I am trying to find coordinates of a line in my binary image. I used two methods.
1) X=imread('line.png'); [I,J] = find(X ==0); this methods give me multiple coordinates of the whole image.
2) A=imread('line.png'); image(A) [x,y]=ginput(); this methods give me the coordinates of the points on the line that I click by mouse.
Using method 2, I click multiple points (between start and end point of the line) and I get coordinates of those points. But when I compared the results getting from method 2 and method 1, they are different. I know that the cooridinate points may be different depending on my clicking. But I think the start and end coordinate (i.e. start and end of the line) should be the same?
Can anyone help me what the difference between these two methods? Are they finding different coordinate system?