[PD] vowels

Bryan Jurish moocow at ling.uni-potsdam.de
Wed Sep 15 20:44:11 CEST 2004

moin Thomas, moin List,

tweaking the vowels is easy (ha!) -- actually recognizing them is
the tricky part, IM(ns)HO ... far as i know, the usual hack for
getting a phonetic transcription out of speech signal input is
a Hidden Markov Model (see Rabiner's tutorial for that).
If you know what's coming (pre-recorded samples), you can
get a vowel shift effect by tweaking the parameters of a
filter-bank -- keyword "vocoder".

<plug type="shameless">
since we're talking about HMMs, here's a new related link to my
current project:


this stuff is all very much work in progress, but it aims to
be an abstract C library (with the corresponding Pd bindings)
for finite-state machine operations (HMMs can be represented
as weighted finite-state transducers, and gfsm supports those),
similar in functionality to the absurdly expensive commercial
doodad from at&t.  In fact, the at&t folks use their library
for speech recognition, synthesis, and virtually every known
step in between, if you believe their publications...

more details in Graz ;-)


On 15 September 2004 at 19:18:07, Thomas Comiotto appears to have written:
 > Hi all,
 > I'm thinking of building a patch suitable for replacing specific vovels 
 > of some pre-recorded / live-captured speech fragments by some other 
 > vovels (eg. every 'uuh' becomes an 'ööh' or 'aah' or the like, while 
 > every 'iih stays an 'iih') for morphing/bending swiss-german idioms.  So 
 > I wanted to ask for possible solutions to do that in pd, possibly in 
 > realtime? I can think of analizing the source signal's FFT, modulate 
 > target vovels and feed results back into the resulting stream. But I'm 
 > quite an FFT newbie and perhaps there's a better/simpler approach?
 > Best regards
 > Thomas
 > _______________________________________________
 > PD-list at iem.at mailing list
 > UNSUBSCRIBE and account-management -> http://iem.at/cgi-bin/mailman/listinfo/pd-list

More information about the Pd-list mailing list