BVH / FBX Motion Capture File Formats

Two common motion-capture file formats that store a human skeleton's structure and its joint rotations frame by frame.

BVH (BioVision Hierarchy) was created by the motion-capture company Biovision and is a plain-text format: a HIERARCHY section describes the skeleton as a tree of ROOT and JOINT nodes, giving each joint's offset and rotation channels relative to its parent, while a MOTION section gives the frame count and frame time, followed by one line per frame listing each joint's rotation (the root joint also gets a translation). BVH stores only skeletal motion, not mesh or material data. FBX was originally designed by Kaydara for its Filmbox motion-capture software and is now owned by Autodesk; it can store geometry, skeleton, animation, and materials together, but the format itself isn't publicly documented, so it's normally read and written through Autodesk's official SDK. When humanoid robots imitate human motion, researchers commonly retarget human motion from these two file formats onto the robot's joints — for example, GMR supports both BVH from the LAFAN1 dataset and FBX exported from OptiTrack.

ExampleThe publicly released LAFAN1 motion-capture dataset from Ubisoft ships as BVH files; researchers use GMR to retarget walking and dancing clips from it onto the joints of the Unitree G1 humanoid, as reference motion for a motion-tracking policy.

Also called

BioVision Hierarchy, Filmbox, .bvh, .fbx

Related

Motion Capture · Motion Retargeting · General Motion Retargeting · LAFAN1 · AMASS (Archive of Motion Capture as Surface Shapes) · SMPL

Sources

Biovision BVH（威斯康星大学课程资料） (Chinese)
FBX - Wikipedia
GMR: General Motion Retargeting (GitHub)