Superresolution reconstruction method for ancient murals based on the stable enhanced generative adversarial network

Abstract

A stable enhanced superresolution generative adversarial network (SESRGAN) algorithm was proposed in this study to address the low-resolution and blurred texture details in ancient murals. This algorithm makes improvements on the basis of GANs, which use dense residual blocks to extract image features. After two upsampling steps, the feature information of the image is input into the high-resolution (HR) image space to realize an improvement in resolution, and the reconstructed HR image is finally generated. The discriminator network uses VGG as its basic framework to judge the authenticity of the input image. This study further optimized the details of the network model. In addition, three loss optimization models, i.e., the perceptual loss, content loss, and adversarial loss models, were integrated into the proposed algorithm. The Wasserstein GAN-gradient penalty (WGAN-GP) theory was used to optimize the adversarial loss of the model when calculating the perceptual loss and when using the preactivation feature information for calculation purposes. In addition, public data sets were used to pretrain the generative network model to achieve a high-quality initialization. The simulation experiment results showed that the proposed algorithm outperforms other related superresolution algorithms in terms of both objective and subjective evaluation indicators. A subjective perception evaluation was also conducted, and the reconstructed images produced by our algorithm were more in line with the general public’s visual perception than those produced by the other compared algorithms.