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.

The present disclosure provides for methods, apparatus and computer readable media related to screen-capture communication based on invisible watermark. An aspect of the disclosure provides for a method including inserting one or more templates into one or more frames of a video for correcting frame perspective of the one or more frames captured by a device. The method further includes writing a message into the one or more frames of the video and displaying the video. According to a second aspect, a second method is provided. The second method includes capturing one or more frames of a video displayed on a device comprising a hidden message. The method further includes locating one or more templates and correcting frame perspective of the captured frames based on the templates. The method further includes extracting the message from the one or more frames of the video.

In an embodiment, a method of rendering an infrared mark, can involve providing an image path for an image processing apparatus, wherein the image path integrates infrared mark related functions with regular image processing functions of the image processing apparatus, and rendering the infrared red mark with the image processing apparatus, after subjecting the infrared mark to the infrared mark related functions in the image path of the image processing apparatus.

A monochrome imager used in such systems as a scanner can detect watermarks that have been encoded in the color space or chrominance. Such watermarks are called chroma watermarks and are considered more reliable than the traditional classic watermarks, which are encoded based on luminance. The monochrome imager detects the chroma watermark, which has been illuminated with ambient white light from a blue light emitting diode (LED) coated with phosphor.

A method of providing robust and secure fingerprints including, at an enrollment stage, the steps of providing a content x for which a fingerprint is to be provided, assigning an ID number to the content x, providing a secret key k, generating a fingerprint b.sub.x based on content x and secret key k, storing the generated fingerprint b.sub.x together with the assigned ID in a database, as well as, at an identification stage, the steps of extracting, for a given query content y which might result either from the enrolled content x or an unrelated content x′, an estimate fingerprint b.sub.y based on content y, and secret key k, producing an estimated I{hacek over (D)} number based on the estimate fingerprint b.sub.y for identifying the content x using said ID number stored in the database, or else rejecting the query.

A reception apparatus, method, and non-transitory computer-readable storage medium for processing an image in which a plurality of symbols is encoded, and an information providing apparatus for providing the image. The reception apparatus includes circuitry configured to receive or retrieve an image in which a plurality of symbols is encoded. The circuitry determines a set of luminance values used to encode the symbols based on luminance values of a plurality of pixels included in the image. The circuitry determines a highest luminance value used to encode the symbols in the image based on the determined set of luminance values. Further, the circuitry derives data values of the symbols encoded in the image based on the set of luminance values and using the determined highest luminance value.

In some arrangements, product packaging is digitally watermarked over most of its extent to facilitate high-throughput item identification at retail checkouts. Imagery captured by conventional or plenoptic cameras can be processed (e.g., by GPUs) to derive several different perspective-transformed views—further minimizing the need to manually reposition items for identification. Crinkles and other deformations in product packaging can be optically sensed, allowing such surfaces to be virtually flattened to aid identification. Piles of items can be 3D-modelled and virtually segmented into geometric primitives to aid identification, and to discover locations of obscured items. Other data (e.g., including data from sensors in aisles, shelves and carts, and gaze tracking for clues about visual saliency) can be used in assessing identification hypotheses about an item. Logos may be identified and used—or ignored—in product identification. A great variety of other features and arrangements are also detailed.

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.

Providing secure graphics outputs by performing at least the following: receive secure output data corresponding to a digital image, obtain one or more security keys, create a secure output marker for the secure output data, wherein the secure output marker comprises location information corresponding to a trusted output area of the digital image and data information that represents data content found within the trusted output area of the digital image, encrypt the secure output marker using the one or more security keys, embed the secure output marker within the graphics image to create a trusted graphics image; and render the trusted graphics image for exposure onto the display device.

Image processing technology embeds signal (e.g., digital watermarks) within imagery during a raster image process(or). One claim recites: an image processing method of embedding a signal within imagery using raster image processing (RIP), including: obtaining a plurality of elements representing a signal; determining edges within the imagery; using the determined edges as a reference, modulating a plurality of print structures within the RIP according to the plurality of elements to embed the signal within the imagery, in which one determined edge defines the signal to be at a predetermined angle in a set of dimensions comprising color and spatial frequency. Of course, other claims, combinations and technology are described too.