Enhanced vegetation index of THEOS imagery by pan-sharpening

Remote sensing based mapping of various kinds and heterogeneous vegetation areas requires high resolution images for better understanding of the observed earth surface. Pan-sharpening is a useful technique for combining a high resolution panchromatic (HRPan) image with a low resolution multispectral (LRMs) image to synthesize a high resolution multispectral (HRMs) image. There are various data fusion methods for pansharpening satellite images. However, these methods always introduce spectral and spatial distortions, particularly in vegetated areas; therefore a designing mixing rule of the fusion method is required. This paper proposes tuning intensity-hue-saturation and Brovey transforms (IHS-BT) fusion technique to enhance vegetation index of THEOS (THailand Earth Observation System) imagery. The results were compared both qualitatively and quantitatively by using spectral and spatial error metrics. This research concludes that tuning IHS-BT performed quite well and will be a valuable technique for enhancing images for vegetation analysis.