1. A method for detecting cardiac arrhythmia from signals generated from video images captured of a subject of interest being monitored for cardiac function in a non-contact remote sensing environment, the method comprising: receiving a time-series signal generated from video images captured of a region of exposed skin where a photoplethysmographic (PPG) signal of a subject of interest can be registered, said video comprising video images captured by at least one imaging channel capturing PPG signals; processing said time-series signal to extract a PPG signal for said subject; filtering said PPG signal to obtain a filtered PPG signal, said filtering comprising: y ⁡ ( n ) = 1 N ⁢ ∑ 1 N ⁢ x ⁡ ( n - i ) where N is a number of frames in a moving window, x is said unfiltered PPG signal, n is a current frame and i is an index designating said moving window frame; detecting peak-to-peak pulse points in said filtered PPG signal; analyzing said pulse points to obtain peak-to-peak pulse dynamics; and determining whether a cardiac arrhythmia exists based on said pulse dynamics.