Systems and methods are described for obfuscating variants of content segments. Variants of content segments can be used to encode an identifying sequence in a transmission of content. The variants of the content segments can each include one or more marked frames and one or more unmarked frames. Variations can be introduced into the unmarked frames for each of the variants of the content segments.

A method for authenticating digital information includes obtaining, in digital form, information for authentication; preparing the information for processing, such preparation including converting the information into a digital image; identifying segments of content in the digital image; grouping the segments of content into one or more segment groups; generating a marking sequence comprising shifting at least one of the one or more segment groups in one or more directions; and applying the marking sequence to the digital image, creating a unique marked copy of the digital image.

Artwork carrying machine readable data is generated by editing artwork according to a data signal or transforming the data signal into artwork. The machine-readable data signal is generated from a digital payload and converted into an image tile. Artwork is edited according to the image tile by moving graphic elements, adapting intersections of lines, or altering line density, among other techniques. Artwork is generated from the data signal by skeletonizing it and applying morphological operators to a skeletal representation, such as a medial axis transform. Artistic effects are introduced by filtering the data signal with directional blurring or shape filters.

A watermark encoder receives a current video image together with current metadata associated with the current image. A metadata delay also makes available to the watermark decoder delayed metadata associated respectively with four or more of the preceding. Then the watermark encoder modifies pixel values of the current image not only to encode the current metadata but also the delayed metadata. At a decoder, if metadata for the current image is corrupted or missing, it can be recovered from one of the succeeding images.

An example implementation includes an apparatus including a processor to divide a digital image into a grid including a first grid region and a second grid region. The processor is also to generate a first grid-based watermark using shared watermark information and a first set of grid coordinates associated with the first grid region. The processor is further to generate a second grid-based watermark using the shared watermark information and a second set of grid coordinates associated with the second grid region. The processor is further to embed the first grid-based watermark into a first region of the digital image corresponding to the first grid region and to embed the second grid-based watermark into a second region of the digital image corresponding to the second grid region. The processor is further to generate a machine-readable digital image including the embedded first grid-based watermark and the embedded second grid-based watermark.

Optical code signal components are generated and then transformed into signal bearing art that conveys machine readable data. The components of an optical code are optimized to achieve improved signal robustness, reliability, capacity and/or visual quality. An optimization program can determine spatial density, dot distance, dot size and signal component priority to optimize robustness. An optical code generator transforms tiles of an optical code or image embedded with the optical code into signal-bearing art using stipple, Voronoi, Delaunay or other graphic drawing methods so as to retain prioritized components of the optical code. The optical code is merged into a host image, such as imagery, text and graphics of a package or label, or it may be printed by itself, e.g., on an otherwise blank label or carton. A great number of other features and arrangements are also detailed.

The present disclosure relates to signal decoding and icon (e.g., a logo, shape, icon, etc.) detection. In some implementations, a series of filters are applied to scanlines to determine whether an icon is present. Other aspects, combinations and implementations are described as well.

An image processing apparatus includes: an embed-data generating unit configured to generate embed-data, which is to be embedded in input-image-data, the input-image-data representing an image including a first color, the embed-data representing an image including a second color; an inverting unit configured to invert the image represented by the embed-data, in response to meeting a predetermined condition relating to the first color and the second color; and an output-image-data generating unit configured to embed, in the input-image-data, embed-data representing the image that is inverted by the inverting unit, in order to generate output-image-data in a case where the predetermined condition is met, and configured to embed, in the input-image-data, embed-data representing the image that is not inverted by the inverting unit, in order to generate output-image-data in a case where the predetermined condition is not met.

Provided are a template-based watermarking method for a DIBR 3D image and an apparatus thereof. The method includes: determining a template watermark inserting area and a message watermark inserting area in spatial domain of an image; transforming the determined template watermark inserting area into a frequency domain to insert at least one preset template watermark and transforming the determined message watermark inserting area into a frequency domain to insert a preset message watermark; and transforming the template watermark inserting area, into which the template watermark is inserted, into a spatial domain and transforming the message watermark inserting area, into which the message watermark is inserted, into a spatial domain.

Differential modulation schemes encode a data channel within host signal or noisy environment in a manner that is robust, flexible to achieve perceptual quality constraints, and provides improved data capacity. Differential arrangements enable a decoder to suppress host signal or other background signal interference when detecting, synchronizing and extracting an encoded data channel. They also enable the incorporation of implicit or explicit synchronization components, which are either formed from the data signal or are complementary to it.