Patent ID: 8818041
Filing Date: 2014-08-26
Classification: G06K,G06T

Abstract:
1. Method of controlling a function of a device, including: receiving a sequence of digital images taken at successive points in time using a camera; selecting at least one measurement zone including a plurality of image points; for at least one measurement zone, obtaining a signal representative of at least variations in a time-varying value of a combination of pixel values at at least a number of the image points, and determining at least one characteristic of the signal within at least a range of interest of its spectrum relative to comparison data, the determination comprising at least one of (i) determining whether the signal has a spectrum with a local maximum at a frequency matching a comparison frequency to a certain accuracy and (ii) determining whether at least a certain frequency component of the signal is in phase with a comparison signal to a certain accuracy; and controlling the function in dependence on the determination, wherein the method is unobtrusive to a living being present in a field of view of the camera, and wherein the living being can be in motion.