Search for line passing through a point in edge image
Hi all I have an color image and I converted it to gray image then I do edge detection using 'canny'. The edge image contains horizontal, vertical and inclined lines. For specific pixel (xp,yp) in the edge image, I want to search for a vertical line that pass through this point. Can anyone help me to find to a method to search or detect a vertical line passing in this point. Your help is highly appreciated. I started with: I=imread('image.jpg'); G=rgb2gray(I); B=edge(G,'canny'); I read about Hough transform and I found these functions but I could't write the codes or the program to solve the problem. could you please help me for more details or a part of program. your help is greatly appreciated: [H, theta, rho] = hough(BW) [H, theta, rho] = hough(BW, ParameterName, ParameterValue) peaks = houghpeaks(H, numpeaks) peaks = houghpeaks(..., param1, val1, param2, val2) lines = houghlines(BW, theta, rho, peaks) lines = houghlines(..., param1, val1, param2, val2)
Kshitij Singh answered .
2025-11-20
doc hough
BW = diag(ones(1,100)); BW(:,[20 60])=1; BW(20:90,75)=1; [H,T,R] = hough(BW); P = houghpeaks(H,200); It = T(P(:,2)) == 0; % index vector for theta == 0 lines = houghlines(BW,T,R,P(It,:)); isvline = false(size(BW)); for k = 1:length(lines) y = lines(k).point1(2) : lines(k).point2(2); x = lines(k).point1(1) * ones(size(y)); isvline(y,x) = true; end isvline(38,75) % test, is pixel(yp=38,xp=75) part of a vertical line?