[Ffmpeg-devel] ratecontrol advice

[Matthew Hodgson]

Hi all,

I'm trying to use libavcodec to 1-pass encode an h.263 stream which has 
limits on both the maximum size-per-picture and total datarate.  I can't 
work out what the right way is to respect both limitations using the 
ratecontrol settings, whilst maintaining the best possible QP for any 
given frame (so long as it doesn't end up larger than X bytes - or push 
the total datarate for over Y kbits/s).

I assume I can do this with a custom rc_eq formula and/or adjusting 
qcompress - but I can't see an obvious formula for capping the 
picture-size.  Alternatively, is there another way to force ffmpeg to 
adjust the qp so that pictures are never larger than a given size?

Any suggestions would be very much appreciated indeed :)

cheers;

Matthew