Toonify3D: StyleGAN-based 3D Stylized Face Generator

Recent advances in generative models enable high-quality facial image stylization. Toonify is a popular StyleGAN-based framework that has been widely used for facial image stylization. Our goal is to create expressive 3D faces by turning Toonify into a 3D stylized face generator. Toonify is fine-tuned with a few gradient descent steps from StyleGAN trained for standard faces, and its features would carry semantic and visual information aligned with the features of the original StyleGAN model. Based on this observation, we design a versatile 3D-lifting method for StyleGAN, StyleNormal, that regresses a surface normal map of a StyleGAN-generated face using StyleGAN features. Due to the feature alignment between Toonify and StyleGAN, although StyleNormal is trained for regular faces, it can be applied for various stylized faces without additional fine-tuning. To learn local geometry of faces under various illuminations, we introduce a novel regularization term, the normal consistency loss, based on lighting manipulation in the GAN latent space. Finally, we present Toonify3D, a fully automated framework based on StyleNormal, that can generate full-head 3D stylized avatars and support GAN-based 3D facial expression editing.