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Hyperspectral imaging system calibration using image translations and Fourier transform

Gorretta N., Rabatel G., Roger J.M., Fiorio C., Lelong C., Bellon-Maurel V.. 2008. Journal of Near Infrared Spectroscopy, 16 (4) : p. 371-380.

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. (Résumé d'auteur)

Mots-clés : imagerie; méthodologie; normalisation; analyse d'image; modèle mathématique

Thématique : Méthodes de relevé; Méthodes mathématiques et statistiques

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