  Visual object tracking is an active topic in the computer vision domain with
applications extending over numerous fields. The main sub-tasks required to
build an object tracker (e.g. object detection, feature extraction and object
tracking) are computation-intensive. In addition, real-time operation of the
tracker is indispensable for almost all of its applications. Therefore,
complete hardware or hardware/software co-design approaches are pursued for
better tracker implementations. This paper presents a literature survey of the
hardware implementations of object trackers over the last two decades. Although
several tracking surveys exist in literature, a survey addressing the hardware
implementations of the different trackers is missing. We believe this survey
would fill the gap and complete the picture with the existing surveys of how to
design an efficient tracker and point out the future directions researchers can
follow in this field. We highlight the lack of hardware implementations for
state-of-the-art tracking algorithms as well as for enhanced classical
algorithms. We also stress the need for measuring the tracking performance of
the hardware-based trackers. Additionally, enough details of the hardware-based
trackers need to be provided to allow reasonable comparison between the
different implementations.
