I want to offer the ability for an application to view a binarized
version of a scanned print. This lead onto a few changes:
1. Store minutiae and binarized data inside fp_img
2. Move resize code to the capture path, it previously happened much
later.
3. Add fp_img_binarize() to return a new image in binarized form.
4. Add a BINARIZED_FORM flag to prevent an image being binarized again.
In future, it would be nice to be able to binarize without detecting
minutiae, but this involves some work on the NBIS interaction.
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.
mindtct appears to completely ignore the pixels-per-mm input parameter
(ippmm). When processing AES4000 images, the binarized image is
completely mangled and a lot of ridge information is lost.
Resizing the AES4000's small images results in a huge imaging performance
gain.
We use imagemagick for the resizing, as it's resizing code resamples the
image too (smoothing it out), which further improves performance.
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.
