#!/usr/bin/env bash
flac_dir="${HOME}/flac"
opus_dir="${HOME}/opus"
#
printf 'flacs: %s\n' "$(find "$flac_dir" -name '*.flac' -type f | wc -l)"
printf 'opuses: %s\n' "$(find "$opus_dir" -name '*.opus' -type f | wc -l)"
# find "$opus_dir" -name '*.opus' -type f | sed -e "s,$opus_dir,$flac_dir," -e 's_\.opus$_\.flac_' | sort -V
printf 'diff:\n'
diff --suppress-common-lines -y <(find "$flac_dir" -name '*.flac' -type f | sort -V) <(find "$opus_dir" -name '*.opus' -type f | sed -e "s,$opus_dir,$flac_dir," -e 's_\.opus$_\.flac_' | sort -V)