An Algorithm for Extracting Lines and Circles with High-Speed and Accuracy

This paper presents a fast and accurate algorithm for extracting lines and circular arcs from digital images. Conventional line and circle extraction algorithms first extract the edge pixels and then connect these edge pixels into lines or circles. In contrast the proposed algorithm extracts the lines and circular arcs directly from the input image by tracing the perimeter of an intensity region and then using simple linear regression to compute the equations of the lines and arcs. This proposed method allows the algorithm to use the intensity information in the image to correlate the edge pixels, thus simplifying the computation of the lines and arcs and increasing the robustness in the presence of noise. Experiments were performed on a variety of synthetic and natural images (256 × 256 grayscale) to demonstrate that the algorithm can extract lines with high accuracy, while realizing an average computation time of 0.0058 seconds using a 1.4 GHz Athlon processor.