Abstract-New way for both quality enhancement of THz images and detection of concealed objects

Vyacheslav A. Trofimov; Vladislav V. Trofimov
http://spie.org/Publications/Proceedings/Paper/10.1117/12.2189299

As it is well-known, the passive THz camera allows seeing concealed object without contact with a person and this camera is non-dangerous for a person. Obviously, efficiency of using the passive THz camera depends on its temperature resolution. This characteristic specifies possibilities of the detection for concealed object: minimal size of the object; maximal distance of the detection; image quality. Computer processing of the THz image may lead to many times improving of the image quality without any additional engineering efforts. Therefore, developing of modern novel computer code for its application to THz images is urgent problem. Using appropriate new methods one may expect such temperature resolution which will allow to see banknote in pocket of a person without any real contact. Modern algorithms for computer processing of THz images allow also to see object inside the human body using a temperature trace on the human skin. This circumstance enhances essentially opportunity of passive THz camera applications for counterterrorism problems.

We developed new real-time algorithm, based on the correlation function, for the detection of cancelled objects by using computer processing of the passive THz images without their viewing. This algorithm allows us to make a conclusion about presence of forbidden objects on the human body. To see this object with high quality we propose one more algorithm which allows to increase the image quality. Current approach for computer processing of the THz images differs from approaches developed by us early.

We apply new algorithms with success to the images captured by passive THz camera TS4 manufactured by ThruVision Inc. The distance between the camera and person is changed from 4 to 10 metres.