I am trying measure real object height from an image. I'm using the below formula
$$ \text{real height [mm]} = \frac{\text{object height [px]}\times \text{pixel size }\left[\mathrm{mm\over px}\right]\times \text{distance [mm]}}{\text{focal length [mm]}} $$
My camera is a Canon EOS 550D. My values are below:
- sensor size: 22.3 x 14.9 mm
- focal length: 30 mm
- distance to object: 1000 mm
- pixel height: 1201
I applied values in this equation but I cannot measure object.