If you want to edit MPEG 1 files then no decoder is required. If Video Edit Magic prompts you to convert the MPEG file then it is a MPEG 2 format.
Try opening this file in Windows Media Player. If you are able to playback the file without any problems then you have the proper decoder installed on your PC. In this case, simply click `Cancel' when Video Edit Magic prompts you to convert the file to add the file to the timeline without converting it first.
If Windows Media Player does not correctly playback the file then you must install a good MPEG decoder. Editing an MPEG 2 file largely depends on the MPEG decoder's capability.
You can download a free MPEG 2 decoder from the following link:
http://www.deskshare.com/download/mpeg2decoder.exe
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