MotionPrior: Exploring Efficient Learning of Motion Concepts for Few-Shot Video Generation

The diffusion-based text-to-image generation has achieved remarkable progress and realistic content generation performance, greatly promoting the development in text-to-video generation. Although equipped with powerful image diffusion models, video generation modeling still requires massive labeled data and a high training resource cost. Recent, work has been focused on cost-effective video generation in a one-shot or few-shot manner based on the image diffusion model with minimum demand for video data and computing resources. However, these video generation models only support the generation of one single motion pattern/concept. This raises an important question: Can we improve generation freedom with a light training burden? In this paper, we explore a cost-effective video generation scheme for adaptive motion concepts by learning motion priors from a small set of video data. Specifically, we construct a learnable bank for motion concepts and propose the Dual-Semantic-guided Motion Attention module to locate the corresponding motion elements from the bank with the guidance of textual semantic and visual semantic. The extracted motion elements are inserted into video latents via lightweight motion injection layer, which is capable of integrating motion semantic effectively with much fewer parameters compared to the conventional temporal attention layer. In addition, we introduce a temporal-aware noise prior and an inter-frame consistency constraint to strengthen the learning of temporal dependency and improve video smoothness. Extensive experiments validate that the proposed method can learn motion priors adaptively from a small set of training videos to generate smooth videos that involve either single or multiple motion concepts. The results demonstrate that the proposed scheme achieves superior performance compared to existing few-shot video generation methods and even some large-scale video generation models. More information and results are available at https://youncy-hu.github.io/motionprior/.