I know you can do it through BeoPort, drag and drop a photos as outlined below:
BeoPlayer supports cover art for N.MUSIC tracks, either as
pictures embedded in the tracks or as a picture placed in the
same folder as the tracks or the album.
To download or update album covers …
Cover art shows in BeoPlayer in all views on the left side of your
screen. If you have registered BeoPlayer, you have access to
BeoPortal, and after you have scanned your computer for music,
you can start updating your current album covers or downloading
album covers.
> Click and hold on the current view in BeoPlayer in the top
left-hand corner.
> Move the cursor to ‘Albums’ and let go of the mouse
button.
> Right-click an album to see the available options.
Alternatively you can drag and drop a photo onto a track or an
album directly in BeoPlayer.
When you insert a CD and click
PC CD
, BeoPlayer will show
cover art automatically, if present in the file.
BV10, AvantDVD, BS3000, BL8000, BL6000, BL4000, BL3500, BeoPorts, BC9300, BC7002, CX100s, C75s, Beo4s, BC6000s, LC2s, A9, A8s,