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M4B File Format

MPEG-4 Audio Layer Bookmarkable File

M4B file format icon

M4B is a file extension for an MPEG-4 part 14 audio layer audio book container file format used by iTunes. An M4B file is very similar to an M4A file but specified for audio books.

M4B files support metadata for chapters and bookmarking on supporting players and most commonly uses AAC (Advanced Audio Codec).

Programs that can open M4B files include iTunes, Windows Media Player and Roxio Creator.



Learn more about M4B files:

 Wikipedia has an entry on MPEG-4 part 14

Ask an M4B questions at IT Knowledge Exchange.

This was last updated in July 2010
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My M4B files used to have pictures of the covers of the books. The pictures show up when i use iTunes but when i open them in finder in my IOS they just show a music note. This happened ever since the latest update and i wanted to know if I could get the pictures to show up again in finder.



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