A bit of fun: I put my limited Applescript skills to the test and whipped up a droplet that will strip the first 492 bytes out of the .itc files, thereby making them back into JPEGs (or PNGS, although the type code and extension will be set to those of a JPEG)
Please note that there is no error checking done by this script and it assumes that the files you are dropping on it are iTunes-downloaded ITCs as found in ~/Music/iTunes/Album Art/Download/. In turn, the script will create JPEGs on your desktop in the format “Cover1.jpg”, Cover2.jpg”, etc. If, for some reason, you already have files with these names on your desktop THEY WILL BE OVERWRITTEN WITHOUT WARNING. With that out of the way, here you go. Copy and paste into Script Editor, save as an application:
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on open (ITCfiles)
set n to 1
repeat with theFile in ITCfiles
set filRef to (open for access theFile)
try
set JPGFile to (read filRef from 493 to eof)
close access filRef
set newPath to (path to desktop as Unicode text) & “Cover” & n & “.jpg”
set newRef to (open for access file newPath with write permission)
set eof newRef to 0
write JPGFile to newRef
close access newRef
tell application “Finder”
set nullCh to ASCII character 0
set nullFourCharCode to nullCh & nullCh & nullCh & nullCh
set file type of file newPath to “JPEG”
set creator type of file newPath to nullFourCharCode
end tell
end try
set n to n + 1
end repeat
end open
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Hopefully this can help anybody who finds all their album art stuck in a “proprietary” format