Published
Spectral resolution enhancement of hyperspectral imagery by a multiple-aperture compressive optical imaging system
Mejoramiento de la resolución espectral de imágenes hiperespectrales, por medio de un sistema óptico compresivo de múltiple-apertura
Keywords:
Hyperspectral imaging, Resolution enhancement, Compressive sensing, Coded aperture (en)imágenes hiperespectrales, mejora de resolución espectral, sensado compresivo, apertura codificada (es)
The Coded Aperture Snapshot Spectral Imaging (CASSI) system captures the three-dimensional (3D) spatio-spectral information of a scene using a set of two-dimensional (2D) random-coded Focal Plane Array (FPA) measurements. A compressive sensing reconstruction algorithm is then used to recover the underlying spatio-spectral 3D data cube. The quality of the reconstructed spectral images depends exclusively on the CASSI sensing matrix, which is determined by the structure of a set of random coded apertures. In this paper, the CASSI system is generalized by developing a multiple-aperture optical imaging system such that spectral resolution enhancement is attainable. In the proposed system, a pair of high-resolution coded apertures is introduced into the CASSI system, allowing it to encode both spatial and spectral characteristics of the hyperspectral image. This approach allows the reconstruction of super-resolved hyperspectral data cubes, where the number of spectral bands is significantly increased and the quality in the spatial domain is greatly improved. Extensively simulated experiments show a gain in the peak-signal-to-noise ratio (PSNR), along with a better fit of the reconstructed spectral signatures to the original spectral data.
El sistema de sensado de imágenes espectrales, basado en la apertura codificada y de única toma (CASSI), captura la información espacial y espectral de una escena; mediante mediciones codificadas aleatorias capturadas en un sensor 2D. Un algoritmo basado en la teoría de sensado compresivo (CS), es utilizado para recuperar la escena tridimensional original a partir de las mediciones aleatorias capturadas. La calidad de reconstrucción de la escena depende exclusivamente, de la matriz de sensado del CASSI, la cual es determinada por la estructura de las aperturas codificadas que son utilizadas. En este artículo, se propone una generalización del sistema CASSI por medio del desarrollo de un sistema óptico multi-apertura, que permite el mejoramiento de la resolución espectral. En el sistema propuesto, un par de aperturas codificadas de alta resolución es introducido en el sistema CASSI, permitiendo así, la codificación tanto espacial como espectral de la imagen hiperespectral. Este enfoque permite la reconstrucción de cubos de datos hiperespectrales, donde el número de las bandas espectrales se aumenta significativamente respecto al original, y la calidad espacial es mejorada en gran medida. Así mismo, los experimentos simulados muestran mejoramiento en la relación de pico-de-señal-a-ruido (PSNR), junto con un mejor ajuste en las firmas espectrales reconstruidas sobre los datos espectrales originales.
References
Arce, G. R., Brady, D. J., Carin, L., Arguello, H., & Kittle D. S. (2014). An introduction to compressive coded aperture spectral imaging. IEEE Signal Processing Magazine, 31(1), 105-115.
Arguello, H., & Arce, G. R. (2011). Code aperture optimization for spectrally agile compressive imaging. JOSA A, 28(11), 2400-2413.
Arguello, H., & Arce, G. R. (2013). Rank minimization code aperture design for spectrally selective compressive imaging. IEEE Transactions on Image Processing, 22(3), 941-954.
Arguello, H., Correa, C., & Arce, G. R. (2013). Fast lapped block reconstructions in compressive spectral imaging. Applied Optics, 52(10), D32 - D45.
Arguello, H., Rueda, H., & Arce, G. R. (2013). Higher-order computational model for coded aperture spectral imaging. Applied Optics, 52(10), D12 - D21.
Brady, D. J. (2009). Optical Imaging and Spectroscopy. Wiley, John and Sons.
Candès, E., & Tao, T. (2006). Near-optimal signal recovery from random projections: Universal encoding strategies? IEEE Transactions on Information Theory, 52(12), 5406-5425.
Donoho, D. L. (2006). Compressed sensing. IEEE Transactions on Information Theory, 52(4), 1289-1306.
Eismann, M. (2012). Hyperspectral Remote Sensing. SPIE Press.
Figueiredo, M. A. T., Nowak, R. D., & Wright, S. J. (2007). Gradient projection for sparse reconstruction: Application to compressed sensing and other inverse problems. IEEE Journal of Selected Topics in Signal Processing, 1(4), 586-597.
Wagadarikar, A. A., John, R., Willett, R., & Brady, D. (2008). Single disperser design for coded aperture snapshot spectral imaging. Applied Optics, 47(10), B44-B51.
Willett, R. M., Marcia, R. F., & Nichols, J. M. (2011). Compressed sensing for practical optical imaging systems: a tutorial. Optical Engineering, 50(7), 072601-1 - 072601-13.
License
Copyright (c) 2014 Hoover Fabian Rueda Chacon, Alejandro Parada Mayorga, Henry Arguello Fuentes
This work is licensed under a Creative Commons Attribution 4.0 International License.
The authors or holders of the copyright for each article hereby confer exclusive, limited and free authorization on the Universidad Nacional de Colombia's journal Ingeniería e Investigación concerning the aforementioned article which, once it has been evaluated and approved, will be submitted for publication, in line with the following items:
1. The version which has been corrected according to the evaluators' suggestions will be remitted and it will be made clear whether the aforementioned article is an unedited document regarding which the rights to be authorized are held and total responsibility will be assumed by the authors for the content of the work being submitted to Ingeniería e Investigación, the Universidad Nacional de Colombia and third-parties;
2. The authorization conferred on the journal will come into force from the date on which it is included in the respective volume and issue of Ingeniería e Investigación in the Open Journal Systems and on the journal's main page (https://revistas.unal.edu.co/index.php/ingeinv), as well as in different databases and indices in which the publication is indexed;
3. The authors authorize the Universidad Nacional de Colombia's journal Ingeniería e Investigación to publish the document in whatever required format (printed, digital, electronic or whatsoever known or yet to be discovered form) and authorize Ingeniería e Investigación to include the work in any indices and/or search engines deemed necessary for promoting its diffusion;
4. The authors accept that such authorization is given free of charge and they, therefore, waive any right to receive remuneration from the publication, distribution, public communication and any use whatsoever referred to in the terms of this authorization.
