iTunes U only accepts files for upload that are less than 500 megabytes (MB). Audio files must be either AAC or MP3 with appropriate file extensions (.m4a, .mp3). To use specific cover artwork with an audio track, use the AAC file type format (.m4a). Video files must be MPEG-4 with H.264 compression with appropriate file extensions (.mp4, .m4v, .mov). If you are using QuickTime to create and edit video content, export your videos by choosing Movie to iPod from the Export pop-up menu in QuickTime Pro.
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