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arXiv · 2504.20516

Spatial-enhanced Reflective Coded Aperture Snapshot Spectral Imaging

Abstract

Coded aperture snapshot hyperspectral imaging (CASSI) system which captures 2-D spatial information and 1-D spectral information in just one or two shots has become a promising technology to capture hyperspectral image (HSI). However, previous CASSI have shortcomings such as poor spatial resolution and low light efficiency that hinder their further applications. In this paper, we propose a spatial-enhanced reflective coded aperture snapshot spectral imaging system (SE-RCASSI). The system achieves superior spatial results and high light efficiency because of its specially designed structure. Then, we propose Spatial-enhanced Network (SEnet) which takes full use of the prior information of grayscale image to boost the reconstruction quality and can serve as an image fusion framework to deploy different algorithms. Furthermore, we propose hybrid prior strategy (HPS) to effectively exploit the broad-scope prior of training set and narrow-scope prior of measurements, resulting in improved generalization and performance of the network. Finally, we fabricate the prototype of SE-RCASSI and conduct experiments in different environments. Both experimental results and numerical simulations show the outstanding performance of our method.

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Jiayu Di, Yantao Jin, Zhenming Yu, Liming Cheng, Jingyue Ma, Ning Zhan, Kun Xu. 2025-04-29. Spatial-enhanced Reflective Coded Aperture Snapshot Spectral Imaging. https://arxiv.org/abs/2504.20516

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