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How to export and encode captured stream
Please note that while glc is able to handle multiple dynamic audio and video streams, common video containers and formats usually don't. Each stream must be extracted separately. If stream configuration changes (eg. window was resized when it was captured) glc-play generates a new export file for each configuration (%d is usually substituted with export file counter in file name).
To extract information about captured streams (eg. how many video and audio streams it has), execute glc-play [stream file] -i LEVEL
where LEVEL is a verbosity level (try numbers between 1 and 6). For example with verbosity level 1, glc-play prints out something like [ 0.00s] video stream 1 [ 0.00s] audio stream 1 [ 54.87s] end of stream video stream 1 frames = 2469 fps = 45.00 bytes = 1.13 GiB bps = 21.09 MiB audio stream 1 packets = 2570 pps = 46.84 bytes = 9.22 MiB bps = 171.98 KiB
Video stream (YUV4MPEG)
To export video stream number NUM, execute glc-play [stream file] -y NUM -o video.y4m
If you have resized the window while capturing, you need to add %d to file name to recover the whole stream.
Video stream (PNG)
glc-play [stream file] -p NUM -o pic-%010d.png
Audio stream (WAV)
glc-play [stream file] -a NUM -o audio.wav
Video encoding is a complex business and if you just want a nice .mp4, use glc/scripts/encode.sh included in the source distribution package. ./encode.sh [stream file] -o mynicefragvid.mp4
It is possible export audio and video to pipe and tell encoding applications to read from pipe. It is often much faster and we are going to use it in our examples.
Part 1: transcode audio to MP3
glc-play [stream file] -o - -a NUM | lame -hV2 - audio.mp3
Part 2: read mencoder's manual
mplayer/mencoder is a huge beast and if you are going to work with videos on linux, you should definitely know mencoder. man mencoder
Part 3: use mencoder to encode video in H.264 and mix it with audio
glc-play [stream file] -o - -y NUM | mencoder -demuxer y4m - -nosound -ovc x264 -x264encopts qp=18:pass=1 -of avi -o video.avi glc-play [stream file] -o - -y NUM | mencoder -demuxer y4m - -audiofile audio.mp3 -oac copy -ovc x264 -x264encopts qp=18:pass=2 -of avi -o video.avi
Alternative encoding: quick and dirty
This method uses mencoder and assumes that you want to encode only the first audio and video track. It produces a low-quality video, for improving the quality you can try using a higher bitrate. glc-play [stream file] -a 1 -o audio.wav glc-play [stream file] -y 1 -o - | mencoder -demuxer y4m - -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=3000 -audiofile audio.wav -oac mp3lame -o video.avi
Using FFMPEG to encode glc's captured stream
glc-play test.glc -o - -a 1 | ffmpeg -i - -sameq -y audio.mp4 glc-play test.glc -o - -y 1 | ffmpeg -i - -sameq -y video.mp4
Now you can either use a video editing software of your choice to combine them when you go to edit your video or use ffmpeg to merge them together. Personally i used openshot video and imported both files together.
Alternatively: ffmpeg -i audio.mp4 -i video.mp4 -sameq test2.mp4