🤖 AI Summary
In low-light imaging, photon scarcity results in extremely low signal-to-noise ratios (SNR) in raw images, while existing deep denoising methods rely on large-scale paired clean-noisy datasets that are prohibitively difficult to acquire. To address this, we propose a novel data synthesis framework requiring only a single real noisy image and its corresponding dark frame. Our method first models signal-dependent noise via a Poisson distribution, then performs spectral sampling in the Fourier domain to generate realistic, signal-independent noise that preserves both authentic statistical properties and spatial structure. Unlike conventional approaches, it avoids oversimplified noise assumptions and eliminates the need for large-scale paired training data. Evaluated on multiple low-light denoising benchmarks, our method achieves state-of-the-art performance. It significantly reduces data acquisition cost while maintaining superior denoising fidelity.
📝 Abstract
Raw images taken in low-light conditions are very noisy due to low photon count and sensor noise. Learning-based denoisers have the potential to reconstruct high-quality images. For training, however, these denoisers require large paired datasets of clean and noisy images, which are difficult to collect. Noise synthesis is an alternative to large-scale data acquisition: given a clean image, we can synthesize a realistic noisy counterpart. In this work, we propose a general and practical noise synthesis method that requires only one single noisy image and one single dark frame per ISO setting. We represent signal-dependent noise with a Poisson distribution and introduce a Fourier-domain spectral sampling algorithm to accurately model signal-independent noise. The latter generates diverse noise realizations that maintain the spatial and statistical properties of real sensor noise. As opposed to competing approaches, our method neither relies on simplified parametric models nor on large sets of clean-noisy image pairs. Our synthesis method is not only accurate and practical, it also leads to state-of-the-art performances on multiple low-light denoising benchmarks.