Methods and apparatus to audio watermarking and watermark detection and extracted are described herein. An example method includes receiving a media content signal, sampling the media content signal to generate samples, storing the samples in a buffer, determining a first sequence of samples in the buffer, determining a second sequence of samples in the buffer, wherein the second sequence of samples is of substantially equal length as the first sequence of samples, calculating an average of the first sequence of samples and the second sequence of samples to generate an average sequence of samples, extracting an identifier from the average sequence of samples, and storing the identifier in a tangible memory.

Methods and apparatus to determine a state of a media presentation device are disclosed. Example disclosed methods include generating a first set of weighted coefficients based on first audio received by first and second microphones at a first time. Example disclosed methods include generating a second set of weighted coefficients based on second audio received by the first and second microphones at a second time after the first time. Example disclosed methods include comparing the first set of coefficients and the second set of coefficients to generate a similarity value. Example disclosed methods include, when the similarity value satisfies a threshold, determining that the media presentation device is in a first state. Example disclosed methods include, when the similarity value does not satisfy the threshold, determining that the media presentation device is in a second state.

Methods, apparatus, systems and articles of manufacture to perform audio sensor selection in an audience metering device are disclosed. An example apparatus includes at least two audio sensors to receive audio at an audience metering device and a selection tester to identify a plurality of audio sensor configurations supported by the audience metering device, the plurality of audio sensor configurations identifying respective gain values to be applied to the plurality of audio sensors. The selection tester is further to select one of the first one of the audio sensor configurations or the second one of the audio sensor configurations based on a comparison of a first quality metric and a second quality metric. The example apparatus further includes a media identifier to identify audio received at the audience metering device using the selected one of the audio sensor configurations.

The present disclosure describes an efficient computer-implemented near-field communication system and method based on broadcasting audio signals for dynamically providing context-related additional content to a mobile device. In embodiments of the present invention, the additional content is mapped to specific audio watermarks and/or triggering commands which are encoded together into a digital signal. Based on continuously scanning the received background noise, an exactly defined frequency range and volume is dynamically selected for broadcasting the signal. Hence, the encoded digital signal is further modulated into an audio signal in the exactly defined frequency range. In embodiments of the present invention, the selected exactly defined frequency range for transmitting the audio signal may preferably be located in the ultrasound and/or infrasound frequency range. In case of transmitting infrasound signals, gyrosensors of the mobile device may be employed as audio signal receivers in embodiments of the present invention. Moreover, in further embodiments of the present invention, audio signal receiver of a mobile device such as gyrosensors or microphones may be switched on by transmitting a command via a wireless network such as Wifi or Bluetooth. Also the information about the selected frequency range and volume for broadcasting the audio signal may be provided to the mobile device via a wireless network in embodiments of the present invention. In response, an audio signal receiver of the mobile device may be tuned to the selected frequency range. The received audio signal is further processed on the mobile device so that the context-related additional content may be displayed and/or rendered.

A method of processing supplementary content in a digital receiving apparatus, includes connecting to an external device being different from a broadcaster; receiving uncompressed audio/video (A/V) content from the external device being different from the broadcaster; extracting audio watermark from the uncompressed A/V content, wherein the audio watermark includes domain type information, time information and event flag; constructing a first uniform resource locator (URL) based on the audio watermark, transmitting a request to a remote server based on the first URL; receiving a second URL for the supplementary content from the remote server, and presenting the supplementary content based on the second URL.

Methods, apparatus, systems and articles of manufacture (e.g., physical storage media) to implement flexible commercial monitoring for television audience measurement are disclosed. Example television audience measurement systems disclosed herein include a flexible commercial detector to detect whether a first watermark decoded from a television program broadcast signal is a bridge watermark that indicates a portion of the television broadcast signal including the bridge watermark is associated with a flexible commercial insertion event, the flexible commercial insertion event corresponding to insertion of a flexible commercial in the portion of the television broadcast signal. Disclosed example television audience measurement systems also include a commercial metric calculator to credit audience exposure associated with the portion of the television broadcast signal to a flexible commercial crediting metric in response to a determination that the first watermark is the bridge watermark.

Disclosed example people monitoring methods include detecting a first watermark in a first audio signal obtained from an acoustic sensor, the first watermark identifying media presented by a monitored media device, determining whether a second watermark, different from the first watermark, is embedded in the first audio signal obtained from the acoustic sensor, the second watermark identifying at least one of a mobile device or a user of the mobile device, classifying the second watermark as a media watermark or a people monitoring watermark based on a characteristic of the second watermark, and when the second watermark is determined to be embedded in the first audio signal, reporting at least one of the second watermark or information decoded from the second watermark to identify at least one of the mobile device or the user of the mobile device as being exposed to the media presented by the monitored media device.

The present technology relates to a transmission apparatus, a transmission method, a reception apparatus, and a reception method that make it possible to detect a watermark more easily. The transmission apparatus includes a generation section and a transmission section. The generation section generates watermark information for detecting a watermark. The transmission section transmits a broadcast signal including the watermark and the watermark information. When the transmission apparatus is provided, it enables the reception apparatus at a receiving end to detect the watermark more easily. The present technology is applicable, for example, to a transmission system including the transmission apparatus and the reception apparatus.

A method, non-transitory computer-readable storage medium, and reception apparatus for extracting metadata, and an information providing apparatus for providing the metadata. The method for extracting metadata includes processing, by circuitry of the reception apparatus, content that includes the metadata embedded therein. The metadata is embedded as a watermark in a first portion of a video frame of the content. The circuitry determines symbol values of the watermark from the video frame based on luminance values in pixels of the first portion of the video frame of the content to extract the metadata. At least one of the luminance values is less than 16.

Methods, apparatus, systems and articles of manufacture are disclosed selectively generating and storing hashed reference signatures. An example method disclosed herein determining whether watermark coverage of a first media segment satisfies a dropout constraint, the first media segment corresponding to a first monitoring time interval of a media source feed and, when the watermark coverage of the first media segment does not satisfy the dropout constraint hashing first media signatures associated with the first media segment to generate corresponding first hashed signatures and generating first reference data for the first media segment, the first reference data including the first hashed signatures and the first media signatures. The example method further includes, when the watermark coverage of the first media segment satisfies the dropout constraint, generating second reference data for the first media segment, the second reference data including the first media signatures.