Large-Displacement 3D Object Tracking with Hybrid Non-local Optimization
"Optimization-based 3D object tracking is known to be precise and fast, but sensitive to large inter-frame displacements due to the local minimum, which usually requires large amount of computation to be overcome. In this paper we propose a fast and effective non-local 3D tracking method. Based on the observation that local minimum are mostly due to the out-of-plane rotation, we propose a hybrid approach combining non-local and local optimizations for different parameters, resulting in efficient non-local search in the 6D pose space. In addition, a precomputed robust contour-based tracking method is proposed for the local optimization. By using long search lines with multiple candidate correspondences, it can better adaptive to different frame displacements without the need of coarse-to-fine search. After the pre-computation, pose updates can be conducted very fast, enabling the non-local optimization in real time. Our method outperforms all previous methods for both small and large displacements. For large displacements, the accuracy is greatly improved (81.7% v.s.19.4%). At the same time, real-time speed (>50fps) can be achieved with only CPU.The source code is available at https://github.com/cvbubbles/nonlocal-3dtracking."