[FFmpeg-user] amerge problem with 2-pass encoding

[Carl Eugen Hoyos]

Alex <doenerbudenchef <at> yahoo.de> writes:

> ffmpeg -y -i test.mxf -filter:v yadif -s "1920x1080" 
> -aspect 16:9 -r 25 -b:v 8000k -bt 8000k -vcodec libx264 
> -pix_fmt yuv420p -f mp4 -pass 1 -strict experimental 
> -c:a aac -b:a 320k -ac 2 -ar 44100 -ss 00:00:00 test.mp4 &&
> ffmpeg -y -i test.mxf -filter_complex "[0:1] [0:2] amerge" 
> -filter:v yadif -s "1920x1080" -aspect 16:9 -r 25 
> -b:v 8000k -bt 8000k -vcodec libx264 -pix_fmt yuv420p 
> -f mp4 -pass 2 -strict experimental -c:a aac -b:a 320k 
> -ac 2 -ar 44100 -ss 00:00:00 test.mp4

Please test the following:
$ ffmpeg -i test.mxf -y -vb 8M -bt 8M -vcodec libx264 
-vf format=yuv420p,yadif,scale=1920:1080,setdar=16:9,fps=25 
-filter_complex amerge -strict experimental -acodec aac 
-ab 320k -ar 44100 -ss 0 -pass 1 test.mp4 &&
ffmpeg -i test.mxf -y -vb 8M -bt 8M -vcodec libx264 
-vf format=yuv420p,yadif,scale=1920:1080,setdar=16:9,fps=25 
-filter_complex amerge -strict experimental -acodec aac 
-ab 320k -ar 44100 -ss 0 -pass 2 test.mp4

(Untested, sorry if there is a typo and the "[0:1][0:2]" 
might be needed, I don't think so but who knows.)

Random comments about the filter:
format, scale, setdar and fps (or -s, -pix_fmt, -aspect 
and -r) are useless in the example you gave, but I 
believe you should try to add them to a filter if you 
use it anyway, there may be a difference in the output.

Carl Eugen