By analyzing the subtle differences in the sound waveforms produced by each keystroke, the AI classifier was able to accurately determine which key was pressed during subsequent tests. The results showed a high accuracy rate for detecting keystrokes, with classifiers trained using the smartphone microphone achieving a 95% accuracy rate and those trained using Zoom reaching 93% accuracy.
However, the researchers acknowledged that the classifier’s accuracy could be compromised if users change their typing techniques. For instance, employing touch typing reduced the accuracy rate to 40-64%. They also noted that certain measures, such as adding noise to keystrokes to mask their true sound, could undermine the classifier’s effectiveness.
