Voice stress analyser - Lie Detector

This Voice Stress Analyser (VSA) detects micro-tremors usually associated with a person lying. Tremors in the voice are usually due to a physiological stress response, which is often too small to detect by the ear, but may be noticeable through electronic means. After over a year of development work in my spare time, as ARM assembly language is not easy, I managed to make a voice stress analyser for the Nokia 3310. Since this phone already has voice recognition software, I was able to use some of the already existing routines for my code, through a bit of hacking and reverse engineering.

It is only for this phone as I do not have any others to test it on, and I do not have any time to develop it further anyway. I was inspired to make this because, being out of work, and bored, I used to watch the Jeremy Kyle shows where they would invoke the "Jeremy Kyle Lie Detector" test, which was great entertainment.

Concept

The idea behind it is that when you are talking to people on the phone you often do not know if they are sincere or whether they are lying, because you cannot see their face. My application enables one to switch ON the voice stress analyser during a call, which looks for micro-tremors in the voice normally associated with lying. The only limitation of the application is that only one person should be talking at any one time to obtain a clear reading. I am sure someone will soon make an app for the smartphone that does the same thing, and if you do, then remember that you got the idea from me!

Display Reading

The application displays a lie probability meter with a scale from 0 % to 100 %, where 100 % represents lie, and 0 % the truth. With a hands-free kit, it is possible to have a conversation with someone, and be looking at the meter simultaneously to see which way the needle deflects. The needle display updates every 2-seconds, and this is as fast as possible, given the processing power of the microcontroller executing my Fourier analysis code. Even though it is written in assembly language, and highly optimised for speed and size, the processing power of the Nokia 3310 is barely just enough.

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