hough变换找直线 matlab下能直接运行（Hough transform to find a straight line, matlab can operate directly）.docVIP

hough变换找直线 matlab下能直接运行（Hough transform to find a straight line, matlab can operate directly） Look at the effect of the upper left corner of the original, the lower left corner to find the line, right after the Hough transformation graph Clc; Clear; I=imread (test.bmp); Imshow (I) Figure I=rgb2gray (I); I_hight=size (I, 1); I_width=size (I, 2); % i_edge=edge (I,robert); I_hough=zeros (600360); For y=1:i_hight For x=1:i_width If I (y, x) ==0% coordinate transformation For l=1:360 R=x*cos (l*pi/180) +y*sin (l*pi/180); W=fix (R +300);% correction is a positive integer I_hough (W, l) =i_hough (W, l) +1; End End End End M=max (max (i_hough)); I_hough= (i_hough./m);% brightness adjustment Threshold=0.75; linear brightness threshold setting% Ih_hight=size (i_hough, 1); Ih_width=size (i_hough, 2); Temp=zeros (20,20); Count=0; For y=1:ih_hight% to find those high brightness line For x=1:ih_width/2 If i_hough (y, x) threshold Count = count+1; Temp (count, 1) = x; Temp (count, 2) = y; End End End Imshow (I) Hold on For i=1:count% draw words % y=kx+b K = Tan (Temp (I, 1) *pi/180); B = (Temp (I, 2) -300 (/sin) temp (I, 1) *pi/180); For j=1:360 X (J) =j; Y (J) =-x (J) /k+b; End Plot (x, y) Hold on End Axis equal Figure Imshow (i_hough) The following is the theory Hough transform is used to find the lines in an image. Its principle is very simple: Each point on the line can meet the normal equation p=x*Cos +y*Sin theta theta (1), P is the origin of the coordinate system to the straight line distance, theta is linear L vertical shaft angle and X. Image X Y space in a straight line with the polar coordinate space O P theta point in a one-to-one relationship. Note that this correspondence, a point in X-Y space corresponds to a curve of the polar coordinates in space (can be regarded as the characteristic parameters in the XY space to represent a line) Based on this fact, we can find a line. The classic method of Hough transform is based on the requirements of the accuracy of O P thet