What every part of biomex.studio does, in plain language. Looking for step-by-step instructions? Open Tutorials instead. By Andrew Callaway, Bournemouth University.
Tools
The toolbar on the right provides annotation tools. Select one and click on the video to place points.
Marker (M)
Places a tracking point on a feature — a joint, a ball, a landmark. Right-click (or long-press on mobile) to auto-track across frames using template matching. Adjust tracking settings in the Calibration tab.
Distance (L)
Click two points to measure the distance. Displays in pixels until you calibrate a scale.
Angle (A)
Click three points — ray, vertex, ray — to measure the angle at the vertex. For joint angles: proximal → target → distal (e.g. hip → knee → ankle).
Scale (C)
Draw a line over a known distance. A dialog asks for the real-world length. All measurements then display in real units.
Rectangle (R)
Click and drag to draw a rectangle. Useful for marking regions of interest or zones.
Freehand (D)
Click and drag to draw a freehand shape. Useful for tracing paths or highlighting areas.
Select (V)
Click to select annotations. Click and drag to reposition any point.
Video Controls
- Play / Pause — Space bar or ▶ button
- Frame step — ← → arrows (Shift for ±10)
- Speed — 0.1× to 2× via the dropdown
- Copy → Next — Duplicates all annotation positions to the next frame, then advances. Essential for manual frame-by-frame tracking.
- Screenshot — Saves the current frame (with annotations) as a PNG image.
Kinematics
Once an annotation has positions on 2+ frames, click 📈 on its card to open the kinematics chart panel.
Metrics
- Position — X/Y (markers), distance (lines), angle° (angles)
- Velocity — First derivative via central differences
- Acceleration — Second derivative
All kinematics respect the calibration scale and framerate. Export as CSV for analysis in Excel, MATLAB, or Python.
Export & Sessions
- CSV — Kinematics data for all tracked annotations
- Session JSON — Full backup: annotations, tracking data, calibration, metadata. Restore with Load Session.
Session files store everything except the video itself. Keep your session JSON and video file together for easy resumption.
Keyboard Shortcuts
Space — Play / Pause
← → — Step ±1 frame
Shift + ← → — Step ±10 frames
V Select · M Marker · L Distance · A Angle · C Scale
R Rectangle · D Freehand · F Copy → Next
Esc — Cancel tool / stop tracking
Shortcuts are disabled when typing in input fields.
Support
biomex.studio is free and always will be — no paywalls, no feature restrictions, no accounts required. If it helps your research, coaching, or teaching, a small donation helps cover development.
Found a bug? Use Report Issue in the top bar.