A respondent sits in front of the camera and answers questions that alternate between casual and topic-related, while the system produces a graph on the laptop that compares the different levels of color change on their face.
“The algorithm uses an optical technique to analyze color changes on the face, undetectable to the naked eye, and translate the pixels into signals correlated to stress levels,” HTX said, adding that the levels could be defined as cognitive stress or emotional stress. .
Cognitive stress refers to increased mental activity, such as when the interviewee is making up lies, while emotional stress can indicate fear of getting caught, irritation at being questioned, or relief after making up a good response.
“The interviewer can use the video playback feature to see what question or answer caused the subject to feel that high level of stress. Then they can decide if they want to investigate further in those specific directions” , said Vivi Chew, HTX engineer (profiling).
The role of HTX is to help users make sense of the data presented in the graph, especially since the field of lie detection is complex and subjective.
The agency is also evaluating whether it is possible to deploy the system in the field and how it can be improved. For example, the relatively large camera can be “intimidating” to an interviewee, Ms Chew said.
“Therefore, we went to the market and researched various smaller form factors, like this one that can fit in your palm, and that will help put the subject more at ease during the interview,” said she added.
The last but not least piece of technology is called the Automated Prison Screening System, which HTX calls a one-of-a-kind system that automatically collects urine samples and analyzes them for the presence of drugs.
Currently, SPS officers perform approximately 5,000 urine tests per month on supervisees placed in community programs.
The process is labor intensive as it requires officers to manually register supervisees, supervise urine collection and test the sample. They are also exposed to biological hazards.
With the new system, which resembles a portable toilet, a supervised person walks inside and the doors close and lock automatically. Their identity is verified using an iris scan and the system ensures that the date and time of the appointment are correct.
Instructions are read over a loudspeaker and displayed on a screen, telling the supervisee when to deposit their urine. The urinal itself has a shutter that automatically raises and lowers before and after sample collection. There are no cameras inside for more privacy.
The door, however, is transparent to discourage foul play. The system is also equipped with undisclosed features to prevent cheating.