How would you find the height of objects given an image?

Question

This isn\'t exactly a programming question exactly. I just want to know what your approach would be to a common problem in Digital image processing.

Let\'s say you

Answer 1

Assuming they're all the same distance away, all to scale, you'd want to find a single unit of measurement you can guarantee. For example, if there's a person in the photo, again, same scale, and you know they're exactly 6 feet tall, you use that as your measure. You then take that, and count how many stacked make the tree. For example, if you need 3.5 of this person, then:

3.5 * 6 = 21

gives you a 21 foot tall tree.

Without a single point of reference for everything, or if they're all on different scales, you would need a lot more information than you could easily get without having been there.