MSF: Efficient Diffusion Model Via Multi-Scale Latent Factorize
Journal:
arXiv
Published Date:
Jan 23, 2025
Abstract
Diffusion-based generative models have achieved remarkable progress in visual
content generation. However, traditional diffusion models directly denoise the
entire image from noisy inputs, disregarding the hierarchical structure present
in visual signals. This method is computationally intensive, especially for
high-resolution image generation. Signal processing often leverages
hierarchical decompositions; for instance, Fourier analysis decomposes signals
by frequency, while wavelet analysis captures localized frequency components,
reflecting both spatial and frequency information simultaneously. Inspired by
these principles, we propose a multiscale diffusion framework that generates
hierarchical visual representations, which are subsequently integrated to form
the final output. The diffusion model target, whether raw RGB pixels or latent
features from a Variational Autoencoder, s divided into multiple components
that each capture distinct spatial levels. The low-resolution component
contains the primary informative signal, while higher-resolution components add
high-frequency details, such as texture. This approach divides image generation
into two stages: producing a low-resolution base signal, followed by a
high-resolution residual signal. Both stages can be effectively modeled using
simpler, lightweight transformer architectures compared to full-resolution
generation. This decomposition is conceptually similar to wavelet decomposition
but offers a more streamlined and intuitive design. Our method, termed
MSF(short for Multi-Scale Factorization), achieves an FID of 2.2 and an IS of
255.4 on the ImageNet 256x256 benchmark, reducing computational costs by 50%
compared to baseline methods.