This is an active capacitance swipe-type device similar to but smaller
than the AES2501.
Image processing performance is good but matching performance is not so
good. The bozorth3 matcher needs tweaking in order to better cope with
small sets of minutiae.
With a lowered threshold, matching performance is good enough for now.
This driver works quite nicely. Seems a little too sensitive though (too
much black in the standardized image, not enough ridge gap definition).
Processing results are quite good, but you need a good enrollment image
(i.e. long!). It's best to get such images by pressing harder than you
might think necessary and swiping slowly.
Added new API functions to obtain images, even when scans are bad, perhaps
a useful way to show the user just how good/bad the scan actually was.
Drivers and examples updated accordingly.
Drivers now have an ID number. These will be assigned by me and documented
on the wiki. 0 cannot be used.
Drivers now define a devtype for each device they initialise. This is to
cope with the situation where a driver can support varying devices where
their print data is incompatible (i.e. image scaling is totally changed).
This doesn't apply to any existing supported devices.
Print data no longer includes driver name, and includes driver ID instead.
Paths to saved print data now include driver ID and devtype, and no longer
include driver name.
APIs exposed for converting a print_data into a blob which can then
be loaded back again later. Useful for systems who don't want to use
my simple storage system (which is only aimed at a single user).
File format is now defined and will be documented on the wiki. The header
is larger as we can no longer rely on directory paths in all scenarios.
Print data compat check now checks devtype and driver ID.
Daniel Drake
Anthony Bretaudeau