Contrast Enhancement and Pseudo Coloring Techniques for Infrared Thermal Images

Infrared thermography is a non-invasive and noncontact type radiometric approach that is widely used in medical diagnosis and many other fields. The thermal camera provides the temperature variation information in the form of 2D false color image (or thermogram). These thermograms are either grey scale image or pseudo color image. Grey scale images have poor contrast and difficult for human interpretation. So, there is need of some algorithms to process the image to improve the geometric information of the Region Of Interest (ROI). Various pseudo coloring and contrast enhancement algorithms are developed to improve the visual appearance of the thermogram. In this paper, the overview of some contrast enhancement and pseudo-coloring algorithms with future directions are discussed. In addition, the basic introduction of infrared radiations, thermal imaging, contrast enhancement and pseudo coloring are included.