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arXiv · 2410.18691

Hyperspectral Spatial Super-Resolution using Keystone Error

Ankur Garg·Meenakshi Sarkar·S. Manthira Moorthi·Debajyoti Dhar
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Abstract

Hyperspectral images enable precise identification of ground objects by capturing their spectral signatures with fine spectral resolution.While high spatial resolution further enhances this capability, increasing spatial resolution through hardware like larger telescopes is costly and inefficient. A more optimal solution is using ground processing techniques, such as hypersharpening, to merge high spectral and spatial resolution data. However, this method works best when datasets are captured under similar conditions, which is difficult when using data from different times. In this work, we propose a superresolution approach to enhance hyperspectral data's spatial resolution without auxiliary input. Our method estimates the high-resolution point spread function (PSF) using blind deconvolution and corrects for sampling-related blur using a model-based superresolution framework. This differs from previous approaches by not assuming a known highresolution blur. We also introduce an adaptive prior that improves performance compared to existing methods. Applied to the visible and near-infrared (VNIR) spectrometer of HySIS, ISRO hyperspectral sensor, our algorithm removes aliasing and boosts resolution by approximately 1.3 times. It is versatile and can be applied to similar systems.

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Ankur Garg, Meenakshi Sarkar, S. Manthira Moorthi, Debajyoti Dhar. 2024-10-24. Hyperspectral Spatial Super-Resolution using Keystone Error. https://arxiv.org/abs/2410.18691

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