Knowledge Distillation for Image Restoration : Simultaneous Learning from Degraded and Clean Images
Yongheng Zhang, Danfeng Yan
TL;DR
The paper tackles the challenge of compressing image restoration models without sacrificing performance. It introduces Simultaneous Learning Knowledge Distillation (SLKD), a dual-teacher, single-student framework with Degradation Removal Learning (DRL) and Image Reconstruction Learning (IRL), guided by BRISQUE- and PIQE-based feature extractors and a Scale Conversion Module to learn from both degraded and clean inputs. Key contributions include a novel dual-teacher distillation scheme, feature-level losses L_NC and L_ET, and a joint image/pixel/ KL objective that yields substantial reductions in FLOPs and parameters (over 80%) while maintaining strong restoration performance across five datasets and three tasks (deraining, deblurring, denoising). Ablation studies validate the necessity of DRL, IRL, and the two feature-level losses. The approach enables efficient deployment of high-quality image restoration on resource-constrained platforms, offering a practical path for compact yet capable restoration models.
Abstract
Model compression through knowledge distillation has seen extensive application in classification and segmentation tasks. However, its potential in image-to-image translation, particularly in image restoration, remains underexplored. To address this gap, we propose a Simultaneous Learning Knowledge Distillation (SLKD) framework tailored for model compression in image restoration tasks. SLKD employs a dual-teacher, single-student architecture with two distinct learning strategies: Degradation Removal Learning (DRL) and Image Reconstruction Learning (IRL), simultaneously. In DRL, the student encoder learns from Teacher A to focus on removing degradation factors, guided by a novel BRISQUE extractor. In IRL, the student decoder learns from Teacher B to reconstruct clean images, with the assistance of a proposed PIQE extractor. These strategies enable the student to learn from degraded and clean images simultaneously, ensuring high-quality compression of image restoration models. Experimental results across five datasets and three tasks demonstrate that SLKD achieves substantial reductions in FLOPs and parameters, exceeding 80\%, while maintaining strong image restoration performance.
