US Patent 10136184 Methods and apparatus to detect people

Example apparatus disclosed herein include processor circuitry and memory including machine executable instructions which, when executed, cause the processor circuitry to generate a first presence indication based on a threshold number of portions of an image including a first human pulse waveform. The example instructions, when executed, also cause the processor circuitry to identify a first location associated with a face in the image based on thermal imaging data, and adjust a first count based on a comparison of the first location associated with the face and a second location associated with the first presence indication.