journal article·2026-05-07Open access

MAPGR: Multi-Agent Prompt-Guided Residual Diffusion for ancient mural restoration

Na Ren, Kun Huang

npj Heritage Science· Volume 14· Issue 1

Abstract

Digital inpainting provides a non-destructive approach to ancient mural conservation, but reconstructed content must remain grounded in verifiable historical evidence under the minimum intervention principle. Existing diffusion-based restoration models often rely on unconstrained generative priors, which can introduce implausible content in severely degraded regions. We propose Multi-Agent Prompt Guided Restoration (MAPGR), an evidence-driven framework that reformulates mural restoration as a multi-stage reasoning process. MAPGR constrains generation with diagnostic evidence and incorporates a dual-constraint diffusion architecture with a Semantic Modulation Block (SMB) and Mask-Guided Self-Attention (MG-SA) for stylistic and spatial control. Experiments on the DUNHUANG and DhMurals datasets demonstrate that MAPGR achieves strong restoration performance while improving interpretability and historical plausibility, offering an evidence-driven computational framework for ancient mural conservation.
Source: openalex_inverted_index · Quality: baseline

Research context

OpenAlex topics: Building materials and conservation · Image Processing and 3D Reconstruction · Cultural Heritage Materials Analysis

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

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