Papers › Flow-based Kernel Prior with Application to Blind Super-Resolution

Flow-based Kernel Prior with Application to Blind Super-Resolution

29 Mar 2021CVPR 2021 1arXiv:2103.15977archive 2025-07-28

Jingyun Liang, Kai Zhang, Shuhang Gu, Luc van Gool, Radu Timofte

Kernel estimation is generally one of the key problems for blind image super-resolution (SR). Recently, Double-DIP proposes to model the kernel via a network architecture prior, while KernelGAN employs the deep linear network and several regularization losses to constrain the kernel space. However, they fail to fully exploit the general SR kernel assumption that anisotropic Gaussian kernels are sufficient for image SR. To address this issue, this paper proposes a normalizing flow-based kernel prior (FKP) for kernel modeling. By learning an invertible mapping between the anisotropic Gaussian kernel distribution and a tractable latent distribution, FKP can be easily used to replace the kernel modeling modules of Double-DIP and KernelGAN. Specifically, FKP optimizes the kernel in the latent space rather than the network parameter space, which allows it to generate reasonable kernel initialization, traverse the learned kernel manifold and improve the optimization stability. Extensive experiments on synthetic and real-world images demonstrate that the proposed FKP can significantly improve the kernel estimation accuracy with less parameters, runtime and memory usage, leading to state-of-the-art blind SR results.

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BatchNorm JingyunLiang/FKP/FKP/network.py official repository ran fingerprinted Apache-2.0 (permissive) · eb02a51ee12f8816 · report
KernelPrior JingyunLiang/FKP/FKP/network.py official repository ran Apache-2.0 (permissive) · dd84d33d20283c71 · report

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Blind Super-ResolutionImage Super-ResolutionSuper-Resolution

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