if it has more than one track, then it is selfboot.
it looks like that image doesn't have a dummy being that the 2nd session is only 318mb. to tell if is has a dummy, open the image in isobuster or cdmage and look for a file that is huge in size. most dummies take on the filename,
000DUMMY.DAT
000A.DAT
DUMMY.BIN
0.0
0UDUMBASS.DAT (j/k)
they usually start with 0 (zero) because they need to be the first file burned alphabetically.