KOR

e-Article

Locally-Rank-One-Based Joint Unmixing and Demosaicing Methods for Snapshot Spectral Images. Part I: A Matrix-Completion Framework
Document Type
Periodical
Source
IEEE Transactions on Computational Imaging IEEE Trans. Comput. Imaging Computational Imaging, IEEE Transactions on. 10:848-862 2024
Subject
Signal Processing and Analysis
Computing and Processing
General Topics for Engineers
Geoscience
Cameras
Hyperspectral imaging
Imaging
Spatial resolution
Fabry-Perot
Layout
Pipelines
Snapshot spectral imaging
unmixing
demosaicing
low-rank approximation
sparsity
Language
ISSN
2573-0436
2333-9403
2334-0118
Abstract
With the recent advancements in design and processing speed, a new snapshot mosaic imaging sensor architecture (SSI) has been successfully developed, holding the potential to transform the way dynamic scenes are captured using miniaturized platforms. However, SSI systems encounter a core trade-off concerning spatial and spectral resolution due to the assignment of individual spectral bands to each pixel. While the SSI camera manufacturer provides a pipeline to process such data, we propose in this paper to process the RAW SSI data directly. We show this strategy to be much more accurate than post-processing after the pipeline. In particular, in the first part of this paper, we propose a low-rank matrix factorization and completion framework which jointly tackles both the demosaicing and the unmixing steps of the SSI data. In addition to a “natural” technique, we expand the well-known pure pixel assumption to the SSI sensor level and propose two dedicated methods to extract the endmembers. The first one can be seen as a weighted Sparse Component Analysis (SCA) method, while the second one relaxes the abundance sparsity assumption of the former. The abundances are then recovered by applying the naive approach with the fixed extracted endmembers. Finally, we experimentally validate the merits of the proposed methods using synthetically generated data and real images obtained with an SSI camera.