Mural inpainting for structural distortion and color deviation: edge-constrained diffusion and adversarial optimization strategy

Murals are an essential component of cultural heritage; however, their digital restoration has long been constrained by severe structural fragmentation and chromatic degradation caused by material aging, environmental erosion, and historical damage. To address these challenges, this paper proposes a heritage-oriented digital mural restoration framework. The method first introduces an attention-guided edge prediction module to provide strong spatial supervision for subsequent generation. Then, under structural priors, a diffusion-based image inpainting framework is constructed and combined with a non-local color optimization module to ensure overall layout consistency, line continuity, and global color consistency. Experimental results on multiple mural datasets demonstrate that the proposed method significantly outperforms state-of-the-art approaches in terms of structural continuity and color consistency. Overall, the framework provides a controllable and interpretable technical pathway for noninvasive digital mural restoration, effectively supporting the digital documentation, scientific analysis, and long-term preservation of mural heritage.