# Aerial Picture Ground Footprint Calculation [closed]

I've been working on an application that, given an aerial picture taken by a drone and the coordinates of an object of interest, tries to determine whether the object is located within the ground footprint of the picture.

In order to achieve this, I'm trying to figure out what the most accurate way to compute the ground footprint of an aerial picture is.

My understanding is that the image is nadir, the footprint can be calculated as follows:

footprint_width = sensor_width * altitude / focal_length

footprint_height = sensor_height * altitude / focal_length

Is this correct?

If the picture wasn't taken perpendicularly, how do pitch, yaw, and roll factor into this calculation?

• Yes for first question (within reasonable altitude limits), rest is fodder for math.stackexchange.com (spherical trigonometry). Apr 23 at 7:40
• Does this answer your question? How do I calculate the ground footprint of an aerial camera? Apr 23 at 12:27
• @SaaruLindestøkke some have commented on that question explaining that the accepted answer is incorrect, so that doesn't answer my question yet Apr 23 at 12:39
• That's a pity, the comments also mention "This answer is incorrect and only works with a 0º gimbal pitch and roll (x, y)". Your case is when the pitch and roll is 0, right? There's also this other question, does that help? Apr 23 at 14:01
• I’m voting to close this question because it is about using the camera as a measurement device, and not about the art, science, or business photography.
– scottbb
Apr 24 at 16:13