{"ID":2833137,"CreatedAt":"2026-06-01T04:54:23.091178241Z","UpdatedAt":"2026-06-01T04:54:23.091178241Z","DeletedAt":null,"paper_url":"https://arxiv.org/abs/2512.05076","arxiv_id":"2512.05076","title":"BulletTime: Decoupled Control of Time and Camera Pose for Video Generation","abstract":"Emerging video diffusion models achieve high visual fidelity but fundamentally couple scene dynamics with camera motion, limiting their ability to provide precise spatial and temporal control. We introduce a 4D-controllable video diffusion framework that explicitly decouples scene dynamics from camera pose, enabling fine-grained manipulation of both scene dynamics and camera viewpoint. Our framework takes continuous world-time sequences and camera trajectories as conditioning inputs, injecting them into the video diffusion model through a 4D positional encoding in the attention layer and adaptive normalizations for feature modulation. To train this model, we curate a unique dataset in which temporal and camera variations are independently parameterized; this dataset will be made public. Experiments show that our model achieves robust real-world 4D control across diverse timing patterns and camera trajectories, while preserving high generation quality and outperforming prior work in controllability. See our website for video results: https://19reborn.github.io/Bullet4D/","short_abstract":"Emerging video diffusion models achieve high visual fidelity but fundamentally couple scene dynamics with camera motion, limiting their ability to provide precise spatial and temporal control. We introduce a 4D-controllable video diffusion framework that explicitly decouples scene dynamics from camera pose, enabling fi...","url_abs":"https://arxiv.org/abs/2512.05076","url_pdf":"https://arxiv.org/pdf/2512.05076v1","authors":"[\"Yiming Wang\",\"Qihang Zhang\",\"Shengqu Cai\",\"Tong Wu\",\"Jan Ackermann\",\"Zhengfei Kuang\",\"Yang Zheng\",\"Frano Rajič\",\"Siyu Tang\",\"Gordon Wetzstein\"]","published":"2025-12-04T18:40:52Z","proceeding":"cs.CV","tasks":"[\"cs.CV\"]","methods":"[\"Diffusion Model\"]","has_code":false}