Riccardo March

Variational Models for Image Colorization via Chromaticity and Brightness Decomposition

Colorization refers to an image processing task which recovers color in grayscale images when only small regions with color are given. We propose a couple of variational models using chromaticity color components to colorize black and white images. We first consider total variation minimizing (TV) colorization which is an extension from TV inpainting to color using chromaticity model. Second, we further modify our model to weighted harmonic maps for colorization. This model adds edge information from the brightness data, while it reconstructs smooth color values for each homogeneous region. We introduce penalized versions of the variational models, we analyze their convergence properties, and we present numerical results including extension to texture colorization.

AN IMAGE SEGMENTATION VARIATIONAL MODEL WITH FREE DISCONTINUITIES AND CONTOUR CURVATURE

We introduce a functional for image segmentation which takes into account the transparencies (or shadowing) and the occlusions between objects located at different depths in space. By minimizing the functional, we try to reconstruct a piecewise smooth approximation of the input image, the contours due to transparencies, and the contours of the objects together with their hidden portions. The functional includes a Mumford–Shah type energy and a term involving the curvature of the contours. The variational properties of the functional are studied, as well as its approximation by Γ-convergence. The comparison with the Nitzberg–Mumford variational model for segmentation with depth is also discussed.

Solar System constraints to nonminimally coupled gravity

We extend the analysis of Chiba, Smith and Erickcek \cite{CSE} of Solar System constraints on

Perturbation of the metric around a spherical body from a nonminimal coupling between matter and curvature

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Surface analysis of stone materials integrating spatial data and computer vision techniques

gravity to a class of nonminimally coupled (NMC) theories of gravity. These generalize

Variational Properties of a Model for Image Segmentation with Overlapping Regions

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Numerical analysis of oscillations in a nonconvex problem related to image selective smoothing

theories by replacing the action functional of General Relativity (GR) with a more general form involving two functions

Multiphase image segmentation via equally distanced multiple well potential

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1/c expansion of nonminimally coupled curvature-matter gravity models and constraints from planetary precession

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Asymptotic Properties of the Nitzberg-Mumford Variational Model for Segmentation with Depth

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