Camera Target size configuration

We’ve been fooling around with the Target.cpp and Target.h files to understand enough of it to see how the code determines the size of the target. After a good hour of reading through, and fact checking, we couldn’t really figure out how the values in Target.cpp correspond to the real life values of the target.

Does anyone know how the values of Major radius min and max, and minor radius min and max relate to the actual 38 inch diameter of the real life target?

The question is for understanding AND application, and any help you give us will help us greatly now and in the future.


Major/Minor radii are measured in pixels in the cameras field of view. The camera’s field of view is about 44.5 degrees. With that knowledge (and an assumption that each pixel takes up an equal # of degrees), you can compute how many pixels the 38 inch target will take up at whatever distance you’re trying to optimize for.

It takes a bit of trig, but it’s not tough to do.

See the attached image for a diagram.

wow, that was very helpful! Thank you!!

I should’ve thought about that, pixels… hmm

and i’m guessing the max pixels have to be less than the camera’s resolution?

They could be the same or smaller than.

The cameras resolution is actually how many pixels by pixels it sees.