Abstract: Digital data is optically broadcast through an environment by controllably switching the brightness or chrominance of LED solid state lamps, or of other illumination sources (e.g., television screens and backlit computer displays). This optical data channel is useful to convey cryptographic key data by which devices within the environment can authenticate themselves to a secure network. In some embodiments, the optical modulation is sensed by the camera of a smartphone. The row data output by the smartphone's camera sensor is processed to extract the modulated data signal. In some monochrome embodiments, data communication speeds far in excess of the camera's frame rate (e.g., 30/second), or even the camera's row rate (e.g., 14,400/second) are achieved. Still greater rates can be achieved by conveying different data in different chrominance channels. A great number of other features and arrangements are also detailed.

Abstract: In one embodiment, a first set of digital data (e.g., an image) is tested for the presence of a certain feature (e.g., a certain face), yielding one of two outcomes (e.g., not-present, or present). If the testing yields the first outcome, no additional testing is performed. If, however, the testing yields the second outcome, further testing is performed to further check this outcome. Such further testing is performed on a second set of digital data that is based on, but different from, the first set of data. Only if the original testing and the further testing both yield the same second outcome is it treated as a valid result. A variety of other features and arrangements are also detailed.

Abstract: Digital data is optically broadcast through an environment by controllably switching the brightness or chrominance of LED solid state lamps, or of other illumination sources (e.g., television screens and backlit computer displays). This optical data channel is useful to convey cryptographic key data by which devices within the environment can authenticate themselves to a secure network. In some embodiments, the optical modulation is sensed by the camera of a smartphone. The row data output by the smartphone's camera sensor is processed to extract the modulated data signal. In some monochrome embodiments, data communication speeds far in excess of the camera's frame rate (e.g., 30/second), or even the camera's row rate (e.g., 14,400/second) are achieved. Still greater rates can be achieved by conveying different data in different chrominance channels. A great number of other features and arrangements are also detailed.

Abstract: Methods and arrangements involving portable user devices such smartphones and wearable electronic devices are disclosed, as well as other devices and sensors distributed within an ambient environment. Some arrangements enable a user to perform an object recognition process in a computationally- and time-efficient manner. Other arrangements enable users and other entities to, either individually or cooperatively, register or enroll physical objects into one or more object registries on which an object recognition process can be performed. Still other arrangements enable users and other entities to, either individually or cooperatively, associate registered or enrolled objects with one or more items of metadata. A great variety of other features and arrangements are also detailed.

Abstract: In one particular arrangement, a smartphone camera is moved by a user to capture dermatologic imagery from a variety of viewpoints. When the user thereafter holds the phone in a particular pose (e.g., with the display inclined upwardly, and with a display edge oriented substantially horizontally), the device switches to a display mode—presenting information derived from the earlier-captured dermatologic imagery. The device thus switches automatically between data collection and data presentation modes, based on pose and motion. A great variety of other features and arrangements are also detailed.

Abstract: Computer-aided dermatological analysis requires accurate color data. Color accuracy can be improved by compensating captured imagery based on reference color data. In one particular arrangement, reference color data is acquired from blood. In another arrangement, imagery captured from a banknote is used as reference data. A great variety of other features and arrangements are also detailed.

Abstract: Reference imagery of dermatological conditions is compiled in a crowd-sourced database (contributed by clinicians and/or the lay public), together with associated diagnosis information. A user later submits a query image to the system (e.g., captured with a smartphone). Image-based derivatives for the query image are determined (e.g., color histograms, FFT-based metrics, etc.), and are compared against similar derivatives computed from the reference imagery. This comparison identifies diseases that are not consistent with the query image, and such information is reported to the user. Depending on the size of the database, and the specificity of the data, 90% or more of candidate conditions may be effectively ruled-out, possibly sparing the user from expensive and painful biopsy procedures, and granting some peace of mind (e.g., knowledge that an emerging pattern of small lesions on a forearm is probably not caused by shingles, bedbugs, malaria or AIDS).

Abstract: Audio sounds are captured from a subject's body, e.g., using a smartphone or a worn array of microphones. Plural features are derived from the captured audio, and serve as fingerprint information. One such feature may be a time interval over which a threshold part of spectral energy in the audio is expressed. Another may be a frequency bandwidth within which a second threshold part of the spectral energy is expressed. Such fingerprint information is provided to a knowledge base that contains reference fingerprint data and associated metadata. The knowledge base matches the fingerprint with reference fingerprint data, and provides associated metadata in return—which can comprise diagnostic information related to the captured sounds. In some arrangements, an audio signal or pressure waveform stimulates the body at one location, and is sensed at another, to discern information about the intervening transmission medium. A great variety of other features and arrangements are also detailed.

Abstract: The availability of high quality imagers on smartphones and other portable devices facilitates creation of a large, crowd-sourced, image reference library that depicts skin rashes and other dermatological conditions. Some of the images are uploaded with, or later annotated with, associated diagnoses or other information (e.g., “this rash went away when I stopped drinking milk”). A user uploads a new image of an unknown skin condition to the library. Image analysis techniques are employed to identify salient similarities between features of the uploaded image, and features of images in this reference library. Given the large dataset, statistically relevant correlations emerge that identify to the user certain diagnoses that may be considered, other diagnoses that may likely be ruled-out, and/or anecdotal information about similar skin conditions from other users. Similar arrangements can employ audio and/or other physiologically-derived signals.

Abstract: The availability of high quality imagers on smartphones and other portable devices facilitates creation of a large, crowd-sourced, image reference library that depicts skin rashes and other dermatological conditions. Some of the images are uploaded with, or later annotated with, associated diagnoses or other information (e.g., “this rash went away when I stopped drinking milk”). A user uploads a new image of an unknown skin condition to the library. Image analysis techniques are employed to identify salient similarities between features of the uploaded image, and features of images in this reference library. Given the large dataset, statistically relevant correlations emerge that identify to the user certain diagnoses that may be considered, other diagnoses that may likely be ruled-out, and/or anecdotal information about similar skin conditions from other users. A great variety of other features and arrangements are also detailed.

Abstract: Digital data is optically broadcast through an environment by controllably switching the brightness or chrominance of LED solid state lamps, or of other illumination sources (e.g., television screens and backlit computer displays). This optical data channel is useful to convey cryptographic key data by which devices within the environment can authenticate themselves to a secure network. In some embodiments, the optical modulation is sensed by the camera of a smartphone. The row data output by the smartphone's camera sensor is processed to extract the modulated data signal. In some monochrome embodiments, data communication speeds far in excess of the camera's frame rate (e.g., 30/second), or even the camera's row rate (e.g., 14,400/second) are achieved. Still greater rates can be achieved by conveying different data in different chrominance channels. A great number of other features and arrangements are also detailed.

Abstract: The disclosure provides apparatus related to arranging objects (e.g., circles, dots and other shapes) in images and graphics to convey a machine-readable signal. One claim recites an apparatus including: electronic memory for storing image or graphic data; and an electronic processor programmed for: integrating a plurality of objects in stored image or graphic data, the objects being arranged in a pattern that is machine-readable, the plurality of objects being integrated in the image or graphic so that the pattern is hidden in the image or graphic through cooperation with design elements of the image or graphic; and providing a visible structure for aiding in machine-reading of the pattern. Of course, other combinations are provided and claimed as well.

Abstract: The present invention provides steganographic and digital watermarking methods and apparatus. In a first implementation, we provide methods and apparatus for steganographically conveying data in a facial image by subtly altering facial features relative to statistical norms. In a second implementation, we convey data through different patterns of a diffraction grating. In a third implementation, we convey a digital watermark orientation component by projecting the orientation component onto an object to be captured. In the case of blue-screen technology, we incorporate an orientation component into a blue-screen itself. This provides great convenience for digital animators when overlay graphics and animation. In a forth implementation, we provide an identification document including an electronic memory chip. The chip includes an image of a bearer of the identification document. The image is digitally watermarked to include information (e.g.

Abstract: In one embodiment, a first set of digital data (e.g., an image) is tested for the presence of a certain feature (e.g., a certain face), yielding one of two outcomes (e.g., not-present, or present). If the testing yields the first outcome, no additional testing is performed. If, however, the testing yields the second outcome, further testing is performed to further check this outcome. Such further testing is performed on a second set of digital data that is based on, but different from, the first set of data. Only if the original testing and the further testing both yield the same second outcome is it treated as a valid result. A variety of other features and arrangements are also detailed.

Abstract: Arrangements are detailed to aid a user in positioning a camera-equipped device (e.g., a smartphone) at a particular viewing position relative to an object being imaged. Other embodiments discern the device's viewing position, and then undertake image or other processing that is dependent on such viewpoint. A great number of other features and arrangements are also detailed.

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 apparatus and systems for encoding and decoding signals from a host signal such as audio, video or imagery. One claim recites an apparatus comprising: electronic memory for storing a media signal representing audio or video; and an electronic processor. The electronic processor is programmed for: extracting data representing at least some features of the media signal; using the extracted data as a key to select coefficients in a transform domain, the coefficients representing the media signal; and modifying selected coefficients to hide a steganographic signal in the media signal. Of course, other claims and combinations are provided as well.

Abstract: A data set is transformed to a domain in which values are robust to distortion. The values are then expanded to carry auxiliary data. To recover the data, the data set is transformed into the domain, further transformed to get a set of possibly expanded data, and then processed to extract auxiliary data from the expanded values.

Abstract: The present claims recite various steganographic and digital watermarking methods and apparatus. One claim recites a method of watermarking a representation of a physical object. The method includes: projecting a watermark orientation component onto a physical object; and using a camera or image sensor, capturing an image or video of the physical object including the watermark orientation component as projected thereon. Another claim recites an apparatus including: a light source for projecting a registration component onto a physical object; a camera or sensor for capturing an image or video of the physical object including the registration component as projected thereon; and an electronic processor programmed for encoding a message in the image or video captured by said camera or sensor. Of course, other claims and combinations are provided as well.

Abstract: A reversible watermarking program transforms a host data file into a logical storage unit for auxiliary data files by embedding the auxiliary files in the data stored in the host data file. The reversible watermark modifies host data such as an image, audio, video, or software code, to carry auxiliary data. For perceptual content such as visual or audio media, the reversible watermark can maintain a desired level of perceptual quality, effectively hiding the auxiliary data in the host data. The reversible watermark enables the original host data prior to modifications due to the embedding to be restored.