Visual tracking and segmentation using appearance and spatial information of patches

Object tracking and segmentation find a wide range of applications in robotics. Tracking and segmentation are difficult in cluttered and dynamic backgrounds. We propose a tracking and segmentation algorithm in which tracking and segmentation are performed consecutively. We separate input images into disjoint patches using an efficient oversegmentation algorithm. Objects and their background are described by bags of patches. We classify the patches in a new frame by searching k nearest neighbors. K-d trees are constructed using these patches to reduce computational complexity. Target location is estimated coarsely by running the mean-shift algorithm. Based on the estimated locations, we classify the patches again using appearance and spatial information. This strategy out-performs direct segmentation of patches based on appearance information only. Experimental results show that the proposed algorithm provides good performance on difficult sequences with clutter.