[Mp4-tech] Necessity of IODS

[Praveen Singh]

Hi all,
I am working on mp4 parser library.
When standards says that mp4 follows the Object Descriptor Framework and
Initial object descriptor serves as the starting point of this framework,
why the  "iods" box/atom is not Mandatory in mp4 files?
How the Object Descriptor Framework is maintained in case of absence of
"iods" box in mp4 file?
Thanks in anticipation
Praveen
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