[Ffmpeg-devel] ratecontrol advice

Rich Felker dalias
Tue May 10 18:06:08 CEST 2005

On Tue, May 10, 2005 at 12:55:44AM -0700, Loren Merritt wrote:
> (Warning: anything done by a 1pass encode will be an approximate/soft 
> limit, since you don't know in advance excatly how many bits a given QP 
> will take. So you'll need to fudge the limit a little if you care about 
> strict compliance.)

While true, this isn't an inherent limitation, just a flaw in lavc's
rate control engine. It's easy to implement strict limits in 1pass
encoding: just repeatedly reencode the frame at different values of qp
until you find one that gives the size you want. With binary search it
shouldn't even be that slow...


More information about the ffmpeg-devel mailing list