For macOS 10.12 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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downloaded 5m 51s ago
Search Wikipedia using the Song Name, Album, Artist, or Composer of selected or playing track
downloaded 10m 42s ago
View selected tracks, PDFs in QuickLook windows
downloaded 17m 13s ago
Copy chosen tag info from one set of tracks to a different set of tracks
downloaded 25m 3s ago
Perform search-and-replace on text in your choice of tags
downloaded 30m 37s ago
Exports and then re-imports selected tracks' artwork
downloaded 35m 48s ago
Capitalize the first letter of each word in selected track names