S> (Coined in a 1963 paper by Bogert, Healey, and Tukey) The Fourier tranSform of the log-magnitude Spectrum: fFt(ln( | fFt(window . Signal) | )) ThiS function iS uSed in Speech recognition and poSSibly elSewhere. Note that the outer tranSform iS NOT an inverSe Fourier tranSform (aS reported in many reSpectable DSP textS). [What' S it for?] (1997-01-07)