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ME_SGRAM(1-ESPS)                            ENTROPIC RESEARCH LAB



NNNNAAAAMMMMEEEE
     me_sgram - produces a  maximum-entropy-based  FEA_SPEC  file
     suitable for displaying as a spectrogram

SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
     mmmmeeee____ssssggggrrrraaaammmm [ ----ssss _r_a_n_g_e ] [ ----PPPP _p_a_r_a_m__f_i_l_e ] [ ----pppp _r_a_n_g_e ] [   ---- rrrr
     _r_a_n_g_e ] [ ----mmmm _m_e_t_h_o_d ] [ ----aaaa _l_p_c__m_e_t_h_o_d ] [ ----wwww _w_i_n_d_o_w__l_e_n ] [
     ----EEEE _p_r_e__e_m_p_h_a_s_i_s ] [ ----oooo _a_n_a_l_y_s_i_s__o_r_d_e_r ] [ ----SSSS _s_t_e_p__s_i_z_e ] [ ----
     dddd  _d_a_t_a__w_i_n_d_o_w  ]  [  ----cccc _c_o_n_v__t_e_s_t ] [ ----iiii _m_a_x__i_t_e_r ] [ ----DDDD ]
     _i_n_p_u_t._S_D _o_u_t_p_u_t._S_P_E_C

DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
     _M_e__s_g_r_a_m reads an ESPS sampled data file, pre-emphasizes it,
     and  produces  an ESPS FEA_SPEC(5-ESPS) file, which qresults
     from maximum entropy spectral analysis.  This file is  suit-
     able for displaying as a speech spectrogram.  (See _p_l_o_t_s_g_r_a_m
     (1-ESPS).)  By default (specifying no options) or by  speci-
     fying  _w_b  for  the  ----mmmm option, _m_e__s_g_r_a_m produces a FEA_SPEC
     file that simulates the analysis done to produce a wide-band
     speech spectrogram.  Alternatively, by specifying _n_b for the
     ----mmmm option, a FEA_SPEC file that simulates the analysis for a
     narrow-band  spectrogram  is computed.  The ----mmmm option simply
     defines different defaults for the other options.  By speci-
     fying  any  of  the  other  options,  in addition to ----mmmm, the
     default  values  are  overridden  by  the  specified  option
     values.   This allows the user to alter the basic display to
     highlight facets of the spectrogram that are  of  particular
     interest.

     _m_e__s_g_r_a_m is a shell script that makes  use  of  _f_i_l_t_e_r  (1 -
     ESPS),  _r_e_f_c_o_f (1-ESPS), and _m_e__s_p_e_c (1-ESPS); the parameter
     file is processed using _g_e_t_p_a_r_a_m (1-ESPS).

     If "-" is specified for the output file, standard output  is
     used.  Note, standard input cannot be read by this script.

OOOOPPPPTTTTIIIIOOOONNNNSSSS
     ----ssss _s_t_a_r_t__t_i_m_e:_e_n_d__t_i_m_e [0.0:(end of file)]

     ----ssss _s_t_a_r_t__t_i_m_e:+_d_u_r_a_t_i_o_n
          Determines the range in seconds in the input file  over
          which  the  spectrogram  values are to be computed.  In
          the first form, a pair of real numbers gives the start-
          ing  and ending times of the range.  The correspondence
          between samples and times is determined by two  quanti-
          ties:   the  starting time of the file and the interval
          between samples.  The former is given  by  the  generic
          header item _s_t_a_r_t__t_i_m_e in the input file, or 0.0 if the
          header item is not present.  The latter is the recipro-
          cal  of  the  sample frequency _s_f in the type-dependent
          part of the SD header.  If _s_t_a_r_t__t_i_m_e is  omitted,  the
          starting  time  of  the  file  is used.  If _e_n_d__t_i_m_e is



        Copyright Entropic Research Laboratory, Inc. 1G1        1






ME_SGRAM(1-ESPS)                            ENTROPIC RESEARCH LAB



          omitted, the range extends through the end of the file.
          The  second  form  of  the  option is equivalent to the
          first with _e_n_d = _s_t_a_r_t + _d_u_r_a_t_i_o_n .

     ----pppp _s_t_a_r_t_i_n_g__p_o_i_n_t:_e_n_d__p_o_i_n_t [1:(end of file)]

     ----pppp _s_t_a_r_t_i_n_g__p_o_i_n_t:+_i_n_c_r
          Determines the range in points in the input  file  over
          which  the  spectrogram  values are to be computed.  In
          the first form, a pair of unsigned integers  gives  the
          first and last points of the range, counting from 1 for
          the first point in the file.  If first is omitted, 1 is
          used.  If last is omitted, the range extends to the end
          of the file.  The second  form  is  equivalent  to  the
          first with last = first + incr . This option should not
          be specified if -s is specified.

     ----rrrr _r_a_n_g_e
          ----rrrr is a synonym for ----pppp.

     ----mmmm _m_e_t_h_o_d [wb]
          The basic method is specified here. There are two  pos-
          sible values:  _w_b for wide band and _n_b for narrow band.
          By  specifying  _w_b,  the  following  values  are   set:
          lpc_method  = fburg, pre-emphasis = .94, analysis_order
          = 10, window_len = 8 msec., step_size =  2  msec.,  and
          data_window  =  RECT.   By specifying _n_b, the following
          values are set: lpc_method = fburg, pre-emphasis = .94,
          analysis_order = 10, window_len = 40 msec., step_size =
          2 msec., and data_window = RECT.

     ----aaaa _l_p_c__m_e_t_h_o_d [fburg]
          Specifies the spectrum analysis method.  The default is
          the  fast  modified Burg ("fburg") method.  Also avail-
          able are the autocorrelation method  "autoc"),  covari-
          ance  method  ("cov"),  Burg  method ("burg"), modified
          Burg method ("mburg"), stuctured  covariance  ("strcov"
          and "strcov1"), and vector Burg ("vburg", fast approxi-
          mation to structured covariance.  Of the two structured
          covariance methods, the first ("strcov" is considerably
          faster and  better  behaved;  "strcov1"  is  older  but
          included  as  it  may  prove useful on occasion.  ** If
          "strcov"  is  used,  the  ----cccc  and  ----iiii  options   become
          relevant.   The  ----mmmm option overrides the value that may
          be in the parameter file.

     ----cccc _c_o_n_v__t_e_s_t[1e-5]
          Specifies, for the STRCOV method  only  (not  including
          STRCOV1),  a  convergence  test  value.   The lower the
          value, the smaller the change required on  each  itera-
          tion  before  the  estimator  terminates,  and the more
          iterations that normally will result.



        Copyright Entropic Research Laboratory, Inc. 2G2        2






ME_SGRAM(1-ESPS)                            ENTROPIC RESEARCH LAB



     ----iiii _m_a_x__i_t_e_r[20]
          Specifies, for the STRCOV method  only  (not  including
          STRCOV1),  the  maximum  number  of iterations that the
          estimator will run through before terminating.  A warn-
          ing  will  indicate if the estimator terminates because
          max_iter has been exceeded.

     ----wwww _w_i_n_d_o_w__l_e_n
          The duration of data in milliseconds over which the the
          power spectrum is computed for each column of the spec-
          trogram. The analysis bandwidth  is  inversely  propor-
          tional to this value.

     ----EEEE _p_r_e__e_m_p_h_a_s_i_s
          The coefficient _A in the pre-emphasis filter: 1 -  _A/z.
          This  filter is applied to the sampled data before com-
          puting the power spectrum. A value of _A = 1 provides  a
          6 dB/octave boost to the high frequencies; a value of 0
          provides no boost.

     ----oooo _a_n_a_l_y_s_i_s__o_r_d_e_r
          The number of parameters in  the  autoregressive  model
          that is used to compute the power spectrum.

     ----SSSS _s_t_e_p__s_i_z_e
          The time step in milliseconds between  columns  in  the
          spectrogram.   The  time resolution and horizontal mag-
          nification are affected by this parameter.

     ----dddd _d_a_t_a__w_i_n_d_o_w
          The data window applied to the data before the computa-
          tion  of the power spectrogram. Possible values include
          RECT (rectangular), HAMMING, and  TRIANG  (triangular).
          See  _w_i_n_d_o_w  (3 -ESPS) for a complete list of supported
          data windows.

     ----DDDD    Include in the output records  a  field  _d_i_t_h__s_p_e_c__v_a_l
          containing  1s  and  0s intended for display as a simu-
          lated gray-scale spectrogram on a black-and-white moni-
          tor.   The  _r_e_f_c_o_f (1-ESPS) output is piped through the
          _d_i_t_h_e_r(1-ESPS) program.

EEEESSSSPPPPSSSS PPPPAAAARRRRAAAAMMMMEEEETTTTEEEERRRRSSSS
     The parameter file is not required to be present,  as  there
     are  default  parameter values that apply.  If the parameter
     file does exist, the following parameters are read:

     _m_e_t_h_o_d - _s_t_r_i_n_g
          The spectrogram method to use.  This parameter  is  not
          read  if  the  ----mmmm  option is used.  If the parameter is
          present and is read, it determines default  values  for
          all  other parameters as discussed under the ----mmmm option.



        Copyright Entropic Research Laboratory, Inc. 3G3        3