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arXiv · 1801.09343

KRISM --- Krylov Subspace-based Optical Computing of Hyperspectral Images

Vishwanath Saragadam·Aswin C. Sankaranarayanan
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Abstract

We present an adaptive imaging technique that optically computes a low-rank approximation of a scene's hyperspectral image, conceptualized as a matrix. Central to the proposed technique is the optical implementation of two measurement operators: a spectrally-coded imager and a spatially-coded spectrometer. By iterating between the two operators, we show that the top singular vectors and singular values of a hyperspectral image can be adaptively and optically computed with only a few iterations. We present an optical design that uses pupil plane coding for implementing the two operations and show several compelling results using a lab prototype to demonstrate the effectiveness of the proposed hyperspectral imager.

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Vishwanath Saragadam, Aswin C. Sankaranarayanan. 2018-01-26. KRISM --- Krylov Subspace-based Optical Computing of Hyperspectral Images. https://doi.org/10.1145/3345553

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