1. A system configured to identify lexical segments in speech, the computer system comprising: an input interface configured to receive an input of audio; an energy calculation module configured to calculate energy of said audio over first time intervals of said audio; a variance calculation module configured to calculate variance of the energy in the first time intervals of said audio over every second time interval within said first time intervals that slides as the energy calculation module calculates the energy of said audio at each of said first time intervals; a speech segmentation module configured to determine whether the variance of the energy of said audio over each second time interval is greater than a threshold value of variance of the energy of said audio, determine for said audio over each of said second time intervals that said audio over each of said second time intervals contains speech in response to determining that the variance of the energy of said audio over each second time interval is greater than the threshold value, and determine lexical segment boundaries of said speech within the audio based on each of said second time intervals fluid audio that contains speech, wherein the threshold value of variance of the energy of said audio is one standard deviation above a mean variance of energy of the audio signal.