Raymond B. Wolfgang and Christine I. Podilchuk and Edward J. Delp

CERIAS TR 2007-41

inproceedings

The growth of new imaging technologies has created a need for techniques that can be used for copyright protection of digital images. Copyright protection involves the authentication of image content and/or ownership and can be used to identify illegal copies of a (possibly forged) image. One approach for copyright protection is to introduce an invisible signal known as a digital watermark in the image. In this paper, we describe digital image watermarking techniques, known as perceptually based watermarks, that are designed to exploit aspects of the human visual system. In the most general sense, any watermarking technique that attempts to incorporate an invisible mark into an image is perceptually based. However, in order to provide transparency (invisibility of the watermark) and robustness to attack, more sophisticated use of perceptual information in the watermarking process is required. Several techniques have been introduced that incorporate a simple visual model in the marking procedure. Such techniques usually take advantage of frequency selectivity and weighing to provide some perceptual criteria in the watermarking process. Even more elaborate visual models are used to develop schemes that not only take advantage of frequency characteristics but also adapt to the local image characteristics, providing extremely robust as well as transparent schemes. We present examples from each category - from the simple schemes that guarantee transparency to the more elaborate schemes that use visual models to provide robustness as well as transparency.

PDF

1999 – 01

Proceedings of the SPIE/IS&T International Conference on Security and Watermarking of Multimedia Contents

Wolfgang

40--51

School of Electrical and Computer Engineering

Purdue University and Bell Laboratories and Purdue University

2001-01-01