Calculus of Variations and Geometric Measure Theory

M. Gobbino - N. Picenni

A quantitative variational analysis of the staircasing phenomenon for a second order regularization of the Perona-Malik functional

created by picenni on 11 Apr 2023
modified on 30 Oct 2023

[BibTeX]

Published Paper

Inserted: 11 apr 2023
Last Updated: 30 oct 2023

Journal: Trans. Amer. Math. Soc.
Year: 2023
Doi: https://doi.org/10.1090/tran/8841

ArXiv: 2205.02467 PDF

Abstract:

We consider the Perona-Malik functional in dimension one, namely an integral functional whose Lagrangian is convex-concave with respect to the derivative, with a convexification that is identically zero. We approximate and regularize the functional by adding a term that depends on second order derivatives multiplied by a small coefficient. We investigate the asymptotic behavior of minima and minimizers as this small parameter vanishes. In particular, we show that minimizers exhibit the so-called staircasing phenomenon, namely they develop a sort of microstructure that looks like a piecewise constant function at a suitable scale. Our analysis relies on Gamma-convergence results for a rescaled functional, blow-up techniques, and a characterization of local minimizers for the limit problem. This approach can be extended to more general models.