Training-Free Refinement of Flow Matching with Divergence-based Sampling
- URL: http://arxiv.org/abs/2604.04646v1
- Date: Mon, 06 Apr 2026 12:54:58 GMT
- Title: Training-Free Refinement of Flow Matching with Divergence-based Sampling
- Abstract summary: Flow Divergence Sampler (FDS) is a training-free framework that refines intermediate states before each solver step.<n>FDS exploits this signal to steer states toward less ambiguous regions.<n>As a plug-and-play framework compatible with standard solvers and off-the-shelf flow backbones, FDS consistently improves fidelity across various generation tasks.
- Score: 17.850801452423074
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Flow-based models learn a target distribution by modeling a marginal velocity field, defined as the average of sample-wise velocities connecting each sample from a simple prior to the target data. When sample-wise velocities conflict at the same intermediate state, however, this averaged velocity can misguide samples toward low-density regions, degrading generation quality. To address this issue, we propose the Flow Divergence Sampler (FDS), a training-free framework that refines intermediate states before each solver step. Our key finding reveals that the severity of this misguidance is quantified by the divergence of the marginal velocity field that is readily computable during inference with a well-optimized model. FDS exploits this signal to steer states toward less ambiguous regions. As a plug-and-play framework compatible with standard solvers and off-the-shelf flow backbones, FDS consistently improves fidelity across various generation tasks including text-to-image synthesis, and inverse problems.
Related papers
- Fast and Faithful: Principled Conditional Flow Matching for Inverse Problems [8.966524060251965]
Flow matching approaches to imaging inverse problems commonly incorporate measurements in two ways.<n>We propose a principled parametrization of the measurement-conditional velocity field to solve inverse problems.<n>Our method achieves state-of-the-art PSNR with $50times$ fewer evaluations function than the strongest flow baseline.
arXiv Detail & Related papers (2026-09-11T15:12:11Z) - Riemannian MeanFlow for One-Step Generation on Manifolds [54.09734511705173]
Flow Matching enables simulation-free training of generative models.<n>MeanFlow can be extended to manifold-valued generation where velocities lie in location-dependent tangent spaces.<n>Experiments on spheres, tori, and SO(3) demonstrate competitive one-step sampling with improved quality-efficiency trade-offs and substantially reduced sampling cost.
arXiv Detail & Related papers (2026-03-11T12:41:46Z) - FlowConsist: Make Your Flow Consistent with Real Trajectory [99.22869983378062]
We argue that current fast-flow training paradigms suffer from two fundamental issues.<n> conditional velocities constructed from randomly paired noise-data samples introduce systematic trajectory drift.<n>We propose FlowConsist, a training framework designed to enforce trajectory consistency in fast flows.
arXiv Detail & Related papers (2026-02-06T03:24:23Z) - Generative Modeling with Continuous Flows: Sample Complexity of Flow Matching [60.37045080890305]
We provide the first analysis of the sample complexity for flow-matching based generative models.<n>We decompose the velocity field estimation error into neural-network approximation error, statistical error due to the finite sample size, and optimization error due to the finite number of optimization steps for estimating the velocity field.
arXiv Detail & Related papers (2025-12-01T05:14:25Z) - A-FloPS: Accelerating Diffusion Sampling with Adaptive Flow Path Sampler [21.134678093577193]
A-FloPS is a principled, training-free framework for flow-based generative models.<n>We show that A-FloPS consistently outperforms state-of-the-art training-free samplers in both sample quality and efficiency.<n>With as few as $5$ function evaluations, A-FloPS achieves substantially lower FID and generates sharper, more coherent images.
arXiv Detail & Related papers (2025-08-22T13:28:16Z) - Rectified Flows for Fast Multiscale Fluid Flow Modeling [11.597597438962026]
We introduce a rectified flow framework that learns a time-dependent velocity field.<n>Our method makes each integration step much more effective, using as few as eight steps.<n> Experiments on challenging multiscale flow benchmarks show that rectified flows recover the same posterior distributions as diffusion models.
arXiv Detail & Related papers (2025-06-03T17:40:39Z) - PreAdaptFWI: Pretrained-Based Adaptive Residual Learning for Full-Waveform Inversion Without Dataset Dependency [8.719356558714246]
Full-waveform inversion (FWI) is a method that utilizes seismic data to invert the physical parameters of subsurface media.<n>Due to its ill-posed nature, FWI is susceptible to getting trapped in local minima.<n>Various research efforts have attempted to combine neural networks with FWI to stabilize the inversion process.
arXiv Detail & Related papers (2025-02-17T15:30:17Z) - Neural Flow Samplers with Shortcut Models [19.81513273510523]
Continuous flow-based neural samplers offer a promising approach to generate samples from unnormalized densities.<n>We introduce an improved estimator for these challenging quantities, employing a velocity-driven Sequential Monte Carlo method.<n>Our proposed Neural Flow Shortcut Sampler empirically outperforms existing flow-based neural samplers on both synthetic datasets and complex n-body system targets.
arXiv Detail & Related papers (2025-02-11T07:55:41Z) - Consistency Flow Matching: Defining Straight Flows with Velocity Consistency [97.28511135503176]
We introduce Consistency Flow Matching (Consistency-FM), a novel FM method that explicitly enforces self-consistency in the velocity field.
Preliminary experiments demonstrate that our Consistency-FM significantly improves training efficiency by converging 4.4x faster than consistency models.
arXiv Detail & Related papers (2024-07-02T16:15:37Z) - Diffusion Generative Flow Samplers: Improving learning signals through
partial trajectory optimization [87.21285093582446]
Diffusion Generative Flow Samplers (DGFS) is a sampling-based framework where the learning process can be tractably broken down into short partial trajectory segments.
Our method takes inspiration from the theory developed for generative flow networks (GFlowNets)
arXiv Detail & Related papers (2023-10-04T09:39:05Z) - The Score-Difference Flow for Implicit Generative Modeling [1.1929584800629673]
Implicit generative modeling aims to produce samples of synthetic data matching a target data distribution.<n>Recent work has approached the IGM problem from the perspective of pushing synthetic source data toward the target distribution.<n>We present the score difference between arbitrary target and source distributions as a flow that optimally reduces the Kullback-Leibler divergence between them.
arXiv Detail & Related papers (2023-04-25T15:21:12Z) - Reflected Diffusion Models [93.26107023470979]
We present Reflected Diffusion Models, which reverse a reflected differential equation evolving on the support of the data.
Our approach learns the score function through a generalized score matching loss and extends key components of standard diffusion models.
arXiv Detail & Related papers (2023-04-10T17:54:38Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.