Low-Rank Prompt-Guided Transformer for Hyperspectral Image Denoising
Xiaodong Tan, Mingwen Shao, Yuanjian Qiao, Tiyao Liu, Xiangyong Cao
Abstract
Hyperspectral image (HSI) denoising is an essential preprocessing step for downstream applications. Although vision transformer (ViT)-based approaches show impressive denoising performance through self-similarity modeling, these methods still fail to exploit spatial and spectral correlations while ensuring flexibility and efficacy. To address this issue, we propose a hyperspectral denoising transformer using low-rank prompt (HyLoRa), simultaneously taking the spatial self-similarity and spectral low-rank property into account for HSI denoising. Specifically, to fully utilize intrinsic similarity in spatial domain, we perform cross-shaped window-based spatial self-attention for effectively modeling local and global similarity. Moreover, to exploit low-rank inductive bias, we integrate a low-rank prompt module into attention calculation for counting corrected low-dimensional vectors from a large collection of HSIs. This helps to better refine underlying noise-free structure representations. Compared to existing works, powerful capabilities for modeling spatial and spectral correlations can be built to correct low-rank representation in the feature space. Extensive experiments on both simulated and real remote sensing noise demonstrate that our HyLoRa consistently surpasses the state-of-the-art methods.