A structure information based image fusion algorithm using IHS and discrete wavelet transform

Pixel-level image fusion, as an important part of image fusion algorithms, can combine spectral information of coarse resolution imagery with finer spatial resolution imagery. In this paper we propose a new pixel-level multisensor image fusion algorithm for sharpening multispectral (MS) data with better spectral preservation ability and higher spatial resolution combining intensity-hue-saturation (IHS) transformation and discrete wavelet transform (DWT) and develop a fusion rule based on structure information extracted from the high spatial resolution image. Experimental results are presented on a set of MS images and a Systeme Pour l’Observation de la Terre Panchromatic image. The proposed method was compared visually and qualitatively with existing standard IHS transformation, standard DWT strategies and a simple combination of IHS and DWT. Comparative analysis shows that the proposed algorithm has higher fidelity to the original spectral information and better spatial quality with respect to those methods for the test images.