This script will set the BPM of the selected tracks--or the tracks of the selected playlist--to "1" if the track contains artwork.
Thus, you can then create a Smart Playlist utilizing "BPM is 1" to include tracks with artwork.
This script is not for everybody, and certainly not for users who utilize the BPM tag for its intended purpose.
(Note: In order to launch this PowerPC-era script on an Intel machine, it must first be opened and then saved using Script Editor (AppleScript Editor pre-OS X 10.0) which is located in your /Applications/Utilities/ folder. More information is here.)
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