What this tool does
Detects a single athlete in an ordinary video using on-device AI (BlazePose), builds a rotatable 3D skeleton estimate, and plots 3D joint angles over time. Everything runs in your browser; nothing is uploaded.
Important: this is an estimate
3D from a single camera is inferred depth, not measured. It is good for visualisation, gross movement assessment and relative joint angles, but it is not lab-grade 3D motion capture. Depth (toward/away from camera) is the weakest axis, and front/back or left/right confusion can occur, especially on rotations away from the camera.
Step by step
- Capture tab — load a video of one person, filmed roughly side-on or front-on.
- Set the FPS to match your clip, then click Process clip. The model downloads once (a few seconds) and then every frame is analysed — a progress bar shows where it is.
- Switch to the 3D Analysis tab. Drag to rotate the skeleton, scroll to zoom, and play or scrub the timeline.
- In the side panel, tick the joint angles you want to plot. Use Select all / Deselect all to manage the list.
- Export the angle time-series as CSV, or send it straight to the Figure builder.
Tips
- Best results: one person, well lit, filling a good portion of the frame, moving in the camera plane.
- Trim the clip before loading — every frame is processed, so shorter clips are faster.
- Gaps in an angle trace mean low confidence on one of its joints that frame; they are left blank rather than guessed.
Full reference →