Abstract: Methods, apparatus, systems and articles of manufacture are disclosed to use station identification to enable confirmation of exposure to live media. Example apparatus disclosed herein include a watermark data segmenter to determine a media identifier conveyed by a watermark, a detection time determiner to determine a time at which a media meter detected the watermark from a media presentation by a media device, a reference identifier to query a library of reference signatures for a reference signature associated with the media identifier of the watermark and associated with a reference timestamp corresponding to the time at which the media meter detected the watermark, and a viewing type determiner to determine whether the media presentation is live or time-shifted based on whether a result of the query indicates the reference signature does not exist in the library of reference signatures.

Abstract: A method and system for adding overtly human-perceptible supplemental audio content into a media stream to help mask audio effects of an audio watermark in the media stream. A method involves receiving a media stream that defines a sequence of audio content presentable by a content presentation device, modifying the media stream to produce a modified media stream that defines the sequence of audio content, and outputting the modified media stream for presentation by the content presentation device. The modified media stream includes an audio watermark that is machine-detectable to trigger an interactive event. Further, the act of modifying the media stream involves adding into the media stream supplemental audio content coincident with the audio watermark, to help mask the audio watermark in the modified media stream during presentation of the modified media stream by the content presentation device.

Abstract: Methods and apparatus are disclosed for supplementing partially readable and/or inaccurate codes. An example apparatus includes a watermark analyzer to select a first watermark and a second watermark decoded from media; a comparator to compare a first decoded timestamp of the first watermark to a second decoded timestamp of the second watermark; and a timestamp adjuster to adjust the second decoded timestamp based on the first decoded timestamp of the second watermark when at least a threshold number of symbols of the second decoded timestamp match corresponding symbols of the first decoded timestamp.

Abstract: Methods, apparatus, systems and articles of manufacture are disclosed to use station identification to enable confirmation of exposure to live media. Example apparatus disclosed herein include a watermark data segmenter to determine a media identifier conveyed by a watermark, a detection time determiner to determine a time at which a media meter detected the watermark from a media presentation by a media device, a reference identifier to query a library of reference signatures for a reference signature associated with the media identifier of the watermark and associated with a reference timestamp corresponding to the time at which the media meter detected the watermark, and a viewing type determiner to determine whether the media presentation is live or time-shifted based on whether a result of the query indicates the reference signature does not exist in the library of reference signatures.

Abstract: Methods, apparatus, systems, and articles of manufacture to improve watermark detection in acoustic environments are disclosed. An example apparatus includes at least one memory, instructions in the apparatus, and processor circuitry to execute and/or instantiate the instructions to encode a first symbol in a media file at a first symbol position on a first encoding layer of a multilayered watermark, and encode a second symbol in the media file at a second symbol position on a second encoding layer of the multilayered watermark, the first encoding layer and the second encoding layer including a plurality of symbol positions, one or more of the plurality of the symbol positions on at least one of the first encoding layer or the second encoding layer to be empty.

Abstract: Apparatus, systems, articles of manufacture, and methods to identify and credit media using ratios of media characteristics are disclosed herein. Example apparatus to identify media include at least one memory, instructions, and at least one processor to execute the instructions to: determine a first ratio based on a first time interval and a second time interval of a monitored media signal; determine a second ratio based on the second time interval and a third time interval of the monitored media signal; generate a first ratio signature based on the first and second ratios; and initiate transmission of the first ratio signature to a recipient that is to compare the first signature with a second ratio signature to identify the media.

Abstract: Display device ON/OFF detection methods and apparatus are disclosed. Example display activity detectors disclosed herein are to extract regions from respective ones of captured video frames, the regions corresponding to a depiction of a display of a monitored media device Disclosed example display activity detectors are also to compute a distance metric that is to represent an amount a first one of the regions of a first one of the captured video frames differs from a corresponding second one of the regions of a second one of the captured video frames. Disclosed example display activity detectors are further to compare the distance metric to a threshold to determine whether the monitored media device is ON or OFF.

Abstract: An example symbol-based watermark detection method disclosed herein includes, in response to a comparison of a first count of occurrences of a first potential symbol value corresponding to a first symbol within a watermark and a second count of occurrences of a second potential symbol value corresponding to the first symbol, (i) determining a first accumulated signal to noise ratio value corresponding to the occurrences of the first potential symbol value, (ii) determining a second accumulated signal to noise ratio value corresponding to the occurrences of the second potential symbol value, and (iii) selecting one of the first or the second potential symbol value having a greatest accumulated signal to noise ratio value as a likely symbol value for the first symbol. The example method also includes concatenating the likely symbol value with other likely symbol values corresponding to other symbols of the watermark to detect the watermark.

Abstract: Examples are disclosed to perform signature matching using noise cancellation models to achieve consensus. Example apparatus disclosed herein include a signature matcher to compare a first stream of monitored media signatures to streams of reference signatures representative of corresponding reference media to determine a first signature match, and compare a second stream of monitored media signatures to the streams of reference signatures to determine a second signature match; a match selector to use at least one the first signature match or the second signature match to identify a first one of the reference media corresponding to the monitored media data; and a creditor interface to output identification data for the first one of the reference media identified with the at least one the first signature match or the second signature match, the identification data to be used to credit a media exposure corresponding to the monitored media.

Abstract: Methods and apparatus are disclosed for supplementing partially readable and/or inaccurate codes. An example apparatus includes a watermark analyzer to select a first watermark and a second watermark decoded from media; a comparator to compare a first decoded timestamp of the first watermark to a second decoded timestamp of the second watermark; and a timestamp adjuster to adjust the second decoded timestamp based on the first decoded timestamp of the second watermark when at least a threshold number of symbols of the second decoded timestamp match corresponding symbols of the first decoded timestamp.

Abstract: Methods and apparatus to obtain exposure data for media exposure environment(s) are disclosed. An example apparatus disclosed herein includes processor circuitry to determine audience identification information and content identifying data.

Abstract: 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.

Abstract: Methods, apparatus, systems and articles of manufacture to update audio sensor configuration are disclosed.

Abstract: A method and system for adding overtly human-perceptible supplemental audio content into a media stream to help mask audio effects of an audio watermark in the media stream. A method involves receiving a media stream that defines a sequence of audio content presentable by a content presentation device, modifying the media stream to produce a modified media stream that defines the sequence of audio content, and outputting the modified media stream for presentation by the content presentation device. The modified media stream includes an audio watermark that is machine-detectable to trigger an interactive event. Further, the act of modifying the media stream involves adding into the media stream supplemental audio content coincident with the audio watermark, to help mask the audio watermark in the modified media stream during presentation of the modified media stream by the content presentation device.

Abstract: Methods and apparatus to obtain exposure data for media exposure environment(s) are disclosed. An example apparatus disclosed herein includes processor circuitry to determine audience identification information and content identifying data.

Abstract: Methods, apparatus, systems, and articles of manufacture to fingerprint an audio signal. An example apparatus disclosed herein includes an audio segmenter to divide an audio signal into a plurality of audio segments, a bin normalizer to normalize the second audio segment to thereby create a first normalized audio segment, a subfingerprint generator to generate a first subfingerprint from the first normalized audio segment, the first subfingerprint including a first portion corresponding to a location of an energy extremum in the normalized second audio segment, a portion strength evaluator to determine a likelihood of the first portion to change, and a portion replacer to, in response to determining the likelihood does not satisfy a threshold, replace the first portion with a second portion to thereby generate a second subfingerprint.

Abstract: Methods and apparatus to capture images are disclosed. An example apparatus disclosed herein includes an image sensor to observe a first image of a face, and a logic circuit to determine whether the face in the first image is in a first orientation with respect to the image sensor, and when the face in the first image is in the first orientation: trigger the image sensor to capture a second image of the face, and perform a facial recognition process on the second image, but not on the first image.

Abstract: Methods, apparatus, systems and articles of manufacture are disclosed for wear noise audio signature suppression. An example method disclosed herein includes generating an audio signature based on a media audio signal during a first time period, collecting acceleration data during the first time period, determining whether the acceleration data corresponds to wear noise having occurred during the first time period, and in response to determining the acceleration data corresponds to wear noise during the first time period, inhibiting transmission of the audio signature to a central facility.

Abstract: A method and system for adding overtly human-perceptible supplemental audio content into a media stream to help mask audio effects of an audio watermark in the media stream. A method involves receiving a media stream that defines a sequence of audio content presentable by a content presentation device, modifying the media stream to produce a modified media stream that defines the sequence of audio content, and outputting the modified media stream for presentation by the content presentation device. The modified media stream includes an audio watermark that is machine-detectable to trigger an interactive event. Further, the act of modifying the media stream involves adding into the media stream supplemental audio content coincident with the audio watermark, to help mask the audio watermark in the modified media stream during presentation of the modified media stream by the content presentation device.

Abstract: 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.