attacks on copyright marking systems
TRANSCRIPT
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<http://www. cl .cam.ac. uk /~fapp2/papers/ih98-attacks/>
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skytale:SysCoP$ imageread_demo syscop_watermarked.ppmKey:
No certificate file.-------------------------------------------------A valid watermark found - estimated correction percentage is : 100Retrieved Secret Label (string) : SysCoP(TM)
skytale:SysCoP$ imageread_demo syscop_jitter.ppmKey:
No certificate file.-------------------------------------------------Cannon find valid watermark - failed.Image syscop_jitter.ppm has been tampered or hasnot been watermarked.
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