titleCross-scale Aligned Supervision for Training GANs
authorsSangeek Hyun, MinKyu Lee, Jae-Pil Heo
date2026-05-26
venuearXiv (preprint, not peer reviewed)
idarXiv:2605.26449
upvotes1 (Hugging Face Daily Papers, 2026-11-01)
linksabs pdf hf
abstractModern GANs often introduce adversarial supervision on intermediate generator outputs and interpret the resulting multi-stage synthesis as coarse-to-fine hierarchical generation. In this work, we challenge this interpretation. We argue that standard scale-wise adversarial supervision does not construct a proper coarse-to-fine hierarchy: each intermediate image is independently pushed toward the real distribution at its own resolution, but this scale-wise realism does not ensure that outputs across stages represent the identical generated sample. Moreover, the scale-specific image produced at each stage is not used as an explicit refinement target for the subsequent stage. Therefore, its adversarial loss can improve a scale-specific output without constraining later stages to preserve the same sample trajectory, allowing them to move toward a different sample rather than refine the previous output. We refer to this problem as a cross-scale trajectory misalignment problem. To resolve it, we propose CAT, a Cross-scale Aligned Transformer for multi-scale adversarial generation. CAT keeps the discriminator scale-wise, so each intermediate output is evaluated at its own resolution, while adding a simple generator-side consistency regularization that aligns intermediate outputs with the final output. On class-conditional ImageNet-256, CAT-H/2 achieves an FID-50K of 1.56 with one-step inference after only 60 training epochs, outperforming strong one-step GAN and diffusion/flow baselines.

cite

@misc{hyun2026cross,
  title={Cross-scale Aligned Supervision for Training GANs},
  author={Sangeek Hyun and MinKyu Lee and Jae-Pil Heo},
  year={2026},
  eprint={2605.26449},
  archivePrefix={arXiv},
  url={https://arxiv.org/abs/2605.26449}
}