用连续时间优化提升图像翻译的细节还原能力。
Improving Image-to-Image Translation via a Rectified Flow Reformulation
- 通过噪声目标拼接输入,重构回归模型为连续运输过程。
- 仅需3步求解即可实现渐进式修复,显著提升清晰度与细节。
- 无需额外训练或蒸馏,适配主流图像翻译任务。
本文提出图像到图像修正流重构(I2I-RFR),一种可即插即用的 reformulation 方法,将标准像素级回归网络转化为连续时间传输模型。尽管像素级回归简单稳定,但常过度平滑病态或多重模式目标;生成式方法则需额外组件、特定调参和复杂训练推理流程。本方法通过通道拼接输入与噪声目标,并优化一个t-加权像素损失,该目标在诱导速度场下具有修正流解释,支持基于ODE的推理阶段渐进细化,同时基本保持原有监督训练流程。多数情况下,仅需扩展输入通道数,推理只需少数显式求解步骤(如3步)即可完成,无需蒸馏。在多个图像翻译与视频恢复任务中,I2I-RFR普遍提升性能,尤其在感知质量与细节保留上表现突出。整体上,I2I-RFR以轻量方式为传统I2I模型引入连续时间优化,无需重型生成管道。
原文摘要 · Abstract (English)
In this work, we propose Image-to-Image Rectified Flow Reformulation (I2I-RFR), a practical plug-in reformulation that recasts standard I2I regression networks as continuous-time transport models. While pixel-wise I2I regression is simple, stable, and easy to adapt across tasks, it often over-smooths ill-posed and multimodal targets, whereas generative alternatives often require additional components, task-specific tuning, and more complex training and inference pipelines. Our method augments the backbone input by channel-wise concatenation with a noise-corrupted version of the ground-truth target and optimizes a simple t-reweighted pixel loss. This objective admits a rectified-flow interpretation via an induced velocity field, enabling ODE-based progressive refinement at inference time while largely preserving the standard supervised training pipeline. In most cases, adopting I2I-RFR requires only expanding the input channels, and inference can be performed with a few explicit solver steps (e.g., 3 steps) without distillation. Extensive experiments across multiple image-to-image translation and video restoration tasks show that I2I-RFR generally improves performance across a wide range of tasks and backbones, with particularly clear gains in perceptual quality and detail preservation. Overall, I2I-RFR provides a lightweight way to incorporate continuous-time refinement into conventional I2I models without requiring a heavy generative pipeline.
Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。