Publications de Martin Vetterli

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First published in 1995, Wavelets and Subband Coding offered a unified view of the exciting field of wavelets and their discrete-time cousins, filter banks, or subband coding. The book developed the theory in both continuous and discrete time, and presented important applications. During the past decade, it filled a useful need in explaining a new view of signal processing based on flexible time-frequency analysis and its applications. Since 2007, the authors now retain the copyright and allow open access t

We study the accuracy of triangulation in multi-camera systems with respect to the number of cameras. We show that, under certain conditions, the optimal achievable reconstruction error decays quadratically as more cameras are added to the system. Furtherm ...

Color image demosaicking is a key process in the digital imaging pipeline. In this paper, we present a rigorous treatment of a classical demosaicking algorithm based on alternating projections (AP). Since its publication, the AP algorithm has been widely cited and served as a benchmark in a flurry of papers in the demosaicking literature. Despite its impressive performances, a relative weakness of the AP algorithm is its high computational complexity. In our work, we provide a rigorous analysis of the conve

A new iterative low complexity algorithm has been presented for computing the Walsh-Hadamard transform (WHT) of an N dimensional signal with a K-sparse WHT, where N is a power of two and K = O(N^α), scales sub- linearly in N for some 0 < α < 1. Assuming a ...

We study the problem of multiple description (MD) coding of stationary Gaussian sources with memory. First, we compute an approximate rate distortion region for these sources, which we prove to be asymptotically tight at high rates: this region generalizes the standard MD rate distortion region for memoryless sources. Then we develop an algorithm for the design of optimal biorthogonal filter banks for MD coding. Finally. We present some experimental results, where we measure the deviation from optimality of

We consider the rate-distortion problem for recording a Gaussian acoustic field with an array of sensors equipped with microphones. Our analysis is based on the field's spatiotemporal correlation structure, which is induced by the physics of sound propagation. Under certain assumptions about the spectrum of the wave kernel, we determine the rate-distortion functions for various distributed source coding schemes and sampling lattices. Our results also include an answer to the multiterminal rate-distortion pr

Certain aspects of the present disclosure provide methods for distributed sensing and centralized reconstruction of two correlated signals, modeled as the input and output of an unknown sparse filtering operation. ...

In a variety of fields, in particular those involving imaging and optics, we often measure signals whose phase is missing or has been irremediably distorted. Phase retrieval attempts to recover the phase information of a signal from the magnitude of its Fo ...

We consider the position calibration problem in circular tomography devices, where sensors deviate from a perfect circle. We introduce a new method of calibration based on the time-of-flight measurements between sensors when the enclosed medium is homogene ...

The reconstruction of a diffusion field, such as temperature, from samples collected by a sensor network is a classical inverse problem and it is known to be ill-conditioned. Previous work considered source models, such as sparse sources, to regularize the ...

How can we decipher the hidden structure of a network based on limited observations? This question arises in many scenarios ranging from social to wireless and to neural networks. In such settings, we typically observe the nodes’ behaviors (e.g., the time ...

Consider a scenario where a distributed signal is sparse and is acquired by various sensors that see different versions. Thus, we have a set of sparse signals with both some common parts, and some variations. The question is how to acquire such signals and ...

The Karhunen-Loeve transform is a key element of many signal processing tasks, including classification and compression. In this paper, we consider distributed signal processing scenarios with limited communication between correlated sources, and we investigate a distributed Karhunen-Loeve transform (KLT). In particular, a partial KLT (where only a subset of sources are observed) and a conditional KLT (where some sources act as side information) are posed and solved in a rate-distortion sense. The partial K

Hearing aids are audio capture devices which aim at providing the hearing impaired with better audibility. Most of the state-of-the-art systems involve sensing devices that work independently. However, the availability of a wireless communication link betw ...

We study the problem of localizing a configuration of points and planes from the collection of point-to-plane distances. This problem models simultaneous localization and mapping from acoustic echoes as well as the & x201C;structure from sound & x201D; app ...

An indoor localization method for estimating the location of nodes (n1, n2), at least one node (n1) being connected to at least another node (n2) by at least two different channels (ch1, ch1′), comprising the following steps: measuring a distance between t ...

Shannon's separation theorem gives a conceptually and practically appealing way to construct an optimal communication system in two independent steps, namely source compression and channel coding. However, sometimes it is worth considering {\em joint} source/ channel coding instead. In fact, for certain source/channel pairs, not using any code at all already achieves the optimum performance. For a larger class

{\mathbb S}

of source/channel pairs, there exists a single-letter code with optimal performance.

In this article we present a novel approach of integrating textual and visual descriptors of images in a uniﬁed retrieval structure. The methodology, inspired from text retrieval and information ﬁltering is based on Latent Semantic Indexing (LS1).

Low-cost monitoring cameras/webcams provide unique visual information. To take advantage of the vast image dataset captured by a typical webcam, we consider the problem of retrieving weather information from a database of still images. The task is to autom ...

Tight Weyl–Heisenberg frames in l^2 (Z ) are the tool for short-time Fourier analysis in discrete time. They are closely related to paraunitary modulated filter banks and are studied here using techniques of the filter bank theory. Good resolution of short-time Fourier analysis in the joint time–frequency plane is not attainable unless some redundancy is introduced. That is the reason for considering overcomplete Weyl–Heisenberg expansions. The main result of this correspondence is a complete parameterizati

Martin Vetterli

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Wavelets and Subband Coding

Bound and Conquer: Improving Triangulation by Enforcing Consistency

Iterative Demosaicking Accelerated: Theory and Fast Noniterative Implementations

A Fast Hadamard Transform for Signals with Sub-linear Sparsity

Analysis of optimal filter banks for multiple description coding

On the Multiterminal Rate-Distortion Function for Acoustic Sensing

Distributed Sensing of Signals Linked by Sparse Filtering

Super Resolution Phase Retrieval for Sparse Signals

Calibration in Circular Ultrasound Tomography Devices

Sampling and reconstructing diffusion fields in presence of aliasing

Learning Network Structures from Firing Patterns

Distributed Compressed Sensing: Sparsity Models and Reconstruction Algorithms Using Annihilating Filter

The distributed Karhunen-Loeve transform

Rate-Constrained Beamforming for Collaborating Hearing Aids

Shapes From Echoes: Uniqueness From Point-to-Plane Distance Matrices

Indoor localization method and system

On optimal low-complexity source/channel coding

Joint Textual And Visual Cues For Retrieving Images Using Latent Semantic Indexing

How is the Weather: Automatic Inference from Images

Tight Weyl-Heisenberg frames in l2(Z)