Certain examples described herein relate to the embedding a pattern in an output content having at least two-dimensions, for example a printed output. Content data having at least two dimensions is processed to generate an array of spatial elements, each spatial element corresponding to a respective location in the output content and comprising a probabilistic distribution for a set of output material compositions. A threshold matrix is generated using pattern data corresponding to a pattern, and the array of spatial elements is halftoned using the threshold matrix. The threshold matrix is generated such that the pattern is embedded in the output content.

Digital watermarking is adapted for the variable data printing. A reference signal serves as a proxy for optimizing the embedding a watermark in a host image to be printed. Using the reference signal, embedding parameters are generated, which are a function of constraints such as visual quality and robustness of the machine readable data. Adjustments needed to embed a unique payload in each printed piece are generated using the embedding parameters. These adjustments are stored in a manner that enables them to be efficiently obtained and applied within the RIP or press during operation of the press. Various other methods, system configurations and applications are also detailed.

Digital signature authentication systems and methods are disclosed. An example method of authenticating a digital signature extracted from a high resolution image includes comparing an extracted signature from an image to a reference signature. The example method also includes authenticating the extracted signature against the reference signature according to one of a plurality of different authentication protocols.

The present disclosure discloses methods and systems for detecting an IR security mark in a document based on known color information and halftone frequency information. The method includes receiving a document from a user, including an IR security mark. Then, location information, color information and halftone frequency information are received from the user. The document is scanned. Based on the color information and the location information, the IR security mark is extracted from the scanned document. After this, halftone frequency information of the extracted IR security mark is verified. Based on the verification, text in the extracted IR security mark is identified and is then compared with one or more pre-stored IR security marks to ascertain whether the IR security mark in the document is an authentic security mark.

In an example, a method includes obtaining, by at least one processor, a first halftone screen tile having a first halftone pattern. In some examples, the method further comprises obtaining a second halftone screen tile having a second halftone pattern. The method may include determining a halftone screen having a predetermined spatial arrangement of the first and second halftone screen tiles wherein the relative placement of the first and second halftone screen tiles in the predetermined spatial arrangement provides a signature for the halftone screen which when applied to image data provides a printed output in which the signature is discernible.

A copy-evident document and a method of printing a copy-evident document wherein a void pantograph is created including a first set of halftone elements and a second set of halftone elements different in modulation from the first set of halftone elements. An overlay including a white image with a plurality of halftone hole locations is preferably formed, wherein the halftone elements of the void pantograph are converted to the plurality of halftone hole locations. The overlay is then preferably merged with a background image, such that portions of the background image are visible at the halftone hole locations of the overlay when printed. The merged image is then printed on print media, wherein the portions of the background image that are printed are printed at locations where the holes locations are present in the overlay creating a copy-evident feature.

An information processing apparatus and an image processing method are provided. The image processing apparatus detects character data from image data, executes edge enhancement processing, using a first filter, on an edge portion of a region, out of the detected character data, that includes a region whose frequency of points or lines is greater than a predetermined frequency, and executes edge enhancement processing, using a second filter, on an edge portion of a region, out of the detected character data, that does not include a region of a spatial frequency higher than the predetermined frequency. The first filter has, in comparison to the second filter, a larger degree for edge enhancement with respect to a region having a frequency higher than the predetermined frequency.

Digital watermarking is adapted for the variable data printing. A reference signal serves as a proxy for optimizing the embedding a watermark in a host image to be printed. Using the reference signal, embedding parameters are generated, which are a function of constraints such as visual quality and robustness of the machine readable data. Adjustments needed to embed a unique payload in each printed piece are generated using the embedding parameters. These adjustments are stored in a manner that enables them to be efficiently obtained and applied within the RIP or press during operation of the press. Various other methods, system configurations and applications are also detailed.

In an example, a method includes, at least one processor, in response to each of a plurality of requests, determining a halftone screen. Determining the halftone screen comprises encoding a signature pattern in the halftone screen, and halftone screens for different requests may be encoded with a different signature pattern. The halftone screen may be arranged such that, when applied to image data to provide a printed output, the pattern is discernible therein to provide a signature for the printed output.

A computer implemented method for generating at least one security label (110) using at least one printing device (112) is proposed. The method comprises the following steps: i) (114) generating a first digital image (116) comprising a plurality of colored pixels by printing a printer job with a printer control setting and scanning the printout using the printing device (112) thereby generating a digital fingerprint: ii) (118) providing a binary code (120) of identifier information: iii) (122) mapping the identifier information with the digital fingerprint by determining a binary code of the digital fingerprint and adding the binary code (120) of the identifier information to the color code of the first digital image (116); iv) (124) generating a second digital image (126) having a plurality of colored pixels different from the first digital image (116) by transferring the added binary codes into a color code of the second digital image (126): v) (128) printing the second digital image (126) on a substrate (129) thereby generating the security label (110).