3 video tutorials in The Source: 1 2 3
Each show is an hour or so, if you are only interested in cinelerra you have to search a bit around.
My starting point on the Web for learning Cinelerra by Rob Fisher.
A link page.
And the documentation page directly from the makers of that stuff which has all the above links and even the minutes for the videos. 
Note to self: search first - type later.
I use a new program called recordmydesktop. It records the current desktop or a part of it and the sound. The recording is then encoded in Ogg/Theora. The program is included in the normal Deban/Ubuntu repositories.
I start it from the commandline with these options:
$ recordmydesktop -x 200 -y 200 -width 800 -height 608 \ -s_quality 10 --no-wm-check -fps 15 -channels 2 -freq 44100 -o recording.ogg
-x 200 -y 200 are the coordinates of the top left corner of the recording area.
The height is 608 because the size has always to be a multiple of 16. I am not certain if it it is better to cut that area off in postprocessing or to scale this size down to 640×480.
–no-wm-check ignores the 3d capabilities and just records 2D
-fps 15 sets 15 frames per second as the framerate
-s_quality 10 -channels 2 -freq 44100 sets the best quality for sound in the recording. The reason why I am recording a mono mic in stereo: I have some plans that require stereo….
I have made a Desktop wallpaper to help me to see where I am recording. Only the lighter gray area shows in the recording.
There are frontends for Gnome and KDE, but there you have to draw the recording area with the mouse and can not pass the size as a parameter.
The recording is stopped by pressing CTRL-C. Then an encoding run starts.
The resulting file can be read directly by cinelerra - no further conversion neccessary like with Demorecorder.
The cinelerra options are set this way:
The rendering options are set this way:
The rendering output is then converted to the final mp4 by:
ffmpeg -i e.avi -f mp4 -vcodec mpeg4 -maxrate 1000k -b 700k -qmin 3 -qmax 5 -bufsize 4096 -g 300 -acodec aac -ab 192 -s 640x480 -aspect 4:3 mtg.mp4
Just now I am getting help from Ivan to set this last step straight.
Edit: I noticed one problem. The video and audio get out of synch after some minutes.
The project options:
The render options:
The sub dialog for video options:
The sub dialog for audio options
I get the video redered by cinelerra as an .avi (parameters will follow in an other post).
Then I use ffmpeg to convert that video to an mp4.
ffmpeg -i mtg002.avi -f mp4 -vcodec mpeg4 -maxrate 1000k -b 700k -qmin 3 -qmax 5 -bufsize 4096 -g 300 -acodec aac -ab 192 -s 640x480 -aspect 4:3 mtg002.mp4
83 MB get compressed to 14 - not bad….
There is one - perhaps something for a show?
Recording is done with Demorecorder.
Each recording is stored by Demorecorder is a seperate directory. This script converts the data to a video and wav file which can be put into cinelerra for cutting.
#!/bin/sh
# $1 is the directory name from demorec
#export from Demorec
demorec-to-avi --fps 30 \
--resolution 640x480 --output-sound-bitrate 128 \
--output-bitrate 4000 $1 tmp.avi
#
#convert video
mencoder tmp.avi -ovc lavc \
-lavcopts vcodec=mpeg4:vhq:vbitrate=6000 \
-nosound -ffourcc DIVX -o $1.avi
#
# convert audio
ffmpeg -i tmp.avi -ab 128 -ar 44100 $1.wav
#
#clear up
rm tmp.avi
meetthegimp.org has a slightly changed Wordpress standard theme. The image in the back of the title can be changed withour problem. I’ll upload the xcf.
And now the new Wordpress version is out - off course I’ll have to try that….
Here it is - a bit too compressed. But I’ll work out the paramenters on the weekend with help from John Arnold.
I think I’ll keep the titles and music as they are now. The opacity is at 50%, the white is brighter, #dddddd. The xcf files are here and here.