The following tools are used to develop this backend:
Bochs - PC emulator on which I have installed Windows and the Genius scanner driver, so I could do scans on a Linux host (and trace them.)
bochs-trace_parport patch - Patch to Bochs to allow parallel port sniffing and direct access to the host system's parallel port. On the above directory you can find the first (more verbose) and second (less verbose and compatible with the trace2c.sh filter) versions.