Abstract: The ability to remove a watermark from an encoded image opens the possibility of various novel applications. Several such applications are detailed. One employs a reversible watermark in conjunction with a second (robust) watermark. In this arrangement, the payload of the reversible watermark conveys information about the robust watermark (e.g., encoding parameters, or an error signal), permitting removal of the robust watermark from an uncorrupted encoded image. By such arrangements, the encoded image can be fully restored to its pristine, unencoded state even if several different watermarks have been applied.

Abstract: The present invention provides steganographic embedding and detecting techniques, along with related apparatus. One claim recites a signal detector including: an input and an analyzer. The input obtains media including a signal hidden therein. The signal including plural-bit data, the signal being hidden in the media through an arrangement of message objects. The arrangement is facilitated—at least in part—through thresholding of a steganographic signal representing or carrying the plural-bit data. The analyzer analyzes the media to obtain the plural-bit data. Of course, other combinations are provided and claimed as well.

Abstract: The ability to remove a watermark from an encoded image by reversible watermarking opens the possibility of various novel applications. Several such applications are detailed. One permits different classes of consumers to gain access to different versions of an image. A pristine image is intentionally degraded in some fashion, and distributed to consumers. By reference to one or more watermarks in the degraded image, some or all of the degradation can be removed, or transformed to a less-objectionable state. Through such arrangements, image consumers with different needs can gain access to versions of the image having differing qualities.

Abstract: This disclosure describes methods and systems for encoding a digital watermark into and/or detecting a digital watermark from a host (or media) signal such as audio, video or imagery. One implementation involves a method of detecting a digital watermark. The method includes: receiving a host signal carrying a digital watermark; computing attributes of the host signal; using the attributes of the host signal to compute a key; and using the key to detect the digital watermark in a transform domain dependent on the key. Other methods, systems and apparatus are provided as well.

Abstract: Novel methods and systems for quantization based data embedding and reading in host signals, such as image, audio and video signals. To embed auxiliary data in a host signal, an embedder maps the host signal from a first domain into a mapped signal in a second domain. The embedder performs quantization based embedding of auxiliary data into the host signal using quantizers. The quantizers are adapted such that the relationship between corresponding quantizers in the first and second domains satisfies a predetermined constraint. The mapping improves the robustness of the data embedding method by increasing the chances that the embedded data can be recovered by an auxiliary data reader after modifications. A related embedding method projects the mapped signal unto a vector, and specifically, a pseudorandom vector. It performs quantization based embedding on the projected signal. The use of this projection provides added robustness of the embedded data to noise and other forms of distortion.

Abstract: Certain forms of distortion make it difficult to recover hidden data embedded in an audio or image signal by quanitzation techniques. To compensate for this distortion, an embedded data reader analyzes a statistical distribution (e.g., a histogram) of feature samples (124) in an audio or image signal suspected of having hidden auxiliary data to derive an estimate of quantizers used to encode a reference signal (126). The estimated quantizers then recover the reference signal (126), and the reader uses the reference signal (126) to determine and compensate for geometric or temporal distortion, like spatial scaling and rotation of image data, and time scale and speed changes of audio data. After compensating for such distortion, the reader can then more accurately recover hidden message data using quantization techniques to extract the message. The reference signal (126) is preferably repeated in blocks of the image or audio data to enable synchronization at many points in an image or audio data stream.

Abstract: Novel methods and systems for quantization based data embedding and reading in host signals, such as image, audio and video signals. To embed auxiliary data in a host signal, an embedder maps the host signal from a first domain into a mapped signal in a second domain that is robust to a class of amplitude modifications that are order preserving. The embedder performs quantization based embedding of auxiliary data into the host signal using quantization bins derived from the second domain that are robust to the amplitude modifications. The mapping improves the robustness of the data embedding method by increasing the chances that the embedded data can be recovered by an auxiliary data reader after amplitude modifications. A related embedding method projects the mapped signal unto a vector, and specifically, a pseudorandom vector. It performs quantization based embedding on the projected signal. The use of this projection provides added robustness of the embedded data to noise and other forms of distortion.

Abstract: The present invention provides steganographic embedding and detecting techniques, along with related apparatus. One claim recites a signal detector including: an input and an analyzer. The input obtains media including a signal hidden therein. The signal including plural-bit data, the signal being hidden in the media through an arrangement of message objects. The arrangement is facilitated—at least in part—through thresholding of a steganographic signal representing or carrying the plural-bit data. The analyzer analyzes the media to obtain the plural-bit data. Of course, other combinations are provided and claimed as well.

Abstract: Digital watermarks embedded in objects enable watermark readers in vehicles to identify the objects and determine their orientation and location for use in navigation.

Abstract: The present invention provides steganographic embedding techniques. A digital watermark signal is reduced to a set of spatial positions. The set of spatial positions sufficiently conveys the digital watermark signal. Message objects are positioned according to the set of spatial positions. Non-message objects are combined with the message objects to form an image or design. The message objects include distinguishable characteristics, e.g., via color, contrast, gray-scale level or luminance, in comparison to the non-message objects. The digital watermark signal is detected by distinguishing the message objects from the non-message objects (e.g., via color or contrast differences) and analyzing the relative placement of the message objects within the image or design.

Abstract: The ability to remove a watermark from an encoded image opens the possibility of various novel applications. Several such applications are detailed. One employs a reversible watermark in conjunction with a second (robust) watermark. In this arrangement, the payload of the reversible watermark conveys information about the robust watermark (e.g., encoding parameters, or an error signal), permitting removal of the robust watermark from an uncorrupted encoded image. By such arrangements, the encoded image can be fully restored to its pristine, unencoded state even if several different watermarks have been applied.

Abstract: This disclosure describes methods and systems for encoding a digital watermark into and/or detecting a digital watermark from a host (or media) signal such as audio, video or imagery. One implementation involves a method of detecting a digital watermark. The method includes: receiving a host signal carrying a digital watermark; computing attributes of the host signal; using the attributes of the host signal to compute a key; and using the key to detect the digital watermark in a transform domain dependent on the key. Other methods, systems and apparatus are provided as well.

Abstract: The present invention relates to creating electronic versions of printed documents. A printed document will include steganographic, but machine-readable, indicia thereon. The steganographic indicia provides clues on how best to create a corresponding electronic version of the printed document.

Abstract: Reversible watermarking methods enable auxiliary data to be embedded in data sets, such as images, audio, video and software. The reversible nature of the method enables the original data set to be perfectly restored. Control systems with feedback loops are used to optimize embedding based on distortion or auxiliary data capacity constraints. The watermarking may be applied recursively to embed several layers, where subsequent layers are embedded into a previously watermarked data set. To recover the original data, each layer is extracted and the data restored in reverse order of the embedding. Sets of elements that are expanded to carry auxiliary data in each layer overlap or are interleaved to maximize embedding capacity or quality of the host data.

Abstract: The ability to remove a watermark from an encoded image opens the possibility of various novel applications. Several such applications are detailed. One employs a reversible watermark in conjunction with a second (robust) watermark. In this arrangement, the payload of the reversible watermark conveys information about the robust watermark (e.g., encoding parameters, or an error signal), permitting removal of the robust watermark from an uncorrupted encoded image. By such arrangements, the encoded image can be fully restored to its pristine, unencoded state even if several different watermarks have been applied.

Abstract: The present invention provides methods and systems for authenticating identification documents. We also teach an identification document including two or more digital watermarks. The watermarks correspond with each other or with indicia carried by the identification document. The correspondence can be verified to determine authenticity. We also provide digital watermark detection methods and systems to identify the different watermarks through embedded orientation components. We then focus watermark message-decoding efforts on areas identified as likely including watermark orientation components. In another implementation we provide a watermark detection trigger to identify so-called legacy documents. The trigger may indicate the presence or expected absence of a digital watermark. In other implementations we provide a versatile document authenticator to toggle between watermarking and non-watermarking authentication processes depending on a detection trigger. Other implementations are provided as well.

Abstract: A digital watermark is generated with radial and circumferential symmetries in a particular domain of a host signal into which it is embedded. These symmetries enable a detector to compute the projective transformation and rotation angle of the embedded signal using only the symmetry properties. The embedded signal may be variable, such as being modulated with a variable message payload, yet the scale and rotation of this variable signal is detectable based on its symmetry properties.

Abstract: Segmentation techniques are used in methods for embedding and detecting digital watermarks in multimedia signals, such as images, video and audio. A digital watermark embedder segments a media signal into arbitrary shaped regions based on a signal characteristic, such as a similarity measure, texture measure, shape measure or luminance or other color value extrema measure. The attributes of these regions are then used to adapt an auxiliary signal such that it is more effectively hidden in the media signal. In one example implementation, the segmentation process takes advantage of a human perceptibility model to group samples of a media signal into contiguous regions based on their similarities. Attributes of the region, such as its frequency characteristics, are then adapted to the frequency characteristics of a desired watermark signal. One embedding method adjusts a feature of the region to embed elements of an auxiliary signal, such as an error correction encoded message signal.

Abstract: This disclosure describes a method for encoding a digital watermark into an image signal that is robust to geometric distortion. The digital watermark is adapted to the host image signal in which it is embedded so as to be imperceptible or substantially imperceptible in the watermarked image when displayed or printed. This digital watermark may be used to determine the geometric distortion applied to a watermarked image, may be used to carry auxiliary information, and may be used to detect and decode a digital watermark embedded in a geometrically distorted version of a watermarked image. Because of its robustness to geometric distortion, the digital watermark is useful for a number of applications for embedding auxiliary data in image signals, including still pictures and video, where the image signal is expected to survive geometric distortion. This method may adapted to other types of media signals such as audio.

Abstract: Reversible watermarking methods enable auxiliary data to be embedded in data sets, such as images, audio, video and software. The reversible nature of the method enables the original data set to be perfectly restored. Control systems with feedback loops are used to optimize embedding based on distortion or auxiliary data capacity constraints. The watermarking may be applied recursively to embed several layers, where subsequent layers are embedded into a previously watermarked data set. To recover the original data, each layer is extracted and the data restored in reverse order of the embedding. Sets of elements that are expanded to carry auxiliary data in each layer overlap or are interleaved to maximize embedding capacity or quality of the host data.