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MP4 container format specification, Trying to write a low memory parser
saratoga
post Jan 10 2009, 22:41
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I've been working on making an mp4 parser for AAC files more memory efficient for targets with very little RAM. Unfortunately, just looking at source code for various parsers its somewhat difficult for me to see how the container actually works.

I've tried google but have found surprisingly little in the way of a detailed specification. Could someone recommend one to me?
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Lear
post Jan 14 2009, 12:00
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The QuickTime documentation from Apple is what I used when I worked on the MP4 parser in Rockbox. There are no headers or similar in the mdat box that I'm aware of, so you have to rely on the stsc, stco, stsz and stts boxes (atoms) to locate individual frames, map frames to time, etc.

If you are working on MP4 seeking in Rockbox, I have some ideas on how it could be improved (to reduce memory usage) in case you're interested. smile.gif
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