Image Fusion for Infrared Thermography and Inspection of Pressure Vessel

Infrared thermography is a nondestructive evaluation method with an increasing span of applications. In this paper the pixel-level image fusion of infrared light and visible light image for infrared thermography and its application in nondestructive testing (NDT) of pressure vessel are studied. First in the image fusion, different mode image registration has been done based on feature corners. The corners and curves relative to each corner are extracted using the curvature scale space method. A new shape context descriptor for each corner is computed as the criterion to match the corners. Marks can then be added to pick up the corners, especially if there are no distinct matching feature comers between the different mode images. Two fusion methods, contrast modulation and transparent fusion, are introduced to fuse the visual and infrared light images. The experimental results show that the methods are good for pixel-level image fusion. Finally the method is applied to inspection of pressure vessel. The research indicates that image fusion for infrared thermography can facilitate defect location and interpretation of inspection results.