Abstract: Methods, apparatus, systems and articles of manufacture are disclosed to perform symbol-based watermark detection. An example method includes, in response to determining that a first rate of occurrence of a first potential symbol equals a second rate of occurrence of a second potential symbol, a first accumulated signal to noise ratio value corresponding to occurrences of the first potential symbol value is determined. A second accumulated signal to noise ratio value corresponding to occurrences of the second potential symbol value is determined. One of the first potential symbol value or the second potential symbol value having a greatest accumulated signal to noise ratio value as the likely symbol value is selected. The likely symbol value is concatenated with other likely symbol values corresponding to other symbols of the watermark to detect the watermark.

Abstract: Display device ON/OFF detection methods and apparatus are disclosed. Example metering apparatus disclosed herein include first means for sensing an audio signal output from a media device. Disclosed example metering apparatus also include second means for performing audio code detection to detect audio codes in the audio signal, and third means for determining an audio gain level applied to the audio signal. Disclosed example metering apparatus further include fourth means for determining whether the media device is ON or OFF based on the audio gain level applied to the audio signal and whether a valid audio code is detected in the audio signal.

Abstract: Methods and apparatus to identify and credit media using ratios of media characteristics are disclosed herein. Example methods and apparatus determine a first ratio based on a first combination of time intervals of a monitored media signature, the monitored media signature including a plurality of time intervals, respective ones of the time intervals being between respective adjacent characteristics identified in the media, determine a second ratio based on a second combination of time intervals of the monitored media signature, generate a monitored media ratio signature based on the first and second ratios, and compare the monitored media ratio signature with a reference ratio signature to identify the media.

Abstract: Example metering apparatus and related methods are disclosed. An example apparatus disclosed herein includes a housing having a display area, The apparatus includes at least one of a first stencil or a second stencil to be removably positionable in the display area of the housing. The first stencil has indicia oriented in a landscape orientation and the second stencil has indicia oriented in a portrait orientation. The at least one of the first stencil or the second stencil is to be positioned in the display area of the housing such that the indicia of the at least one of the first stencil or the second stencil is in an upright orientation relative to the housing. The apparatus includes a cover removably coupled to the housing to enable access to the display area.

Abstract: Display device ON/OFF detection methods and apparatus are disclosed. Example methods disclosed herein include measuring, with a first sensor, a first temperature value associated with the media device. Example methods disclosed herein also include measuring, with a second sensor, a second temperature value corresponding to an ambient temperature in an environment including the media device. Example methods disclosed herein further include comparing the first temperature value to the second temperature value to make a first determination indicating whether the media device is ON or OFF.

Abstract: Methods and apparatus to operate a mobile phone are disclosed. An example mobile phone disclosed herein includes an illumination source and an image sensor to capture a first image of a face. The disclosed example mobile phone also includes a logic circuit to determine whether the face in the first image is in a first orientation with respect to the image sensor. When the face in the first image is in the first orientation, the logic circuit is to trigger the image sensor to capture a second image and perform a facial recognition process on the second image, but not on the first image.

Abstract: Example metering apparatus and related methods are disclosed. An example apparatus disclosed herein includes a housing having a display area, The apparatus includes at least one of a first stencil or a second stencil to be removably positionable in the display area of the housing. The first stencil has indicia oriented in a landscape orientation and the second stencil has indicia oriented in a portrait orientation. The at least one of the first stencil or the second stencil is to be positioned in the display area of the housing such that the indicia of the at least one of the first stencil or the second stencil is in an upright orientation relative to the housing. The apparatus includes a cover removably coupled to the housing to enable access to the display area.

Abstract: Methods, apparatus, systems and articles of manufacture are disclosed to perform symbol-based watermark detection. An example method includes, in response to determining that a first rate of occurrence of a first potential symbol equals a second rate of occurrence of a second potential symbol, a first accumulated signal to noise ratio value corresponding to occurrences of the first potential symbol value is determined. A second accumulated signal to noise ratio value corresponding to occurrences of the second potential symbol value is determined. One of the first potential symbol value or the second potential symbol value having a greatest accumulated signal to noise ratio value as the likely symbol value is selected. The likely symbol value is concatenated with other likely symbol values corresponding to other symbols of the watermark to detect the watermark.

Abstract: Methods, apparatus, systems and articles of manufacture to perform audio sensor selection in an audience metering device are disclosed. An example method includes identifying a plurality of audio sensor configurations supported by the audience metering device. A first quality metric of a first media identifier determined from first audio received via a first one of the audio sensor configurations is computed. A second quality metric of a second media identifier determined from second audio received via a second one of the audio sensor configurations is computed. One of the first one of the audio sensor configurations or the second one of the audio sensor configurations is selected based on a comparison of the first quality metric and the second quality metric. Media monitoring is performed at the audience metering device using the selected one of the audio sensor configurations.

Abstract: Methods and apparatus to capture images are disclosed. An example method includes determining whether a face detected in a first frame captured at a first time with an image capturing device in a first illumination mode is in a first orientation with respect to the image capturing device, operating the image capturing device in a second illumination mode at a second time when the face detected in the first frame is in the first orientation, wherein an illumination source emits light while in the second illumination mode and does not emit light while in the first illumination mode, operating the image capturing device in the first illumination mode at the second time when the face detected in the first frame is not in the first orientation, and performing a facial recognition process on image data captured under the second illumination mode, but not on image data captured under the first illumination mode.

Abstract: Methods and apparatus to collect media identifying data are disclosed. An example system to monitor media includes a printed circuit board defining a sound hole, the sound hole including a cylindrical portion and a chamfered opening, the sound hole having an effective length-to-width ratio of about 1.25; a memory including machine readable instructions; and a processor to execute the instructions to process the audio data collected through the sound hole to obtain media identifying data.

Abstract: Methods and apparatus to identify and credit media using ratios of media characteristics are disclosed herein. Example methods and apparatus determine a first ratio based on a first combination of time intervals of a monitored media signature, the monitored media signature including a plurality of time intervals, respective ones of the time intervals being between respective adjacent characteristics identified in the media, determine a second ratio based on a second combination of time intervals of the monitored media signature, generate a monitored media ratio signature based on the first and second ratios, and compare the monitored media ratio signature with a reference ratio signature to identify the media.

Abstract: Methods and apparatus to capture images are disclosed. An example method includes determining whether a face detected in a first frame captured at a first time with an image capturing device in a first illumination mode is in a first orientation with respect to the image capturing device, operating the image capturing device in a second illumination mode at a second time when the face detected in the first frame is in the first orientation, wherein an illumination source emits light while in the second illumination mode and does not emit light while in the first illumination mode, operating the image capturing device in the first illumination mode at the second time when the face detected in the first frame is not in the first orientation, and performing a facial recognition process on image data captured under the second illumination mode, but not on image data captured under the first illumination mode.

Abstract: Methods and apparatus to capture images are disclosed. An example apparatus includes an image capturing device to operate in a first illumination mode or a second illumination mode; and a logic circuit to determine whether a head detected in a first frame captured at a first time is oriented such that a facial recognition process on a second frame has greater than a threshold likelihood to succeed; place the image capturing device in the first illumination mode at the second time when the head detected in the first frame is oriented such that the facial recognition process has greater than the threshold likelihood to succeed; and place the image capturing device in the second illumination mode at the second time when the head detected in the first is not oriented such that the facial recognition process has greater than the threshold likelihood to succeed.

Abstract: Methods and apparatus to detect carrying of a portable audience measurement device are disclosed herein. An example portable audience measurement device including a housing; a media detector in the housing to collect media exposure data; a hinge having an arm to rotate in response to an applied, the arm to secure the housing to an object associated with a person; a rotation sensor to detect a magnitude of rotation of the arm relative to the housing; and a detector to compare the magnitude of rotation of the arm to a threshold angle to determine whether the device is being carried by the person.

Abstract: Display device ON/OFF detection methods and apparatus are disclosed. Example methods disclosed herein include measuring, with a first sensor, a first temperature value associated with the media device. Example methods disclosed herein also include measuring, with a second sensor, a second temperature value corresponding to an ambient temperature in an environment including the media device. Example methods disclosed herein further include comparing the first temperature value to the second temperature value to make a first determination indicating whether the media device is ON or OFF.

Abstract: Display device ON/OFF detection methods and apparatus are disclosed. Example methods disclosed herein include performing audio code detection on an audio signal corresponding to an output of a presentation device. Such disclosed example methods also include determining a first result based on whether a valid audio code is detected in the audio signal, and determining a second result based on an audio gain level used to adjust the audio signal prior to performing audio code detection on the audio signal. Such disclosed example methods further include combining the first result and the second result to determine a third result indicating whether the presentation device is ON or OFF.

Abstract: Methods and apparatus to export tuning data collected in a receiving device are disclosed. An example method of collecting audience measurement data comprises collecting tuning data within a receiving device, and modulating an LED associated with the receiving device to export the collected tuning data from the receiving device.

Abstract: An example method includes determining if first media monitoring data provided by a first meter in a first location identifies a same media as second media monitoring data provided by a second meter in a second location. When the first and second media monitoring data identify the same media, the example includes determining whether spillover occurred based on a time difference between a first timestamp associated with the first media monitoring data and a second timestamp associated with the second media monitoring data. Based on an occurrence of the spillover, the first media monitoring data is stored as credited media monitoring data for the first location indicative of a media exposure to an audience at the first location, and the second media monitoring data is not stored as credited media monitoring data for the second location when the first timestamp is earlier than the second timestamp.

Abstract: Methods, apparatus, and articles of manufacture for reducing spillover in a media monitoring system are disclosed. An example method includes determining an actual frequency spectrum of the media monitored by a meter, and determining absolute values of differences between amplitudes of corresponding frequency components of the actual frequency spectrum and an expected frequency spectrum, the expected frequency spectrum stored in a database in association with a media identifier corresponding to the media. An example method also includes determining whether spillover occurred based on a summation of the absolute values satisfying a threshold, crediting the media with a media exposure if spillover did not occur.