Creating training videos with recordMyDesktop
Clicking the recordMyDesktop entry in the menu launches the program and shows a preview of the current desktop in a small window. The Video Quality and Sound Quality sliders – both set to a maximum value of 100 – can be changed here.
Clicking the Advanced option takes you to more settings, such as the frame rate or the sound card sampling rate (Figure 2). Normally, you will not need to modify these values.
At the bottom left of the program window, you will also see a Select Window button, which you can use to select the window drawn by an active program. After you click the button, the mouse pointer changes to a small cross; now click the active application window on the original screen.
RecordMyDesktop draws a red frame around the window in the preview and you can immediately see which activities you are recording. If you mistakenly enable the wrong window, just right-click the preview image to revert to your previous selection.
Besides this, you can also record a specific screen area by selecting the area with the mouse in the preview.Clicking the Record button starts the recording.
RecordMyDesktop then takes snapshots of the desktop at the preset frame rate and – assuming you enabled the sound option – records the sound at the same time. Clicking Quit quits recordMyDesktop.
The recordings generate a fairly substantial volume of data, so make sure you have enough space for this on your hard disk. What you also need to take into consideration is that the space requirements skyrocket if you have a high screen resolution. And higher audio sampling frequencies will consume even more space.
Because recordMyDesktop does not typically encode the data it collects on the fly (preferring to do the job later), you need twice the amount of disk space to be able to convert the recording later. Making sure you have several hundred megabytes of free disk space for a recording of just a couple of minutes is a good idea.
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.
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).
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.
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