[FFmpeg-user] h264 encoder constant QP

vikasmk vikasmk at allgosystems.com
Tue Jul 24 07:54:54 CEST 2012

Hi ,
I am trying to get the RD plot of the ffmpeg H264 encoder (x264) 
baseline profile to use it as a comparison against our companies h264 
encoder . As I understand , I need to disable the RD loop and get the 
PSNR and bitrate values at various values of QP ( 10 to 51 ) .

I tried setting the qp constant with  -qscale 10 . But ffmpeg seems to 
be overridding the qp values and is not using the constant value of 10 . 
I need a way to set qp constant and disable the RD loop. Or any work 
around that would give an rd plot .
the flags I use are
flags : "-vcodec libx264 -profile:v baseline -qscale 10  -refs 1 "

ffmpeg version :
./ffmpeg -v
ffmpeg version N-42619-g6b7849e Copyright (c) 2000-2012 the FFmpeg 
   built on Jul 20 2012 20:06:49 with gcc 4.5.2
Any help would be appreciated.

More information about the ffmpeg-user mailing list