Pipeline-Centered Neighboring Network for Deep Unfolding Pansharpening

Pansharpening technique is dedicated to enriching the spatial details of low-resolution multispectral images (LRMS) under the guidance of a panchromatic (PAN) image. With the guarantee of promising results, Transformer-based methods have enjoyed a high reputation in this field. However, to reduce computational cost, existing solutions typically divide images into smaller, independent windows, which often weakens inter-window and channel-wise interactions as well as leads to unsmooth edges. To address these issues, we first formulate the pansharpening task as a variational optimization problem, and subsequently solve its data and prior subproblems alternately through an unrolling algorithm. In the prior extractor, we propose a Pipeline-Centered Neighboring Attention (PCNA), which holistically allows all pixels to share the same attention span while fully leveraging channel dependencies, thereby significantly improving the capability to process multispectral images. Moreover, a Multi-Scale Channel-Aware (MSCA) module is designed to capture the edges and structural details. Finally, by sequentially integrating the data and prior modules at each iteration stage, we unroll the iterations into a stage-wise unfolding network. Extensive experiments on three satellite datasets demonstrate the effectiveness and efficiency of our proposal compared to cutting-edge methods.