Methods and systems for tracking image senders using client devices are described herein. A computing system may receive an image containing a first watermark vector corresponding to a user account of an image sender. The computing system may convert the image to a frequency domain image that contains the first watermark vector. From the frequency domain image, the computing system may identify the first watermark vector. The computing system may compare the first watermark vector to each of a plurality of stored watermark vectors, each corresponding to a known user account, to determine a probability of a match. The computing system may determine the user account of the sender of the image by determining which of the plurality of stored watermark vectors has a highest probability of a match, and may send, to a workplace administrator platform, an indication of the user account.

Disclosed in this application are a method for embedding a watermark in video data and apparatus, a method for extracting a watermark in video data and apparatus, a device, and a storage medium. The method for embedding the watermark includes: acquiring a target image frame in video data; performing time-frequency transformation on the target image frame to obtain target frequency domain data, the target frequency domain data comprising a matrix formed by frequency domain coefficients; changing the frequency domain coefficients in the target frequency domain data according to watermark data to obtain watermarked frequency domain data; performing inverse time-frequency transformation on the watermarked frequency domain data to obtain a watermarked image frame; and synthesizing watermarked video data according to the watermarked image frame.

The present invention relate generally to signal encoding and decoding. One claim recites a method comprising: obtaining color image data or color video data, the color image data or color video data comprising an encoded signal pattern, the encoded signal pattern aiding detection of an encoded message, the pattern comprising first frequency components and second frequency components, the color image data or color video data comprising first color data and second color data, in which the first color data comprises the first frequency components encoded therein, and the second color data comprises the second frequency components encoded therein; combining the first color data and the second color data, said combining yielding combined color data; utilizing one or more processors or electronic processing circuitry, detecting the encoded signal pattern from the combined color data, said detecting yielding rotation and scale information; and using the rotation and scale information to detect the encoded message from the combined color data. Of course, other combinations and claims are provided too.

A digital watermark analysis apparatus, comprising an image capturing unit for capturing a printed product where additional information is embedded by superimposing a pattern on an image to acquire a captured image, a calculation unit for calculating a spatial frequency characteristic of each small area in the captured image, a specifying unit for specifying an embedded signal strength and an embedding position of the additional information, a decision unit for deciding, based on the embedding position information and the embedded signal strength information, a position in the captured image of a marker detection area for detecting a marker as a reference position for acquiring the additional information, and an acquisition unit for detecting a marker in the marker detection area and acquiring the additional information in the captured image with reference to the detected marker.

This application relates to an image processing method and apparatus, a storage medium, and a computer device. The method includes: obtaining a frequency domain mark image, the frequency domain mark image being obtained by performing frequency domain transformation on a spatial domain mark image; obtaining a transparency parameter configured corresponding to the frequency domain mark image; obtaining target page data; and performing layer superimposition rendering of the frequency domain mark image and the target page data according to the transparency parameter. The solution provided in this application can effectively protect target page data.

A method and apparatus for embedding a digital watermark in image content that is not visible to the human eye is performed on single-sensor digital camera images (often called ‘raw’ images) from a pixel-array. The raw image is transformed to generate preprocessed image coefficients, a watermark message is encrypted using a first key; the encrypted watermark message is randomized using a second key to form a watermark; and the watermark is embedded in randomly selected preprocessed image coefficients.

A system, method and computer program product for protecting a deep neural network image classifier against receiving perturbed images. A plurality of watermark bits are embedded into an original digital image intended for the deep neural network image classifier. The watermarked image is transmitted through a potentially adversarial environment. A potentially perturbed image intended for the deep neural network image classifier is received from the potentially adversarial environment. The potentially perturbed image is determined to be an adversely modified or benign image by determining whether the potentially perturbed image includes a plurality of embedded bits matching the plurality of watermark bits embedded into the original digital image. The potentially perturbed image is prevented from being provided to the deep neural network image classifier in response to determining that the potentially perturbed image is the adversely modified image.

A system, device and method for fingerprint authentication using a watermarked digital image is provided. A device includes a display device including a touch screen configured to detect fingerprints; and, a controller. The controller: generates, at the display device, an image that includes, in one or more given areas, image-embedded fingerprint information; detects, at one or more portions of the touch screen respectively corresponding to the one or more given areas, user-fingerprint information representing a fingerprint; implements a comparison between the user-fingerprint information and the image-embedded fingerprint information; and when the comparison between the user-fingerprint information and the image-embedded fingerprint information is successful, implement an access process.

Systems and methods are described for obfuscating variants of content segments. Variants of content segments can be used to encode an identifying sequence in a transmission of content. The variants of the content segments can each include one or more marked frames and one or more unmarked frames. Variations can be introduced into the unmarked frames for each of the variants of the content segments.

In computer vision systems that need to decode machine-readable indicia from captured imagery, it is critical to select imaging parameters (e.g., exposure interval, exposure aperture, camera gain, intensity and duration of supplemental illumination) that best allow detection of subtle features from imagery. In illustrative embodiments, a Shannon entropy metric or a KL divergence metric is used to guide selection of an optimal set of imaging parameters. In accordance with other aspects of the technology, different strategies identify which spatial locations within captured imagery should be successively examined for machine readable indicia, in order to have a greatest likelihood of success, within a smallest interval of time. A great variety of other features and arrangements are also detailed.