Description taken from xmount project site on Pinguin's HQ:
xmount allows you to convert on-the-fly between multiple input and output harddisk image types. xmount creates a virtual file system using FUSE (Filesystem in Userspace) that contains a virtual representation of the input image.
The virtual representation can be in:
Input images can be:
In addition, xmount also supports virtual write access to the output files that is redirected to a cache file. This makes it possible to boot acquired harddisk images using QEMU, KVM, VirtualBox, VmWare or alike.