SiamOHOT: A Lightweight Dual Siamese Network for Onboard Hyperspectral Object Tracking via Joint Spatial-Spectral Knowledge Distillation

Hyperspectral object tracking is aimed at tracking targets by using both spatial information and abundant spectral information, overcoming the drawbacks of traditional RGB tracking in complex scenarios, such as low resolution or background clutter. However, the current hyperspectral object tracking methods usually have a high computational complexity, due to the huge data volume, making them difficult to apply to real-time applications on edge devices (e.g., robots, unmanned aerial vehicles, and satellites) with limited computational resources. In this article, a lightweight dual Siamese network for onboard hyperspectral object tracking—termed SiamOHOT—is proposed for real-time and onboard tracking. Specifically, a joint spatial-spectral knowledge distillation method is proposed to teach a lightweight dual Siamese tracker to learn from a deep tracker—SiamHYPER—so that the number of parameters can be compressed to improve the computational efficiency. In addition, a deep learning inference optimizer is introduced to fuse the layers with similar functions and quantify the parameters of the network, to further promote the processing speed when deployed on an embedded platform. The proposed lightweight model was verified using the 2021 WHISPERS Hyperspectral Object Tracking Challenge dataset, and achieved a superior efficiency and accuracy. In addition, a prototype system was built integrating a snapshot hyperspectral imager, the SiamOHOT tracking algorithm, and an artificial intelligence edge device (NVIDIA Jetson Xavier NX), to realize real-time imaging and tracking. The inference speed of the optimized SiamOHOT network is nearly doubled when compared to the teacher model on the prototype system.