Bilateral filters: what they can and cannot do

TL;DR

This paper explores the fundamental properties and limitations of nonlinear bilateral filters, explaining their denoising mechanism and providing guidelines for optimal parameter selection, with practical application to CT image noise reduction.

Contribution

It offers a detailed analysis of bilateral filters' behavior, clarifies their noise suppression capabilities, and proposes a methodology for choosing optimal filter parameters.

Findings

Bilateral filters effectively denoise images while preserving edges.

The paper identifies limitations in bilateral filter performance.

A practical method for optimal parameter selection is proposed.

Abstract

Nonlinear bilateral filters (BF) deliver a fine blend of computational simplicity and blur-free denoising. However, little is known about their nature, noise-suppressing properties, and optimal choices of filter parameters. Our study is meant to fill this gap-explaining the underlying mechanism of bilateral filtering and providing the methodology for optimal filter selection. Practical application to CT image denoising is discussed to illustrate our results.