Hyperspectral image super-resolution using cluster-based deep convolutional networks

Abstract

In recent years, deep convolutional neural networks (CNNs) have been widely exploited for the hyperspectral image (HSI) super-resolution and obtained remarkable performance. However, most of the existing CNN-based methods have two main problems. One is to use two-dimension (2D) convolution to extract spatial information without paying attention to the mining of spectral information of hyperspectral images. The other is to use three-dimension (3D) convolution, which reduces the efficiency of the model when the network parameters increase. To address the above issues, we propose clustering deep residual neural network (CDRNN) for hyperspectral image super-resolution in this paper. The proposed CDRNN learns the complex, nonlinear mappings between low spatial resolution HSI and high spatial resolution HSI. At first, an unsupervised clustering method is used to divide a low spatial resolution HSI into several classes according to spectral correlation. Then, the spectrum-pairs from the classified low spatial resolution HSI and the corresponding high spatial resolution HSI are used to train the CDRNN to establish the nonlinear mapping for each class. Finally, we classify the given low spatial resolution HSI into the determined category and use the trained CDRNN to reconstruct the final high spatial resolution HSI from the classified low spatial resolution HSI. We conduct extensive experiments on three simulated benchmark datasets and a real HSI to evaluate the super-resolution performance of the proposed method. Experimental results show that our proposed method achieves significant improvement over state-of-the-art methods.