Patent ID: 7852315

Claim:
A method implemented at least in part by a computing device, the method comprising: without knowledge of a position of any specific point of a display surface: capturing, by a mobile handheld device, optical information of a cursor presented on a presentation displayed on the display surface by a remote computing device, wherein the optical information comprises two or more images; evaluating the optical information to minimize differences between the two or more images to estimate a projective transformation between the two or more images to identify a current position of the cursor; accumulating, by the mobile handheld device, inertial information comprising accumulated motion of the mobile handheld device; the remote computing device utilizing the optical information, the inertial information, or a combination thereof to modify a position of the cursor from the current position to a different position with respect to the presentation, the utilizing further comprising: determining whether the optical information is sufficient to reliably determine a new position for the cursor; responsive to determining that the optical information is sufficient, evaluating only the optical information to determine the new position; responsive to the determining that the optical information is not sufficient, evaluating the inertial information to estimate the new position by accumulating angular accelerations from a previous image of the two or more images to estimate a rotation angle to a current image of the two or more images; and determining the new position by a product of the rotation angle and a resolution of the current image divided by an angle of the camera.