๐ค AI Summary
Traditional diffusion models rely on a large number of time steps to ensure asymptotic Gaussianity in the reverse process, resulting in inefficient training. This work challenges that assumption and proposes a T-space decoupled training paradigm: by optimizing the noise schedule, the diffusion process is fully decoupled into a single latent state, enabling independent and parallel training across all time steps. This eliminates sequential dependencies, facilitating distributed training and ensemble sampling. Experiments on ImageNet and CelebA demonstrate 4โ6ร faster convergence, with FID and LPIPS scores matching or surpassing those of baseline models, while significantly reducing computational overhead. The core contribution is the first realization of complete T-space decoupling into a single stateโestablishing a novel, highly efficient training paradigm for diffusion models.
๐ Abstract
We challenge a fundamental assumption of diffusion models, namely, that a large number of latent-states or time-steps is required for training so that the reverse generative process is close to a Gaussian. We first show that with careful selection of a noise schedule, diffusion models trained over a small number of latent states (i.e. $T sim 32$) match the performance of models trained over a much large number of latent states ($T sim 1,000$). Second, we push this limit (on the minimum number of latent states required) to a single latent-state, which we refer to as complete disentanglement in T-space. We show that high quality samples can be easily generated by the disentangled model obtained by combining several independently trained single latent-state models. We provide extensive experiments to show that the proposed disentangled model provides 4-6$ imes$ faster convergence measured across a variety of metrics on two different datasets.