.TH FILTER 1carl CARL
.SH NAME
filter \- program for performing FIR or IIR digital filtering 
.SH SYNOPSIS
.B filter
filter_file < floatsams > floatsams
.SH DESCRIPTION
The 
.B filter 
program is for FIR and IIR digital filtering.
You provide a filterfile such as designed by \fIfir\fR or \fIlpc\fR,
and an input signal.  The input and output data streams must be floatsams
(binary, floating-point sample values).  This program will work with
any legal filter, but it is best used on IIR filters and on FIR filters
with short (e.g., less than 20 samples) impulse responses.  For long
FIR filters, the 
.B fastflt
filtering program is more efficient.
.LP
Note: the gain of the filter will depend on the specified filter_file.
If this file is not normalized to unity gain (e.g., filters produced by
\fIlpc\fR ), then an additional gain stage may be required to keep the
peak value under 1.0.
.SH AUTHOR
Mark Dolson
.SH SEE ALSO
fir(1carl), lpc(1carl)
.SH BUGS
