stegotools by Eduardo Sztokbant <du@du.eti.br>
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0. README HISTORY
1. LATEST RELEASE
2. BUILD
3. TEST
4. USE
4.1 stegwrite
4.2 stegread
5. LICENSE
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0. README HISTORY
revision 3 - 2005-07-06
Added information about the possibility of n_last_bits being 4.
revision 2 - 2005-07-05
Added information for number of last bits.
revision 1 - 2005-06-16
Documentation is like sex: when it is good, it is very, very good; and
when it is bad, it is better than nothing.
-- Dick Brandon
1. LATEST RELEASE
http://sourceforge.net/projects/stegotools/
2. BUILD
Issue the command "make" from the directory containing the Makefile and
both stegread and stegwrite will be built.
3. TEST
After building them it's a good idea to run the suite of tests I myself
prepared to verify if the binaries are working well. Just run "make test"
for it.
4. USE
4.1 stegwrite
stegwrite as you could guess is the writing program. It receives
information from the standard input, a reference to an existing BMP
file and a name for your desired output stego-BMP.
Example:
cat my_very_secret_file.txt | ./stegwrite my_girl.bmp stego-my_girl.bmp 1
This will hide the content of "my_very_secret_file.txt" into the file
"stego-my_girl.bmp", that will be virtually identical to "my_girl.bmp".
The last parameter passed to stegwrite ("1") is the number of last
bits of my_girl.bmp that will be used to hide your data. This value
can only be 1, 2 or 4. Note that the more bits you assign, more data
you can hide. However, you will lose more image details.
In case there is not enough space in my_girl.bmp to hide all the content
of "my_very_secret_file.txt" the information will be truncated. This means
not all of its content will be saved into "stego-my_girl.bmp". Don't worry,
stegwrite will warn you.
4.2 stegread
stegread does exactly the opposite of stegwrite: it reads hidden
information from a stego-BMP file and writes it in the standard output.
It's a good idea to redirect this output to another file using the
shell operator ">".
Example:
./stegread stego-my_girl.bmp 1 > my_very_secret_file-recovered.txt
This will read the information hidden in "stego-my_girl.bmp" and save it
into "my_very_secret_file-recovered.txt". Easy, huh?
The last parameter passed to stegread ("1") is the number of last bits
of stego-my_girl.bmp that were used to hide data. This value can only
be 1, 2 or 4.
Well, I think this is enough. You should make your own experiments now ;)
5. LICENSE
stegotools is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
stegotools is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with stegotools; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
For more details, see the file COPYING.