Synchronized detection of the block-based watermark with invisible grid embedding

Po-Chyi Su; C.-C. Jay Kuo

doi:10.1117/12.435424

1 August 2001 Synchronized detection of the block-based watermark with invisible grid embedding

Po-Chyi Su, C.-C. Jay Kuo

Proceedings Volume 4314, Security and Watermarking of Multimedia Contents III; (2001) https://doi.org/10.1117/12.435424
Event: Photonics West 2001 - Electronic Imaging, 2001, San Jose, CA, United States

Abstract

The loss of synchronization caused by geometrical modifications of an image, such as cropping, rotation and scaling, increases the difficulty of watermark detection, especially for block-based watermarking schemes. In this research, we consider an algorithm to embed an invisible grid structure into watermarked images to overcome this problem. A fixed-size 2D pseudo-random pattern is repeatedly embedded along horizontal and vertical directions of an image after the watermark is embedded in the image. In watermark detection, the affine matrix as well as horizontal/vertical shifts associated with certain geometrical attacks are determined by calculating the auto- correlation of the extracted grid structure and the cross- correlation between the folded grid and the embedded pattern. Synchronization is then recovered, and the watermark can be more easily detected. The applicability and advantages of the proposed algorithm are demonstrated by experimental results.

Citation Download Citation

Po-Chyi Su and C.-C. Jay Kuo "Synchronized detection of the block-based watermark with invisible grid embedding", Proc. SPIE 4314, Security and Watermarking of Multimedia Contents III, (1 August 2001); https://doi.org/10.1117/12.435424

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