Smart sensors like Upek TouchChip Coprocessor can provide scan status instead
of image, as result we need to report such status as "short scan" or "finger not centered"
from within the driver, since it's not a session error.
New driver for VFS5011 138a:0011 and 138a:0018
https://bugs.freedesktop.org/show_bug.cgi?id=61692
[vasilykh]:
- use g_get_real_time() instead of non-portable time()
- use g_free() instead of free()
- comment out "RECV(VFS5011_IN_ENDPOINT_CTRL2, 8)"
fp_dev_img_capture() is not implemented and returns -ENOTSUPP for all devices
since migration to asynchronous model. This commit implement missing functionality
Check all the drivers for one that'll drive our device in
question, and prefer ones that have a discover() method that runs
successfully to a driver without such a method.
This allow drivers to both reject devices (if 2 drivers handle
the same USB IDs), or a single driver to handle variants of the
same device (through the devtype out value of the discover method).
A subssm will be executed, and upon completion the parent state machine
will either be advanced to the next state or aborted with error, depending
on the outcome of the subssm.
Also add some debug messages.
Add timeout mechanism as an asynchronous equivalent of sleeping (uru4000
needs this).
Start implementing polling infrastructure which also accounts for pending
timeouts. We don't expose file descriptors yet, but this is a start.
[dsd@gentoo.org: some trivial changes:
fixed some warnings
fixed fp_img memory leak on error
renamed endpoint constants (calling a bulk endpoint 'ctrl' is confusing,
as a control endpoint is something different)
]
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.
The UPEK TouchChip is an active capacitance imaging device with a
press-type sensor. It also has image storage capabilities which will
hopefully be accessible through libfprint in the near future.
This device can be found in the Samsung P35 laptop.
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.