█████ ██ ██ ██ █████ ██████ ██████ ██ ██ ██ ██ ██ ██ ██ ██ ██ ██ ██ ███████ ██ ██ ██ ███████ ██████ ██ ██ ██ ██ ██ ██ ██ ██ ██ ██ ██ ██ ██ ██ ██ ███████ ████ ██ ██ ██ ██ ██████
Recently needed to rotate images based on EXIF metadata. ImageMagick to the rescue:
$ for i in *.png; do convert -auto-orient "$i" "$i"; done