zlacker

>>mikece+(OP)
Fascinating. I'm really curious what the acoustic properties are that it's recognizing.

Is it more of a physical fingerprint of each key, such that if you swapped keys/springs the model would need to be updated? So it's produced by manufacturing inconsistencies, the way individual typewriters used to be forensically identified?

Or is more each key being identical, but producing a different resonance pattern within the keyboard/laptop due to the shape of all of the matter surrounding it? If you move the keyboard in the room, do you have to re-train the model?

I also wonder how much it varies depending on how hard you press each key -- not at all or a great deal? And what about by keyboard -- when you compare thin MacBook keys with an external full-height keyboard, is one easier/harder to recognize each key on than the other?

>>crazyg+EN
Building on what you said: (1) just the key's properties; (2) key properties relative to other keys; (2) sound transmission and environment between key and microphone; (3) relationship between key and finger; (4) relationship between key and associated dendritis