Automatic infrared image distortion correction of electrolytic cells based on refined edge lines

Abstract

Lens distortion greatly affects electrolysis fault location based on infrared images. This paper proposes a lens distortion correction method for the infrared images of electrolytic cell groups (ECGs) based on refined edge lines in a single ECG infrared image. Firstly, morphological operators are designed for ECG edge extraction, and the Hough transform method and an improved hierarchical method are combined to automatically separated the edge lines. Then, the least squares method is applied to refine the lines, and an optimization solution model is designed to calibrate the distortion parameters according to the refined lines. At last, an interpolation strategy is presented to restore pixel values of the corrected images with high speed and quality. The proposed method obtains a root mean squared error of the corrected lines of about 0.014 pixels, which is advanced and meets the fault location need. Moreover, high effectiveness is obtained with the proposed interpolation strategy.