Exposure Adjustment for Hyperspectral Cameras

In this paper we present a simple method to adjust the exposure of a hyper-spectral camera. As hyper-spectral cameras capture images over multiple wavelength-indexed bands, exposure control techniques used for tri-chromatic sensors do not often extend to hyper-spectral imagers. Here, we aim at estimating the exposure time for every wavelength channel by capturing an initial view of the scene. We then apply contrast adjustment techniques to this view of the scene so as to recover a reference cumulative distribution function (CDF) of the image brightness at each band. This CDF can then are used to calculate the new exposure time for every wavelength channel. We illustrate the utility of our method for exposure control and explore its stability with respect to both, a uniform and a Gaussian cumulative distribution functions.