I do not know how to edit the database file, but if you use an enigma2 receiver (I believe you are), you may try the deambox edit. It is very easy to use and you can edit channel list, radiolist, IPTV list... It is a Microsoft window software.
aren't logo's in the stream (or from website) atleast I thought so because screensaver/logos changes for me on same stream
I.m back to shoutcast much easier to edit. webradioFS giving stream errors on the ones I did edit. That wasn't the case before.
/etc/ConfFS/webradioFS_favs.db