arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2012.10102cs.CV
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真实世界超分辨率的频率一致自适应

Frequency Consistent Adaptation for Real World Super Resolution

National Key Lab for Novel Software Technology, Nanjing University(南京大学计算机软件新技术国家重点实验室);Tencent Youtu Lab(腾讯云图实验室)

Xiaozhong Ji, Guangpin Tao, Yun Cao, Ying Tai, Tong Lu, Chengjie Wang, Jilin Li, Feiyue Huang

摘要:

最近基于深度学习的超分辨率(SR)方法在已知退化的图像上取得了显着的性能。然而,这些方法在现实世界的场景中总是失败,因为理想退化后的低分辨率(LR)图像(例如,双三次下采样)偏离实源域。LR图像和真实世界图像之间的域间隙可以在频率密度上清楚地观察到,这启发我们显式地缩小由不正确的退化引起的不期望的间隙。从这个角度来看,我们设计了一种新的频率一致性自适应(FCA),确保频域的一致性时,将现有的SR方法应用到真实场景。我们从无监督图像中估计退化核,并生成相应的LR图像。为了给核估计提供有用的梯度信息,我们提出了频率密度比较器(FDC),通过区分图像在不同尺度上的频率密度。基于领域一致的LR-HR对,我们训练易于实现的卷积神经网络(CNN)SR模型。大量的实验表明,该FCA提高了真实世界环境下的SR模型的性能,实现了最先进的结果,具有高保真度和合理的感知,从而为真实世界的SR应用提供了一个新的有效框架。

英文摘要:

Recent deep-learning based Super-Resolution (SR) methods have achieved remarkable performance on images with known degradation. However, these methods always fail in real-world scene, since the Low-Resolution (LR) images after the ideal degradation (e.g., bicubic down-sampling) deviate from real source domain. The domain gap between the LR images and the real-world images can be observed clearly on frequency density, which inspires us to explictly narrow the undesired gap caused by incorrect degradation. From this point of view, we design a novel Frequency Consistent Adaptation (FCA) that ensures the frequency domain consistency when applying existing SR methods to the real scene. We estimate degradation kernels from unsupervised images and generate the corresponding LR images. To provide useful gradient information for kernel estimation, we propose Frequency Density Comparator (FDC) by distinguishing the frequency density of images on different scales. Based on the domain-consistent LR-HR pairs, we train easy-implemented Convolutional Neural Network (CNN) SR models. Extensive experiments show that the proposed FCA improves the performance of the SR model under real-world setting achieving state-of-the-art results with high fidelity and plausible perception, thus providing a novel effective framework for real-world SR application.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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