Script to strip various iTunes atoms from purchased AAC files via AtomicParsley.

stripiT.rb

#!/usr/bin/env ruby

# usage: stripiT.rb file1.m4a file2.m4a file3.m4a
# automatically outputs to file1 - stripped.m4a, file2 - stripped.m4a, and so on.

# Script to remove extraneous/unwanted atoms from iTunes purchased files by way of AtomicParsley.
# Output should be comparable to the atoms left over after reencoding the file in iTunes itself.
# I only care about songs, so I have no clue how well this applies to video files
# Some information taken from: https://code.google.com/p/mp4v2/wiki/iTunesMetadata

# atoms to remove:
# moov.udta.meta.ilst.apID # apple account email address
# moov.udta.meta.ilst.atID # artist-track ID
# moov.udta.meta.ilst.cnID # iTunes Catalog ID
# moov.udta.meta.ilst.geID # genre ID
# moov.udta.meta.ilst.plID # playlist ID (identifies album)
# moov.udta.meta.ilst.sfID # iTunes store identifier (location/number)
# moov.udta.meta.ilst.cprt # copyright information
# moov.udta.meta.ilst.flvr # bitrate/video size information?
# moov.udta.meta.ilst.purd # date purchased
# moov.udta.meta.ilst.rtng # Explicit/Clean information
# moov.udta.meta.ilst.soal # Album sort name
# moov.udta.meta.ilst.stik # media type information
# moov.udta.meta.ilst.xid  # vendor xID
# moov.udta.meta.ilst.----.name:[iTunMOVI] # some embedded plist thing, contains filesize and flavor.
# moov.trak.mdia.minf.stbl.stsd.mp4a.pinf # purchase information?

# Notes:
# [pinf] contains personal info, such as the name attached to the apple account.
# 	It requires --DeepScan to remove.
# [apID] contains the email address attached to the itunes account used to purchase.
# [purd] contains date/time of purchase
# [sfID] contains store information, including the country it was purchased in.

ARGV.each {|track|
	infile = File.expand_path( track )
	outfile = infile.gsub( /\.([^\.]+?)$/, " - stripped.\\1" )
	command = "AtomicParsley \"#{infile}\" --DeepScan --manualAtomRemove \"moov.trak.mdia.minf.stbl.stsd.mp4a.pinf\""
	["apID","atID","cnID","geID","plID","sfID","cprt","flvr","purd","rtng","soal","stik","xid ","----.name:[iTunMOVI]"].each {|atom|
		command += " --manualAtomRemove \"moov.udta.meta.ilst.#{atom}\""
	}
	command += " -o \"#{outfile}\""
	process = IO.popen( command )
	while ( status = process.gets )
		puts( status )
	end
}

I'm experiencing something perplexing with this script. Mostly works really nicely, but on about 50% of purchased items I've checked, it removes all the Apple metadata except for the name associated with the iTunes/Apple Music account. Yes, the Apple username is gone (email address), but not the first and last name of the purchaser. And I can't see any pattern in terms of when the item was purchased from Apple. I have items purchased in the last 6 months that it's removed my actual name from. And 5 year-old purchases it failed on. No error messages of any kind are seen. It runs, creates the -stripped file, and that one piece of metadata remains.