puddletag is a tag editor for Linux loosely based on mp3tag. It uses a table layout so that all the tags you want to edit by hand are visible and easily editable. puddletag excels at automating repetitive tasks like extracting tag information from filenames, tagging files from a text file or the clipboard, renaming or moving files and folders based on tags by using patterns, and manipulating tags using actions and regular expressions. Supported formats include id3v1, id3v2 (.mp3), AAC (.m4a), VorbisComments (.ogg, .flac), and APEv2 (.ape). Much of mp3tag's functionality has been replicated with added enhancements and tweaks.
Flac-utils is a toolkit for managing FLAC files. Its primary usage is syncing metadata between sets of FLAC files. Flac-utils also provides a Python module called flac_compare that can be used separately. The utilitiy consist of three tools: flac-sync, which syncs a file tree of FLAC comments for files with the same audio-part; flac-diff, which compares two FLAC files' metadata information and shows the differences; and flac-add-picture, which adds album cover art to the files using Amazon.