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Revision as of 20:20, 29 August 2012 by Mrk3004 (Talk | contribs) (adding information about pulseaudio)

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GLC is an ALSA & OpenGL capture tool for Linux. It consists of a generic video capture, playback and processing library and a set of tools built around that library. GLC should be able to capture any application that uses ALSA for sound and OpenGL for drawing. It is similar to Fraps on Windows.


To install GLC, simply install the glc package from AUR.

If you want to record 32 bit programs such as Wine on a 64 bit system, you will also need to install lib32-glc.

NOTE: GLC will only work with ALSA. If you use Pulseaudio, install the glc-pulseaudio* packages instead. If you use OSS, you will probably need to record the audio separately.


The basic usage is simple. Just run this:

glc-capture [application]

Press Shift + F8 to start and stop recording. By default, it will save a (large) .glc file in your home folder. You can then play or encode it. For complete list of available options see

glc-capture --help


To play a captured stream directly, execute

glc-play [stream file]

ESC stops playback, f toggles fullscreen and Right seeks forward.


In order to use the videos outside of glc-play, you will need to encode it. Here are a few example that work well for encoding. Of course, you can be creative and use any of the formats supported by ffmpeg to get your desired result (mencoder works too, I'm just not familiar with it).

For either script, run with the following context (assuming it's saved as filename.glc

H.264 Ultrafast + FLAC Audio: (fairly quick encoding, high quality, good filesize) This script requires the following packages: ffmpeg

glc-play $1 -a 1 -o $1.wav
glc-play $1 -o - -y 1 | ffmpeg -i - -vcodec libx264 -preset ultrafast -i glc.wav -acodec flac output.mkv
rm glc.wav

It will output as output.mkv

Lossless (usually quickest, no quality loss, huge files, need plenty of HD space): This script requires the following packages: ffmpeg

glc-play $1 -a 1 -o glc.wav
glc-play $1 -y 1 -o glc.yuv
ffmpeg -i glc.wav -i glc.yuv -acodec copy -vcodec copy output.mkv
rm glc.yuv
rm glc.wav

It will output as output.mkv

WebM: This script requires the following packages: vorbis-tools, ffmpeg, and mkvtoolnix

glc-play $1 -a 1 -o - | oggenc - -b 128k -o glc.ogg
glc-play $1 -o - -y 1 | ffmpeg -i - -vcodec libvpx glc.webm
mkvmerge -o output.webm glc.webm glc.ogg
rm glc.ogg
rm glc.webm

It will output as output.webm

Note: Sometimes when recording WINE, the audio stream you want won't be #1, so you'll have to find out which one it is and experiment, and edit the encoding script accordingly. You can get some info on the streams using "glc-play -i 1 filename.glc"

External Links

  • [1] - Homepage, and they have a good wiki there as well