The Application of Edge Detection Algorithm in Bedload Contour Extraction

Bed load particles movement is a very complicated problem in river. Bed load sediment particle images filmed are processed by using the edge detection technology, the outline and the coordinates of the sediment particles are extracted, all of these provide the basis for calculating the bed load sediment transport rate. In this paper, the principle of edge detection and several kinds of commonly used edge detection operator were introduced firstly, then the advantages and disadvantages of all kinds of operator were pointed out, the sediment particles outline was extracted by using various operators. By analyzing the results of several kinds of edge detection operator, it shows that the quantity of sediment particles detected is the most close to the original image at the best threshold with the Sobel operator, and the image edge effect extracted is better, so the Sobel operator is the best choice when processing the images which contain sediment particles.