ABSTRACT
The human visual system can distinguish hundreds of thousands of different color shades and intensities, but only around 100 shades of gray. Therefore, in a face image, a great deal of information is contained in the color, and the color information can then be used to simplify face detection and identification tasks. Although color appears to be a salient attribute of faces, past research has suggested that it confers little recognition advantage
for identifying people. However, the performance of face recognition systems varies significantly according to the environment where face images are taken and according to the way user-defined parameters are adjusted. Recognition achieved on images taken in the visual spectrum remains limited particularly in outdoor environments and at low illumination conditions. Visual face recognition also has difficulty in detecting disguised faces, which is critical for high-end security applications. The infrared face images are independent of ambient lighting and therefore have great advantages in poor illumination conditions, where visual face recognition systems often fail.
