Digimarc Corporation

Other

Digimarc Coporation

Ammon E Gustafson

Geoffrey B Rhoads

Ravi K Sharma

Tony F Rodriguez

Alastair M Reed

Robert G Lyons

Kenneth Lee Levy

Hugh L Brunk

Brett T Hannigan

Osama M Alattar

Marc D Miller

Clay Davidson

Adnan V Alattar

This disclosure describes methods for using embedded auxiliary signals in documents for copy detection and other applications. In on application, the auxiliary signal is formed as an array of elements selected from a set of print structures with properties that change differently in response to copy operations. These changes in properties of the print structures that carry the embedded auxiliary signal are automatically detectable. For example, the changes make the embedded auxiliary signal more or less detectable. The extent to which the auxiliary data is detected forms a detection metric used in combination with one or more other metrics to differentiate copies from originals. Examples of sets of properties of the print structures that change differently in response to copy operations include sets of colors (including different types of inks), sets of screens or dot structures that have varying dot gain, sets of structures with different aliasing effects, etc. Robust and fragile watermarks are used in Image Replacement Documents for a variety of applications. Digital watermarks act as on-board mediators in authentication of a variety of printed documents. Finally, digital watermarks are used to help manage quality of the scanners used in imaging systems.

Automated methods for distinguishing copies from original printed objects

The present disclosure relates generally to digital watermarking. One claim recites an apparatus including: an input for receiving imagery or video; and an electronic processor for processing received imagery or video. The electronic processor is programmed for detecting first digital watermarking and second digital watermark from the imagery or video, in which the first digital watermarking utilizes a relationship between at least a first color space and a second color space. Another claim recites an apparatus including: an input for receiving imagery or video; and an electronic processor for processing received imagery or video. The electronic processor is programmed for embedding first digital watermarking and second digital watermark in the imagery or video, in which the first digital watermarking comprises a geometrically linear assignment of pixels, while the second digital watermarking comprises a geometrically random assignment of pixels. Of course other claims and combinations are provided too.

Apparatus to process images and video

The present invention generally relates to processing audio, video and images. One claim recites a method including: obtaining media signal comprising a steganographic signal hidden therein; utilizing a programmed electronic processor, selecting portions of the media signal for steganographic signal detection, wherein the subset of the media signal is selected based on at least one or more predetermined probability factors, in which a probability factor comprises a selection criteria or rule to identify portions of the media signal which have a higher likelihood of including a steganographic signal relative to other portions of the media signal; and utilizing a programmed electronic processor, analyzing selected portions of the media signal to obtain the steganographic signal. Of course, other claims and combinations are provided as well.

Signal processing utilizing host carrier information

A digital watermark detector comprises a memory buffer for receiving an incoming stream of data. The detector includes a registration module for determining registration of embedded data in blocks of the incoming stream of data, and logic for re-using the registration for subsequent blocks of the incoming stream of data to detect machine readable signals. Another digital watermark detector comprises a message reader for extracting message estimates from blocks of media signal data and a decoder for combining the extracted message estimates and decoding a message from the combined message elements. Another digital watermark detector comprises a memory buffer and pipelined watermark processor segments. The segments each perform a different watermark detector operation. These segments concurrently operate on different data segments of the block of data in a processing pipeline.

Optimized digital watermarking functions for streaming data

The present invention generally relates to digital watermarking and steganography. In one implementation, a method is provided including acts of receiving a media signal comprising a steganographic signal redundantly embedded therein; selecting a subset of the media signal for steganographic signal detection, wherein the subset of the media signal is selected based on at least one media signal characteristic associated with the subset; and detecting a steganographic signal hidden in the subset of the media signal. In another implementation, a digital watermark detector is providing including: electronic processing circuitry; memory; and executable instructions stored in memory for execution by said electronic processing circuitry. The instructions comprises instructions to: process a media signal comprising a digital watermark redundantly embedded therein; select a subset of the media signal for watermark detection, wherein the subset of the media signal is selected based on at least one media signal characteristic associated with the subset; and detect a digital watermark hidden in the subset of the media signal.

Digital watermark detection utilizing host carrier information

Two or more digital watermarks are embedded in a document. In one implementation the digital watermarks include characteristics that are chosen so that the watermarks will be affected in different manners if the document is subsequently copied or reproduced. A detection method or mechanism reads two or more of the watermarks and compares their characteristics. In another claim, two or more digital watermarks correspond to characteristics that are evaluated for authentication. Of course, other claims are provided as well.

Documents and methods involving multiple watermarks

In one aspect of the invention, a digital watermark detector comprises a memory buffer for managing an incoming stream of data. The detector includes logic for transferring overlapping data blocks from the memory buffer to a frequency domain transform processor, such as an FFT processor. The frequency domain transform processor including logic to re-use frequency domain transform operation results for overlapping portions of the data blocks. In another aspect of the invention, a digital watermark detector comprises a memory buffer for a block of data, and pipelined watermark processor segments. The segments each perform different watermark detector operations in series. These segments concurrently operate on different data segments of the block of data in a processing pipeline. One embodiment employs pipelined processors for setting up data for subsequent detecting stages, such as pipelined data conversion, re-sampling, pre-filtering and frequency domain transforms. Alternative embodiments pipeline data transformations, correlation operations (e.g., matched filter operations) etc. Data flows through the processing pipeline until it reaches a critical point. At stages before the critical point, data may be dropped as not likely to include digital watermark data. This pruning of data helps reduce un-needed processing and/or false positives of watermark detection.

The present invention relates generally to steganographic encoding and/or digital watermarking. In one embodiment, a method is provided including: obtaining an image or video; encoding a first steganographic component in the image or video, wherein the first steganographic component comprises a first set of properties that are designed to be affected in a first manner when transformed from a first color gamut to a second color gamut; and encoding a second steganographic component in the image or video, wherein the first steganographic component comprises a second set of properties that are designed to be affect in a second manner when transformed from the first color gamut to the second color gamut. Other implementations and embodiments are provided and claimed as well.

Methods to evaluate images, video and documents

Image, video, and/or audio data is encoded with at least first and second watermarks. In one implementation a method includes: receiving content; embedding a first watermark signal in the content; compressing the content; embedding a second watermark signal in the content. The first watermark signal and the second watermark signal are designed to respond differently to at least a first type of signal processing. Other implementations are also provided.

Multiple watermarks in content

A fragile watermark is embedded in a document. The fragile watermark provides enhance security. In one implementation, a method is provided for embedding information in an image so that the image will have different information when a scanning or printing process reproduces the image. The method includes embedding digital information in an image; printing the embedded digital information and the image to produce a original printed image; scanning the original printed image to obtain a digital image of the embedded information and the image; determining the signal strength of the original image; and comparing the signal strength of a printed image with the signal strength of the original printed image to determine whether or not the printed image is a copy of the original printed image.

Method for utilizing fragile watermark for enhanced security

Image, video, or audio data is encoded with both a frail and a robust watermark. The two watermarks respond differently to different forms of processing (e.g., copying the object may render the frail watermark unreadable), permitting an original object to be distinguished from a processed object. Appropriate action can then taken in response thereto.

Data encoding using frail watermarks

Inferring object status based on detected watermark data

The present invention detects the presence of a digital watermark in an image by selecting regions within the image having a high probability of containing the watermark. The image is examined to determine which regions of the image have characteristics indicating that there is a high probability that a watermark signal can be detected in that region of the image. The regions that have a high probability that a watermark can be detected (in contrast to all regions of the image) are examined to find watermark data. Probability factors used to select detection regions include: requiring a minimum variance separation between detection blocks; requiring a minimum distance between overlapping blocks; segmenting the detection blocks into a first and second subset based on separate criteria; establishing a keep away zone to prevent selection of a detection block near an image's border; and selecting a detection block only after its neighbors met sufficient threshold requirements. These probability factors can be used separately or in conjunction to determine those regions of an image that have characteristics indicating a high probability that a watermark signal can be detected therein.

Watermark detection utilizing regions with higher probability of success

A watermark embedder encodes auxiliary information, such as a binary message, into a host media signal by modulating message signals with two or more corresponding carrier signals to form a watermark signal and embeds this signal into the host. A compatible watermark decoder uses the carrier signals to demodulate the message signals from the watermarked signal.

Growing community of inventors

Beaverton, OR, United States of America

Ammon E Gustafson