mount image file

sudo modprobe loop

sudo losetup -f
this returns a new loop device (e.g. /dev/loop4) which can be associated to the image

sudo losetup /dev/loop4 image.img

sudo partprobe /dev/loop4
creates the devices /dev/loop4p1 etc. (for each partition)

sudo mount /dev/loop4p1 /tmp/loop4/