GenNoise







GenNoise [options] AFile


Generate an audio file containing uncorrelated Gaussian
    noise samples

This program generates zero‐mean uncorrelated pseudo‐random
Gaussian deviates.  These white noise samples are written to
an audio file.  Each invocation of this program generates a
different random sequence.  Options are available to specify
the number of samples, the sampling frequency and the data
format of the output file.


Output file name: AFile:
    Specifying "‐" as the output file indicates that output
    is to be written to standard output.  If the output file
    type is not explicitly given (‐F option), the extension
    of the output file name is used to determine the file
    type.
      ".au"   ‐ AU audio file
      ".wav"  ‐ WAVE file
      ".aif"  ‐ AIFF‐C sound file
      ".raw"  ‐ Headerless file (native byte order)
      ".txt"  ‐ Headerless file (text data)
‐d SDEV, ‐‐std_deviation=SDEV
    Standard deviation of the noise samples, default 1000.
‐x SEED, ‐‐seed=SEED
    Seed for the random number generator, default from
    current time.
‐n NSAMPLE, ‐‐number_samples=NSAMPLE
    Number of output samples to be generated.
‐s SFREQ, ‐‐srate=SFREQ
    Sampling frequency for the output audio file, default
    8000.
‐F FTYPE, ‐‐file_type=FTYPE
    Output file type.  If this option is not specified, the
    file type is determined by the output file name
    extension.
      "AU" or "au"             ‐ AU audio file
      "WAVE" or "wave"         ‐ WAVE file
      "WAVE‐NOEX" or "wave‐noex" ‐ WAVE file (no extensible data)
      "AIFF‐C" "aiff‐c"        ‐ AIFF‐C sound file
      "AIFF" or "aiff"         ‐ AIFF sound file
      "noheader" or "noheader_native" ‐ Headerless file (native byte
                                 order)
      "noheader_swap"          ‐ Headerless file (byte swapped)
      "noheader_big‐endian"    ‐ Headerless file (big‐endian byte
                                 order)
      "noheader_little‐endian" ‐ Headerless file (little‐endian byte
                                 order)
‐D DFORMAT, ‐‐data_format=DFORMAT
    Data format for the output file, default integer16









                             ‐2‐


      "mu‐law8"   ‐ 8‐bit mu‐law data
      "A‐law8"    ‐ 8‐bit A‐law data
      "unsigned8" ‐ offset‐binary 8‐bit integer data
      "integer8"  ‐ two’s‐complement 8‐bit integer data
      "integer16" ‐ two’s‐complement 16‐bit integer data
      "integer24" ‐ two’s‐complement 24‐bit integer data
      "integer32" ‐ two’s‐complement 32‐bit integer data
      "float32"   ‐ 32‐bit floating‐point data
      "float64"   ‐ 64‐bit floating‐point data
      "text"      ‐ text data
    The data formats available depend on the output file
    type.  AU audio files:
      mu‐law, A‐law, 8/16/24/32‐bit integer, 32/64‐bit float
    WAVE files:
      mu‐law, A‐law, offset‐binary 8‐bit integer, 16/24/32‐bit integer,
      32/64‐bit float
    AIFF‐C sound files:
      mu‐law, A‐law, 8/16/24/32‐bit integer, 32/64‐bit float
    AIFF sound files:
      8/16/24/32‐bit integer
    Headerless files:
      all data formats
‐I INFO, ‐‐info=INFO
    Audio file information string for the output file.
‐h, ‐‐help
    Print a list of options and exit.
‐v, ‐‐version
    Print the version number and exit.

     By default, the output file contains a standard audio
file information string.
  Standard Audio File Information:
     date: 1994‐01‐25 19:19:39 UTC    date
     user: kabal@aldebaran            user
     program: GenNoise                program name
This information can be changed with the header information
string which is specified as one of the command line
options.  Structured information records should adhere to
the above format with a named field terminated by a colon,
followed by numeric data or text.  Comments can follow as
unstructured information.
  Record delimiter: Newline character or the two character escape
      sequence "\" + "n".
  Line delimiter: Within records, lines are delimiteded by a carriage
      control character, the two character escape sequence "\" + "r",
      or the two character sequence "\" + newline.
If the information string starts with a record delimiter,
the header information string is appended to the standard
header information.  If not, the user supplied header
information string appears alone.













                             ‐3‐


P. Kabal / v4r2  2003‐01‐27

AFsp