[FFmpeg-user] Automatically scaling videos and adding padding

[Francesco Turco]

> Why don't calculate with other tool? "bash" or "bc"? Ffmpeg is a video
> processing tool, calculating shouldn't its main function, I think.

Yes, I could do as you suggest, but that way I have to manually tell the
bash script the resolution of the source video. FFmpeg, instead, is able
to determine it automatically, and provides the iw/ih variables which
are very handy.