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Why quicktime not playing mp4 files on mac and windows pc?
It is an MP4 video file downloaded from Bluesky app. When I was trying to play the mp4 file on my Mac, this error message pops up: This file contains some media which isn’t compatible with QuickTim...
The issue you're experiencing with QuickTime not playing MP4 files is likely due to the specific codecs used in the video file. QuickTime Player natively supports certain codecs, and when a file uses incompatible codecs like VP09 (VP9) or certain audio codecs, it may fail to play.
Why QuickTime not Playing MP4 files:
- VP09 (VP9) Codec: QuickTime has limited support for VP9, which is a newer video codec primarily supported in browsers and some media players but not fully in QuickTime.
- MPEG-4 HE AAC: AAC audio is generally supported, but combined with an unsupported video codec, playback issues can occur.
- File from Bluesky app: The app may be encoding or packaging videos with newer or less compatible codecs.
QuickTime on Mac is more limited, but ensure your system is updated, or consider installing Perian (though outdated), or use native apps like Preview or Safari for web-based playback.