Application of fractional-order differentiation in multispectral image fusion

In this letter, a novel pansharpening method is proposed using component substitution (CS) framework. In order to inject the spatial details into the low resolution multispectral (MS) bands, the fractional-order differentiation is used. Eight direction masks are superimposed on each other to construct a unique mask. The primitive detail map is calculated using the difference between the panchromatic (PAN) image and a linear combination of the low resolution MS bands. To refine the detail map and better pansharpening, the superimposed mask is convolved with the extracted primitive detail map. Two datasets collected by the WorldView-2 and Pleiades satellites are used to examine the proposed method. Experimental results show that in comparison with the state-of-the-art methods, the proposed method can better provide the spectral and spatial information in the fused product quantitatively and subjectively.