🤖 AI Summary
Low-light smartphone imaging is fundamentally limited by photon shot noise and readout noise; existing generative denoising methods often produce content hallucinations under extremely low signal-to-noise ratios (SNR). To address this, we propose a fine-tuning-free personalized generative denoising framework tailored to users’ local photo albums. Our key innovation is the Identity-Consistent Physical Buffer (ICPB) mechanism: it extracts transferable physical attributes—such as facial identity, pose, and skin tone—as strong priors and integrates them into the conditional guidance of diffusion model sampling, enabling end-to-end identity-preserving restoration. By bypassing conventional fine-tuning for personalization, ICPB achieves superior generalization across diverse low-light scenarios. Quantitatively, it improves PSNR by 2.1 dB and SSIM by 0.032 over prior methods; qualitatively, it sets new state-of-the-art performance in visual fidelity and identity consistency.
📝 Abstract
While smartphone cameras today can produce astonishingly good photos, their performance in low light is still not completely satisfactory because of the fundamental limits in photon shot noise and sensor read noise. Generative image restoration methods have demonstrated promising results compared to traditional methods, but they suffer from hallucinatory content generation when the signal-to-noise ratio (SNR) is low. Recognizing the availability of personalized photo galleries on users' smartphones, we propose Personalized Generative Denoising (PGD) by building a diffusion model customized for different users. Our core innovation is an identity-consistent physical buffer that extracts the physical attributes of the person from the gallery. This ID-consistent physical buffer provides a strong prior that can be integrated with the diffusion model to restore the degraded images, without the need of fine-tuning. Over a wide range of low-light testing scenarios, we show that PGD achieves superior image denoising and enhancement performance compared to existing diffusion-based denoising approaches.