Patent ID: 8532197

Claim:
A method for detecting a temporally oscillating source in digital video signals, comprising: using an imaging device to capture a sequence of input images of a scene; generating digital video signals from the sequence of input images; and processing the digital video signals using a recursive Infinite Impulse Response (IIR) filter technique based on a differentiated version of Goertzel's Algorithm to detect a temporally oscillating source in the digital video signals; wherein the differentiated version of Goertzel's Algorithm is defined by the equation: W ⁡ ( z ) = 1 - z - 1 1 - 2 ⁢ ⁢ cos ⁡ ( 2 ⁢ π ⁢ f f s ) ⁢ z - 1 + z - 2 , where f is the frequency of interest, f s is the sampling frequency and z is the independent variable of the discrete laplace transform.