Weakness of existing watermarking schemes
[Up] StirMark 3.1

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     Prepare yourself for the next generation of StirMark!

     Broad claims have been made about the "robustness" of various digital
     watermarking method. Unfortunately the criteria as well as the pictures
     used to demonstrate these claims vary from one system to the other and
     recent attacks show that the robustness criteria used until now are
     inadequate: JPEG compression, additive Gaussian noise, low pass
     filtering rescaling and cropping have been addressed in most the
     literature but specific distortions such as rotation have been rarely
     addressed. In some cases the watermark is simply said to be "robust
     against common signal processing algorithms and geometric distortions
     when used on some standard images".

     Most of the potential attacks detailed in "A Fair Benchmark for Image
     Watermarking Systems" are actually implemented into this version of
     StirMark: given a watermarked image, StirMark will apply these
     transformations with various parameters. Then the output images can be
     tested with watermark detection or extraction programs. The full
     process can be automated using a simple batch file.

     Using StirMark for any other purpose than research or evaluation of
     copyright marking systems is prohibited, at least in Europe: "Member
     States shall provide adequate legal protection against the
     circumvention without authority of any effective technological measures
     designed to protect any copyrights or any rights related to copyright
     as provided by law or the sui generis right provided for in chapter III
     of European Parliament and Council Directive 96/9/EC".

     If you use StirMark for your research, please cite:

          Fabien A. P. Petitcolas, Ross J. Anderson, Markus G. Kuhn.
          Attacks on copyright marking systems, in David Aucsmith (Ed),
          Information Hiding, Second International Workshop, IH'98,
          Portland, Oregon, U.S.A., April 15-17, 1998, Proceedings,
          LNCS 1525, Springer-Verlag, ISBN 3-540-65386-4, pp. 219-239.

     and

          Fabien A. P. Petitcolas and Ross J. Anderson, Evaluation of
          copyright marking systems. In proceedings of IEEE Multimedia
          Systems (ICMCS'99), vol. 1, pp. 574--579, 7--11 June 1999,
          Florence, Italy.

     [*] Download & usage
          [-] StirMark 3.1 (79) is freely available in full portable ISO C
          source code. Users should read the "Copyright" file provided in
          the package for copyright information about code and libraries
          used in StirMark. [updated 7 April 1999].
          [-] The Readme file contains all necessary information to use
          StirMark.
          [-] StirMark 1.0 is still available from Markus G. Kuhn's homepage
          and a Macintosh version has been sent to us and is provided "AS
          IS".

     [*] Samples
          [-] Result sheet [MS Excel] of the StirMark Benchmark
          [-] See what's going on when you apply StirMark
          [-] Some attack examples
          [-] StirMark on video: if you apply StirMark to each frame of a
          video sequence very annoying effects will appear when the sequence
          is played (see example below). The reason is that StirMark has not
          been designed to attack video sequences but still images: by
          default the distortions are different for each picture. If you
          want to attack video sequences, make sure you save the distortion
          parameters applied to the first frame and apply them to the other
          frames. You can use the -PS/-PL options for this purpose. (See
          README file)
                                              [North west video (watermarked)]
                                                        Marked video
           [North west video (StirMarked)] [North west video (StirMarked SL)] [North west video (StirMarked S+L+)]
                 Default parameters               Using -PS/-PL options              Using -PS+/-PL+ options
           If you wish to apply StirMark to video, make sure you use the same distortion parameters for each
           sequence (-PS/-PL options). By default, distortions are indeed random and are different for each frame
           so this produces very annoying effects when the sequence is played. Courtesy of Jana Dittmann and Thomas
           Fiebig, German National Research Center for Information Technology, Darmstadt, Germany.

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Copyright © 1997-2000 by Fabien A. P. Petitcolas, Computer Laboratory,
University of Cambridge