A gait waveform feature extracting method and an individual identification
system extract features of the gait waveform. A one-step waveform
corresponding to one step of a walking movement is specified using, as an
index, a peak amplitude corresponding to a state where substantially a
whole bottom surface of one foot is in contact with the ground and a toe
of the other foot is just after leaving the ground among the electric
field displacement formed on the human body in accordance with the human
body's walking movements. Based on the specified one-step waveform, the
features of the one-step waveform are extracted, so that the peak
amplitude appears without influence from electric-charge interference
between the right and left legs. Accordingly, the one-step waveform
reflects the actual one step of the walking movement, and therefore, the
features of the one-step waveform can be precisely extracted.