SpectralAR: Spectral Autoregressive Visual Generation
Journal:
arXiv
Published Date:
Jun 12, 2025
Abstract
Autoregressive visual generation has garnered increasing attention due to its
scalability and compatibility with other modalities compared with diffusion
models. Most existing methods construct visual sequences as spatial patches for
autoregressive generation. However, image patches are inherently parallel,
contradicting the causal nature of autoregressive modeling. To address this, we
propose a Spectral AutoRegressive (SpectralAR) visual generation framework,
which realizes causality for visual sequences from the spectral perspective.
Specifically, we first transform an image into ordered spectral tokens with
Nested Spectral Tokenization, representing lower to higher frequency
components. We then perform autoregressive generation in a coarse-to-fine
manner with the sequences of spectral tokens. By considering different levels
of detail in images, our SpectralAR achieves both sequence causality and token
efficiency without bells and whistles. We conduct extensive experiments on
ImageNet-1K for image reconstruction and autoregressive generation, and
SpectralAR achieves 3.02 gFID with only 64 tokens and 310M parameters. Project
page: https://huang-yh.github.io/spectralar/.