[Ffmpeg-devel] qt-faststart.c

Mike Melanson mike
Wed Apr 18 18:40:31 CEST 2007

Emanuele Fumagalli wrote:
>> Do what you need to do to generate a .mp4 file. Then try streaming the
>> .mp4 file over HTTP. If the streaming does not work then you probably
>> need to use qt-faststart to move the mp4's header to the front. That's
>> all.
> Thanks for the advice, one last question,
> I noticed that when reading a large file it takes different bytes to
> start the file (for example 2Mb) , even when header is at the beginning,
> so can you confirm that the header size depends on the size of the video
> and so if I have to stream that I need to download first all that bytes?

I don't understand what you're asking. qt-faststart is rather basic. QT
muxers usually make a file that looks like this:

  | data | header |

qt-faststart takes the file and rearranges it to look like this:

  | header | data |

This is better for HTTP streaming. Will it work for your files? Try it
and find out. If it does not work correctly, the tool should tell you so
and the original file will be safe.

	-Mike Melanson

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