title: Digital watermarking robust to geometric distortions.
abstract: In this paper, we present two watermarking approaches that are robust to geometric distortions. The first approach is based on image normalization, in which both watermark embedding and extraction are carried out with respect to an image normalized to meet a set of predefined moment criteria. We propose a new normalization procedure, which is invariant to affine transform attacks. The resulting watermarking scheme is suitable for public watermarking applications, where the original image is not available for watermark extraction. The second approach is based on a watermark resynchronization scheme aimed to alleviate the effects of random bending attacks. In this scheme, a deformable mesh is used to correct the distortion caused by the attack. The watermark is then extracted from the corrected image. In contrast to the first scheme, the latter is suitable for private watermarking applications, where the original image is necessary for watermark detection. In both schemes, we employ a direct-sequence code division multiple access approach to embed a multibit watermark in the discrete cosine transform domain of the image. Numerical experiments demonstrate that the proposed watermarking schemes are robust to a wide range of geometric attacks.
authors.affiliation: Department of Electrical and Computer ENgineering, Illinois Institute of Technology, Chicago, IL 60616, USA.
authors.forename: Ping
authors.initials: P
authors.lastname: Dong
authors.forename: Jovan G
authors.initials: JG
authors.lastname: Brankov
authors.forename: Nikolas P
authors.initials: NP
authors.lastname: Galatsanos
authors.forename: Yongyi
authors.initials: Y
authors.lastname: Yang
authors.forename: Franck
authors.initials: F
authors.lastname: Davoine
mesh_terms: D000465:Algorithms; D016477:Artifacts; D003196:Computer Graphics; D016494:Computer Security; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D016247:Information Storage and Retrieval / Q000379:methods; D010363:Pattern Recognition, Automated / Q000379:methods*; D011356:Product Labeling / Q000379:methods*; D012815:Signal Processing, Computer-Assisted