Phase-Based Disparity Estimation in Binocular Tracking

Abstract

: Binocular robots whose cameras can be independently directed require some mechanism for verging; i.e. aiming both cameras at a fixation point. Since the desired vergence angle is directly related to target distance, some sensory cue to give depth information is required to the vergence system. The estimation of binocular disparity is a fundamental precursor to the depth estimation. Algorithms using phase provide a new promising method for example based on the output of Gabor filters for disparity estimation. In this article, at first, we give a brief description of the phase-based algorithm, including an extension to handle the "wrap-around" problem, and a coarse-to-fine strategy "the hierarchical method with pixel-shift" is presented. For binocular tracking, computational time is restricted. Nevertheless, generally heavy calculations are required to get an output through Gabor filters. For that reason, a step-wise fast filter is examined and it is shown to be a substitute for the Ga...