FFmpeg OpenBSD

FFmpeg scripts for screen recording YouTube videos and YouTube live streaming on OpenBSD.

Stream Key

If you intend to do live streaming, make sure to place your Stream Key under the ~/Document/.streamkey file.

Enable microphone

The microphone is disabled by default on OpenBSD.

Temporary enable:

$ doas sysctl kern.audio.record=1

Permanently:

# echo kern.audio.record=1 >> /etc/sysctl.conf

Audio playback

The scripts are capable of recording/streaming audio playback as well. It is done by utilzing mon0. in sndio. You need to enable that or modify the scripts.

Enabling mon:

$ doas rcctl set sndiod flags -v 80 -s default -m play,mon -s mon && doas rcctl restart sndiod

You can specify the volume of playback with -v flag.

Microphone volume control

It is impossible to control microphone volume using FFmpeg. You need to set it with sndio or cmixer. I recommend the latter.

Install cmixer:

$ doas pkg_add cmixer

If you open the program, it defaults to snd/0, your internal sound card.

To switch the sound card, you must export the AUDIODEVICE variable and then open the mixer.

Example,

$ export AUDIODEVICE=snd/1 # pointing to the first external sound card
$ cmixer
$ unset AUDIODEVICE

Putting it all together, you can create an alias,

$ alias cmixer-microphone='export AUDIODEVICE=snd/1;cmixer;unset AUDIODEVICE'

Source

• OpenBSD FAQ 13 - Multimedia