Various systems and methods may benefit from determination of environmental signatures in recordings. For example, such signatures may aid forensic analysis and alignment of media recordings, such as alignment of audio or video recordings. A method can include extracting electric network frequency signals from an image sequence of a video recording or an audio recording. The method can also include synchronizing the video recording or the audio recording with at least one other datum based on the electric network frequency signals.

Methods, devices, and computer-program products are provided for adding data to a digital video signal in a visually imperceptible manner. For example, a region of pixels can be identified in a video frame, and one or more pixel characteristics of the region of pixels can be determined. Based on the one or more pixel characteristics of the region of pixels, at least one pixel characteristic of a subset of pixels from the region of pixels can be modified in order to encode a set of data into the region of pixels. An output frame can be provided that includes the modified at least one pixel characteristics for the subset of pixels.

A data-bearing image (391) is created from a carrier image (371). The carrier image (371) is scaled to produce a scaled image. A clustered-dot halftone screen is applied to the scaled image to produce a halftone image. A resulting number of cells in the halftone image conforms to a cell count (372) that includes a horizontal cell value and a vertical cell value. Payload data is encoded into the halftone image to produce a data-bearing halftone image, including shifting pixel clusters within cells of the halftone image that include pixel clusters.

A device to apply a digital fingerprint to a digital signal comprises a means of intercepting or acquiring a signal, a storage element and a processor for executing computer implemented program code components in the storage element to effect the methods. The methods include transforming a plurality of signal samples onto a discrete orthonormal basis and ranking the transformed samples according to their magnitude. The n largest principal components of the ranked transformed samples are optionally permuted to generate a re-ordered set of principal components, which are then altered by a marking angle. The marked principal components and unmarked non-principal components are converted and combined and applying an inverse of the transform function to the combined principal and non-principal components to generate a fingerprinted digital signal. Methods to prepare the signal for marking, recover the digital fingerprint and verify the distributor and/or recipients of the signal are also disclosed.

A device to apply a digital fingerprint to a digital signal comprises a means of intercepting or acquiring a signal, a storage element and a processor for executing computer implemented program code components in the storage element to effect the methods. The methods include transforming a plurality of signal samples onto a discrete orthonormal basis and ranking the transformed samples according to their magnitude. The n largest principal components of the ranked transformed samples are optionally permuted to generate a re-ordered set of principal components, which are then altered by a marking angle. The marked principal components and unmarked non-principal components are converted and combined and applying an inverse of the transform function to the combined principal and non-principal components to generate a fingerprinted digital signal. Methods to prepare the signal for marking, recover the digital fingerprint and verify the distributor and/or recipients of the signal are also disclosed.

A system and method for embedding digital audio watermarks in audio source information based at least upon identified video content are described. An audio/video processing system receives audiovisual data. A video content analyzer within the system analyzes video source information of the audiovisual data, determines video content depicted by data in the video source information, and generates an indication of the video content. An audio watermark embedder of the system receives the indication, and based at least in part on the indication, adjusts watermark embedding parameters used for embedding the audio watermark in the audio source information.

A method and apparatus for secure transfer of previously broadcasted content enables the secure transfer of previously broadcasted content between DVRs on a computer network.

A method and apparatus for a digital video recorder (DVR) video editing system provides a user interface and video editing environment for content stored on a DVR's storage device. A visual progress indicator is displayed over the program content that the user has selected to edit. The user moves a position indicator within a cache bar in the visual progress indicator that indicates how much of the program content has been stored on the storage device. The user can delete sections of the program content. The user can also add other recorded program content into the program content. The deleted sections and added content are highlighted in the cache bar by colors that are different from the normal color used for the cache bar.

A method, apparatus, article of manufacture, and a memory structure for inserting a watermark in a media program is described. In an exemplary embodiment, the method comprises the steps of receiving data comprising the media program in the receiver disposed at a subscriber station, generating a watermark, the watermark generated at least in part according to a secure data processor-unique identifier irreversibly stored in the secure data processor, processing the received data to reproduce the media program, and inserting portions of the generated watermark in the reproduced media program at locations determined at least in part according to the secure data processor-unique identifier to produce a watermarked media program provided for display.

A method and apparatus for secure transfer and playback of multimedia content enables the secure transfer of multimedia content from a digital video recorder (DVR) to a personal computer (PC) and further to a handheld device. A DVR determines which devices on a Local Area Network (LAN) are authorized to share and/or retrieve content from the DVR. The DVR receives a connection request from a PC on the LAN, authorizes the connection request and establishes a secure connection between the DVR and the PC. Once the secure connection is established, the DVR receives a request for multimedia content from the PC, prepares the multimedia content for transfer and transfers the multimedia content to the PC.