1 | initial version |
The first thing is you would need is to have some sort of calibration that tells you what the pixels in the image correspond to. This factor depends on your camera, lens and object distance and needs to be measured in a realistic imaging scenario.
For example if a 1 meter object exactly fits in a 512x512 pixel frame, your calibration would be (1000/512)=1.953 mm/pixel (or 0.512 pixel/mm). You can then convert pixel based displacements to real world displacements using this factor.