How do you convert an entire directory with ffmpeg?

Question

How do you convert an entire directory/folder with ffmpeg via command line or with a batch script?

Answer 1

I'm using this one-liner in linux to convert files (usually H265) into something I can play on Kodi without issues:

for f in *.mkv; do ffmpeg -i "$f" -c:v libx264 -crf 28 -c:a aac -b:a 128k output.mkv; mv -f output.mkv "$f"; done

This converts to a temporary file and then replaces the original so the names remain the same after conversion.