Since the number of incident energies is limited, it is difficult to directly acquire hyperspectral images (HSI) with high spatial resolution. Considering the high dimensionality and correlation of HSI, super-resolution (SR) of HSI remains a challenge in the absence of auxiliary high-resolution images. Furthermore, it is very important to extract the spatial features effectively and make full use of the spectral information. This paper proposes a novel HSI super-resolution algorithm, termed dual-domain network based on hybrid convolution (SRDNet). Specifically, a dual-domain network is designed to fully exploit the spatial-spectral and frequency information among the hyper-spectral data. To capture inter-spectral self-similarity, a self-attention learning mechanism (HSL) is devised in the spatial domain. Meanwhile the pyramid structure is applied to increase the acceptance field of attention, which further reinforces the feature representation ability of the network. Moreover, to further improve the perceptual quality of HSI, a frequency loss(HFL) is introduced to optimize the model in the frequency domain. The dynamic weighting mechanism drives the network to gradually refine the generated frequency and excessive smoothing caused by spatial loss. Finally, In order to better fully obtain the mapping relationship between high-resolution space and low-resolution space, a hybrid module of 2D and 3D units with progressive upsampling strategy is utilized in our method. Experiments on a widely used benchmark dataset illustrate that the proposed SRDNet method enhances the texture information of HSI and is superior to state-of-the-art methods.
翻译:由于入射能量数量有限,直接获得高空间分辨率的高光谱图像(HSI)很困难。考虑到HSI的高维度和相关性,缺少辅助高分辨率图像时,HSI的超分辨率(SR)仍然是一个挑战。此外,有效地提取空间特征并充分利用光谱信息非常重要。本文提出了一种新颖的HSI超分辨率算法,名为基于混合卷积的双域网络(SRDNet)。具体而言,设计了双域网络来充分利用超光谱数据之间的空间光谱和频率信息。为了捕捉光谱之间的自相似性,设计了自注意学习机制(HSL)在空间域中。同时,金字塔结构被应用于增加注意力的接受场,进一步增强网络的特征表示能力。此外,为了进一步提高HSI的感知质量,引入了频率损失(HFL)来在频域优化模型。动态加权机制带动网络逐步改进了由空间损失引起的过度平滑的产生的频率。最后,为了更好地充分获得高分辨率空间和低分辨率空间之间的映射关系,在我们的方法中采用了2D和3D单元的混合模块,伴随递进的上采样策略。在广泛使用的基准数据集上的实验说明,所提出的SRDNet方法提高了HSI的纹理信息,并且优于现有最先进的方法。