I'm on Emby Server OS X Version 4.0.2.0
My music library is pointed to my iTunes Music folder (~/Music/iTunes/iTunes Music/) which is then organized by artist/album/track.mp3
Each file has artwork embedded that can be displayed/edited by iTunes and other tag editors (eg Metadatics) and music players (eg PowerAmp and VLC on my Android phone playing the file copied to an SD card or from a Dropbox folder) independent of the file location. But Emby displays most of my collection as the plain colored square for albums and blank for each track.
The pattern seems to be that this happens for music I add via the iTunes interface (drag a file to iTunes and iTunes makes a copy and puts it in the right directory) or that existed in iTunes before I set up Emby.
If I add a file directly by just putting it in there myself, the artwork shows, even if this is the exact same location iTunes would put it.
Since all manner of non-Apple software can recognize and display the images, I'm starting with Emby itself as a possible culprit
Thanks!