Improving Consistency Models with Generator-Induced Flows
- URL: http://arxiv.org/abs/2406.09570v2
- Date: Mon, 14 Oct 2024 09:21:15 GMT
- Title: Improving Consistency Models with Generator-Induced Flows
- Authors: Thibaut Issenhuth, Sangchul Lee, Ludovic Dos Santos, Jean-Yves Franceschi, Chansoo Kim, Alain Rakotomamonjy,
- Abstract summary: Consistency models imitate the multi-step sampling of score-based diffusion in a single forward pass of a neural network.
They can be learned in two ways: consistency distillation and consistency training.
We propose a novel flow that transports noisy data towards their corresponding outputs derived from the currently trained model.
- Score: 16.049476783301724
- License:
- Abstract: Consistency models imitate the multi-step sampling of score-based diffusion in a single forward pass of a neural network. They can be learned in two ways: consistency distillation and consistency training. The former relies on the true velocity field of the corresponding differential equation, approximated by a pre-trained neural network. In contrast, the latter uses a single-sample Monte Carlo estimate of this velocity field. The related estimation error induces a discrepancy between consistency distillation and training that, we show, still holds in the continuous-time limit. To alleviate this issue, we propose a novel flow that transports noisy data towards their corresponding outputs derived from the currently trained model --~as a proxy of the true flow. Our empirical findings demonstrate that this approach mitigates the previously identified discrepancy. Furthermore, we present theoretical and empirical evidence indicating that our generator-induced flow surpasses dedicated optimal transport-based consistency models in effectively reducing the noise-data transport cost. Consequently, our method not only accelerates consistency training convergence but also enhances its overall performance. The code is available at: https://github.com/thibautissenhuth/consistency_GC.
Related papers
- Stable Consistency Tuning: Understanding and Improving Consistency Models [40.2712218203989]
Diffusion models achieve superior generation quality but suffer from slow generation speed due to iterative nature of denoising.
consistency models, a new generative family, achieve competitive performance with significantly faster sampling.
We propose a novel framework for understanding consistency models by modeling the denoising process of the diffusion model as a Markov Decision Process (MDP) and framing consistency model training as the value estimation through Temporal Difference(TD) Learning.
arXiv Detail & Related papers (2024-10-24T17:55:52Z) - Straightness of Rectified Flow: A Theoretical Insight into Wasserstein Convergence [54.580605276017096]
Rectified Flow (RF) aims to learn straight flow trajectories from noise to data using a sequence of convex optimization problems.
RF theoretically straightens the trajectory through successive rectifications, reducing the number of evaluations function (NFEs) while sampling.
We provide the first theoretical analysis of the Wasserstein distance between the sampling distribution of RF and the target distribution.
arXiv Detail & Related papers (2024-10-19T02:36:11Z) - Conditional Lagrangian Wasserstein Flow for Time Series Imputation [3.914746375834628]
We propose a novel method for time series imputation called Conditional Lagrangian Wasserstein Flow.
The proposed method leverages the (conditional) optimal transport theory to learn the probability flow in a simulation-free manner.
The experimental results on the real-word datasets show that the proposed method achieves competitive performance on time series imputation.
arXiv Detail & Related papers (2024-10-10T02:46:28Z) - 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) - Flow Map Matching [15.520853806024943]
Flow map matching is an algorithm that learns the two-time flow map of an underlying ordinary differential equation.
We show that flow map matching leads to high-quality samples with significantly reduced sampling cost compared to diffusion or interpolant methods.
arXiv Detail & Related papers (2024-06-11T17:41:26Z) - Towards Theoretical Understandings of Self-Consuming Generative Models [56.84592466204185]
This paper tackles the emerging challenge of training generative models within a self-consuming loop.
We construct a theoretical framework to rigorously evaluate how this training procedure impacts the data distributions learned by future models.
We present results for kernel density estimation, delivering nuanced insights such as the impact of mixed data training on error propagation.
arXiv Detail & Related papers (2024-02-19T02:08:09Z) - DiffuSeq-v2: Bridging Discrete and Continuous Text Spaces for
Accelerated Seq2Seq Diffusion Models [58.450152413700586]
We introduce a soft absorbing state that facilitates the diffusion model in learning to reconstruct discrete mutations based on the underlying Gaussian space.
We employ state-of-the-art ODE solvers within the continuous space to expedite the sampling process.
Our proposed method effectively accelerates the training convergence by 4x and generates samples of similar quality 800x faster.
arXiv Detail & Related papers (2023-10-09T15:29:10Z) - Observation-Guided Diffusion Probabilistic Models [41.749374023639156]
We propose a novel diffusion-based image generation method called the observation-guided diffusion probabilistic model (OGDM)
Our approach reestablishes the training objective by integrating the guidance of the observation process with the Markov chain.
We demonstrate the effectiveness of our training algorithm using diverse inference techniques on strong diffusion model baselines.
arXiv Detail & Related papers (2023-10-06T06:29:06Z) - Fast Sampling of Diffusion Models via Operator Learning [74.37531458470086]
We use neural operators, an efficient method to solve the probability flow differential equations, to accelerate the sampling process of diffusion models.
Compared to other fast sampling methods that have a sequential nature, we are the first to propose a parallel decoding method.
We show our method achieves state-of-the-art FID of 3.78 for CIFAR-10 and 7.83 for ImageNet-64 in the one-model-evaluation setting.
arXiv Detail & Related papers (2022-11-24T07:30:27Z) - How Much is Enough? A Study on Diffusion Times in Score-based Generative
Models [76.76860707897413]
Current best practice advocates for a large T to ensure that the forward dynamics brings the diffusion sufficiently close to a known and simple noise distribution.
We show how an auxiliary model can be used to bridge the gap between the ideal and the simulated forward dynamics, followed by a standard reverse diffusion process.
arXiv Detail & Related papers (2022-06-10T15:09:46Z)
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.