Assessment of different topographic corrections in AWiFS satellite imagery of Himalaya terrain

The influence of topographic effects in optical satellite imagery is not investigated very extensively in the Himalayan terrain. The topographic variability causes a problem of differential illumination due to steep and varying slopes in rugged Himalayan terrain. Therefore, topographic corrections are essential for qualitative and quantitative analysis of snow cover applications. The present paper discusses the implementation of different topographic correction models on AWiFS sensor onboard IRS P6 satellite images and the qualitative and quantitative comparative analysis in detail. Both the Lambertian and non-Lambertian assumptions have been considered in the present analysis with the aim to explore best suitable empirical model for rugged terrain. The main topographic methods implemented are: • C-correction • Minneart corrections • Civco’s modified version of cosine correction • two-stage normalization and • slope matching technique.