FantasyID: Face Knowledge Enhanced ID-Preserving Video Generation
Authors: name: Yunpeng Zhang, name: Qiang Wang, name: Fan Jiang, name: Yaqi Fan, name: Mu Xu, name: Yonggang Qi

Tuning-free approaches adapting large-scale pre-trained video diffusion
models for identity-preserving text-to-video generation (IPT2V) have gained
popularity recently due to their efficacy and scalability. However, significant
challenges remain to achieve satisfied facial dynamics while keeping the
identity unchanged. In this work, we present a novel tuning-free IPT2V
framework by enhancing face knowledge of the pre-trained video model built on
diffusion transformers (DiT), dubbed FantasyID. Essentially, 3D facial geometry
prior is incorporated to ensure plausible facial structures during video
synthesis. To prevent the model from learning copy-paste shortcuts that simply
replicate reference face across frames, a multi-view face augmentation strategy
is devised to capture diverse 2D facial appearance features, hence increasing
the dynamics over the facial expressions and head poses. Additionally, after
blending the 2D and 3D features as guidance, instead of naively employing
cross-attention to inject guidance cues into DiT layers, a learnable
layer-aware adaptive mechanism is employed to selectively inject the fused
features into each individual DiT layers, facilitating balanced modeling of
identity preservation and motion dynamics. Experimental results validate our
model's superiority over the current tuning-free IPT2V methods.