Where in the mp4 file structure is the duration of it?
A:
MP4 is a "container" format, which basically means it can contain a number of different audio or video streams. And each stream could have it's own duration value...
To dig out what you need, you're going to want some more reference files. I might suggest looking here and here... but you'll probably have to go searching beyond that for the different types of A/V streams you want to support.
ewall
2010-06-24 21:27:36
A:
This may not be the answer to your problem but it was to mine: http://mediainfo.sourceforge.net/
(It has a library and it's open source so you can just check for the part(s) you need)
Camilo Martin
2010-06-25 05:18:43
I'm no more looking for this, but this is probably the best answer here.
Tom Brito
2010-09-05 14:51:55
A:
As far as i know - "mp4" container is derived from the QuickTime atom structure. You can read the description of QuickTime File Format.
Parsing quicktime atoms is not a big deal (look at atomicParsley project). I'm not sure for MP4, but as for MOV-files - there's a "duration" field in "mvhd" (movie header) atom and also in "tkhd" (track header) atom. This duration is usually a number of frames multiplied by the "time scale" attribute. Time scale can be found in the same atoms.
2can
2010-07-13 00:47:21
A:
Mondain
2010-09-03 22:29:27