Nathan's email reminded me that there's also a dubious statement on the current 
ffmpeg page. The page references using qt-faststart to 'flatten' files by 
moving the index to the front of the file.

Indeed, qt-faststart does move the moov atom (which contains metadata about the 
video) to the front - the purpose being that video players can begin playing 
the video before it has even fully downloaded. But I don't believe that the 
correct term for this procedure is 'flattening'.

The term 'flattening a video' originates from the need to export a mac 
formatted file so it could be played in Windows, by moving all the movie data 
into the data fork instead of leaving necessary components in the resource fork 
(elements which were part of how the Mac OS stored its files). One of the best 
descriptions I found is here: http://www.macwindows.com/tutfiles.html#Flattening

Also, here's a link to the qt-faststart source which has a good description 
about what it does in comments at the top: 
http://git.videolan.org/?p=ffmpeg.git;a=blob;f=tools/qt-faststart.c;h=ace4c113c88850613aff2f9158a08a6164fc6bac;hb=HEAD

I suppose it is possible that many traditional tools when performing the 
'flatten' task also moved the moov atom to the front (I haven't verified that) 
and perhaps that's why YouTube used that term in its error messages, but doing 
that alone (which is all qt-faststart does) is not flattening.

Anyway, just a nitpick.

JH

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