-# POSIX.1-2017, Base Definitions, 3.282 Portable Filename Character Set says
-# [A-Za-z0-9._-]
-# https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap03.html#tag_03_282
-
-# Flac tags (set with `flac -T fieldname=...`) are Vorbis comments.
-# https://www.xiph.org/vorbis/doc/v-comment.html#fieldnames field names we care about:
-# - TITLE - Track/Work name
-# - VERSION - may be used to differentiate multiple versions of the same track title in a single collection. (e.g. remix info)
-# - ALBUM - The collection name to which this track belongs
-# - TRACKNUMBER - The track number of this piece
-# - ARTIST - The artist generally considered responsible for the track
-# - DATE - Date the track was recorded (XXX I use US release date)
-# I use one more, though I'm unsure where I got it. Did I make it up?
-# - DISCNUMBER - number in multi-disc collection
-
-# Input is a directory containing:
-# - trackNN.cdda.wav - WAV format files ripped from CD-DA audio tracks where NN is track number 01 - 99
-# - tags - described below
-# - cover.front.jpeg - optional JPEG format file containing the album front cover
-
-# The tags file is composed of two blocks:
-# 1. album tags
-# 2. track tags
-# Album tags may be:
-# - ALBUM
-# - ARTIST
-# - DATE
-# - DISCNUMBER (optional)
-
-# Track tags may be any of the rest of the tags listed above, suffixed with
-# [N] where N is the track number. ARTIST, and only ARTIST, may also appear
-# in the track tags. In this case, it overrides the album artist. In order
-# to add artists, the album artist must be listed again. For example, Reba
-# McEntire's "The Heart Won't Lie" on the album "It's Your Call" features
-# Vince Gill, and is specified as:
-# ARTIST=Reba McEntire
-# ALBUM=It's Your Call
-# TITLE[5]=The Heart Won't Lie
-# ARTIST[5]=Reba McEntire
-# ARTIST[5]=Vince Gill
-