Starting 2 yrs. ago I painstakingly went out on web image searches to copy all missing and incorrect album art in iTunes. My library is over 1,000 cd's and nearly 30% needed inclusion or editing, to give you the scale of the task, especially on some obcscure classical recordings. This was after purging all non essential MP3's and ripping my entire library in ALAC. All are now correctly represented and accounted for in iTunes but many are still missing in my SONOS controller. When looking into Windows Explorer files those same covers missing in SONOS are un-thumbnailed in the Windows files. I am sure it is a sizing issue when copying and pasting into iTunes, it is not an issue in iTunes and is in Windows.
As I wait for delivery for my PS Audio Bridge II that will be served by the JRiver controller, and before I go through the time consuming task of redoes on the album art, the Q is:
Does JRiver pull the album art from the meta data in the Windows file or out on the web? And what are the sizing requirements?
The good news for me is that if I do need to replace resized unrepresented artwork in Windows I can isolate the ones needing attention by looking in the SONOS app under Albums instead of back and forth in Windows. The file extensions for album art are encrypted to an unrecognized format in any of the many graphic and photo programs I own (itc2).