They aren't; AVI videos cannot be opened in QuickTime without additional plugins. I would highly reccommend installing VLC and using that instead of finding plugins for QuickTime.
.avi files are mainly video files. It can be played through Realplayer and also Apple Quicktime.
PowerPoint only accepts .avi,.asf and .mpeg video formats.
There are several video converters which you can easily download and use in order to convert quicktime video to avi.
I'm pretty sure Quicktime Pro can do it, and it only costs $30. If you're using iMovie, then I think it can handle avi's, though. Try Handbrake or MPEG Streamclip
Mainly .Mov files are opened in Quicktime Player by Apple and VLC player. You can get the download link below.
Might be from the video format of the video you uploaded. You can only upload files in either QuickTime .MOV, Windows .AVI, or .MPG files. If you did, then it might only need time to process.
Quicktime plays MOV and QT files. If you have Windows 7 media player, then you can't play QT or MOV files on it. You need to convert the files to one of the following file name extensions:.asf, .avi, dvr-ms, .m1v, .mp2, .mp2v, .mpe, .mpeg, .mpg, .mpv2, .wm, .wmv
avi files are actually already video files.
There are no benefits of transferring files from an MP4 to an AVI. There are benefits of converting AVI files to MP4. AVI is an older format and more devices are designed to play MP4 files.
AVI and MOV files are video files. AVI stands for Audio Video Interleave. MOV is an apple format of a movie file.
The Perian Plug in (See links below) adds AVI (and numerous other formats) to the QuickTime player.
1,Download one AVI converter for mac 2,Add AVI files by click "add files" button. 3,By click "Effect", "Trim", "Crop" or "Clips" to edit the output video settings. click the "Convert" button to start converting