Newsgroups: comp.speech
Path: pavo.csi.cam.ac.uk!doc.ic.ac.uk!agate!ames!riacs!danforth
From: danforth@riacs.edu (Douglas G. Danforth)
Subject: Re: Very simple speech recognition Alg. wanted.
Message-ID: <1992Nov12.232526.17013@riacs.edu>
Sender: news@riacs.edu
Organization: RIACS, NASA Ames Research Center
References: <MHALL.92Nov9152432@occs.cs.oberlin.edu> <1992Nov12.180625.13886@riacs.edu>
Distribution: comp.speech
Date: Thu, 12 Nov 92 23:25:26 GMT
Lines: 15


Addendum to QUICKY:

Amplitude normalization: 
  Forgot to mention that the amplitude in each segment should be normalized
otherwise loud sounds will look different from  soft sounds even though
the same word is spoken.  The Interstate Algorithm actually just
uses the amplitude difference (1 bit) from one lowpass filter to the
next higher frequency within a segment.  For 16 filters there are
15 differences.  An increase gets a 1 bit.  No change or decrease gets
a 0 bit.  The result is a 256 bit (pad low frequency with zeros) pattern.
You can try other schemes as well.

Doug Danforth

