How can I calculate the actual distance in real world of an object from its picture that picked up by a camera?

i want to calculate or know the distance in the real world between an object and the camera during taking a photo for this object ....what the function or code that can i use to calculate this distance from its picture that picked up by the camera?

Answer 1

[Image Analyst]

If you have the Computer Vision System Toolbox, see this link on camera calibration:

http://www.mathworks.com/products/computer-vision/features.html#camera-calibration

[marwan hasan]

i want to do my processes on the image itself that i picked it up through the camera and calculate the distance by the aid of the image .

[Image Analyst]

Yeah, so? Do you have a kinect camera or something?

Answer 2

[Dima Lisin]

With one camera, you may be able to compute the distance if you have a calibrated camera, and you know the actual size of the object. If you do not know the size of the object, then you would need a calibrated stereo camera, or an RGB-D camera.