Methods, systems, and apparatuses for presence detection are described herein. A first computing device may emit an inaudible audio signal. A second computing device may detect the inaudible audio signal. The second computing device may send an indication of detecting the inaudible audio signal. The first computing device may cause presentation of content to be modified based on the indication sent by the second computing device and a user profile associated with a user of the second computing device.

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 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, systems, and apparatuses for presence detection are described herein. A first computing device may emit an inaudible audio signal. A second computing device may detect the inaudible audio signal. The second computing device may send an indication of detecting the inaudible audio signal. The first computing device may cause presentation of content to be modified based on the indication sent by the second computing device and a user profile associated with a user of the second computing device.

Methods, systems, and apparatuses for presence detection are described herein. A first computing device may emit an inaudible audio signal. A second computing device may detect the inaudible audio signal. The second computing device may send an indication of detecting the inaudible audio signal. The first computing device may cause presentation of content to be modified based on the indication sent by the second computing device and a user profile associated with a user of the second computing device.

A broadcast receiving apparatus includes: a tuner configured to receive a transmission wave in which identification information is stored in a carrier, the carrier being modulated differently from a data carrier, a frequency band when the transmission wave is transmitted in an air being able to be identified by the identification information; and a controller. The controller is configured to identify a frequency band when the transmission wave is transmitted in the air by using the identification information contained in transmission wave received by the tuner.

A broadcast receiving apparatus includes: a tuner configured to receive a transmission wave in which identification information is stored in a carrier, the carrier being modulated differently from a data carrier, a frequency band when the transmission wave is transmitted in an air being able to be identified by the identification information; and a controller. The controller is configured to identify a frequency band when the transmission wave is transmitted in the air by using the identification information contained in transmission wave received by the tuner.

A method and apparatus for recognizing and synchronizing to in-band data at a multimedia device is provided. A content stream includes in-band data. The in-band data is processed and in-band data pattern data associated with the content stream are created. Metadata are attached to the event identification data. The event identification data are provided to multimedia devices which receive broadcasted multimedia content streams containing video programs with in-band data. The in-band data are processed and compared to the event identification data. If a match occurs, the multimedia device uses the metadata to perform specified actions.

A method and apparatus for recognizing and synchronizing to in-band data at a multimedia device is provided. A content stream includes in-band data. The in-band data is processed and in-band data pattern data associated with the content stream are created. Metadata are attached to the event identification data. The event identification data are provided to multimedia devices which receive broadcasted multimedia content streams containing video programs with in-band data. The in-band data are processed and compared to the event identification data. If a match occurs, the multimedia device uses the metadata to perform specified actions.

Methods, apparatus, systems and articles of manufacture are disclosed for associating different watermarks detected in media. An example method disclosed herein includes determining whether a first watermark detected in a media signal is represented in a watermark data structure and associating the first watermark with a first media presentation record associated with a second watermark in response to the first watermark being associated in the watermark data structure with the second watermark. The example method further includes transmitting monitoring data including the first media presentation record to an audience measurement entity.