


VU(1)                    USER COMMANDS                      VU(1)



NAME
     vu :- Voiced/Unvoiced information generator

SYNOPSIS
     vu (-I) (-i item) (-TE n) (-TR n) (TP n) (-TB n) (-TF n)  (-
     R) file

DESCRIPTION
     vu is a program which generates a "VU_TYPE"  item  from  the
     speech  waveform.   A voiced/unvoiced value, between 0 and 1
     is output, these representing respectively, total  devoicing
     and  perfect  voicing.   If an optional tx item is chosen, a
     voiced/unvoiced value is output at each tx marker. When  the
     tx  markers  are  spaced  at more than 20ms apart a value is
     output at every 10ms. If a tx type is  not  to  be  used,  a
     voiced/unvoiced  value  is output every 10ms.  Three parame-
     ters are employed for the voiced/unvoiced decision. This  is
     the  speech  energy, the first ACF value and the height of a
     peak in the  correlation  function  of  a  clipped-low-pass-
     filtered version of the speech.

     Alternativly the tx markers alone may  be  used  to  make  a
     voiced/unvoiced  decision.  If these are spaced at more than
     20ms, the speech is deemed unvoiced. This option is  invoked
     by   -R.   Input  options  for  thresholds  for  making  the
     voiced/unvoiced decisions are as follows:

     -TEnn      A floating point number giving the ratio of  glo-
                bal  signal  energy to block signal energy, above
                which block should be deemed silence. Default=20.

     -TRnn      A floating  point  number  giving  threshold  for
                first  auto-correlation  value to be used in con-
                juction with peak approx 1 pitch periods position
                in ACF. Default=0.7.

     -TPnn      A floating point number  threshold  for  peak  in
                low-pass-filtered  decimated  and  centre clipped
                speech. When this peak is  less  than  this  (TP)
                threshold  and  first  ACF is less than TR thres-
                hold, block is deemed unvoiced. Default=0.6.

     -TFnn      A floating point number giving value of first ACF
                below  which block is deemed unvoiced regardless.
                Default=0.4.

     -TBnn      A floating point number giving value of  peak  in
                ACF  below which block is deemed unvoiced regard-
                less.  Default=0.4.

INPUT ITEMS
     1.xx       Any speech item



SFS                     Last change: GEC                        1






VU(1)                    USER COMMANDS                      VU(1)



     3.xx       Any tx item

OUTPUT ITEMS
     10.        VU_TYPE item.  The  'flag'  variable  contains  a
                binary  voicing  decision.  The single data value
                contains the first auto-correlation value.

VERSION/AUTHOR
     2.0        K Frimpong-Ansah

     3.0        Mark Huckvale

SOURCE
     /users/mark/sfs/man/../ucl/vu.c









































SFS                     Last change: GEC                        2



