camera detect my position

Can you tell me how can I get that a camera (or webcam) follow my position when I move? many thanks

Mount the camera on a servo or two. Use an Arduino and the servo library to take commands from the serial line. Use something like RoboRealm or OpenCV to send the Arduino commands, based on the processed image.

Thank you:

but how I get the position? will I need some sensor? if yes, can you tell me wich one?

many thanks again

You're going to have be more specific. You need to say what the environment is, how big it is, what performance you expect...

Your thread title suggest that the camera does the detection, though tracking moving objects with a moving camera can be tricky.