With a spatial resolution of about 1 km at geostationary altitude and three spectral bands, visible, MR and SWIR, the CCD sensor of the Insat-2E satellite is the first of its kind used for meteorological applications. These CCD images contain up to 31 lines each composed of 7165 x 300-pixel high vertical frames. After launch, images were found to be contaminated with stray light from an unknown origin. As a result, there are strong false gradients between CCD lines and a deformation of the frame radiometric profiles depending on the general scene albedo. These artifacts adversely affect meteorological applications, in particular cloud motion wind vector determination and vegetation indexes. Because a full sensor technical description was unavailable, it was impossible to develop an analytical approach to assess possible causes. Instead, an empirical method was developed in order to reduce false gradients and excessive luminance. The proposed method had to be simple and fast for real time processing purposes.
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