PROCESS UDECON  (USER DEFINED DECONVOLUTION)

Document Date: 26 February 1988

UDECON calculates and applies a Wiener deconvolution filter given a 
series of input and desired output values or the cross-correlation and 
auto-correlation functions.  The output appears in the "standard output"
(print file) and may be the input, output, cross-correlation, auto-
correlation, the Wiener filter coefficients, the Wiener-Levinson error,
the deconvolved input, or the rms error of the deconvolved and input
series.

No standard SIOSEIS input or output is available.  All input and output
is within this process.  i.e. the procs list should be PROCS UDECON END

Each parameter list must be terminated with the word END.  The entire set
of udecon parameters must be terminated by the word END.

THE PARAMETER DICTIONARY
--- --------- ----------

INPUT  - A list of input values representing a seismic trace.  The input
         will be correlated with itself and with the desired output.

DESIRE - A list of desired output values representing the desired output trace.

AUTO   - A list of auto-correlation values that will be used instead of
         the input and desired output.

CROSS  - A list of cross-correlation values.

OPRINT - A bit switch indicating the printer output.  Bit x is 2**x.
       bit 0,  The cross-correlation is printed.
       bit 1,  The auto-correlation is printed.
       bit 2,  The prediction filter is printed.
       bit 3,  The Wiener-Levinson error is printed.
       bit 4,  The deconvolved input is printed.
       bit 5,  The RMS error between the deconvolved input and the inputs printed.
         Preset = 0     e.g. oprint 32    sets bit 5 only
                             oprint 96    sets bits 5 and 6
                             oprint 127   sets all bits

NFPTS  - The number of filter points to use.  NFPTS must be larger than
         the period to be removed.  NFPTS is also the number of lags in
         the correlations.  If NFPTS is omitted when the autocorrelation
         is given, NFPTS is set to the number of points in the auto-
         correlation.

PREWHI - The percentage prewhitening to add before filter design.  A
         high level of prewhitening reduces the effectiveness of the 
         filter.  Some level of prewhitening is needed in order for the
         filter to be stable.  Prewhitening is like performing a bandpass
         filter before decon. 
         Preset=25.

END    - Terminates each parameter list.


Written and copyrighted (c) by:
Paul Henkart, Scripps Institution of Oceanography, August 1986 
ALL RIGHTS RESERVED