[FFmpeg-user] filter thumbnail does not respect aspect ratio

[Carl Eugen Hoyos]

Thomas Seilund <tps <at> netmaster.dk> writes:

> 16:9 video:
> 
> ffmpeg -i p20120122142736.mpg -ss 0 -vf thumbnail 
> -frames:v 1 thumbnail.jpg

I suspect you want to use -vf thumbnail,scale=iw*sar:ih 
to get an output file with sar=1:1 which will be displayed 
as expected by applications that ignore the JFIF aspect.

Carl Eugen