Research on an Improved Sobel Operator Edge Detection Algorithm for Inner Wall Rust Image Recognition of Spiral Tubes

An improved Sobel operator edge detection algorithm combined with image channel threshold segmentation is proposed to detect the corroded surface of tubes with helix. The algorithm firstly filters the image, identifies the edge of the image by the improved Sobel operator, and determines the segmentation threshold by mathematical morphology dilation and corrosion, so as to remove the pseudo-edge and extract the corroded part of the R-G channel and B-Y channel image information. The experimental results show that the algorithm can effectively extract the edge of the corroded part, and the algorithm has guiding significance for the rust identification of the inner surface of non-smooth tube parts.