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[SOLVED] Whats the easiest way to add album art to a file with ffmpeg?
Use Picard from musicbrainz. Its Foss and available on most Linux distros. Even windoze/mac, idk, most likely it'd be there. The GUI is self helpful or maybe watch a YouTube video explaining it. Otherwise try searching for a album tagger application, I remember there was something like Kid3, but Picard is more than enough.