[FFmpeg-user] FLV Keyframes meta data for blind seek-ahead

Jesse Gordon tojesseg at gmail.com
Mon Nov 12 08:09:06 CET 2012

Good Day,

I'm trying to set up my web player (like osflv, flowplayer, jwplayer, 
etc) to be able to seek or jump ahead to a portion of the video which 
has not yet been buffered over the internet. You know, like jumping to 
near the end of a youtube video that hasn't finished buffering yet.

 From what I can tell, in order for this to work, the flv file must have 
a keyframe list inserted into the meta data so that the player knows 
that (for example) frame 500 will be at byte offset 150000 or whatever, 
so it can request the HTTP server to start at an offset of 150000 bytes, 
and land on a keyframe.

So my question is does ffmpeg support this, and if so, how can I verify 
that it's doing this?  From my searching, people use flvtool2 to insert 
the keyframe list into the metadata, but flvtool2 seems to not work for 
me. (It's a ruby thing that's not compatible with Slackware I guess.)
Seems like ffmpeg might support this since it's such an amazing program!

Thank you very much,


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