Elan 04f3:0c4f is mistakenly implemented as a swipe sensor instead of a touch sensor
I think this is also the reason behind #392 (closed). The verify process fails almost always, but not because of the feature extraction algorithm — instead, just because the shape of the fingerprint is messed up.
Here is an example of the scan of my right middle finger obtained by swiping.
I am sure that the sensor is supposed to be a touch sensor because on Windows it worked well by just touching it.