Principle of strobe-point generation: The fundamental frequency estimate of a periodic signal is assumed to increase linearly from 50 Hz to 150 Hz in the time interval 0–100 ms (blue curve, left scale). The corresponding phase function according to (2) is normalized by 2π and taken modulo 1 (red curve, right scale). Whenever the phase wraps, a strobe point is set (indicated by black bars with circles on top). The time span between subsequent strobe points indicates the stabilized period.