The inversion of the one-dimensional Radon transform on the rotation group SO(3) is an ill-posed inverse problem that can be applied to X-ray tomography with polycrystalline materials. This paper is concerned with the development of a method to stably approximate the inverse of the noisy Radon transform on SO(3). The proposed approach is composed by basic building blocks of the coorbit theory o...

A monocular boundary contour (MBC) rivalry stimulus has two half-images, a homogeneous grating and the same homogeneous grating with an additional disc region. The outline/frame of the MBC disc is created by relative phase-shift, or orientation-difference. We found the increment contrast threshold and reaction time to detect a monocular Gabor probe elevated on the homogeneous half-image pedesta...

Stereoacuity improves with increasing contrast, unless the increase is monocular. In this case performance paradoxically suffers. This study examined whether this contrast paradox occurs for two other classes of visual judgment: two-frame motion and vernier acuity. We constructed three homologous tasks in which the two components of a gabor stimulus (stereo half-images, motion frames, vernier c...

In this work, we present a system for the automated classification of seabed substrates in underwater video. Classification of seabed substrates traditionally requires manual analysis by a marine biologist, according to an established classification system. Accurate, consistent and robust classification is difficult in underwater video due to varying lighting conditions, turbidity and method of...

In this paper we integrate several spatial texture tools into a texturebased video coding scheme. We implemented texture feature techniques such as Gabor filters and the Gray Level Co-occurrence matrix in combination with two segmentation strategies, namely the split and merge algorithm and clustering techniques, in order to detect texture regions in video sequences. These textures are analyzed...

Abstract. This paper introduces the concept of Bessel and frame multipliers. These operators are defined by a fixed pattern, called the symbol, which is used after analysis, before synthesis. This concept is a generalization of Gabor multipliers. It allows specialization to any analysis/synthesis systems, that form Bessel sequences, like e.g. wavelet frames. Basic properties of this general cla...

Starting from a general operator representation in the time-frequency domain, this paper addresses the problem of approximating linear operators by operators that are diagonal or band-diagonal with respect to Gabor frames. A characterization of operators that can be realized as Gabor multipliers is given and necessary conditions for the existence of (Hilbert-Schmidt) optimal Gabor multiplier ap...

An elementary function that is now commonly referred to Gabor function, Gabor filter and Gabor wavelet was derived from uncertainty relation for information by Gabor to overcome the representation limit of Fourier analysis. Analyzing a signal by a Gabor filter in terms of convolution or spatial filtering, two pieces of information—phase and magnitude—can be obtained. In the paper, Gabor filter ...

Frames are the foundation of the linear operators used in the decomposition and reconstruction of signals, such as the discrete Fourier transform, Gabor, wavelets, and curvelet transforms. The emergence of sparse representation models has shifted of the emphasis in frame theory toward sparse l1-minimization problems. In this paper, we apply frame theory to the sparse representation of signals i...

We analyze the interplay between contact geometry and Gabor filters signal analysis in geometric models of primary visual cortex. show particular that a specific framed lattice an associated system is determined by Legendrian circle bundle structure $3$-manifold elements on surface (which V1-cortex), together with presence almost-complex tangent retinal surface). identify scaling lattice, also ...