Visual object tracking, which is representing a major interest in image processing field, has facilitated numerous real world applications. Among them, equipping unmanned aerial vehicle (UAV) with real time robust visual trackers for all day aerial maneuver, is currently attracting incremental attention and has remarkably broadened the scope of applications of object tracking. However, prior tracking methods have merely focused on robust tracking in the well-illuminated scenes, while ignoring trackers' capabilities to be deployed in the dark. In darkness, the conditions can be more complex and harsh, easily posing inferior robust tracking or even tracking failure. To this end, this work proposed a novel discriminative correlation filter based tracker with illumination adaptive and anti dark capability, namely ADTrack. ADTrack firstly exploits image illuminance information to enable adaptability of the model to the given light condition. Then, by virtue of an efficient and effective image enhancer, ADTrack carries out image pretreatment, where a target aware mask is generated. Benefiting from the mask, ADTrack aims to solve a dual regression problem where dual filters, i.e., the context filter and target focused filter, are trained with mutual constraint. Thus ADTrack is able to maintain continuously favorable performance in all-day conditions. Besides, this work also constructed one UAV nighttime tracking benchmark UAVDark135, comprising of more than 125k manually annotated frames, which is also very first UAV nighttime tracking benchmark. Exhaustive experiments are extended on authoritative daytime benchmarks, i.e., UAV123 10fps, DTB70, and the newly built dark benchmark UAVDark135, which have validated the superiority of ADTrack in both bright and dark conditions on a single CPU.

中文翻译：

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无人机全天目标跟踪

视觉对象跟踪代表了图像处理领域的主要兴趣，它促进了许多实际应用。其中，为无人驾驶飞机（UAV）配备用于全天空中机动的实时鲁棒视觉跟踪器，目前正引起越来越多的关注，并显着扩大了对象跟踪的应用范围。但是，现有的跟踪方法仅专注于在照亮的场景中进行稳健的跟踪，而忽略了跟踪器在黑暗中的部署能力。在黑暗中，情况可能更复杂，更苛刻，容易造成较差的鲁棒跟踪甚至跟踪失败。为此，这项工作提出了一种新颖的基于判别相关滤波器的跟踪器，该跟踪器具有光照自适应和抗暗功能，即ADTrack。ADTrack首先利用图像照度信息来使模型适应给定的光照条件。然后，借助高效有效的图像增强器，ADTrack进行图像预处理，从而生成目标感知掩模。得益于掩码，ADTrack旨在解决双重回归问题，其中双重过滤器（即上下文过滤器和目标聚焦过滤器）在相互约束下进行训练。因此，ADTrack能够在全天条件下保持持续良好的性能。此外，这项工作还构建了一个无人机夜间跟踪基准UAVDark135，其中包括超过125k的手动注释帧，这也是第一个无人机夜间跟踪基准。详尽的实验在权威的白天基准（即UAV123 10fps，DTB70，