoine, Jean-Pierre (Auteur de la Conférence) | CIRM H

Multi angle

We start by recalling the essential features of frames, both discrete and continuous, with some emphasis on the notion of frame duality. Then we turn to generalizations, namely upper and lower semi-frames, and their duality. Next we consider arbitrary measurable maps and examine the standard operators, analysis, synthesis and frame operators, and study their properties. Finally we analyze the recent notion of reproducing pairs. In view of their duality structure, we introduce two natural partial inner product spaces and formulate a number of open questions.

Keywords: continuous frames - semi-frames - frame duality - reproducing pairs - partial inner product spaces[-]
We start by recalling the essential features of frames, both discrete and continuous, with some emphasis on the notion of frame duality. Then we turn to generalizations, namely upper and lower semi-frames, and their duality. Next we consider arbitrary measurable maps and examine the standard operators, analysis, synthesis and frame operators, and study their properties. Finally we analyze the recent notion of reproducing pairs. In view of their ...[+]

42C15 ; 42C40 ; 46C50 ; 65T60

Sélection Signaler une erreur
Déposez votre fichier ici pour le déplacer vers cet enregistrement.
y

The joy and pain of wavelets in numerical simulation - Cohen, Albert (Auteur de la Conférence) | CIRM H

Multi angle

Sélection Signaler une erreur
Déposez votre fichier ici pour le déplacer vers cet enregistrement.
y
This presentation reminds of some early sonic representations and of their utility for musical sound synthesis and processing, prior to the introduction of wavelets by Morlet and Grossmann. It reminds the circumstances of the work performed at the Laboratoire de Mécanique et d'Acoustique, Marseille, by Richard Kronland-Martinet with Alex Grossmann on wavelet transforms of sounds and by Daniel Arfib and Frédéric Boyer on the Gabor representation. It is illustrated by short sound and video examples.[-]
This presentation reminds of some early sonic representations and of their utility for musical sound synthesis and processing, prior to the introduction of wavelets by Morlet and Grossmann. It reminds the circumstances of the work performed at the Laboratoire de Mécanique et d'Acoustique, Marseille, by Richard Kronland-Martinet with Alex Grossmann on wavelet transforms of sounds and by Daniel Arfib and Frédéric Boyer on the Gabor representation. ...[+]

42-03

Sélection Signaler une erreur
Déposez votre fichier ici pour le déplacer vers cet enregistrement.
y

Sélection Signaler une erreur
Déposez votre fichier ici pour le déplacer vers cet enregistrement.
Sélection Signaler une erreur