If the codecs are not used by the media player it won’t play the video. Just like any other media player, QuickTime on Mac also examines both the audio and video codecs within the video file whenever you open any file on Mac.
Image Source: Why AVI Files don’t Play on Mac? So, before we get to know how to play AVI files on Mac or how to fix AVI files that are not playing on Mac, let’s get a quick look at Audio Video Interleave (AVI) format. In some cases, even if the required codecs are available, the AVI video file does not play due to corruption. None of the four major Indeo codecs that are required to decode AVI files have been integrated into QuickTime. Playing AVI files is one of the biggest worries for a Mac user. How could I fix this because I want to play these files with QuickTime?
