Metadata track
Also known as: data track, timed metadata
A stream inside a video file carrying neither picture nor sound but time-stamped information about them, sample by sample.
Updated
What it means
A container holds several streams. Video, audio and, alongside them, tracks of data stamped so each sample lines up with a moment in the recording rather than with the file taken as a whole.
That is what separates it from file-level tags. Video metadata describes the whole clip; a metadata track describes each instant of it, which is a different kind of information entirely.
Action cameras use it heavily. GPMF telemetry on a GoPro is exactly this: speed, position, orientation and accelerometer readings, all written continuously the whole time the camera is recording and all discarded by most tools.
How it works in practice
It survives in MP4 and MOV and almost nowhere else. Converting a clip to another container is the usual way the track quietly disappears, and nothing in the process warns that it has gone.
Telemetry is what makes overlays possible. A Telemetry overlay showing speed or altitude reads this track, so a clip that lost the track cannot have an overlay added to it afterwards at all.
Stabilisation can use it too. Gyroscope samples written as a track are what let Gyroflow correct a clip far better than analysing analysing the picture alone could ever manage.
What to watch out for
Most tools discard it silently. A Transcoding step, a trim in a basic editor or an upload to a platform all tend to drop the track without any indication at all that it happened.
Nothing in the picture reveals whether it is there. Two identical-looking clips can differ entirely in what they carry, and only an inspection tool answers the question either way.
Privacy sits in it. Position samples describe exactly where somebody was at each moment of a ride, which is worth knowing about before a raw clip gets shared anywhere public.
How RawClip handles it
Where telemetry is present it is read and used, since speed and orientation help separate a travelling shot from a stationary one. A clip that lost its data track during an export is analysed on the picture alone, which works and reveals less.