OS X 10.8 or 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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Perform search-and-replace on text in your choice of tags
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Copy chosen tag info from one set of tracks to a different set of tracks
downloaded 32m 11s ago
Use tag data to formulate new file name for selected tracks' files
downloaded 37m 14s ago
Exports and then re-imports selected tracks' artwork
downloaded 39m 28s ago
Convert or import tracks with any encoder on the fly
downloaded 58m 16s ago
Batch-append text to comments