English
Related papers

Related papers: Diffusion Alignment as Variational Expectation-Max…

200 papers

Diffusion models excel in solving imaging inverse problems due to their ability to model complex image priors. However, their reliance on large, clean datasets for training limits their practical use where clean data is scarce. In this…

Computer Vision and Pattern Recognition · Computer Science 2024-07-02 Weimin Bai , Yifei Wang , Wenzheng Chen , He Sun

Few-step diffusion models enable efficient high-resolution image synthesis but struggle to align with specific downstream objectives due to limitations of existing reinforcement learning (RL) methods in low-step regimes with limited state…

Machine Learning · Computer Science 2026-03-02 Ziyi Zhang , Li Shen , Sen Zhang , Deheng Ye , Yong Luo , Miaojing Shi , Dongjing Shan , Bo Du , Dacheng Tao

Diffusion models have revolutionized generative tasks through high-fidelity outputs, yet flow matching (FM) offers faster inference and empirical performance gains. However, current foundation FM models are computationally prohibitive for…

Computer Vision and Pattern Recognition · Computer Science 2025-06-04 Johannes Schusterbauer , Ming Gui , Frank Fundel , Björn Ommer

Bridging the gap between diffusion models and human preferences is crucial for their integration into practical generative workflows. While optimizing downstream reward models has emerged as a promising alignment strategy, concerns arise…

Machine Learning · Computer Science 2026-03-02 Ziyi Zhang , Sen Zhang , Yibing Zhan , Yong Luo , Yonggang Wen , Dacheng Tao

Diffusion models have become the de-facto approach for generating visual data, which are trained to match the distribution of the training dataset. In addition, we also want to control generation to fulfill desired properties such as…

Machine Learning · Computer Science 2024-12-30 Dinghuai Zhang , Yizhe Zhang , Jiatao Gu , Ruixiang Zhang , Josh Susskind , Navdeep Jaitly , Shuangfei Zhai

In a convergence of machine learning and biology, we reveal that diffusion models are evolutionary algorithms. By considering evolution as a denoising process and reversed evolution as diffusion, we mathematically demonstrate that diffusion…

Neural and Evolutionary Computing · Computer Science 2026-05-12 Yanbo Zhang , Benedikt Hartl , Hananel Hazan , Michael Levin

Diffusion models excel at sampling from complex, unnormalized distributions. In this work, we extend Maximum Entropy Reinforcement Learning (ME-RL) to diffusion processes, enabling sampling from the optimal policy trajectory distribution.…

Machine Learning · Computer Science 2026-05-28 Sebastian Sanokowski , Kaustubh Patil

Reinforcement learning (RL) has emerged as a powerful tool for aligning diffusion models with human preferences, typically by optimizing a single reward function under a KL regularization constraint. In practice, however, human preferences…

Machine Learning · Computer Science 2026-04-17 Qi Zhang , Dawei Wang , Shaofeng Zou

Preference alignment in diffusion models has primarily focused on benign human preferences (e.g., aesthetic). In this paper, we propose a novel perspective: framing unrestricted adversarial example generation as a problem of aligning with…

Computer Vision and Pattern Recognition · Computer Science 2025-06-03 Kaixun Jiang , Zhaoyu Chen , Haijing Guo , Jinglun Li , Jiyuan Fu , Pinxue Guo , Hao Tang , Bo Li , Wenqiang Zhang

Diffusion models achieve state-of-the-art generative performance but are fundamentally bottlenecked by their slow, iterative sampling process. While diffusion distillation techniques enable high-fidelity, few-step generation, traditional…

Computer Vision and Pattern Recognition · Computer Science 2026-04-01 Linqian Fan , Peiqin Sun , Tiancheng Wen , Shun Lu , Chengru Song

Reinforcement learning (RL) has shown extraordinary potential in aligning diffusion models to downstream tasks, yet most of them still suffer from significant reward hacking, which degrades generative diversity and quality by inducing…

Machine Learning · Computer Science 2026-05-14 Jiaming Li , Chenyu Zhu , Nanxi Yi , Youjun Bao , Li Sun , Quanying Lv , Xiang Fang , Daizong Liu , Jianjun Li , Kun He , Bowen Zhou , Zhiyuan Ma

Adapting pretrained diffusion models to downstream objectives such as inverse problems often requires expensive test-time guidance or optimization. We propose a principled framework for generating high-quality reward-aligned samples at…

Machine Learning · Computer Science 2026-05-22 Kushagra Pandey , Farrin Marouf Sofian , Jan Niklas Groeneveld , Felix Draxler , Stephan Mandt

Prior work in multi-objective reinforcement learning typically uses linear reward scalarization with fixed weights, which provably fails to capture non-convex Pareto fronts and thus yields suboptimal results. This limitation becomes…

Machine Learning · Computer Science 2026-04-01 Yining Lu , Zilong Wang , Shiyang Li , Xin Liu , Changlong Yu , Qingyu Yin , Zhan Shi , Zixuan Zhang , Meng Jiang

We propose Diffusion-Sharpening, a fine-tuning approach that enhances downstream alignment by optimizing sampling trajectories. Existing RL-based fine-tuning methods focus on single training timesteps and neglect trajectory-level alignment,…

Computer Vision and Pattern Recognition · Computer Science 2025-02-18 Ye Tian , Ling Yang , Xinchen Zhang , Yunhai Tong , Mengdi Wang , Bin Cui

We present Distributional RewArds for Generative OptimizatioN (DRAGON), a versatile framework for fine-tuning media generation models towards a desired outcome. Compared with traditional reinforcement learning with human feedback (RLHF) or…

Sound · Computer Science 2025-11-18 Yatong Bai , Jonah Casebeer , Somayeh Sojoudi , Nicholas J. Bryan

Diffusion models have achieved remarkable success in text-to-image generation. However, their practical applications are hindered by the misalignment between generated images and corresponding text prompts. To tackle this issue,…

Computer Vision and Pattern Recognition · Computer Science 2025-03-28 Zijing Hu , Fengda Zhang , Long Chen , Kun Kuang , Jiahui Li , Kaifeng Gao , Jun Xiao , Xin Wang , Wenwu Zhu

The unsupervised task of aligning two or more distributions in a shared latent space has many applications including fair representations, batch effect mitigation, and unsupervised domain adaptation. Existing flow-based approaches estimate…

Machine Learning · Computer Science 2022-03-17 Zeyu Zhou , Ziyu Gong , Pradeep Ravikumar , David I. Inouye

Recent studies have demonstrated significant progress in aligning text-to-image diffusion models with human preference via Reinforcement Learning from Human Feedback. However, while existing methods achieve high scores on automated reward…

Computer Vision and Pattern Recognition · Computer Science 2026-03-11 Chubin Chen , Sujie Hu , Jiashu Zhu , Meiqi Wu , Jintao Chen , Yanxun Li , Nisha Huang , Chengyu Fang , Jiahong Wu , Xiangxiang Chu , Xiu Li

Model-based reinforcement learning methods often use learning only for the purpose of estimating an approximate dynamics model, offloading the rest of the decision-making work to classical trajectory optimizers. While conceptually simple,…

Machine Learning · Computer Science 2022-12-22 Michael Janner , Yilun Du , Joshua B. Tenenbaum , Sergey Levine

The Diffusion Probabilistic Model (DPM) has emerged as a highly effective generative model in the field of computer vision. Its intermediate latent vectors offer rich semantic information, making it an attractive option for various…

Computer Vision and Pattern Recognition · Computer Science 2023-03-29 Haipeng Zhou , Lei Zhu , Yuyin Zhou