Methods, apparatus, systems and articles of manufacture are disclosed to perform symbol-based watermark detection. An example method includes, in response to determining that a first rate of occurrence of a first potential symbol equals a second rate of occurrence of a second potential symbol, a first accumulated signal to noise ratio value corresponding to occurrences of the first potential symbol value is determined. A second accumulated signal to noise ratio value corresponding to occurrences of the second potential symbol value is determined. One of the first potential symbol value or the second potential symbol value having a greatest accumulated signal to noise ratio value as the likely symbol value is selected. The likely symbol value is concatenated with other likely symbol values corresponding to other symbols of the watermark to detect the watermark.

Vision sensor dynamic watermarking via noise characterization are disclosed herein. An example device can capture an image by a first device, where the image comprising a pixel group has baseline noise characterization caused by a base noise profile for the first device. The device can produce a noise watermark to create a watermarked image, where the noise watermark can be produced by altering the baseline noise characterization to produce modified noise characterization. The device can also transmit the watermarked image to a receiver.

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.

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.

A system for generating and detecting watermarks within a video frame (e.g., video content) is described to determine whether a data interruption has occurred. In one or more implementations, the system includes a generation module communicatively coupled to a video source and a watermark detection module configured to receive a plurality of video watermarks. The watermarking detection module is configured to determine whether a watermark embedded in a current (e.g., a second) video frame is different from a watermark embedded in the previous (e.g., a first) video frame. The watermarking detection module is configured to generate an error signal when the watermark embedded in the current (e.g., a second) video frame is not different than the watermark embedded in the previous (e.g., a first) video frame to indicate a data interruption event has occurred.

An information processing apparatus includes circuitry that determines whether or not an image described based on image data is continuous with an area where watermark information is to be embedded to generate a determination result and changes, in accordance with the determination result, the area where the watermark information is to be embedded.

An image forgery protection apparatus comprises: one or more memories; and circuitry. The circuitry generates challenge data which change with lapse of time at least in a predetermined period. The circuitry generates a unique response which changes with lapse of time, the unique response corresponding to the challenge data on a basis of a physically unclonable function. The circuitry changes subject image data correspondingly to the unique response, the subject image data obtained by capturing an image of a subject.

One aspect of the present invention discloses a watermark insertion method. The method includes: segmenting target text into pieces of page content; obtaining a watermark variable comprising a line alternation value indicative of a watermark mode changed for each line of the segmented page content and a watermark mode setting value; and applying a flip-flop component insertion algorithm for inserting a watermark into each of the pieces of segmented page content based on the obtained watermark variable.

The present document provides image processing methods and apparatus. One claim recites: obtaining a signal to be encoded in color image data, the signal comprising a plural-bit payload; predicting a resulting color of overprinting several inks on a substrate, the overprinting representing the color image data encoded with the signal; using the resulting color for both i) visibility evaluation of the overprinting, and ii) signal robustness evaluation of the overprinting as seen by an imaging device. Other claims and combinations are provided.

The disclosure describes methods and apparatus of providing steganographic indicia or digital watermarking in image or video data. One implementation provides a method of embedding a digital watermark in image data captured by an imager, with watermark embedding occurring on-chip with the imager. Another implementation provides a method of managing images. Each of the images comprises plural-bit data steganographically embedded therein in the form of a digital watermark, with the plural-bit data corresponding to a geo-location. Yet another implementation provides a method of identifying locations on a map, with the map being for display via a computer display. Still another implementation provides a method of introducing a watermark message to a watermark embedder located on-chip with an image array. Other implementations and embodiments are provided as well.