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Hyperspectral imaging system calibration using image translations and
Fourier transform Nathalie Gorretta,a Gilles Rabatel,a Jean-Michel Roger,a Christophe Fiorio,b Camille
Lelongc and Veronique Bellon-Maurela aCemagref, UMR ITAP, 361 rue Jean-François Breton, F-34196 Montpellier, France.
E-mail: nathalie.gorretta@cemagref.fr bLIRMM, UMR 5506, Université Montpellier II, 161 rue Ada, F-34392 Montpellier Cedex 05,
France cCIRAD, UMR TETIS, 500 rue Jean-François Breton, F-34093 Montpellier, France
ABSTRACT:
In this paper, we describe a methodology based on
imaging system shifting and Fourier transform to recover the spatial distribution of the sensivity of a hyperspectral imaging system. The methodology mainly adresses a
hyperspectral imaging system based on a CCD sensor for proximity image acquisition. The principle is to look several times at the same scene by moving the camera slightly (a few
millimetres) at each acquisition. Thus, it is possible to separate what moves (scene) from what remains fixed (response of the system) using properties of Fourier transform. Tests
on synthetic images have reinforced theorical results on contraints shifts and given good results with more than ten translations. Tests on real and in-laboratory images have
shown the need for accurate determination of translation to avoid some disruptive effects (pattern multiplication). Nevertheless, the results are promising and have shown the
potential of the methodology to correct images from spatial non-uniformity due to the imaging system (radiometric aberration due to the sensor and optic). We notice that such a
methodology remains valid for any imaging system based on a charged-coupled device (CCD) sensor.
Keywords: hyperspectral imaging, Fourier transform, calibration
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