UniMoCa: Unifying Motion and Camera Controls as Visual Proxies for Faithful Human Video Generation

2026-08-03Computer Vision and Pattern Recognition

Computer Vision and Pattern Recognition
AI summary

The authors address the challenge of controlling both human motion and camera movements in videos, especially when multiple people and complex actions are involved. They introduce a new method called UniMoCa that represents motion and camera data together as visual images, making it easier for video generation models to understand and use these controls. Their approach converts 3D human movements and camera paths into a shared visual format, improving how videos are generated with realistic motion and camera handling. They also created a dataset to test their method and showed it works better than previous approaches in maintaining consistent and controllable video outputs.

human motion controlcamera trajectoryvideo generation3D human posevisual proxymulti-person scenestemporal consistencymotion embeddingcamera embeddingmotion-camera representation
Authors
Liming Tan, Ye Chen, Hao Zhang, Lirong Qian, Feifei Li, Bingbing Ni
Abstract
Controlling human motion and camera movement is essential for faithful human-oriented video generation, yet remains challenging in multi-person scenes with large body motions, occlusions, and dynamic cameras. Existing pipelines typically rely on visual motion sequences, such as skeleton maps, pose maps, or rendered body representations, for motion control, while using camera embeddings for camera control. Such heterogeneous control interfaces force video generation models to reconcile pixel-aligned visual cues with non-visual geometric embeddings, making motion-camera attribution difficult and sensitive to camera estimation errors. We propose \textbf{UniMoCa}, a representation-driven framework that unifies motion and camera controls in visual space. At the core of UniMoCa is \textbf{Motion-Camera Visual Proxy} (\textbf{MCVP}), a mutually-sharable novel representation that converts 3D human motion and camera trajectories extracted from driving videos into an identity-neutral visual proxy. MCVP renders temporally aligned human geometry under the recovered camera trajectory and augments it with explicit camera trajectory markers, replacing heterogeneous visual-parametric controls with distinguishable visual cues. As both control factors are represented in the same visual space, they become mutually compatible rather than heterogeneous, enabling consistent joint reasoning and editing during video generation. We further curate a \textbf{MCVP-Video} dataset covering complex actions, multi-person interactions, and diverse camera trajectories. Experiments based on the Wan2.2 I2V show that UniMoCa achieves substantial gains in human motion control, camera control, temporal consistency, and camera-aware robustness with minimal additional complexity. More details are shown in our Project page: https://tanliming-daniel.github.io/UniMoCa/.