zlacker

The example figure shows a key hit every half second, which suggests a pecking style of typing at around 24 wpm. This way the model gets very clean waveforms. I wonder how their approach would work with average or fast typists. The sound profiles might be much harder to link to characters.

>>mxwsn+(OP)
Sovjet listened successfully to typewrites back in the 1970s.

>>zaxomi+C8
Impressive. To be fair, a lot of typewriters jam if you press more than one key at a time, plus they are very loud.

>>mxwsn+(OP)
Even if there was ambiguity, some data is better than none. Given enough training data, I suspect you could find repeatable patterns in standard typists: on a qwerty layout, after typing an "A", "Q" takes 1.2-2.3x as long to type as a "J" kind of pairwise tempo patterns. Anything to reduce the search space from brute-forcing every candidate character.

Even better if the target uses a passphrase, "hXXXse battXXX stXXXXX cXXXXXX" becomes interpretable given a few landmark letter identified with high probability.

>>mejuto+Cb
What's more impressive that the vibration of the glass windows can be used, too.