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.

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.

Determining effect of changes in parameters may include, during a time interval, rotating from setting a first parameter to a first value for a first time period, to setting the first parameter to a second value for a second time period such that the time interval includes multiple first time periods with the first parameter set to the first value sequenced with multiple second time periods with the first parameter set to the second value; obtaining, for the time interval, a first set of ratings corresponding to the first time periods and a second set of ratings corresponding to the second time periods; averaging, for the time interval, the first set of ratings to a first average rating and the second set of ratings to a second average rating; and correlating the first average rating to the first value and the second average rating to the second value.

Determining effect of changes in parameters may include, during a time interval, rotating from setting a first parameter to a first value for a first time period, to setting the first parameter to a second value for a second time period such that the time interval includes multiple first time periods with the first parameter set to the first value sequenced with multiple second time periods with the first parameter set to the second value; obtaining, for the time interval, a first set of ratings corresponding to the first time periods and a second set of ratings corresponding to the second time periods; averaging, for the time interval, the first set of ratings to a first average rating and the second set of ratings to a second average rating; and correlating the first average rating to the first value and the second average rating to the second value.

Music is blanket transmitted (for example, via satellite downlink transmission) to each customer's user station where selected music files are recorded. Customers preselect from a list of available music in advance using an interactive screen selector, and pay only for music that they choose to playback for their enjoyment. An antipiracy WID tag is woven into the recorded music so that any illegal copies therefrom may be traced to the purchase transaction. Music is transmitted on a fixed schedule or through an active scheduling process that monitors music requests from all or a subset of satellite receivers and adjusts scheduling according to demand for various CD's. Receivers store selections that are likely to be preferred by a specific customer. In those instances where weather conditions, motion of atmospheric layers or dish obstructions result in data loss, the system downloads the next transmission of the requested CD and uses both transmissions to produce a good copy. In conjunction with the blanket transmission of more popular music, an automated CD manufacturing facility may be provided to manufacture CD's that are not frequently requested and distribute them by ground transportation.

Disclosed are a method, a device and a system of generation of a modified digital media file based on encoding of a digital media file with decodable data such that the decodable data is indistinguishable through a human ear from a primary audio stream. In one embodiment, a method includes validating a user as a publisher, associating a response action to a message of the user, using a processor and a memory, generating a unique identifier through a hash function applied to the response action, encoding a digital media file with a decodable data using the unique identifier such that the decodable data is indistinguishable from a primary audio stream through a human ear, and generating a modified digital media file based on the encoding of the message with the decodable data such that the decodable data is indistinguishable from a primary audio stream through the human ear.

Disclosed are a method, a device and a system of generation of a modified digital media file based on encoding of a digital media file with decodable data such that the decodable data is indistinguishable through a human ear from a primary audio stream. In one embodiment, a method includes validating a user as a publisher, associating a response action to a message of the user, using a processor and a memory, generating a unique identifier through a hash function applied to the response action, encoding a digital media file with a decodable data using the unique identifier such that the decodable data is indistinguishable from a primary audio stream through a human ear, and generating a modified digital media file based on the encoding of the message with the decodable data such that the decodable data is indistinguishable from a primary audio stream through the human ear.

Methods and apparatus to validate a tag for media are disclosed. An example method includes obtaining first identification information extracted from a tag distributed with media presented at a presentation location, obtaining second identification information determined from at least one of a) inherent information of at least one of audio or video of the media presented at the presentation location or b) a watermark embedded in at least one of the audio or the video of the media presented at the presentation, comparing the first identification information with the second identification information, and when first identification information does not substantially match the second identification information, preventing the tag from being used to report exposure of the media.