IEEE Trans Image Process. 2018 Sep;27(9):4478-4489. doi: 10.1109/TIP.2018.2839916.
Sparse representation has been widely exploited to develop an effective appearance model for object tracking due to its well discriminative capability in distinguishing the target from its surrounding background. However, most of these methods only consider either the holistic representation or the local one for each patch with equal importance, and hence may fail when the target suffers from severe occlusion or large-scale pose variation. In this paper, we propose a simple yet effective approach that exploits rich feature information from reliable patches based on weighted local sparse representation that takes into account the importance of each patch. Specifically, we design a reconstruction-error based weight function with the reconstruction error of each patch via sparse coding to measure the patch reliability. Moreover, we explore spatio-temporal context information to enhance the robustness of the appearance model, in which the global temporal context is learned via incremental subspace and sparse representation learning with a novel dynamic template update strategy to update the dictionary, while the local spatial context considers the correlation between the target and its surrounding background via measuring the similarity among their sparse coefficients. Extensive experimental evaluations on two large tracking benchmarks demonstrate favorable performance of the proposed method over some state-of-the-art trackers.
稀疏表示由于其在区分目标与其周围背景方面具有良好的判别能力,因此被广泛用于开发有效的目标跟踪外观模型。然而,这些方法中的大多数仅考虑每个补丁的整体表示或局部表示,同等重要,因此当目标受到严重遮挡或大的姿态变化时,可能会失败。在本文中,我们提出了一种简单而有效的方法,该方法利用基于加权局部稀疏表示的可靠补丁中的丰富特征信息,考虑每个补丁的重要性。具体来说,我们设计了一种基于重构误差的权重函数,该函数通过稀疏编码来测量每个补丁的重构误差,以衡量补丁的可靠性。此外,我们还探索了时空上下文信息,以增强外观模型的鲁棒性,其中全局时空上下文通过增量子空间和稀疏表示学习来学习,具有新颖的动态模板更新策略来更新字典,而局部空间上下文则通过测量稀疏系数之间的相似性来考虑目标与其周围背景之间的相关性。在两个大型跟踪基准上的广泛实验评估表明,该方法优于一些最先进的跟踪器。