Multiband image fusion under spectrally varying spatial blurs — Application to JWST data

Multiband image fusion has been extensively studied in the literature of Earth observation. This task aims at recovering a multiband image of high spatial and high spectral resolutions from complementary measurements of lower spatial or spectral resolutions. While several methods developed in this context are able to fuse multiband images efficiently, they are not suitable to handle astronomical images, in particular in the context of observations made by the James Webb Space Telescope (JWST). Beyond the high dimensionality of the data, one major challenge lies in the operators associated with spatial blurs that should be considered as spectrally varying. This crucial issue significantly increases the complexity of the forward models and makes the state-of-the-art fusion methods inoperative. The main contributions reported in this talk tackle both challenges: a new framework is proposed to fuse large-scale astronomical data efficiently while taking into account the specificities of astronomical imaging.