[FFmpeg-user] mp4 settings

Austin Murphy austin.murphy at gmail.com
Mon Jul 18 19:04:23 CEST 2011

On Thu, Jul 14, 2011 at 6:25 PM, HallMarc Websites
<marc at hallmarcwebsites.com> wrote:
> I am writing a PHP script using ffmpeg to transcode uploaded video files to
> mp4.
> ffmpeg -i INPUT_FILE -f mp4 -vcodec libx264 -r 25 -b 864k -acodec libfaac -s
> 480x320 -aspect 3:2 -qscale 1 -ac 2 -ar 44100 -ab 96k -async 1
> Make sure it is set for streaming
> When I use SUPER the file it outputs is playable on everything I have thrown
> at it and I'm not getting the same result with my ffmpeg settings. What am I
> doing wrong?

An MP4 file is not really streamable until you run  qt-faststart  on it.
There is some component of the file that is written at the end of the
file when the encoding is completed.  To stream, that component needs
to be moved to the front of the file.  That is all qt-faststart does.


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