Graph-Structured Convolution-Guided Continuous Context Threshold-Aware Networks for Hyperspectral Image Classification
Weiwei Cai, Pengjiang Qian, Yao Ding, Meiqiao Bi, Xin Ning, Danfeng Hong, Xiao Bai
Abstract
Although convolutional neural networks (CNNs) have shown superior performance to traditional machine learning algorithms for hyperspectral image classification tasks, the ability of traditional CNNs to model remote dependencies in the spatial orientation of HSIs is still limited, and they always extract similar low-level features, leading to feature redundancy. To cope with this limitation, this paper proposes a novel multi-order statistical representation-guided graph convolution and continuous context threshold-aware network for the classification of hyperspectral images with limited training samples. Initially, the spectral spatial information is separately modeled using first-order features and second-order pooling operators. Secondly, we propose graph-structuring the patch’s features. By employing a random walk transition probability matrix, graph-structured convolution can mine more discriminative direction features. In addition, we design a continuous context threshold-aware network to model multidimensional spatial relationships, thereby enhancing the representation of graph features. Specifically, the cross-attention mechanism is used to calculate the attention weights in the vertical and horizontal directions, and the features are divided into two levels—important and secondary—by solving the cosine distance between feature vectors, and the former is retained and the latter is punished. Extensive experiments on multiple HSIs datasets demonstrated that the proposed method delivers competitive performance. The code will be available at: https://github.com/vivitsai/GSC-CCTA.