Abstract: A method for serialization of items, comprising encrypting a serial number of each item using an encryption key k to obtain unique serial numbers and marking the unique serial numbers on the items. The unique serial numbers having a length L are included into a string of symbols having a length L?, with L? larger than L, and marked on the items. A corresponding method for recovering a unique code and corresponding serial number from a string of symbols marked on an item, as well as corresponding serialization and recovering systems are disclosed.

Abstract: A method of digital watermarking which can resist against local geometrical distortions such as random bending attack, global geometrical distortions as well as projective transforms, but does not necessary require the recovering of global affine transform or even the repetition of the same watermark pattern. Further, the watermark can resist common global affine transformations such as rotation, scaling, and changes of aspect ratio, cropping as well as other types of operations such as filtering, lossy compression, printing/scanning or detection of watermark in front of video, web or photo camera or any imaging device.

Abstract: The present invention is a method and apparatus for watermarking text or vector graphics documents. It is based on character-wise or vector graphics element-wise grayscale or color modulation. At high resolution, halftone or dither modulation can also be used in addition or in place of grayscale/color modulation, for printed representation of electronic document. For the detection, the document is acquired through an acquisition device, document segmentation is performed, characters/elements are segmented, the watermark signal is estimated and the information is decoded. Although the proposed scheme mostly addresses the watermarking of hard-copy documents, it can easily be integrated into electronic document editing and acquisition tools, and the watermark is attached to the document electronic version. The invention is applicable either using expensive high-resolution printing and acquisition devices, either using common cheap low-resolution devices, depending on the application needs.

Abstract: The present invention is a method and apparatus for watermarking text or vector graphics documents. It is based on character-wise or vector graphics element-wise grayscale or color modulation. At high resolution, halftone or dither modulation can also be used in addition or in place of grayscale/color modulation, for printed representation of electronic document. For the detection, the document is acquired through an acquisition device, document segmentation is performed, characters/elements are segmented, the watermark signal is estimated and the information is decoded. Although the proposed scheme mostly addresses the watermarking of hard-copy documents, it can easily be integrated into electronic document editing and acquisition tools, and the watermark is attached to the document electronic version. The invention is applicable either using expensive high- resolution printing and acquisition devices, either using common cheap low-resolution devices, depending on the application needs.

Abstract: The present invention relates to the methods of estimation and recovering of general affine geometrical transformations which were applied to data, extensible to any other defined class of geometrical transformations, according to the preamble of the dependent claims. The parameters of the undergone deformation are robustly estimated based on maxima given by a parametric transform such as Hough transform or Radon transform of some embedded information with periodical or any other known regular structure. The main applications of this invention are robust digital still image/video watermarking, document authentication, and detection of periodical or hidden patterns. In the case of periodical watermarks, the watermark can also be predistorted before embedding based on a key to defeat block-by-block removal attack.

Abstract: A method of digital watermarking which can resist against local geometrical distortions such as random bending attack, global geometrical distortions as well as projective transforms, but does not necessary require the recovering of global affine transform or even the repetition of the same watermark pattern. Further, the watermark can resist common global affine transformations such as rotation, scaling, and changes of aspect ratio, cropping as well as other types of operations such as filtering, lossy compression, printing/scanning or detection of watermark in front of video, web or photo camera or any imaging device.

Abstract: The present invention relates to the methods of estimation and recovering of general affine geometrical transformations which were applied to data, extensible to any other defined class of geometrical transformations, according to the preamble of the dependent claims. The parameters of the undergone deformation are robustly estimated based on maxima given by a parametric transform such as Hough transform or Radon transform of some embedded information with periodical or any other known regular structure. The main applications of this invention are robust digital still image/video watermarking, document authentication, and detection of periodical or hidden patterns. In the case of periodical watermarks, the watermark can also be predistorted before embedding based on a key to defeat block-by-block removal attack.

Abstract: The present invention relates to the methods for hybrid watermarking method joining a robust and a fragile watermark, and thus combining copyright protection, authentication and tamperproofing. As a result this approach is at the same time resistant against the copy attack. In addition, the fragile information is inserted in a way which preserves the resistance and reliability of the robust part.