or click to browse — MP4 / WebM / MOV. Everything runs locally in your browser.
BRAKE
REC — HOLD SPACE WHEN ON THE BRAKES
Brake Map00:00.0 / 00:00.0
Telemetry
0
Brake Zones
0.0s
Time on Brakes
0%
% of Lap
ARM TO RECORDClick to arm, then press & hold to brake
How to record: hit ● Record Brakes, let the clip play, and hold Space
(or press & hold the pad above / your mouse) for as long as the brakes are applied. Release when you come off them.
Use slow-mo for precision. Each hold becomes a red zone. Play it back and the overlay lights up on the brakes.
runs video + sound (+ GPS if loaded), keeps only agreed zones
or use one method
best accuracy — uses real speed
– km/h
Decel threshold3.0
Min speed drop12
Sync offset0.0s
Play the video and watch the dot. Slide Sync offset until the dot reaches each corner exactly when the video does. Min speed drop rejects kerbs/bumps — raise it if kerbs still show as braking, since a kerb barely changes speed while real braking sheds km/h. Then detect.
GPS telemetry = exact braking. Your Action 5 stores GPS inside the MP4. Convert it to a track file
once with dji2racechrono
(outputs .nmea) — or any tool that gives .gpx/.csv — then import it here. Braking is
detected from real deceleration (m/s²), so corners, kerbs and traffic don't trigger it. Lower the
threshold to catch lighter braking; use sync offset if zones land slightly early/late vs the video.
or detect from video
ready
Sensitivity68
Optical-flow braking detection (no telemetry): plays the clip through once and measures the
divergence of the image's motion field (forward speed), ignoring head movement and cornering.
Braking = the field collapsing. Less exact than GPS — it can mistake corners/kerbs for braking —
so prefer the GPS import above when you have a track. Auto-zones are editable.
or detect from engine sound
tracks engine pitch (RPM)
threshold
Drop sensitivity60
Min duration0.4s
Engine-pitch detection: brakes are quiet, but braking means lifting the throttle, so the
engine note drops. The scan tracks the engine's harmonic signature (fundamental + overtones),
which separates it from wind (broadband, no harmonics) and voices (wrong band, weak harmonics),
and follows it continuously so a gust or shout can't yank it. The line is bright
where the engine is confidently locked and grey where it isn't — drops are only
counted in locked sections. Drop sensitivity sets how big a pitch fall counts. Brief dips that
rebound are ignored.
Brake Zones
No brake zones recorded yet.
Local-only · No upload to any server · Your footage never leaves this device