Watermark capacity measure incorporating a model of the human visual system

Alessia De Rosa; Mauro Barni; Franco Bartolini; Alessandro Piva

doi:10.1117/12.435432

1 August 2001 Watermark capacity measure incorporating a model of the human visual system

Alessia De Rosa, Mauro Barni, Franco Bartolini, Alessandro Piva

Proceedings Volume 4314, Security and Watermarking of Multimedia Contents III; (2001) https://doi.org/10.1117/12.435432
Event: Photonics West 2001 - Electronic Imaging, 2001, San Jose, CA, United States

Abstract

The problem of evaluating the maximum number of information bits that can be hidden within an image is considered; usually it is addressed by looking at the watermarking process as a communication task, in which the signal, i.e. the watermark, is transmitted over the channel, the host data acts the part of. Thus the maximum number of information bits is the capacity of the watermark-channel. By relying on experimental results in which the dependence of the watermark capacity upon the watermark strength G is evidenced, the knowledge of the maximum allowed watermark level, under the constraint of watermark invisibility, is required. G is often interactively adjusted to the image at hand, because no simple algorithm exists that permits to fit the watermark level according to the characteristics of the host image. Hence, a novel algorithm to model the Human Visual System has been developed which considers frequency sensitivity, local luminance and contrast masking effects. The proposed method exploits a block based DCT decomposition of the image, that permits to trade off between spatial and frequency localisation of the image features and disturbs. Through this model, the maximum allowable watermark strength is determined in a completely automatic mode and then the value of watermark capacity is computed.

Citation Download Citation

Alessia De Rosa, Mauro Barni, Franco Bartolini, and Alessandro Piva "Watermark capacity measure incorporating a model of the human visual system", Proc. SPIE 4314, Security and Watermarking of Multimedia Contents III, (1 August 2001); https://doi.org/10.1117/12.435432

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available