[theora] Key frame bitrate

Andreas Engel
Wed, 09 Feb 2011 07:39:02 -0000

Hi,

I'm using Theora for live video chat. My problem is, at higher bitrates
the bandwidth peaks caused by key frames are so high that most key
frames get dropped in UDP traffic. The peaks are so strong that I still
get many packet loss artifacts when sending with 1Mbit/s bitrate on a
2Mbit/s connection. I measured delta frames to be around 12kbyte and key
frames up to 100kbyte in 1280x720 video at 15fps even with lowest rate
buffer settings.
I can send 2Mbit/s without errors when using heavy traffic shaping, but
this causes clearly visible delay.
In pre-1.0 API there was a parameter to set the bitrate for key frames
which would probably help a lot with this. Is there any chance key frame
bitrate control finds its way back into Theora? Or any other workaround
for this?

Thanks in advance
Andreas