mocap

Motion capture, or mocap, is the process of recording movement of objects or people for use in computer animation, visual effects, virtual reality, and biomechanics. The captured data describe the position, orientation, and timing of joints and limbs, enabling digital characters to mirror real performances or to analyze movement.

Mocap methods vary. Marker-based optical systems use infrared cameras and reflective markers placed on the subject; the cameras detect the markers and compute 3D joint positions. Markerless optical mocap relies on computer vision to estimate pose without markers. Inertial mocap employs wearable sensors (IMUs) that track acceleration and rotation. Hybrid approaches combine these technologies to improve accuracy and robustness, while real-time mocap streams data directly into production pipelines or game engines.

Typical workflow involves performers wearing suits or markers, or using markerless setups. The capture data are cleaned, labeled, and retargeted to a digital skeleton that matches the character’s proportions. Animators may refine timing, spacing, and facial expression. Advances have enabled real-time mocap, allowing immediate feedback in virtual production and interactive applications.

Applications span film and television VFX, video games, animation, broadcast, virtual production, and research in biomechanics and sports science. Common data formats include BVH and C3D, which are then imported into 3D software and game engines for retargeting and integration. Limitations include marker occlusion, calibration requirements, cost, and, for markerless systems, accuracy under variable conditions. The field continues to pursue higher precision, more wearable systems, and real-time, accessible mocap workflows.