Abstract：Artifacts on sharp edges are easily generated when the dilated convolutional neural network(CNN) is utilized in the existing image denoising methods based on deep learning. Moreover, multiple specific denoising models are required to be trained to deal with different noise levels. Aiming at these problems, a Gaussian denoising method with tunable noise level based on dilated CNN is proposed. A noise level map is employed to make the noise level tunable. Besides, the improved dilated CNN and the reversible downsampling technology are employed, and thus the problem of artifacts on sharp edges caused by traditional dilated CNN is alleviated. The downsampled sub-images and corresponding noise level map are input into the nonlinear mapping model. Then, the model is trained by the improved CNN with the dilated rate reduced. Experiments show that the proposed method gains GPU acceleration and the ability of adjusting the noise level with the artifacts on sharp edges improved and more image details retained.
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