# losetup /dev/loop0 disk.img
# partx -uv /dev/loop0
# mount /dev/loop0p1 /media/loop1
# mount /dev/loop0p2 /media/loop2
# ...
# losetup -d /dev/loop0
==== Mount separate partition ====
# fdisk -l disk.img
Device Boot Start End Sectors Size Id Type
disk.img1 * 63 30719 28672 14M 7 HPFS/NTFS/exFAT
disk.img2 30720 31115263 31084544 14.8G 83 Linux
# echo $((63*512))
32256
# mount -o ro,loop,offset=32256 disk.img /media/loop