ACT-Diffusion: Efficient Adversarial Consistency Training for One-step Diffusion Models
Authors: Fei Kong, Jinhao Duan, Lichao Sun, Hao Cheng, Renjing Xu, Hengtao Shen, Xiaofeng Zhu, Xiaoshuang Shi, Kaidi Xu

Though diffusion models excel in image generation their step-by-step denoising leads to slow generation speeds. Consistency training addresses this issue with single-step sampling but often produces lower-quality generations and requires high training costs. In this paper we show that optimizing consistency training loss minimizes the Wasserstein distance between target and generated distributions. As timestep increases the upper bound accumulates previous consistency training losses. Therefore larger batch sizes are needed to reduce both current and accumulated losses. We propose Adversarial Consistency Training (ACT) which directly minimizes the Jensen-Shannon (JS) divergence between distributions at each timestep using a discriminator. Theoretically ACT enhances generation quality and convergence. By incorporating a discriminator into the consistency training framework our method achieves improved FID scores on CIFAR10 and ImageNet 64x64 and LSUN Cat 256x256 datasets retains zero-shot image inpainting capabilities and uses less than 1/6 of the original batch size and fewer than 1/2 of the model parameters and training steps compared to the baseline method this leads to a substantial reduction in resource consumption. Our code is available: https://github.com/kong13661/ACT