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Infrared Face Recognition

systems images visual thermal

Definition: Infrared face recognition systems use infrared sensors to measure the thermal radiation emitted in the infrared spectrum range.

One of the major problems of traditional face recognition systems is constant performance under uncontrolled environments, and especially under extreme variations in illumination conditions, e.g. operating in total darkness or full daylight in an open area surveillance scenario. Such problems may be alleviated using infrared (IR) images for face recognition. Unlike conventional visual cameras, which measure the electromagnetic energy in the visible spectrum range, infrared sensors measure the thermal radiation emitted in the infrared spectrum range (0.7-0.14 µm) . Thermal images of the human face represent patterns caused from superficial blood vessels up to 4 cm below the skin surface, which transport warm blood throughout the body and heat the skin just above them by an average of 0.1°C. The vein and tissue structure of an individual is unique, even for identical twins, and thus ensures that except in case of aging, arterial problems, injury or surgery the vascular patterns acquired by IR cameras can be used for identification. Some examples of infrared face images can be seen in Figure 1.

IR face recognition systems are unaffected by variations in illumination and unlike systems using visual light, they can work without any problem under all lighting conditions, even in complete darkness. They are also unaffected by skin color, suntan, use of cosmetics and colored eye lenses or even plastic surgery. The latter, although it would defeat a visual face recognition system since it would change drastically facial appearance (e.g. facial lift, removal of wrinkles, use of silicon implants, etc), it would not affect IR face recognition, because it does not intervene with the network of blood vessels. IR systems are very robust to impostors using masks or make-up or other means of forgery, because they can readily distinguish between real and artificial skin, hair, etc, based on different values of emissivity. Nevertheless, the extremely high cost of IR sensors, makes the use of IR face recognition systems prohibitive for every day applications.

Like visual face images, thermal images are processed for recognition using appearance-based techniques like PCA, or feature based techniques that locate and use features like the corners of the eye where the upper and lower eyelids meet (canthi), the curves produced by the main facial arteries of the two cheeks, the position and angles of main arteries under the forehead, etc. Contour matching techniques are also suitable for IR recognition. The use of multimodal visual and IR face recognition systems has also been proposed.

Infrared Photography - Light and Heat: Near and Far Infrared, Near-Infrared: Light We Cannot See [next] [back] Information Technology and Virtual Communities - INTRODUCTION AND BACKGROUND, INFORMATION TECHNOLOGIES, CRITICAL ISSUES, CONCLUSION

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about 6 years ago

first let me say thank you for giving the opportunity to express my failure in getting the federal government involved that resulted from a medical implant called an EPAM, as a result of the LA County Sheriffs beating. that is neither here or there but i have learned to pass on what i have learned. the cranial nerves can lead to locations on the human body from your eyes to the archilles and feet and toes. the it is based on the medcial alert system 62. and then off on the "EBS" 15KB system. it is a microprocessor and it ables the sheriffs to trck me 24/7 and i have an EEG range of 18-25 low amplitude, to 25-24 gamma. the United States Justice Dept. cannot get the medical records because i am now suffering strokes and i have been able to catch infra-red pictures of my face with infra-red eyes use the light factor guide R0 &R1 which gives one a 6& 8 for eyes and ears. my face is extremely ugly in the facial recognition. good luck. one last note the sheriffs are able to piggy back off of my signal and their actions and conduct i have reported the the FBI, hopefully i will get a response to testify against the Sheriffs because it is a massive invasion of privacy from them knowing your social security number and all activities are double....good luack...ernieV.