Investigation of Defects in Insulators via Infrared-Visible Multispectral Methodology

It is important to discover the defects in insulator used in power transmission lines. In this study, infrared (IR) camera combined with a visible light camara was employed to detect defects in insulators under service conditions. Scale-invariant feature transform (SIFT) was applied to integrate the IR images and the visible light images, which were captured by two different cameras, respectively. After employing feature point recognition, feature matching, bilinear interpolation algorithm, and nonsubsampled contourlet transform (NSCT) to process the images, the combined picture can clearly indicate the positions and the severity of the defects. The results indicate that the combined IR and visible light camaras can be effectively applied for inspection for power gride transmission lines.