Plotting co-ordinates using image processing.

Hello all! I would like to plot the real worl co-ordinates in matlab and plot a triangle. I have marked the point with a red marker and detected its location. But the value returned is in pixel and hence to convert it inot cm, I multiplied the x and y co-ords of the image by 0.02..still I'm not getting the correct answer. It should be 0.6 whereas the calculated value is 4. Please help me over this.

Answer 1

[Image Analyst]

Take a picture of something like a ruler and then you calibrate how many pixels equals 1 cm.