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. |
| Recording format | MKV, which survives a crash. |
| Also save as MP4 afterwards | Copies the recording into an MP4 when it stops. |
Why MKV
Because an MP4 that was never closed properly is worthless. An MP4 keeps the index it needs to be playable at the end of the file, so a power cut or a crash mid-recording leaves you with a file no player will open.
An MKV can be read up to the point where it stops. Whatever happens, you keep what was recorded until that moment.
And why MP4 afterwards anyway
Because everything else in the world wants an MP4: editing software, upload forms, the person who asked for a copy.
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. 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.