Pan-sharpening based on improvement of panchromatic image to minimize spectral distortion

In this paper, we propose a novel method to enhance the pan-sharpening result of low-resolution multispectral images (MS) and high-resolution panchromatic images (Pan) by minimizing the spectral distortion engendered by the fusion process. In fact, spectral distortion is the most significant problem in many pansharpening techniques, due to the non linearity between Pan and MS images. In this method, an improvement of the Pan image is performed in order to enhance the correlation between Pan and MS images before pan-sharpening process. The proposed method is applied as a preprocessing by fusing the intensity image derived from MS image with the original Pan to get an improved Pan image which could be more correlated with MS image. And later, the pan-sharpening is applied on both MS and the improved Pan using any pan-sharpening technique. Simulation results of proposed method are compared in four different techniques, such as: Generalized IHS, DWT, Brovey and HPF. It has been observed that simulation results of this method preserves more spectral information and gets better visual quality compared with earlier reported techniques using original Pan.