gen_kutter_sig(1)

NAME
gen_kutter_sig - a program to generate a signature for the wm_kutter_e watermarking program

SYNOPSIS
gen_kutter_sig [ -h ] [ -n number ] [ -o file ] [ -p number ] [ -q number ] [ -r number ]
[ -s number ] [ file ]

DESCRIPTION
gen_kutter_sig is a program to generate a signature to be embedded with the wm_kutter_e watermarking program and extracted with the wm_kutter_d program. The cmp_kutter_sig program is used to compare and test an extracted signature with the original signature.

Please refer to M. Kutter's paper "Digital Signature of Color Images using Amplitude Modulation", 1997, to get an idea about the algorithm.

OPTIONS

-h  Print a help message.

-n number
    Limit the signature length to number bits (0 < number <= 1024) unless reading from standard input. When reading from standard input, the signature is terminated by the first carriage return character.

-o file
    Output signature to the specified

-p number
    Density parameter in the range 0.0 < number <= 1.0. Default value 0.01.

-q number
    Signature strength. Default value 0.1.

-r number
    Signature bit repetition factor. Specifies how often a single signature bit is embedded. Default value 8. file instead of standard output.

-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.

file
    Input file to read raw signature data from. Default: standard input.

OUTPUT
The output file has the following format:

KTSG
    Magic to identify file type.

number
    The length of the signature in bits.

number
    The density parameter.

number
    The signature strength.

number
    The bit repetition parameter.

number
    The seed value for the pseudo-random number generator.

string
    The actual signature bytes.

AUTHOR
Peter Meerwald. Email bug reports to pmeerw@cosy.sbg.ac.at.

AVAILABILITY
The most recent released version of 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.

SEE ALSO
wm_kutter_e (1), wm_kutter_d (1), cmp_kutter_sig (1)