A system includes circuitry configured to embed a digital watermark data in an original image, wherein the original image is divided into a plurality of blocks each block having been embedded with a pattern corresponding to each value of the digital watermark data, store, in a memory, the original image, the digital watermark data embedded in the original image, and an embedding position of the pattern of the digital watermark data in association, detect a pattern in a scanned image of a printed matter, decode the detected pattern to acquire digital watermark data included in the scanned image, align each block between the original image and the scanned image, based on the embedding position of the pattern associated with the original image and a detection position of the pattern detected from the scanned image, and obtain a difference between the original image and the scanned image aligned with each other.

Methods for designing and producing a security feature are provided. In general, the present disclosure provides methods of designing a printed image in a security feature, the security feature comprising an array of optical elements overlaying the printed image, wherein the printed image comprises a two dimensional matrix of rows and columns of pixels, the method comprising; correcting for a mismatch between the pixels of the printed image and the array of optical elements by doing one or more of: adding one or more pixels; removing one or more pixels; and moving one or more pixels.

The present disclosure relates generally to encoding signals for spot colors. In one implementation a substitute spot color+CMY tint is selected to replace an original spot color. The CMY tint can be transformed to carry an encoded signal. Of course, other features, combinations and technology are described herein.

The present invention relates generally to digital watermarking. One aspect of the disclosure includes a method comprising: obtaining data representing imagery; using one or more configured processors, analyzing a plurality of portions of the data to detect a redundantly embedded watermark signal, the analyzing producing detection statistics for each of the plurality of portions, the detection statistics comprising a payload signature, a rotation angle and a scale factor for each portion of the plurality of portions; accumulating payload signatures based on compatible rotation angles and scale factors, said accumulating yielding an accumulated payload signature; and decoding a plural-bit payload from the accumulated payload signature. Of course, many other aspects and disclosure are provided in this patent document.

The present disclosure relates generally to data hiding for retail product packaging and other printed objects such as substrates. One embodiment embeds an information signal in a spot color for printing on various substrates. The spot color is screened, and overprinted with process color tint. The tint is modulated prior to overprinting with optimized signal tweaks. The optimization can include consideration of a detector spectral dependency (e.g., red and/or green illumination). Many other embodiments and combinations are described in the subject patent document.

A computerized method for authenticating documents having VIZ sections, the method comprising capturing an image of a document to be authenticated from a scanner and enhancing the captured image, and using a processor for identifying and cropping a VIZ section in the image.

A method for identifying whether a standard picture contains a watermark is provided. After obtaining a set of sample standard pictures, one or more sample pictures in the set of sample standard pictures are adjusted to a preset size. The sample pictures in the set of sample standard pictures do not contain watermark information. Next, an average of pixel attribute values of the sample pictures at pixel positions of the preset size is calculated. The average of the pixel attribute values at the pixel positions of the preset size is normalized to obtain the watermark-presence probabilities of the pixel positions of the preset size. Then, a target picture is adjusted to the preset size and a sum of products of pixel attribute values of the target picture at the pixel positions of the preset size and the corresponding watermark-presence probability are calculated. Finally, it is determined whether the target picture contains a watermark according to the sum of products.

An image processing apparatus includes: an image processor; and a hardware processor that converts a read image, obtained by optically reading printed paper, into a file by performing image processing. A content of the image processing, including position adjustment or gradation adjustment, is changed in accordance with an analysis result obtained by analyzing the read image.

The present disclosure relates generally to encoding signals for spot colors. In one implementation a substitute spot color+CMY tint is selected to replace an original spot color. The CMY tint can be transformed to carry an encoded signal. Of course, other features, combinations and technology are described herein.

A system and method for localizing an area of interest likely containing a digital watermark is disclosed. Image frames may be segmented into multiple tiles. A pixel having the maximum grayscale or other value and a pixel having the minimum grayscale or other value in each tile may be identified. Maximum and minimum image maps may be generated from the image frame by replacing each tile with the respective maximum and minimum grayscale or other value pixels. A background map may be generated based on a moving average of the grayscale values of the pixels in the image maps. Foreground map(s) may be generated based on the difference of the values from the image maps to the background map. A region of interest may be determined based on the background and foreground maps and provided to a watermark decoder. Content contained in the digital watermark may be read.