A.I. figures out Prison-Language

Eine Künstliche Intelligenz hat ein Knast-Codewort erkannt. In US-Gefängnissen werden alle Telefonate aufgezeichnet und nun haben sie einen Machine Learning-Algorithmus auf diesen Datenberg angesetzt. Interessanterweise haben sie die A.I. nicht auf die Audiodaten trainiert, sondern auf die visuelle Repräsentation als Wellenform, und haben quasi Image Recognition-Mechaniken auf Sprache und Audiodaten angewandt. Und prompt hat die KI ein Codewort geknackt – „Threeway“ – mit dem Knastis Telefongespräche mit „nicht genehmigten Personen“ anleiern: Prisoners’ code word caught by software that eavesdrops on calls.

Every call into or out of US prisons is recorded. It can be important to know what’s being said, because some inmates use phones to conduct illegal business on the outside. But the recordings generate huge quantities of audio that are prohibitively expensive to monitor with human ears. To help, one jail in the Midwest recently used a machine-learning system developed by London firm Intelligent Voice to listen in on the thousands of hours of recordings generated every month.

The software saw the phrase “three-way” cropping up again and again in the calls – it was one of the most common non-trivial words or phrases used. At first, prison officials were surprised by the overwhelming popularity of what they thought was a sexual reference.

Then they worked out it was code. Prisoners are allowed to call only a few previously agreed numbers. So if an inmate wanted to speak to someone on a number not on the list, they would call their friends or parents and ask for a “three-way” with the person they really wanted to talk to – code for dialling a third party into the call. No one running the phone surveillance at the prison spotted the code until the software started churning through the recordings. […]

The company’s CEO Nigel Cannings says the breakthrough came when he decided to see what would happen if he pointed a machine-learning system at the waveform of the voice data – its pattern of spikes and troughs – rather than the audio recording directly. It worked brilliantly.

Knast-Sprache auf Nerdcore:
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