While there are various functions which similar usage in all the examples,
I'd prefer to keep each example to be self-containing most of the things.
However some clearly repeated action can be moved to a single codebase.
These examples have not been ported. In addition, they are also not very
useful these days, as the demo application offers a much nicer view to
view images from a sensor.
With this script it is possible to test libfprint/fprintd without any
hardware device. The image needs to be provides as a PNG with the alpha
channel storing the print data.
See the comment in the file on how the script can be used.
These PNGs were generated using gimp simply by using the greyscale image
itself as an alpha mask. The reason to do this is solely for easier
consumption together with cairo A8 surfaces.
The only API user currently seems to be the examples. fprintd has its
own storage and that will be a good idea in general.
So deprecate the API, we'll need to find a different solution for the
examples eventually.
The call to sleep(1) inside of the enrollment loop caused a crash
on at least the etes603 driver.
Because in fp_enroll_finger_img the function enters an event
handling loop. This loop needs to start before the next libusb
event timeout. Which would not happen in the etes603 driver
because the timeout there was set to 1 second as well.
When imaging support is required, we prefer to use gdk-pixbuf,
as it's already on things like Live CDs.
Also fix the examples building against the system libfprint.
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.
The basic model is that image drivers declare a fp_img_driver structure
rather than a fp_driver struct. fp_img_driver will contain primitive imaging
operations such as 'scan finger and return image'. The imgdev layer will
generically implement the primitive fp_driver operations, and the imgdev
layer will fix up the enroll/verify/etc pointers at driver registration
time.
Removed const from all fp_driver declarations, as these are now modified
dynamically in the case of imaging drivers.
Prints can now be saved to disk (but you currently must classify which
finger they are) and you can load them later.
Added 2 simple example programs to demonstrate this.
Convert enrollment function to return a signed integer, which is negative
on error or corresponds into fp_enroll_result otherwise.
Now we can treat a 'FAIL' condition differently from an actual error: fail
means that enrollment didn't complete because the data was nonsense or
whatever (e.g. scanned a different finger for each stage?).
Updated upekts accordingly.
upekts will need to know when the first enrollment stage is attempted for
the first time, so add an __enroll_stage counter which actually indicates
the next stage to enroll. -1 is a special value and it means 0 is next *and*
it is the initial attemt.
Added more debug output to the enroll handler.
Added new fp_enroll_status codes for too short or uncentered scans.
Changed the print_data allocator to consider the device rather than the
driver, this feels more natural. Added missing return value.
Make fp_enroll_status codes start at 1. 0 can now be used as a
special/temporary value by the drivers. Also check that we aren't exceeding
the number of enroll stages.
Also add a missing exit() call to the verify example and update for the
above.
