ABSTRACT
A conspicuous number of image fusion methods proposed in the literature exploits a spectral transformation of the low-resolution multispectral (MS) bands. After interpolating, and possibly coregistering, whenever necessary, the MS data at the scale of the Pan image, a spectral transformation of MS pixels is performed, a main component, which must be nonnegative, is replaced with the Pan image, and the inverse spectral transformation yields the sharpened MS bands. Before the substitution, the Pan image is histogram matched to the selected component, which will be denoted as intensity component, in order to increase its spectral matching. As will be demonstrated in the following sections in this chapter, this operation is equivalent to inserting the dierence between the histogram-matched Pan and the intensity component into the interpolated MS bands to produce the sharpened MS bands [26].
