
darpsd(1)                    Khoros                     darpsd(1)

PROGRAM
     darpsd - 1D Autoregressive (AR) PSD

SYNTAX
     darpsd

     -i             input file (xviff file)

     -o             resulting output file (xviff file)

     [-n]           number of points for PSD estimate

     [-t]           AR coefficients from Lattice filter(1) or
                    TAPPED filter(0) (default)

     [-p]           Phase estimate(0) or PSD estimate(1)
                    (default)

     [-y]           do NOT normalize (0) or YES normalize(1)
                    (default)

     [-d]           down vectors(0) or across bands(1) (default)

     [-V]           Gives the version for darpsd

     [-U]           Gives the usage for darpsd

     [-P]           Prompts for command line options

     [-A [file1]]   Creates the answer file called darpsd.ans or
                    file1

     [-a [file1]]   Uses darpsd.ans or file1 as the answer file

DESCRIPTION
     darpsd 1D AR PSD/Phase Estimation.  Determines the 1D
     autoregressive (AR) PSD and Phase spectral estimate of the
     input file.  The input file consists of autoregressive
     parameters.  The autoregressive parameters can originate
     either on a tapped-delay or lattice filter realizations.
     The user is allowed to extrapolate the PSD or Phase estimate
     to the desired number of points.  It can operate on Real and
     Complex data.

     NOTE 1: complex data is expected to be in rectangular (not
     polar) form.

     NOTE 2: if input data is real the Phase spectra will be 0.0.

     For a more theoretical discussion of AR PSD estimation algo-
     rithms see:  Modern Spectral Estimation: Theory and Applica-
     tion, by Steven M. Kay, Prentice Hall, 1988.

     darpsd does not work on explicit location data and will
     return an error when such a file is encountered.  No output
     file will be created.  darpsd works only on VFF_TYP_FLOAT or
     VFF_TYP_COMPLEX data files.

     Input/Output Files
     The input file must be of type VFF_TYP_FLOAT or
     VFF_TYP_COMPLEX.  The output file returned will be of size
     specified by the user.  If the data is of type
     VFF_TYP_COMPLEX and complex aithmetic is selected then the
     output file will be of type VFF_TYP_FLOAT.
     *********************************************************************

     Process direction
     Data can be processed with either band or vector orientation
     (-d option).  The default data processing direction is in
     the vector direction (-d = 0).  pixel location.  The direc-
     tion of processing can be changed so that each band is pro-
     cessed as a signal (instead of each vector being a signal)
     by setting the -d option to 1.

REQUIRED ARGUMENTS
     -i     type: infile
            desc: input file (xviff file)

     -o     type: outfile
            desc: resulting output file (xviff file)

OPTIONAL ARGUMENTS
     -n     type: integer
            desc: number of points for PSD estimate
            default: 1
            bounds: value > 0

     -t     type: boolean
            desc: AR coefficients from Lattice filter(1) or
            TAPPED filter(0) (default)
            default: false

     -p     type: boolean
            desc: Phase estimate(0) or PSD estimate(1) (default)
            default: true

     -y     type: boolean
            desc: do NOT normalize (0) or YES normalize(1)
            (default)
            default: true

     -d     type: boolean
            desc: down vectors(0) or across bands(1) (default)
            default: true

EXAMPLES
SEE ALSO
     intro(1), verror(3), vgparms(3), vutils(3), ldarpsd(3)

RESTRICTIONS
     works only on VFF_TYP_COMPLEX and VFF_TYP_FLOAT.

     darpsd does not work on explicit location data and will
     return an error when such a data file is encountered.

COPYRIGHT
     Copyright 1992, University of New Mexico.  All rights
     reserved.

Khoros                    Release: 1.0                          1

