Pansharpening Through Proportional Detail Injection Based on Generalized Relative Spectral Response

In this letter, we propose a novel pansharpening method which enhances the spatial resolution of low-spatial-resolution multispectral (MS) images through proportional detail injection (PDI) based on the generalized relative spectral response (GRSR). In the algorithm, the spatial details are extracted as the difference between the panchromatic (PAN) image and the resampled low-resolution PAN image. Then, the spatial details are further modulated and injected into each band of the resampled MS image according to the proportion of the intensity of the low-frequency component of each band to the offset-removed synthetic intensity component obtained according to the GRSR. Both quantitative and qualitative evaluations demonstrate the superiority of the proposed method in terms of spatial enhancement, spectral fidelity, and computational complexity.