Convolutional Sparse Representation of Injected Details for Pansharpening

In this letter, we address the pansharpening problem, which focuses on constructing a high-resolution (HR) multispectral (MS) image from a low-resolution (LR) MS and an HR panchromatic (Pan) image. The accuracy of pansharpening method based on sparse representation (SR) mainly depends on the construction of dictionary and the learning of sparse coefficients, while the details injection (DI)-based pansharpening method sharpens the MS bands by adding the proper spatial details from Pan. The combination of SR and DI has been put forward as the pansharpening method based on SR of injected details (SR-D). However, limited to the patch-based manner, pansharpening with traditional SR model faces two disadvantages, i.e., limited ability in detail preservation and high sensitivity to misregistration. In this letter, we replace the traditional SR model with convolutional SR (CSR) as a global SR model in the SR-D method and propose a new pansharpening method called CSR of injected details (CSR-D) to overcome the above-mentioned two drawbacks. Experimental results on the IKONOS and WorldView2 data sets show that the proposed method can achieve remarkable spectral and spatial quality on both reduced scale and full scale.