An image processing apparatus capable of changing a halftone pattern set to a coding pattern that will be synthesized with an image to another halftone pattern that can uniformly generate the coding pattern when the coding pattern cannot be uniformly generated in performing a halftone process using the halftone pattern set to the cording pattern. A setting unit sets a halftone pattern used in a halftone process from among a plurality of halftone patterns. A determination unit determines whether a coding pattern can be uniformly generated when the halftone process is performed using the halftone pattern set by the setting unit as the coding pattern to be synthesized with an image to be printed. A changing unit changes a halftone pattern used in the halftone process to another halftone pattern capable of uniformly generating the coding pattern when the determination unit determines that the coding pattern cannot be uniformly generated.

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.

The invention describes a method for protecting the authenticity of an object, item, document, packaging and/or a label from imitation, forgery and theft, whereas during such marking by means of graphic halftone visually encoded image keeping qualitative-quantitative data of an subject and containing a hidden verification hash code in the form of a digital watermark (DWM), square data cells of the cross-linked structure of the graphic halftone image with identical brightness values are revealed in the entire area inside the revealed square data cell, thereafter a square-cross-linked mask is formed to store the base of the revealed readable data cells, the applied digital watermark (DWM) is read and opposed by means of comparison of the brightness of color components of the central of the revealed readable data cell against the arithmetic mean value of the brightness of the components of the eight neighbor squares surrounding the revealed readable data cell.

Methods and systems for securely rendering a security feature with image data to be printed, can involve providing within the image data, data relating to a group of spots, and within the image data, mixing spots of two or more spot sizes among the group of spots to embed information within a stochastic or frequency modulation halftone image. In an embodiment, operations may be implemented for rendering a part of the image with a first spot among the group of spots and a remaining portion of the image with a second spot among the group of spots, wherein the second spot is smaller in size than the first spot.

A method of printing authentication indicia by applying an at least amplitude-modulated halftone print in a detection zone to an object uses adjoining halftone cells, in each of which a halftone dot is printed from a matrix of printable halftone elements, individual tone values of the halftone print corresponding in each case to a halftone plane of a halftone mountain for a halftone dot. In this process, the assigned screen plane of the screen mountain is modified in the detection zone in a predetermined manner for a plurality of tone values of screen dots to be printed, so that a predetermined matrix image of the screen elements to be printed is assigned to it while the tone value of the print remains constant.

A data-bearing medium has an array of data-bearing elements. The array of data-bearing elements represents an array of bits. A certain number of the bits repeat within the array of bits. Positions of the bits in each row of the array of bits are circularly shifted from positions of the bits in an immediately preceding row.

Gloss effect image patterns are created by creating a solid color background and overprinting the solid color background with the glossmark. In creating the glossmark, a background base of an electronic image region is painted with a solid color corresponding to a color of a marking material; using a first electronic pattern ink, a background of the electronic image region is painted without knocking out the solid color of the background base of the electronic image region; and using a second electronic pattern ink, a foreground in the electronic image region is painted without knocking out the solid color of the background base of the electronic image region such that a pattern in the rendered image area is only visible when a predetermined angle between an observer's viewing angle and an angle of illuminating the rendered recording medium by an illumination source is realized.

A method for generating a data-bearing image is implemented by an encoding system including a halftoning module and an encoding module that stores encoding rules associated with respective codes. In the method, the halftoning module converts a grayscale image into a halftone image having a plurality of image cells each consisting of a plurality of dots, at least one of which is a first-tone dot and each of the rest of which is a second-tone dot. Afterward, the encoding module generates a data-bearing halftone image encoded with at least one of the codes by maintaining or changing the number of the first-tone dots in one of the image cells based on one of the encoding rules associated with the at least one of the codes.

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.

Variable data printing workflows are enhanced for use with content that includes 2D code patterns, such as digital watermark data. One arrangement includes applying a filter to a content stream within a PDF document to extract both first variable pattern data for a first watermark pattern and second variable pattern data for a second watermark pattern. A first composite watermark pattern is then defined based on the extracted first variable watermark pattern data in conjunction with static watermark pattern data, and a second composite watermark pattern is defined based on the extracted second variable watermark pattern data in conjunction with the static watermark pattern data. A variety of other features and arrangements are also detailed.