.\"
.\" gen_kutter_sig.1 - the *roff document processor man page source
.\"
.TH gen_kutter_sig 1 "98/06/30" "Watermarking, Version 1.0"
.SH NAME
.B gen_kutter_sig 
\- a program to generate a signature for
the 
.B wm_kutter_e 
watermarking program
.SH SYNOPSIS
.B gen_kutter_sig
[
.B \-h
]
[
.BI \-n \ number
]
[
.BI \-o \ file
]
[
.BI \-p \ number
]
[
.BI \-q \ number
]
[
.BI \-r \ number
]
.br
[
.BI \-s \ number
]
[
.I file
]
.SH DESCRIPTION
.B gen_kutter_sig
is a program to generate a signature to be
embedded with the 
.B wm_kutter_e 
watermarking program and extracted with the 
.B wm_kutter_d 
program. The
.B cmp_kutter_sig 
program is used to compare and test an
extracted signature with the original signature.
.PP
Please refer to M. Kutter's paper "Digital Signature of Color Images
using Amplitude Modulation", 1997, to get an idea about the algorithm.
.PP
.SH OPTIONS
.TP
.B \-h
Print a help message.
.TP
.BI \-n \ number
Limit the signature length to
.I number
bits (0 <
.I number
<= 1024) unless reading from standard input. When reading from
standard input, the signature is terminated by the first
carriage return character.
.TP
.BI \-o \ file
Output signature to the specified 
.TP
.BI \-p \ number
Density parameter in the range 0.0 <
.I number
<= 1.0. Default value 0.01.
.TP
.BI \-q \ number
Signature strength. Default value 0.1.
.TP
.BI \-r \ number
Signature bit repetition factor. Specifies how often a single
signature bit is embedded. Default value 8.
.I file
instead of standard output.
.TP
.BI \-s \ number
Specify a seed value to initialize the pseudo-random number 
generator; if not specified, time and pid (process id) are used
to initialize the pseudo-random number generator.
.TP
.I file
Input file to read raw signature data from. Default: standard
input.
.PP
.SH OUTPUT
The output file has the following format:
.TP
.B KTSG
Magic to identify file type.
.TP
.I number
The length of the signature in bits. 
.TP
.I number
The density parameter.
.TP 
.I number
The signature strength.
.TP
.I number
The bit repetition parameter.
.TP
.I number
The seed value for the pseudo-random number generator.
.TP
.I string
The actual signature bytes.
.PP
.SH AUTHOR
Peter Meerwald. Email bug reports to pmeerw@cosy.sbg.ac.at.
.SH AVAILABILITY
The most recent released version of
.B gen_kutter_sig
is always available
at http://www.cosy.sbg.ac.at/~pmeerw/Watermarking or via anonymous ftp from ftp.cosy.sbg.ac.at in the
directory /pub/people/pmeerw/Watermarking.
.SH "SEE ALSO"
.BR wm_kutter_e
(1),
.BR wm_kutter_d
(1),
.BR cmp_kutter_sig
(1)