[fprint] Merging together multiple scans of the same fingerprint?

[Martin Hejnfelt]

Hi Alan,

On Thu, 2016-08-11 at 10:13 -0700, Vasily Khoruzhick wrote:
> Hi Alan,
> 
> On Thu, Aug 11, 2016 at 10:03 AM, Alan Davidson <alan at key.me> wrote:
> > 
> > Hi libfprint folks -
> > 
> > I've got a Digital Persona U.are.U 4500 fingerprint reader, and I'm
> > trying
> > to migrate to libfprint from the closed source drivers I got from
> > Digital
> > Persona themselves.
> > 
> > The driver chosen by libfprint is uru4000, which seems right. When
> > I call
> > fp_dev_get_nr_enroll_stages on the device, it returns 1: a single
> > scan is
> > enough to enroll a fingerprint. and indeed, I can scan my finger
> > once and
> > get back a fp_print_data struct (through the callback passed to
> > fp_async_enroll_start).
> Probably you're using old libfprint. Newer returns 5. It scans finger
> 5 times and upon verification
> it compares scanned finger to a gallery.

I can verify Vasily's answer. I use the same reader with libfprint, and
it scans 5 consecutive times for enrollment, if you use an up-to-date
version of libfprint.

Regards,
Martin Hejnfelt