For macOS 10.10 and later. This script will look for an image file in the parent folder of each selected track's file--presumably its Album folder in which you have previously placed an image file of some sort--and apply the data from that image file as artwork for the track.
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Exports and then re-imports selected tracks' artwork
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Check scripts downloaded to your computer from dougscripts.com for latest version
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Gather audio tracks whose files contain no artwork metadata
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Applet assists with swapping, copying, appending data between track tags
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Stop iTunes after current track is finished playing
downloaded 1h 16m 1s ago
Play the selected track and stop