[FFmpeg-user] Controlling moov atom file size

Werner Robitza werner.robitza at gmail.com
Wed Aug 14 20:38:56 CEST 2013

> It was suggest by the tech team that moov file is large and it should
> reduced below a certain threshold.

Unless they can't tell you what exact size the maximum is, I doubt this
will significantly decrease the latency.

> Somewhere in mails on this user group i also read that there is another
> flag "-movflags faststart" which can be used to achieve similar purpose.

This moves the moov atom to the beginning of the file, which is essential
for streaming. Otherwise you'd have to download the entire file before the
player could start showing you video.
You should always do that when preparing content for streaming.

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