Illumination insensitive efficient second-order minimization for planar object tracking

Tracking for planar objects is an important issue to vision-based robotic applications. In direct visual tracking (DVT) methods, the similarity between two images is often measured through the sum of squared differences (SSD) especially with the efficient second-order minimization (ESM) due to its simplicity and efficiency. However, SSD-based ESM is not robust to illumination changes since it is usually built upon the brightness constancy assumption. Contrast to image brightness, gradient orientations (GO) are invariant to both linear and non-linear illumination changes as verified in practice. Based on GO, we propose an illumination insensitive ESM method for planar object tracking in this paper. In order to introduce GO into the ESM, we generalized the original ESM formulas for multi-dimensional features. In addition, a denoising method based on the Perona-Malik function and a mask image were suggested to improve GO's robustness against image noise and low texture. Our experimental results on dataset for planar objects with illumination changes and a benchmark dataset confirm the proposed method is robust to illumination variations and capable to deal with the general tracking challenges.