FlashPortrait: 6x Faster Infinite Portrait Animation with Adaptive Latent Prediction
Current diffusion-based acceleration methods for long-portrait animation struggle to ensure identity (ID) consistency. This paper presents FlashPortrait, an end-to-end video diffusion transformer capable of synthesizing ID-preserving, infinite-length videos while achieving up to 6x acceleration in inference speed. In particular, FlashPortrait begins by computing the identity-agnostic facial expression features with an off-the-shelf extractor. It then introduces a Normalized Facial Expression Block to align facial features with diffusion latents by normalizing them with their respective means and variances, thereby improving identity stability in facial modeling. During inference, FlashPortrait adopts a dynamic sliding-window scheme with weighted blending in overlapping areas, ensuring smooth transitions and ID consistency in long animations. In each context window, based on the latent variation rate at particular timesteps and the derivative magnitude ratio among diffusion layers, FlashPortrait utilizes higher-order latent derivatives at the current timestep to directly predict latents at future timesteps, thereby skipping several denoising steps and achieving 6x speed acceleration. Experiments on benchmarks show the effectiveness of FlashPortrait both qualitatively and quantitatively.
6944c40afbf17e708e186067
Shuyuan Tu
claimed_verified
2025-12-19T16:25:50.475Z
66da6972eae491c64243e8f3
https://cdn-avatars.huggingface.co/v1/production/uploads/no-auth/SgX1j3QGKMk_YFTnM9Wr_.png
Shuyuan Tu
FrancisRing
user
FrancisRing
6944c40afbf17e708e186068
Yueming Pan
6944c40afbf17e708e186069
Yinming Huang
6944c40afbf17e708e18606a
Xintong Han
6944c40afbf17e708e18606b
Zhen Xing
6944c40afbf17e708e18606c
Qi Dai
6944c40afbf17e708e18606d
Kai Qiu
6944c40afbf17e708e18606e
Chong Luo
6944c40afbf17e708e18606f
Zuxuan Wu
FlashPortrait: 6x Faster Infinite Portrait Animation with Adaptive Latent Prediction
Current diffusion-based acceleration methods for long-portrait animation struggle to ensure identity (ID) consistency. This paper presents FlashPortrait, an end-to-end video diffusion transformer capable of synthesizing ID-preserving, infinite-length videos while achieving up to 6x acceleration in inference speed. In particular, FlashPortrait begins by computing the identity-agnostic facial expression features with an off-the-shelf extractor. It then introduces a Normalized Facial Expression Block to align facial features with diffusion latents by normalizing them with their respective means and variances, thereby improving identity stability in facial modeling. During inference, FlashPortrait adopts a dynamic sliding-window scheme with weighted blending in overlapping areas, ensuring smooth transitions and ID consistency in long animations. In each context window, based on the latent variation rate at particular timesteps and the derivative magnitude ratio among diffusion layers, FlashPortrait utilizes higher-order latent derivatives at the current timestep to directly predict latents at future timesteps, thereby skipping several denoising steps and achieving 6x speed acceleration. Experiments on benchmarks show the effectiveness of FlashPortrait both qualitatively and quantitatively.
FlashPortrait is a diffusion-based video transformer for long-portrait animation that ensures ID consistency and achieves 6x acceleration through a dynamic sliding-window scheme and higher-order latent derivatives.
video diffusion transformer ID-preserving infinite-length videos identity-agnostic facial expression features Normalized Facial Expression Block diffusion latents dynamic sliding-window scheme weighted blending latent variation rate derivative magnitude ratio higher-order latent derivatives