PGMv2: Structural-spatial-frequency contrastive reduction for mural high-fidelity restoration
摘要
Natural aging and human activities have eroded the Dunhuang murals’ structural integrity and color fidelity; restoration aims to reconstruct their original appearance. Building on a prior GAN-based progressive restoration framework, this paper introduces a synergistic mechanism integrating structural features with spatial-frequency domains to resolve color misalignment caused by decoupling color from structure in traditional methods. This method also serves as a digital guide for manual restoration. The framework includes a structural feature-based color generation module with three components: spatial-frequency dimensionality reduction, an attention-based U-Net backbone, and cross-scale, multi-dimensional feature fusion. A dataset of 6800 mural images and matched line art is released. Experiments show improvements over state-of-the-art methods (1.99%, 16.18%, 42.04% in SSIM, PSNR, LPIPS) and over the baseline (1.38%, 6.51%, 10.98%), confirming efficacy.