Central Pixel-Based Dual-Branch Network for Hyperspectral Image Classification

Hyperspectral image classification faces significant challenges in effectively extracting and integrating spectral-spatial features from high-dimensional data. Recent deep learning (DL) methods combining Convolutional Neural Networks (CNNs) and Vision Transformers (ViTs) have demonstrated exceptional performance. However, two critical challenges may cause degradation in the classification accuracy of these methods: interference from irrelevant information within the observed region, and the potential loss of useful information due to local spectral variability within the same class. To address these issues, we propose a central pixel-based dual-branch network (CPDB-Net) that synergistically integrates CNN and ViT for robust feature extraction. Specifically, the central spectral feature extraction branch based on CNN serves as a strong prior to reinforce the importance of central pixel features in classification. Additionally, the spatial branch based on ViT incorporates a novel frequency-aware HiLo attention, which can effectively separate high and low frequencies, alleviating the problem of local spectral variability and enhancing the ability to extract global features. Extensive experiments on widely used HSI datasets demonstrate the superiority of our method. Our CPDB-Net achieves the highest overall accuracies of 92.67%, 97.48%, and 95.02% on the Indian Pines, Pavia University, and Houston 2013 datasets, respectively, outperforming recent representative methods and confirming its effectiveness.