This page covers writing the playout to a file. It can run alongside a stream or on its own, and because the picture is encoded once and used twice, recording next to a stream is nearly free.
The settings
Settings → Outputs, kind Stream / recording:
| Setting | What it is |
|---|---|
| Recording folder | Where the files go; the … button beside it picks one. An empty folder means REC does nothing. |
| Recording format | MKV (survives a crash), MP4, MOV or MPEG-TS. |
| Also save as MP4 afterwards | Copies the recording into an MP4 when it stops. Not offered when the format is already MP4. |
| Record while streaming | STREAM also starts and stops the recording; a recording you started yourself keeps running. Off by default. |
Why MKV
An MKV can be read up to the point where it stops, so a power cut or a crash mid-recording leaves you with everything recorded until that moment. An MP4 that was never closed properly will not open at all.
And why MP4 afterwards anyway
Because editing software, upload forms and the person who asked for a copy all want an MP4.
Also save as MP4 afterwards copies the finished recording into an MP4 without re-encoding, so it costs disk and a little time but no quality. The original MKV stays where it is.
Switch it on and you get the best of both: an MKV that survives, and an MP4 you can hand over.
Starting and stopping
REC on that playout’s transport bar. While Record while streaming is off, it is independent of the stream: you can record without streaming, stream without recording, or start the recording first and the stream later.
Recording is also independent of the cue list. It records what the playout puts out, whatever that happens to be, until you stop it.
Practical notes
Watch the disk. An hour at a normal bitrate is a few gigabytes; a morning of recordings adds up, and a full disk stops a recording mid-service.
Record locally, copy afterwards. A recording straight onto a network share depends on that share for its whole length. Local disk, then copy.
Check the folder before the show, not after. A folder that no longer exists, or that this user cannot write to, is the one failure you cannot fix afterwards.