DocPure: Prompt-Free Unified Document Restoration via Degradation-Aware Structure-Guided Wavelet Modulation
This work addresses the degradation of document image quality caused by blur, noise, compression artifacts, and shadows during acquisition and transmission by proposing the first unified restoration framework that operates without task-specific prompts. The method employs a degradation-aware structural autoencoder to predict a clean structural prior and introduces a structure-guided wavelet interaction mechanism that bridges frequency-domain representations and spatial semantics for high-fidelity recovery. Key innovations include degradation-aware routing regularization and a cross-band adaptive modulation strategy, which effectively integrate low-frequency structural cues to guide high-frequency detail reconstruction. Extensive experiments demonstrate that the proposed approach consistently outperforms state-of-the-art methods across diverse degradation scenarios, exhibiting superior generalization capability and restoration performance.