MPEG-4 Part 14 was based on Apple’s QuickTime container format. MPEG-4 Part 14 is essentially identical to the QuickTime MOV format, but formally specifies support for Initial Object Descriptors (IOD) and other MPEG features.
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Mobile phones use 3GP, a simplified version of MPEG-4 Part 12 (a.k.a MPEG-4/JPEG2000 ISO Base Media file format), with the .3gp and .3g2 extensions.
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