Abstract: Methods, apparatus, systems, and articles of manufacture to perform speed-enhanced playback of recorded media are disclosed. Example apparatus to playback media disclosed herein comprise at least one memory, machine-readable instructions, and processor circuitry to execute the machine-readable instructions to parse an audio frame included in the media to determine a number of skip bytes included in the audio frame, compare the number of skip bytes to a threshold, associate the audio frame with a plurality of candidate frames identified in the media when the number of skip bytes satisfies the threshold, and calculate a speed-enhanced playback rate for the media based on the plurality of candidate frames identified in the media.

Abstract: Methods and apparatus to perform audio watermarking and watermark detection and extraction are disclosed. Example apparatus disclosed herein are to select frequency components to be used to represent a code, different sets of frequency components to represent respectively different information, respective ones of the frequency components in the sets of frequency components located in respective code bands, there being multiple code bands and spacing between adjacent code bands being equal to or less than the spacing between adjacent frequency components in the code bands. Disclosed example apparatus are also to synthesize the frequency components to be used to represent the code, combine the synthesized frequency components with an audio block of an audio signal, and output the audio signal and a video signal associated with the audio signal.

Abstract: Example apparatus disclosed herein are to identify encoded information present in audio obtained for a time period. Disclosed example apparatus are also to generate a signature of the audio for comparison with signatures of reference media. Disclosed example apparatus are also to generate a first determination that a media presentation device was in an off state during a first portion of the time period based on a gain level applied by an automatic gain controller to collect the audio. Disclosed example apparatus are also to override the first determination that the media presentation device was in the off state during the first portion of the time period with a second determination that the media presentation device was in an on state during the first portion of the time period, the second determination based on at least one of the encoded information or the signature.

Abstract: Example methods disclosed herein include accessing a secondary content schedule based on one or more watermarks detected in primary media content, the secondary content schedule to identify (i) one or more secondary content items and (ii) one or more first time values associated with the one or more secondary content items. Disclosed example methods also include comparing the one or more first time values associated with the one or more secondary content items in the secondary content schedule to second time values provided by a clock to determine whether to present a first one of the one or more secondary content items, the second time values based on a timestamp associated with the one or more watermarks detected in the primary media content. Disclosed example methods further include causing a media presentation device to display the first one of the secondary content items according to the secondary content schedule.

Abstract: 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.

Abstract: Methods, apparatus, systems, and articles of manufacture to perform speed-enhanced playback of recorded media are disclosed. Example apparatus to playback media disclosed herein comprise at least one memory, machine-readable instructions, and processor circuitry to execute the machine-readable instructions to parse an audio frame included in the media to determine a number of skip bytes included in the audio frame, compare the number of skip bytes to a threshold, associate the audio frame with a plurality of candidate frames identified in the media when the number of skip bytes satisfies the threshold, and calculate a speed-enhanced playback rate for the media based on the plurality of candidate frames identified in the media.

Abstract: Methods and apparatus for determining increasing robustness of media signatures are disclosed. An example apparatus disclosed herein is to select to at least one of (A) boost a first characteristic of a media signal at a first time or (B) attenuate a second characteristic of the media signal at a second time based on an effect of the at least one of the boost of the first characteristic or the attenuation of the second characteristic on a difference between a third characteristic of the media signal at a third time and a fourth characteristic of the media signal at a fourth time. The disclosed example apparatus is also to perform the selected one of (A) the boost of the first characteristic of the media signal at the first time or (B) the attenuation of the second characteristic of the media signal at the second time to enhance the media signal.

Abstract: Methods, apparatus, systems and articles of manufacture are disclosed for media crediting and, more particularly, methods and apparatus of media device detection for minimally invasive media meters. An example apparatus disclosed herein to detect media devices presenting media includes means for generating a cluster of media locations from a reference population of media locations based on media identifying information received from a presentation of media at an unidentified media device at a first media location, means for determining media devices available at the media locations in the cluster of media locations, means for identifying the unidentified media device based on (1) the media devices available at the media locations in the cluster of media locations and (2) an identity of a media device determined to be available in a majority of media locations in the cluster of media locations.

Abstract: Example methods and apparatus to verify presentation of media content are disclosed. A disclosed example apparatus for generating media presentation information includes a comparator to periodically output a value indicative of whether media selected via a set-top box is presented at a media presentation location by comparing a first audio signal associated with the media to ambient audio received in the media presentation location via an audio system associated with a media presentation device. The example apparatus also includes a privacy protector to facilitate operation of the comparator by periodically preventing the comparator from receiving of the ambient audio. The example apparatus also includes a metering module to record presentation of the media based on the output.

Abstract: 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.

Abstract: Example apparatus disclosed herein are to determine a location of a portable device based on location data collected by the portable device, determine whether a person is within a threshold distance of the portable device based on proximity data collected by the portable device, and, when the person is determined to be within the threshold distance of the portable device: (i) infer at least one of a presence or an absence of the person in a media exposure environment based on the location of the portable device, (ii) determine a confidence level that the person corresponds to a member of the panelist household, and (iii) determine an accuracy of presence information collected by a people meter based on the confidence level and the inference of the at least one of the presence or the absence of the person, the people meter different than the portable device.

Abstract: Example methods and apparatus to verify presentation of media content are disclosed. A disclosed example apparatus for generating media presentation information includes a comparator to periodically output a value indicative of whether media selected via a set-top box is presented at a media presentation location by comparing a first audio signal associated with the media to ambient audio received in the media presentation location via an audio system associated with a media presentation device. The example apparatus also includes a privacy protector to facilitate operation of the comparator by periodically preventing the comparator from receiving of the ambient audio. The example apparatus also includes a metering module to record presentation of the media based on the output.

Abstract: Methods, apparatus, systems and articles of manufacture (e.g., physical storage media) to detect media watermarks in magnetic field data are disclosed herein. Example media monitors disclosed herein include a magnetic field estimator to determine first magnetic field data, the magnetic field estimator in communication with a magnetometer. Disclosed example media monitors also include a correlator to correlate the first magnitude field data with a reference sequence to determine second magnetic field data. Disclosed example media monitors further include a watermark decoder to process the second magnetic field data to detect an audio watermark encoded in an audio signal.

Abstract: Example apparatus disclosed herein are to identify encoded information present in audio obtained for a time period. Disclosed example apparatus are also to generate a signature of the audio for comparison with signatures of reference media. Disclosed example apparatus are also to generate a first determination that a media presentation device was in an off state during a first portion of the time period based on a gain level applied by an automatic gain controller to collect the audio. Disclosed example apparatus are also to override the first determination that the media presentation device was in the off state during the first portion of the time period with a second determination that the media presentation device was in an on state during the first portion of the time period, the second determination based on at least one of the encoded information or the signature.

Abstract: Methods, apparatus, systems and articles of manufacture are disclosed for media crediting and, more particularly, methods and apparatus of media device detection for minimally invasive media meters. An example apparatus disclosed herein to detect media devices presenting media includes means for generating a cluster of media locations from a reference population of media locations based on media identifying information received from a presentation of media at an unidentified media device at a first media location, means for determining media devices available at the media locations in the cluster of media locations, means for identifying the unidentified media device based on (1) the media devices available at the media locations in the cluster of media locations and (2) an identity of a media device determined to be available in a majority of media locations in the cluster of media locations, and means for generating a report on the identity of the unidentified media device.

Abstract: Methods, apparatus and articles of manufacture (e.g., computer readable media) to detect watermark modifications are disclosed. Example apparatus disclosed herein include means for encoding a first watermark in a first media signal obtained from an output of a media device to obtain a second media signal encoded with the first watermark and a second watermark, the second watermark already encoded in the first media signal obtained from the output of the media device. Disclosed example apparatus also include means for decoding the first watermark and the second watermark from the second media signal to determine a first metric corresponding to the first watermark and a second metric corresponding to the second watermark. Disclosed example apparatus further include means for outputting, based on the first metric and the second metric, an indication of whether the second watermark has been modified.

Abstract: Methods, apparatus, systems and articles of manufacture are disclosed for scalable architectures for reference signature matching and updating. An example method for scalable architectures for reference signature matching and updating includes accessing site signatures to be compared to reference signatures from a first group of media sources. Determining if a first reference node is an owner of a first one of the site signatures. Comparing a neighborhood of site signatures including the first site signature to reference signatures in a first subset of reference signatures when the first reference node is the owner of the first site signature, the first subset of references signatures stored in a first memory partition associated with the first reference node. Not comparing site signature to reference signatures when the first reference node is not the owner of the first one of the site signatures.

Abstract: Example apparatus disclosed herein are to determine a location of a portable device based on location data collected by the portable device, determine whether a person is within a threshold distance of the portable device based on proximity data collected by the portable device, and, when the person is determined to be within the threshold distance of the portable device: (i) infer at least one of a presence or an absence of the person in a media exposure environment based on the location of the portable device, (ii) determine a confidence level that the person corresponds to a member of the panelist household, and (iii) determine an accuracy of presence information collected by a people meter based on the confidence level and the inference of the at least one of the presence or the absence of the person, the people meter different than the portable device.

Abstract: 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.

Abstract: Example apparatus disclosed herein are to obtain a first hash key, a second hash key and a third hash key representative of first reference media in response to a first query of a first table, the second hash key associated with a second time preceding a first time associated with the first hash key, the third hash key associated with a third time following the first time associated with the first hash key. Disclosed example apparatus are also to prequalify the first hash key as a candidate for subsequent signature processing associated with a first site signature in response to a determination that the second hash key corresponds to a second site signature preceding the first site signature in time and that the third hash key corresponds to a third site signature following the first site signature in time.