as i wrote in the title, i would like to know, if it's possible to measure the length of a line. unfortunately it is as you can see in the attachements one long line. but i need the edge length. so i tried to detect the corners with regionprops and detectHarrisFeatures but nothing has worked yet. a scale to calculate the real length in cm is given. just to make it clear: i just need to know how i could possibly detect those corners. if i know the pixels in the corners it is, as far as i can think of, easy to calculate the pixels between.