Is it possible to measure distance to object with camera?

Question

Is it possible to measure distance to object with phone camera?

I mean, in my application I start the camera, facing the camera to the object (lets say house) and th

Answer 1

I think it could be possible doing that using the phone camera. I know that the modern phones use lenses to focus on a object. If it is possible to know their focal length and their position(displacement) to focus on the chosen object it's also possible to determinate the distance.

Answer 2

You have the angle in the phone's accelerometer. If you calculate the tangent of this angle and multiply it by the height of the camera lens, you get the distance.

Answer 3

No. Only with two cameras in stereo mode, like the xbox 360 kinect. It takes at least 3 points to triangulate distance.

Answer 4

Nope. The camera can only give you image data and an image alone doesn't give you enough information to give you depth information. If you had multiple images that you had location information for or even video you could then process it to triangulate the distance, but a single image alone would not be enough to give you a distance.