“Alias-Free Generative Adversarial Networks”, Tero Karras, Miika Aittala, Samuli Laine, Erik Härkönen, Janne Hellsten, Jaakko Lehtinen, Timo Aila2021-06-23 (, ; similar)⁠:

[Github] We observe that despite their hierarchical convolutional nature, the synthesis process of typical generative adversarial networks depends on absolute pixel coordinates in an unhealthy manner. This manifests itself as, eg. detail appearing to be glued to image coordinates instead of the surfaces of depicted objects.

We trace the root cause to careless signal processing that causes aliasing in the generator network. Interpreting all signals in the network as continuous, we derive generally applicable, small architectural changes that guarantee that unwanted information cannot leak into the hierarchical synthesis process.

The resulting networks match the FID of StyleGAN2 but differ dramatically in their internal representations, and they are fully equivariant to translation and rotation even at subpixel scales. Our results pave the way for generative models better suited for video and animation.

G. Energy Consumption: The entire project consumed ~225 megawatt hours (MWh) of electricity. ~70% of it was used for exploratory runs, where we gradually built the new configurations; first in an unstructured manner and then specifically ironing out the new Alias-Free-T and Alias-Free-R configurations. Setting up the intermediate configurations between StyleGAN2 and our generators, as well as, the key parameter ablations was also quite expensive at ~15%. Training a single instance of Alias-Free-R at 1,024×1,024 is only slightly more expensive (0.9MWh) than training StyleGAN2 (0.7MWh)

Table 17: Computational effort expenditure and electricity consumption data for this project. The unit for computation is GPU-years on a single NVIDIA V100 GPU—it would have taken ~92 years to execute this project using a single GPU. See the text for additional details about the computation and energy consumption estimates. Early exploration includes early training runs that affected our decision to start this project. Project exploration includes training runs that were done specifically for this project, leading to the final Alias-Free-T and Alias-Free-R configurations. These runs were not intended to be used in the paper as-is. Setting up ablations includes hyperparameter tuning for the intermediate configurations and ablation experiments in Figure 3 & Figure 5. Per-dataset tuning includes hyperparameter tuning for individual datasets, mainly the grid search for R1 regularization weight. Config R at 1,024×1,024 corresponds to one training run in Figure 5, left, and Other runs in the dataset table includes the remaining runs. Ablation tables includes the low-resolution ablations in Figures 3 & Figure 5. Results intentionally left out includes additional results that were initially planned, but then left out to improve focus and clarity.