Recently, deep convolutional neural networks (CNNs) have been widely explored in single image super-resolution (SISR) and contribute remarkable progress. However, most of the existing CNNs-based SISR methods do not adequately explore contextual information in the feature extraction stage and pay little attention to the final high-resolution (HR) image reconstruction step, hence hindering the desired SR performance. To address the above two issues, in this paper, we propose a two-stage attentive network (TSAN) for accurate SISR in a coarse-to-fine manner. Specifically, we design a novel multi-context attentive block (MCAB) to make the network focus on more informative contextual features. Moreover, we present an essential refined attention block (RAB) which could explore useful cues in HR space for reconstructing fine-detailed HR image. Extensive evaluations on four benchmark datasets demonstrate the efficacy of our proposed TSAN in terms of quantitative metrics and visual effects. Code is available at https://github.com/Jee-King/TSAN.

本文提出了一种基于注意力机制的两阶段深度卷积神经网络，可以在从粗到细的方式下进行超分辨率图像重建，并通过使用多层上下文关联特征的多层上下文注意力块和利用高分辨率空间中的有用线索来重建高分辨率图像的重要细化关注块，以提高超分辨率性能并获得良好的视觉效果

一种两阶段注意力网络的单幅图像超分辨率方法