Publication

Detecting salient cues through illumination-invariant color ratios

Journal Article (2004)

Journal

Robotics and Autonomous Systems

Pages

111-130

Volume

48

Number

2

Doc link

http://dx.doi.org/10.1016/j.robot.2004.06.003

File

Download the digital copy of the doc pdf document

Abstract

This work presents a novel technique for embedding color constancy into a saliency-based system for detecting potential landmarks in outdoor environments. Since multiscale color opponencies are among the ingredients determining saliency, the idea is to make such opponencies directly invariant to illumination variations, rather than enforcing the invariance of colors themselves. The new technique is compared against the alternative approach of preprocessing the images with a color constancy procedure before entering the saliency system. The first procedure used in the experimental comparison is the well-known image conversion to chromaticity space, and the second one is based on successive lighting intensity and illuminant color normalizations. The proposed technique offers significant advantages over the preceding two ones since, at a lower computational cost, it exhibits higher stability in front of illumination variations and even of slight viewpoint changes, resulting in a better correspondence of visual saliency to potential landmark elements.

Categories

pattern recognition.

Author keywords

visual landmarks, color constancy, visual saliency, visual robot navigation

Scientific reference

E. Todt and C. Torras. Detecting salient cues through illumination-invariant color ratios. Robotics and Autonomous Systems, 48(2): 111-130, 2004.