[FFmpeg-user] 2 pass CBR or VBR not really fixing the bitrate?

Moritz Barsnick barsnick at gmx.net
Sat Jul 29 23:51:59 EEST 2017


On Sat, Jul 29, 2017 at 13:16:07 -0700, Manuel Tiglio wrote:
> ffmpeg -I <input> -c:v libx264 -pass 1 -f mp4 /dev/null
> ffmpeg -I <input> -c:v libx264 -b:v avg -maxrate max -minrate min -bufsize buf -pass 2 <output> 

Have you tried using the identical video encoding settings for pass 1
and pass 2? I seem to recall that that is important.

> Can anyone post an example of a case in which ffmpeg really gets CBR or say 110% VBR?

I can't, but I can point out that ffmpeg mostly does ABR, not CBR.

Moritz


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