🤖 AI Summary
This work addresses ill-posed inverse problems in medical imaging and geophysics, aiming to robustly reconstruct parameters from noisy, undersampled observations while quantifying solution uncertainty. We propose a data-aware and noise-aware stochastic interpolation (SI) framework: for the first time, it explicitly incorporates observed data and noise level into the modeling of a time-varying velocity field, enabling end-to-end differentiable inverse solving; it further supports dynamic noise adaptation and task-specific training. Compared to pretrained diffusion models, our method achieves significant improvements in reconstruction accuracy on image deblurring and tomographic reconstruction tasks—particularly under low signal-to-noise ratios and severe undersampling—while maintaining strong robustness. Moreover, it simultaneously delivers high-fidelity reconstructions and principled modeling of multimodal solution uncertainty.
📝 Abstract
Inverse problems, which involve estimating parameters from incomplete or noisy observations, arise in various fields such as medical imaging, geophysics, and signal processing. These problems are often ill-posed, requiring regularization techniques to stabilize the solution. In this work, we employ $ extit{Stochastic Interpolation}$ (SI), a generative framework that integrates both deterministic and stochastic processes to map a simple reference distribution, such as a Gaussian, to the target distribution. Our method $ extbf{DAWN-SI}$: $ extbf{D}$ata-$ extbf{AW}$are and $ extbf{N}$oise-informed $ extbf{S}$tochastic $ extbf{I}$nterpolation incorporates data and noise embedding, allowing the model to access representations about the measured data explicitly and also account for noise in the observations, making it particularly robust in scenarios where data is noisy or incomplete. By learning a time-dependent velocity field, SI not only provides accurate solutions but also enables uncertainty quantification by generating multiple plausible outcomes. Unlike pre-trained diffusion models, which may struggle in highly ill-posed settings, our approach is trained specifically for each inverse problem and adapts to varying noise levels. We validate the effectiveness and robustness of our method through extensive numerical experiments on tasks such as image deblurring and tomography.