VCDs and SVCDs are normally movies that were converted to this format because they can fit onto CDs rather than DVDs. As for avi format, you will need to have the right codec installed on your machine in order to watch or convert that to a VCD or SVCD. There are many softwares out that will do the trick. TMPGEnc, WinMPG Video Converter (This is what I have been using lately) DVD2SVCD or even Nero can convert them. It can get a bit tricky to do though. Hope this answers your questions.........
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