------------------
StirMark Benchmark
------------------

If you wish to reproduce the results presented on:

   <http://www.cl.cam.ac.uk/~fapp2/watermarking/benchmark/>

use the following procedure:

- Original images: lena, bear, skyline arch, watch, baboon and fishing
  boat. These can be downloaded from:

   <http://www.cl.cam.ac.uk/~fapp2/watermarking/benchmark/
   image_database.html>

- Watermark these the images with your software. This can be done by
  modifying the Watermark.bat batch file in this directory. Until
  their PSNR is greater than 38dB. To measure the PSNR, you can modify
  the PSNR.bat batch provided in this directory.

  PSNR is obviously not the best quality metric because it does not
  take into account the properties of the human vision system. Future
  version of StirMark shall include better metrics. [Any suggestion?]

  If your system permits it, embed on of the following random strings:
  ``gr42nRw:'' if your systems use error correction codes;
  ``gr42nRw:t'' if it does not.

- Attack each watermarked image `attack' with the predefined set of
  transformations implemented into StirMark:
  stirmark -Timage my_image.ppm
  For this purpose you can modify the Attack.bat batch included in
  this package.

- Try to extract the watermark (modify the Detect.bat batch). If your
  system only says that there is or not a watermark simply count all
  the ``there is a watermark'' answers as 1 and all the others as
  0. If you embedded the random string proposed earlier and your system
  does not include correction code count 1 if 64 of the bits are
  recovered correctly and 0 otherwise. If your system does include
  error correction code count 1 whenever all the bits are recovered.


The batch files in this directory are mainly intended for Windows NT
users. They assume the following location of files:

/ --+- stirmark.exe
    |
    +- watermark.exe     your watermarking software
    |
    +- watermark.bat
    |
    +- psnr.bat
    |
    +- attack.bat
    |
    +- detect.bat
    |
    +- Attacked/
    |
    +- Watermarked/
    |
    +- Samples/ --+- baboon.ppm
                  |
                  +- bear.ppm
                  |
                  +- lena.ppm
                  |
                  +- skyline_arch.ppm
                  |
                  +- watch.ppm
                  |
                  +- fishing_boat.pgm


$Header: /StirMark/Test/Benchmark.txt 3     7/04/99 11:49 Fapp2 $