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On top of this, the CPU load will probably grow to just below 100 percent, no matter how powerful your
computer is.
To avoid drop-out or jerky images in the video, it makes sense to stop any programs running in the
background - and possibly any cron jobs scheduled to run in the next few minutes - before starting to record.
Stop Recording
During recording, recordMyDesktop displays a square blue button in the system tray; clicking on the button
stops the recording. When you click the button, the program stops recording current screen activity and
immediately starts encoding the raw data (see Figure 3).
Learning Curve 3
Figure 3: Progress of the encoding process in recordMyDesktop.
Whatever you do, avoid clicking Cancel to interrupt this process; doing so will destroy the raw data.
If you have recorded a longer sequence at a high video resolution and with high-quality sound, encoding even
on powerful CPUs well above 1GHz clock speed will take several minutes.
After encoding is complete, the main window of the program again appears and prompts you to enter a path
for saving the results. By default, recordMyDesktop will choose the file out.ogg in your home directory; any
recent video player on Linux will be capable of playing the results.
The container file uses the free Theora codec for the video recording and the free Ogg Vorbis codec for the
audio signals.
Points of View
Thanks to the high-quality codecs, recordMyDesktop produces very attractive results. Audio and video signal
synchronization works without restriction, and when you play back your screen movies, you will notice that
the quality is excellent at any resolution.
In our lab, I recorded videos with a resolution of 1600x1200 pixels at a frame rate of 15 frames per second,
and then at 1280x1024 pixels, again at 15 frames per second. When I played the recordings back, they were
pleasingly smooth, without drop-out or jerkiness, and the focus was sharp - even in full-screen mode.
RecordMyDesktop returns good results with interpolated resolutions, even if you change the screen resolution
while the recording is in progress.
This kind of premium-quality video is demanding on storage capacity: 50MB per minute are required for the
raw data. Splitting the recording into several sessions makes sense, especially for longer movies. This not only
gives you more flexibility in storage space management, but also lets you divide more complex topics into
smaller chapters.
Conclusions
RecordMyDesktop finally provides a solution for creating high-quality screen movies on Linux.
Despite the relatively low version number, the software is stable and has a full set of features. The controls are
mostly self-explanatory, and there is no need to RTFM. RecordMyDesktop thus provides a useful and
efficient approach to creating training material for software rollouts.
The only drawbacks are the non-trivial free disk space requirement and the need to have a powerful CPU for a
smooth recording. Now that hard disk capacities are measured in terabytes and CPU clock speeds of several
gigahertz are the rule, these requirements might not pose a serious problem.
Learning Curve 4
INFO
[1] recordMyDesktop: http://recordmydesktop.iovar.org
[2] Istanbul: http://live.gnome.org/Istanbul
[3] Binaries for Fedora and Mandriva: http://rpmfind.net
[4] Binaries for Slackware: http://www.linuxpackages.net/pkg_details.php?id=12173
[5] Binaries for openSUSE: http://rpmseek.com.
[6] Source packages: http://sourceforge.net/projects/recordmydesktop.
Learning Curve 5
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