Restoration of Pansharpened Images by Conditional Filtering in the PCA Domain

Pansharpening techniques aim at fusing a low-spatial resolution multispectral (MS) image with a higher spatial resolution panchromatic (PAN) image to produce an MS image at high spatial resolution. Despite significant progress in the field, spectral and spatial distortions might still compromise the quality of the results. We introduce a restoration strategy to mitigate artifacts of fused products. After applying the principal component analysis transform to a pansharpened image, the chromatic components are filtered conditionally to the geometry of PAN. The structural component is then replaced by the locally histogram-matched PAN for spatial enhancement. Experimental results illustrate the efficiency of the proposed restoration chain.