Abstract: Because the LSD (Line Segment Detector) algorithm, when extracting continuous edges in an image, often has the problem of line segment discontinuity in results, we proposed an improved LSD algorithm based on information entropy. Firstly, the algorithm calculates the mutual information entropy between the processed image and the original image to determine the number of layers of gauss pyramid and the number of images in the layers, to build an adaptive Gaussian pyramid. Secondly, the improved otsu threshold is used to divide the image into different regions according to the gradient peak value of the image,and the corresponding gradient threshold is calculated to separate the image background. Finally, line segments are found according to the gradient angle and verified by helmholtz criterion. The simulation results show that the algorithm solves the problem of LSD algorithm in extracting the discontinuous line segments. Compared with other popular algorithms Hough Transform, PPHT(Progressive Probabilistic Hough Transform), LSWMS(Line Segment detection using Weighted Mean Shift), LSD, EDLines, more meaningful Line segments were extracted.

Key words: line segment extraction, Gaussian pyramid, information entropy, adaptive