By default when you create screencasts using recordmydesktop in Linux (Ubuntu specifically), the output is an OGG container file. As anyone who has tried to bring that file into Windows quickly learns, there’s not too much software out there that will “understand” OGG in Windows, and even less available if you want to edit it later on using your video editor of choice in Windows (or Mac for that matter).
So in the end you have to find some way to convert OGG to AVI while still retaining quality both for audio and video just to edit it.
While it’s true you can use ffmpeg from the command line in Linux to convert the file from OGG to another format, audio/video sync isn’t always the best and furthermore the quality is vastly inferior compared to the original OGG.
This article shows you how to get full quality conversions for OGG to AVI, both for video and audio – in sync.

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