[Ffmpeg-devel] Temp data file inside libavformat

Patrick Roberts proberts9999
Thu Nov 24 06:14:38 CET 2005


  Is there any existing libavformat example for using
a temp data file when writing?  I didn't find anything
by grep'ing the source.  (There does seem to be an
example in libavcodec.)

  If anyone is interested in why or offering
suggestions:  The reason I'm asking is I'm adding
libavformat/movenc.c support for streaming 3GP and
MP4, and the mdat atom (actual movie data) is
currently written before the moov data (movie info). 
The moov data depends on values generated when the
packet pump calls write_packet, which writes the mdat
data.  For streaming, the mdat atom needs to come
after the moov atom.  I could write an external tool
to run on the ffmpeg-generated 3gp file, but I'd
rather figure out a way to do it all inside ffmpeg. 
The moov atom size can't be calculated without doing
an encode, so I can't just reserve space in the file
for it.


Thanks,
Pat



		
__________________________________ 
Yahoo! Music Unlimited 
Access over 1 million songs. Try it free. 
http://music.yahoo.com/unlimited/





More information about the ffmpeg-devel mailing list