`ffmpeg` convert all files of extension to different extension

README.md

ffmpeg convert all files of extension to different extension

This snippet will (in current dir):

1. Convert all files of $first_ext extension to ones with $second_ext.
2. Remove all files with the $first_ext extension.

first_ext="webm"
second_ext="mp4"
for i in *.$first_ext; do ffmpeg -i "$i" "${i%.*}.$second_ext"; done; for i in *.$first_ext; do rm "$i"; done