Hierarchical Context Measurement Network for Single Hyperspectral Image Super-Resolution

Single hyperspectral image super-resolution aims to enhance the spatial resolution of a hyperspectral image without relying on any auxiliary information. Despite the abundant spectral information, the inherent high-dimensionality in hyperspectral images still remains a challenge for memory efficiency. Recently, recursion-based methods have been proposed to reduce memory requirements. However, these methods utilize the reconstruction features as feedback embedding to explore context information, leading to sub-optimal performance as they ignore the complementarity of different hierarchical levels of information in the context. Additionally, existing methods equivalently compensate the previous feedback information to the current band, resulting in an indistinct and untargeted introduction of the context. In this paper, we propose a hierarchical context measurement network to construct corresponding measurement strategies for different hierarchical information, capturing comprehensive and powerful complementary knowledge from the context. Specifically, a feature-wise similarity measurement module is designed to calculate global cross-layer relationships between the middle features of the current band and those of the context, so as to explore the embedded middle features discriminatively through generated global dependencies. Furthermore, considering the pixel-wise correspondence between the reconstruction features and the super-resolved results, we propose a pixel-wise similarity measurement module for the complementary reconstruction features embedding, exploring detailed complementary information within the embedded reconstruction features by dynamically generating a spatially adaptive filter for each pixel. Experimental results reported on three benchmark hyperspectral datasets reveal that the proposed method outperforms other state-of-the-art peers in both visual and metric evaluations.