Patent Publication Number: US-9906833-B2

Title: Methods and systems to monitor a media device using a digital audio signal

Description:
RELATED APPLICATIONS 
     This patent arises from a continuation of U.S. patent application Ser. No. 13/340,167, filed Dec. 29, 2011, entitled “Methods and Systems to Monitor a Media Device Using a Digital Audio Signal.” The entirety of U.S. patent application Ser. No. 13/340,167 is incorporated herein by reference. 
    
    
     FIELD OF THE DISCLOSURE 
     This patent relates generally to home audience measurement, and, more particularly, to methods and systems to monitor a media device using a digital audio signal. 
     BACKGROUND 
     Audience measurement of media, such as television and/or radio programs, is typically carried out by monitoring media exposure of panelists that are statistically selected to represent particular demographic groups. Using various statistical methods, the collected media exposure data is processed to determine the size and demographic composition of the audience(s) for media programs of interest. The audience size and demographic information is valuable to advertisers, broadcasters and/or other entities. For example, audience size and demographic information is a factor in the placement of advertisements, as well as a factor in valuing commercial time slots during particular programs. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates an example activity monitor implemented in accordance with the teachings of this disclosure to monitor a media presentation device. 
         FIG. 2  illustrates an example implementation of the activity monitor of  FIG. 1 . 
         FIG. 3  illustrates an example implementation of the transition detector of  FIG. 2 . 
         FIG. 4  illustrates another example implementation of the activity monitor of  FIG. 1 . 
         FIG. 5  illustrates an example implementation of the meter of  FIG. 1 . 
         FIG. 6  is a flow diagram representative of example machine readable instructions that may be executed to implement the example activity monitor of  FIG. 2 . 
         FIG. 7  is a flow diagram representative of example machine readable instructions that may be executed to implement the example transition detector of  FIG. 3 . 
         FIG. 8  is a flow diagram representative of example machine readable instructions that may be executed to implement the example activity monitor of  FIG. 4 . 
         FIG. 9  is a flow diagram representative of example machine readable instructions that may be executed to implement the example meter of  FIG. 5 . 
         FIG. 10  is a block diagram of an example processor platform that may be used to execute the instructions of  FIGS. 6, 7, 8 , and/or  9  to implement the example activity monitor of  FIG. 2 , the example transition detector of  FIG. 3 , the example activity monitor of  FIG. 4 , the example meter of  FIG. 5 , and/or, more generally, the example system of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     Audience measurement companies enlist persons to participate in measurement panels. Such persons agree to allow the audience measurement company to measure their exposure to media (e.g., television, radio, Internet, advertising, signage, outdoor advertising, etc.). In order to credit audience measurement data with actual panelist exposure, the audience measurement company may wish to monitor an operating state of a media device (e.g., the company may wish to verify that a television is on before crediting viewing of a program on the television). 
     Some prior techniques used to monitor operating states of media devices monitor current flows to the media devices. In such techniques, a current to a media device is measured when the media device is known to be in an on or off state and these measurements are used to determine threshold values for each state. Current levels are then compared to these threshold values to determine the operating state of the media device. However, some media devices are being designed in ways that make the implementation of such techniques more difficult. For example, some media devices are designed with a current limiting soft start where the media device may be in an on state but it may take additional time for the current at the media device to reach the threshold value. In some examples, media devices are designed with cooling systems to operate when the media devices are powered off. In such examples, the current level when the media device is powered off may be greater than the current level when the media device was powered on. These media device designs may lead to inaccurate determinations of operating states of the media devices. 
     Example methods, apparatus, and/or computer readable storage media disclosed herein monitor an operating state of a media device using a digital audio signal and/or collect audio data exchanged at the media device. For instance, some disclosed example methods, apparatus, and/or articles of manufacture attempt to detect a transition in a digital audio signal output by a port of a media device. If the transition is detected, some such disclosed example methods determine the media device is in an on state. If the transition is not detected, some such disclosed example methods determine the media device is in an off state. 
     Some disclosed example methods, apparatus, and/or articles of manufacture attempt to collect audio from a digital signal output by a port of the media device. If the audio is collected, some such disclosed example methods, apparatus, and/or articles of manufacture determine the media device is in an on state. If the audio is not collected, some such disclosed example methods determine the media device is in an off state. 
     Some disclosed example systems include a transition detector to attempt to detect a transition in a digital audio signal output by a port of the media device. If the transition is detected, the transition detector of some such disclosed example systems determines the media device is in an on state. If the transition is not detected, the transition detector of some such disclosed example systems determines the media device is in an off state. 
     Some disclosed example systems include an audio determiner to attempt to collect audio from a digital signal output by a port of the media device. If the audio is collected, the audio determiner of some such disclosed example systems determines the media device is in an on state. If the audio is not collected, the audio determiner of some such disclosed example systems determines the media device is in an off state. 
     Some disclosed example tangible computer-readable storage media include instructions that, when executed, cause a computing device to at least attempt to detect a transition in a digital audio signal output by a port of a media device. The instructions of some such examples cause the computing device to determine the media device is in an on state if the transition is detected. The instructions of some such examples cause the computing device to determine the media device is in an off state if the transition is not detected. 
     Some disclosed example tangible computer-readable storage media include instructions that, when executed, cause a computing device to at least attempt to collect audio from a digital signal output by a port of the media device. The instructions of some such examples cause the computing device to determine the media device is in an on state if the audio is collected. The instructions of some such examples cause the computing device to determine the media device is in an off state if the audio is not collected. 
     Digital signals (e.g., digital audio signals) are often communicated between media devices (e.g., televisions, digital versatile disk (“DVD”) players, computers, stereo systems, and/or game consoles). Media devices are equipped with a variety of interfaces to communicate digital signals between media devices (e.g., Audio Engineering Society 3 (“AES3”) and Sony/Philips Digital Interconnect Format (“S/PDIF”)). In many media devices, a digital signal is present (e.g., communicated) when the media device is operating (e.g., in an on state) and is not present when the media device is not operating (e.g., in an off state). 
     Often times, digital signals are sent using biphase mark code (“BMC”), a form of modulation. BMC, also called Differential Manchester encoding, is a differential encoding technique in which the presence or absence of transitions in a data stream indicates logical value. In the BMC technique, a bit is represented by a transition from one voltage amplitude to another of the same value, but opposite in polarity. Thus, a receiver looks for transitions and where the transitions occur to extract bit values. 
     When data is communicated at a media device using BMC, there will be digital pulses (e.g., logical transitions) in the signal. Thus, digital pulses are present in the signal when the media device is in an on state. Alternatively, digital pulses are not present in the signal when the media device is in an off state. 
     Example activity monitors disclosed herein monitor activities of a media device using a digital audio signal. In some disclosed examples, an activity monitor connects to a port (e.g., an S/PDIF port) of a media presentation device, such as a television, to receive a digital audio signal. The activity monitor of some examples monitors digital pulses on the line to determine an operating state of the media presentation device. Based on transitions in logical values on the line, the activity monitor determines, stores, and/or reports an on or off state of the media presentation device. 
     In some examples, an activity monitor obtains a signal from a port (e.g., an S/PDIF port) on a media presentation device and decodes the signal to determine if the media presentation device is in an on or off state. In some disclosed examples, the activity monitor collects data from the signal and stores and/or transfers the collected data to a meter and/or a central monitoring site. In some examples, the activity monitor collects the signal itself and transfers the signal to a meter and/or a central monitoring site. The example activity monitor transfers operating state data, data collected from a signal, and/or the signal itself to a central data facility and/or a metering device either wirelessly or via a wired connection for further audience measurement processing. 
     Example activity monitors disclosed herein are implemented in the context of panelist audience measurement which may occur, for instance, in the home of the panelist. In some examples, the activity monitor enables a determination of an operating state of a media presentation device and/or collection of data being transferred and/or received by the media presentation device. This information is a factor in determining when and/or whether to monitor (e.g., collect and/or store) audience measurement data and/or whether to credit collected data as actual exposure to media. 
       FIG. 1  illustrates an example activity monitor  102  implemented in accordance with the teachings of this disclosure to monitor a media presentation device  104  using a digital audio signal obtained from a port  106 . The port  106  of the illustrated example forms part of (e.g., is integrated with) the example media presentation device  104 . The port  106  may be, for example, an S/PIDF port. In the illustrated example, the activity monitor  102 , the media presentation device  104 , a home electronic device  108 , and a meter  110  are located in a home monitoring site  112 . The home monitoring site  112  of the illustrated example is a household that has volunteered, has been selected and/or has agreed to participate in a home audience measurement system (e.g., residents of the household have agreed to monitoring of their media exposure activity). 
     The activity monitor  102  of the illustrated example is used to monitor the media presentation device  104  to aid in the processing of audience measurement data obtained at the monitored site  112 . In the illustrated example, the activity monitor  102  connects to the port  106  of the media presentation device  104 . The activity monitor  102  and the port  106  may be connected using, for example, coaxial cables (e.g., with Radio corporation of America (“RCA”) connectors) or optical fiber connections (e.g., with Toshiba Link (“TOSLINK”) connectors). Many devices, such as the media presentation device  104 , are equipped with ports to enable communication with external devices, such as the home electronic device  108 . The media presentation device  104  may be, for example, a television, a radio, a computer, a stereo system, a DVD player, a game console, etc. The home electronic device  108  may be, for example, a DVD player, a digital camera, a game console, a speaker, etc. 
     The activity monitor  102  of the illustrated example operates as a pass-through device so that communication between the media presentation device  104  and the home electronic device  108  is not disturbed (e.g., the media presentation device  104  and/or the home electronic device  108  can be used as normal while the activity monitor  102  is connected). The activity monitor  102  of the illustrated example does not interfere with operation of the media presentation device  104 . The activity monitor  102  and the home electronic device  108  may be connected using, for example, coaxial cables or optical fiber connections. 
     To aid in processing audience measurement data obtained at the monitored site  112 , the activity monitor  102  of the illustrated example monitors signals being output at the port  106  of the media presentation device  104 . In the illustrated example, the activity monitor  102  determines an operating state of the media presentation device  104  (e.g., whether the media presentation device  104  is in an on or off state) by monitoring logical transitions in the signal being output at the port  106 . As described above, if a transition is detected in the signal at the port  106 , the example media presentation device  104  is determined to be powered on. If a transition it not detected in the signal, the example media presentation device  104  is determined to be powered off. While the design of the activity monitor  102  of the illustrated example allows the media presentation device  104  to communicate with the home electronic device  108 , the activity monitor  102  may additionally or alternatively determine an operating state of the media presentation device  104  when an external device (e.g., the home electronic device  108 ) is not connected. 
     To detect a transition in the signal at the media presentation device  104 , the activity monitor  102  of the illustrated example obtains the signal output by the port  106  of the media presentation device. The activity monitor  102  of the illustrated example compares a first state of the signal (e.g., a high or low state) at the port  106  to a second state of the signal (e.g., a high or low state). If the first and second states are different (e.g., the first state is high and the second state is low), the activity monitor  102  of the illustrated example determines a transition in the signal has occurred and, thus, that the media presentation device  104  is in an on state. If the first and second states are the same (e.g., both the first and second states are low), the activity monitor  102  of the illustrated example determines that no transition has occurred in the signal and, thus, that the media presentation device  104  is in an off state. The first and second states may be, for example, sequential bits and/or, for example, some period of time may pass between first and second bits to be compared. 
     In some examples, the activity monitor  102  attempts to collect audio data from the signal at the port  106 . In such examples, the collection of audio data is used by the activity monitor  102  to determine the operating state of the media presentation device  104 . If the signal at the port  106  contains audio data, the media presentation device  104  is operating (e.g., is in an on state). If the signal at the port  106  does not contain audio data, the media presentation device  104  is not operating (e.g., is in an off state). To determine the operating state of the media presentation device  104 , the activity monitor  102  decodes the signal obtained at the port  106  and determines if audio data is present. If audio data is present, the activity monitor  102  determines that the media presentation device  104  is in an on state. If audio data is not present, the activity monitor  102  determines that the media presentation device  104  is in an off state. 
     The operating state of the media presentation device  104  is important in the context of home audience measurement to determine whether to credit collected audience measurement data as data actually presented to an audience. For example, it is possible for a media device, such as a set top box, integrated receiver decoder, cable converter, etc., to output media signals that are not actually presented to an audience because the corresponding information presenting device (e.g., a television) is turned off. Detecting if the information presenting device is on or off is, thus, an important clue in determining whether to credit an audience with exposure to media (e.g., media content or an advertisement), especially in instances where the source device (e.g., the set top box) is monitored to identify content or tuning information and the source device may be left on when the information presenting device is off. 
     In examples where the activity monitor  102  determines an operating state of the media presentation device  104  by decoding a signal obtained at the port  106 , the activity monitor  102  may also collect data from the signal to be used in further processing and/or analysis of audience measurement data. Collected data may include, for example, a type of data transfer occurring, source information, a payload, a media or station identifier code extracted from the audio, metadata, a signature (e.g., an inherent characteristic of the signal that may be used as a fingerprint to identify the signal and/or the media it carries), etc. The activity monitor  102  may also collect the signal itself. 
     Consumers often utilize external media devices (e.g., DVD players, set top boxes, etc.) to view content on media presentation devices, such as the media presentation device  104 . Use of the activity monitor  102  to collect data from signals at the media presentation device  104  is useful in the context of home audience measurement to further analyze collected audience measurement data. 
     Once the activity monitor  102  has determined an operating state of the media presentation device  104  and/or has collected data from the signal at the media presentation device  104 , the activity monitor  102  of the illustrated example stores and timestamps the determined information and/or collected data. For example, the activity monitor  102  stores and timestamps operating state data representative of whether the media presentation device  104  is in an on state or an off state. Operating state data may be, for example, a bit set high to indicate the media presentation device  104  is powered on and/or a bit set low to indicate the media presentation device  104  is powered off. In some examples, the activity monitor  102  additionally or alternatively stores and timestamps data collected from the signal obtained at the port  106  of the media presentation device  104 . 
     In the illustrated example, the activity monitor  102  transmits operating state data, collected data, and/or the signal itself to the meter  110 . The meter  110  of the illustrated example is located at the monitored site  112  to perform local processing of information collected by the example activity monitor  102  and/or any other device used to collect audience measurement data, such as, for example, a people meter which collects information to identify persons in the audience. For example, if the activity monitor  102  provides the meter  110  with a media signal (e.g., an audio portion of a media signal), the meter  110  may process the media signal (or a portion thereof) to extract codes and/or metadata, and/or to generate signatures for use in identifying the media and/or a station transmitting the media. In some examples, the meter  110  may perform the timestamping discussed above. In the illustrated example, the activity monitor  102  and the meter  110  are connected using wired connections. In some examples, the activity monitor  102  transfers information and/or data to the meter  110  wirelessly. 
     The meter  110  of the illustrated example collects and/or processes the home audience measurement data locally and/or transfers the processed data to the remotely located central data facility  114  via the network  116  for further processing. The central facility  114  of the illustrated example collects and/or stores, for example, media exposure data, media monitoring data, and/or demographic information that is collected by multiple media monitoring devices such as, for example, the activity monitor  102  associated with different monitored sites. The central facility  114  may be, for example, a facility associated with The Nielsen Company (US), LLC or any affiliate of The Nielsen Company (US), LLC. The central facility  114  of the illustrated example includes a server  116  and a database  118  that may be implemented using any suitable processor, memory and/or data storage apparatus such as that shown in  FIG. 10 . 
     The network  116  of the illustrated example is used to communicate information and/or data between the example meter  110  and the central facility  114 . The network  116  may be implemented using any type of public and/or private network such as, but not limited to, the Internet, a telephone network, a local area network (“LAN”), a cable network, and/or a wireless network. To enable communication via the network  116 , the meter  110  of the illustrated example includes a communication interface that enables connection to an Ethernet, a digital subscriber line (“DSL”), a telephone line, a coaxial cable, and/or any wireless connection, etc. 
       FIG. 2  is a block diagram of an example implementation of the activity monitor  102  of  FIG. 1 . In the illustrated example, the activity monitor  102  is used to determine an operating state of a media presentation device, for example, the media presentation device  104  of  FIG. 1 . The activity monitor  102  of the illustrated example monitors a signal obtained at the port  106  to determine the operating state of the media presentation device  104 . In the illustrated example, the activity monitor  102  includes a pass through port  202 , an input  204 , a transition detector  206 , a timer  208 , a timestamper  210 , a database  212 , and a transmitter  214 . 
     The pass through port  202  of the illustrated example allows communication between the media presentation device  104  and an external device (e.g., the home electronic device  108 ) to occur undisturbed. The signal obtained at the port  106  is passed to the home electronic device  108  by the pass through port  202  of the illustrated example so that the home electronic device  108  can be used as normal while the activity monitor  102  is connected. The pass through port  202  may contain an input (e.g., a receiver) and an output (e.g., a transmitter) to pass the signal from the port  106  to the home electronic device  108 . If, for example, fiber optic cables (e.g., TOSLINK connectors) are used to connect the media presentation device  104  to the activity monitor  102 , the input within the activity monitor  102  may convert the optical signal to an electrical signal. If, for example, fiber optic cables are used to connect the activity monitor  102  to the home electronic device  108 , the output within the activity monitor  102  may convert the electrical signal to an optical signal. Although the pass through port  202  of the illustrated example allows the activity monitor  102  to monitor the media presentation device  104  while the home electronic device  108  is connected, the activity monitor  102  may monitor the media presentation device  104  when the home electronic device  108  is not connected. 
     The input  204  of the illustrated example is used as a tap to collect the signal from the pass through port  202 . The input  204  of the illustrated example passes the tapped signal to the transition detector  206 . The transition detector  206  of the illustrated example detects a transition in the tapped signal using the timer  208 . If there is a transition in the signal, the transition detector  206  of the illustrated example determines that the media presentation device  104  is in an on state. If no transition is detected in the signal, the transition detector  206  of the illustrated example determines that the media presentation device  104  is in an off state. An example manner of implementing the transition detector  206  is described below in connection with  FIG. 3 . 
     The transition detector  206  of the illustrated example transfers operating state data to the timestamper  210 . The operating state data is indicative of whether the media presentation device  104  is in an on or an off state. Operating state data may be, for example, a bit set high to indicate the media presentation device  104  is in an on state and/or a bit set low to indicate the media presentation device  104  is in an off state. In some examples, the operating state data may be messages indicating if the media presentation device  104  is in an on or an off state. The timestamper  210  of the illustrated example timestamps the operating state data to record times and/or dates at which the media presentation device  104  is in the corresponding operating state. The timestamper  210  passes the timestamped operating state data to the database  212  where the timestamped operating state data is stored. The timestamped operating state data is passed to the transmitter  214  of the illustrated example to be transmitted from the activity monitor  102  to a meter, for example, the meter  110  of  FIG. 1 . 
     In some examples, the transmitter  214  passes operating state data to a central facility, such as the central facility  114  of  FIG. 1 , when no meter  110  is present. In some examples, the operating state data is passed directly from the transition detector  206  to the transmitter  214  to be transmitted to the meter  110  and the meter  110  performs the timestamping (e.g., the timestamper  210  is omitted from the activity monitor  102 ). In the illustrated example, the activity monitor  102  transfers the operating state data to the meter  110  using a wired connection. In other examples, the activity monitor  102  transfers the operating state data to the meter  110  wirelessly. 
     While the example activity monitor  102  has been illustrated in  FIG. 2 , one or more of the elements, processes and/or devices illustrated in  FIG. 2  may be combined, divided, re-arranged, omitted, eliminated and/or implemented in any other way. Further, the pass through port  202 , the input  204 , the transition detector  206 , the timer  208 , the timestamper  210 , the database  212 , the transmitter  214 , and/or, more generally, the example activity monitor  102  of  FIG. 2  may be implemented by hardware, software, firmware and/or any combination of hardware, software and/or firmware. Thus, for example, any of the example pass through port  202 , the input  204 , the transition detector  206 , the timer  208 , the timestamper  210 , the database  212 , the transmitter  214 , and/or, more generally, the example activity monitor  102  of  FIG. 2  could be implemented by one or more circuit(s), programmable processor(s), application specific integrated circuit(s) (“ASIC(s)”), programmable logic device(s) (“PLD(s)”) and/or field programmable logic device(s) (“FPLD(s)”), etc. When any of the apparatus or system claims of this patent are read to cover a purely software and/or firmware implementation, at least one of the example pass through port  202 , the input  204 , the transition detector  206 , the timer  208 , the timestamper  210 , the database  212 , and/or the transmitter  214  are hereby expressly defined to include a tangible computer readable medium such as a memory, DVD, compact disc (“CD”), etc. storing the software and/or firmware. Further still, the example activity monitor  102  of  FIG. 2  may include one or more elements, processes and/or devices in addition to, or instead of, those illustrated in  FIG. 2 , and/or may include more than one of any or all of the illustrated elements, processes and devices. 
       FIG. 3  is a block diagram of an example implementation of the transition detector  206  of  FIG. 2 . In the illustrated example, the transition detector  206  is used to determine an operating state of the media presentation device  104  by detecting a transition in the signal obtained from the input  204  via the pass through port  202 . In the illustrated example, the transition detector  206  includes a first state storer  302 , a second state storer  304 , and a comparator  306 . 
     The first data storer  302  of the illustrated example receives the signal from the input  204  and stores a first state of the signal. The first state of the signal may be a high state or a low state (e.g., a bit set high or a bit set low). The first data storer  302  of the illustrated example uses a clock signal provided by the timer  208  to determine when to pass the signal to the second state storer  304 . For example, the timer  208  may set a time interval that, once lapsed, indicates that the first state storer  302  is to pass the signal to the second state storer  304 . Once the signal is passed from the first state storer  302  to the second state storer  304 , the second state storer  304  of the illustrated example stores a second state of the signal. The second state of the signal may be a high state or a low state (e.g., a bit set high or a bit set low). The passing of the signal may be a continuous process such that, as the second state storer  304  is storing a second state of the signal, the first state storer  302  is storing a next first state of the signal. This process allows the transition detector  206  of the illustrated example to continuously compare states of the signal. 
     The first state storer  302  of the illustrated example passes the first state of the signal to the comparator  306 . The second state storer  304  of the illustrated example passes the second state of the signal to the comparator  306 . The comparator  306  of the illustrated example compares the first state and the second state to determine if there has been a transition in the signal. If the first state of the signal is equal (e.g., substantially the same as, within a degree of tolerance) to the second state of the signal (e.g., the first state is a bit set high and the second state is a bit set high), the comparator  306  of the illustrated example determines that there has been no transition in the signal and, thus, that the media presentation device  104  is in an off state. If the first state of the signal is different than the second state of the signal (e.g., the first state is a bit set high and the second state is a bit set low), the comparator  306  of the illustrated example determines that there has been a transition in the signal and, thus, that the media presentation device  104  is in an on state. Whether the signal starts in a high or low state is unimportant to the comparator  306  because the comparator  306  is concerned with transitions in the signal, not the values themselves, and transitions are present in the signal when the media presentation device  104  is in an on state. The comparator  306  of the illustrated example passes operating state data indicative of whether the media presentation device  104  is in an on or off state to the timestamper  210 . Operating state data may be, for example, a bit set high to indicate the media presentation device  104  is in an on state and/or a bit set low to indicate the media presentation device  104  is in an off state. In some examples, the operating state data is a message indicating if the media presentation device  104  is in an on state or an off state. 
     While the example transition detector  206  has been illustrated in  FIG. 3 , one or more of the elements, processes and/or devices illustrated in  FIG. 3  may be combined, divided, re-arranged, omitted, eliminated and/or implemented in any other way. Further, the first state storer  302 , the second state storer  304 , the comparator  306 , and/or, more generally, the example transition detector  206  of  FIG. 3  may be implemented by hardware, software, firmware and/or any combination of hardware, software and/or firmware. Thus, for example, any of the example first state storer  302 , the second state storer  304 , the comparator  306 , and/or, more generally, the example transition detector  206  of  FIG. 3  could be implemented by one or more circuit(s), programmable processor(s), ASIC(s), PLD(s) and/or FPLD(s), etc. When any of the apparatus or system claims of this patent are read to cover a purely software and/or firmware implementation, at least one of the example first state storer  302 , the second state storer  304 , and/or the comparator  306  are hereby expressly defined to include a tangible computer readable medium such as a memory, DVD, CD, Blu-ray, etc. storing the software and/or firmware. Further still, the example transition detector  206  of  FIG. 3  may include one or more elements, processes and/or devices in addition to, or instead of, those illustrated in  FIG. 3 , and/or may include more than one of any or all of the illustrated elements, processes and devices. 
       FIG. 4  is a block diagram of another example implementation of the activity monitor  102  of  FIG. 1 . In the illustrated example, the activity monitor  102  determines an operating state of the media presentation device  104  by decoding the signal obtained at the port  106 . The activity monitor  102  of the illustrated example also collects data from the signal obtained at the port  106 . In the illustrated example, the activity monitor  102  includes the pass through port  202 , the input  204 , an audio determiner  402 , the timestamper  210 , the database  212 , and the transmitter  214 . The pass through port  202 , the input  204 , the timestamper  210 , the database  212 , and the transmitter  214  are similar to their counterparts in the example of  FIG. 2  and, thus, have been assigned the same reference numerals. Elements numbered with like reference numbers are substantially similar and/or identical and, thus, are not redescribed in detail here. Instead, the interested reader is referred to the above descriptions of the like numbered elements for a full and complete description of the same. 
     The audio determiner  402  of the illustrated example receives a signal obtained at the port  106  via the pass through port  202  and the input  204 . The audio determiner  402  of the illustrated example decodes the signal to determine the operating state of the media presentation device  104  and to collect data for further audience measurement processing. The audio determiner  402  may decode the signal using any appropriate decoding method and/or technique. Once the signal has been decoded, the audio determiner  402  of the illustrated example determines if audio data is present. If audio data is present, the audio determiner  402  of the illustrated example determines that the media presentation device  104  is in an on state. If audio data is not present for more than a threshold period of time, the audio determiner  402  of the illustrated example determines that the media presentation device  402  is in an off state. The audio determiner  402  of the illustrated example passes operating state data indicative of whether the media presentation device  104  is in an on or off state to the timestamper  210 . Operating state data may be, for example, a bit set high to indicate the media presentation device  104  is in an on state and/or a bit set low to indicate the media presentation device  104  is in an off state and/or a message to indicate an on or off state. The timestamper  210  timestamps the operating state data, the database  212  stores the operating state data, and the transmitter  214  transmits the operating state data to the meter  110 . 
     The audio determiner  402  of the illustrated example also collects data from the signal obtained from the data input  402 . Collected data may include, for example, a type of data transfer occurring, source information, a payload, a code, metadata, a signature and/or the audio signal itself. The audio determiner  402  of the illustrated example transfers the collected data to the timestamper  210  to be timestamped and stored in the database  212 . The timestamped data is passed to the transmitter  214  of the illustrated example to be transmitted to the meter  110 . In some examples, the audio determiner  402  transfers the signal itself and/or collected data to the meter  110 . In some examples, the transmitter  214  transfers collected data and/or the audio signal to a central facility, for example, the central facility  114  of  FIG. 1 , when no meter  110  is present. In some examples, the audio determiner  402  transfers the data and/or the audio signal directly to the transmitter  214  to be transmitted to the meter  110  and the meter performs the timestamping (e.g., the timestamper  210  is omitted from the activity monitor  102 ). In the illustrated example, the activity monitor  102  transfers the collected data and/or the audio signal to the meter  110  using a wired connection. In some examples, the activity monitor  102  transfers the collected data and/or the audio signal to the meter  110  wirelessly. 
     While the example activity monitor  102  has been illustrated in  FIG. 4 , one or more of the elements, processes and/or devices illustrated in  FIG. 4  may be combined, divided, re-arranged, omitted, eliminated and/or implemented in any other way. Further, the pass through port  202 , the input  204 , the timestamper  210 , the database  212 , the transmitter  214 , the audio determiner  402 , and/or, more generally, the example activity monitor  102  of  FIG. 4  may be implemented by hardware, software, firmware and/or any combination of hardware, software and/or firmware. Thus, for example, any of the example pass through port  202 , the input  204 , the timestamper  210 , the database  212 , the transmitter  214 , the audio determiner  402 , and/or, more generally, the example activity monitor  102  of  FIG. 4  could be implemented by one or more circuit(s), programmable processor(s), ASIC(s), PLD(s) and/or FPLD(s), etc. When any of the apparatus or system claims of this patent are read to cover a purely software and/or firmware implementation, at least one of the example pass through port  202 , the input  204 , the timestamper  210 , the database  212 , the transmitter  214 , and/or the audio determiner  402  are hereby expressly defined to include a tangible computer readable medium such as a memory, DVD, CD, Blu-ray, etc. storing the software and/or firmware. Further still, the example activity monitor  102  of  FIG. 4  may include one or more elements, processes and/or devices in addition to, or instead of, those illustrated in  FIG. 4 , and/or may include more than one of any or all of the illustrated elements, processes and devices. 
       FIG. 5  is a block diagram of an example implementation of the meter  110  of  FIG. 1 . The meter  110  of the illustrated example is used to collect, aggregate, locally process, and/or transfer data to a central data facility, such as the central data facility  114 , via the network  116  of  FIG. 1 . In the illustrated example, the meter  110  is used to extract and/or analyze codes and/or signatures from data and/or signals collected by the activity monitor  102  and/or input to the meter  110  in another manner (e.g., free field audio detected by the meter  110  with a microphone exposed to ambient sound). The meter  110  of the illustrated example includes an input  502 , a code collector  504 , a signature generator  506 , control logic  508 , a database  510 , and a transmitter  512 . 
     Identification codes, such as watermarks, ancillary codes, etc. may be embedded within media signals. Identification codes are digital data that are inserted into content (e.g., audio) to uniquely identify broadcasters and/or media (e.g., content or advertisements), and/or are carried with the media for another purpose such as tuning (e.g., packet identifier headers (“PIDs”) used for digital broadcasting). Codes are typically extracted using a decoding operation. 
     Signatures are a representation of some characteristic of the media signal (e.g., a characteristic of the frequency spectrum of the signal). Signatures can be thought of as fingerprints. They are typically not dependent upon insertion of identification codes in the media, but instead preferably reflect an inherent characteristic of the media and/or the media signal. Systems to utilize codes and/or signatures for audience measurement are long known. See, for example, Thomas, U.S. Pat. No. 5,481,294, which is hereby incorporated by reference in its entirety. 
     In the illustrated example, the input  502  obtains a data signal from a device, such as the activity monitor  102 . In some examples, the input  502  is a microphone exposed to ambient sound in a monitored location and serves to collect audio played by an information presenting device. As described above, the activity monitor  102  may collect data and/or an output of signal (e.g., the audio component) from the media presentation device  104 . Thus, in some examples, the input  502  receives the signal or a portion of the signal (e.g., the audio) from the activity monitor  102 . The input  502  of the illustrated example passes the received signal (e.g., a digital audio signal) to the code collector  504  and/or the signature generator  506 . The code collector  504  of the illustrated example extracts codes and/or the signature generator  506  generates signatures from the signal to identify broadcasters, channels, stations, and/or programs. The control logic  508  of the illustrated example is used to control the code collector  504  and the signature generator  506  to cause collection of a code, a signature, or both a code and a signature. The identified codes and/or signatures are stored in the database  510  of the illustrated example and are transmitted to the central facility  114  via the network  116  by the transmitter  512  of the illustrated example. Although the example of  FIG. 5  collects codes and/or signatures from an audio signal, codes or signatures can additionally or alternatively be collected from other portion(s) of the signal (e.g., from the video portion). 
     While an example meter  110  has been illustrated in  FIG. 5 , one or more of the elements, processes and/or devices illustrated in  FIG. 5  may be combined, divided, re-arranged, omitted, eliminated and/or implemented in any other way. Further the input  502 , the code collector  504 , the signature generator  506 , the control logic  508 , the database  510 , the transmitter  512 , and/or, more generally, the example meter  110  of  FIG. 5  may be implemented by hardware, software, firmware and/or any combination of hardware, software and/or firmware. Thus, for example, any of the example input  502 , the code collector  504 , the signature generator  506 , the control logic  508 , the database  510 , the transmitter  512 , and/or, more generally, the example meter  110  of  FIG. 5  could be implemented by one or more circuit(s), programmable processor(s), ASIC(s), PLD(s) and/or FPLD(s), etc. When any of the apparatus or system claims of this patent are read to cover a purely software and/or firmware implementation, at least one of the example input  502 , the code collector  504 , the signature generator  506 , the control logic  508 , the database  510 , the transmitter  512 , and/or the meter  110  are hereby expressly defined to include a tangible computer readable medium such as a memory, DVD, CD, Blu-ray, etc. storing the software and/or firmware. Further still, the example meter  110  of  FIG. 5  may include one or more elements, processes and/or devices in addition to, or instead of, those illustrated in  FIG. 5 , and/or may include more than one of any or all of the illustrated elements, processes and devices. 
     A flowchart representative of example machine readable instructions for implementing the example activity monitor  102  of  FIG. 2  is shown in  FIG. 6 . In this example, the machine readable instructions comprise a program for execution by a processor such as the processor  1012  shown in the example processor platform  1000  discussed below in connection with  FIG. 10 . The program may be embodied in software stored on a tangible computer readable medium such as a compact disc read-only memory (“CD-ROM”), a floppy disk, a hard drive, a DVD, Blu-ray disk, or a memory associated with the processor  1012 , but the entire program and/or parts thereof could alternatively be executed by a device other than the processor  1012  and/or embodied in firmware or dedicated hardware. Further, although the example program is described with reference to the flowchart illustrated in  FIG. 6 , many other methods of implementing the example activity monitor  102  may alternatively be used. For example, the order of execution of the blocks may be changed, and/or some of the blocks described may be changed, eliminated, or combined. 
     As mentioned above, the example process of  FIG. 6  may be implemented using coded instructions (e.g., computer readable instructions) stored on a tangible computer readable medium such as a hard disk drive, a flash memory, a read-only memory (“ROM”), a CD, a DVD, a cache, a random-access memory (“RAM”) and/or any other storage media in which information is stored for any duration (e.g., for extended time periods, permanently, brief instances, for temporarily buffering, and/or for caching of the information). As used herein, the term tangible computer readable medium is expressly defined to include any type of computer readable storage and to exclude propagating signals. Additionally or alternatively, the example process of  FIG. 6  may be implemented using coded instructions (e.g., computer readable instructions) stored on a non-transitory computer readable medium such as a hard disk drive, a flash memory, a read-only memory, a compact disk, a digital versatile disk, a cache, a random-access memory and/or any other storage media in which information is stored for any duration (e.g., for extended time periods, permanently, brief instances, for temporarily buffering, and/or for caching of the information). As used herein, the term non-transitory computer readable medium is expressly defined to include any type of computer readable medium and to exclude propagating signals. As used herein, when the phrase “at least” is used as the transition term in a preamble of a claim, it is open-ended in the same manner as the term “comprising” is open ended. Thus, a claim using “at least” as the transition term in its preamble may include elements in addition to those expressly recited in the claim. 
       FIG. 6  is a flow diagram representative of example machine readable instructions that may be executed to implement the example activity monitor  102  of  FIG. 2 . The activity monitor  102  of the illustrated example is used to determine an operating state of a media presentation device, such as the media presentation device  104 . The operating state of the media presentation device  104  is useful in the context of home audience measurement for example, to allow an audience measurement company to decide whether to credit audience exposure to media. 
     Initially, the input  204  of the illustrated example obtains a signal at the port  106  of the media presentation device  104  via the pass through port  202  (block  602 ). The input  204  of the illustrated example passes the signal to the transition detector  206 . The transition detector  206  of the illustrated example attempts to detect a transition in the signal from the input  204  using the timer  208  (block  604 ). If a transition in the signal is detected, the transition detector  206  of the illustrated example determines the media presentation device  104  is in an on state (block  606 ). If a transition is not detected in the signal, the transition detector  206  of the illustrated example determines the media presentation device is in an off state (block  608 ). 
     The transition detector  206  of the illustrated example sends operating state data representative of whether the media presentation device  104  is in an on state or in an off state (e.g., a bit set high to indicate an on state and/or a bit set low to indicate an off state and/or a message indicating an on or off state) to the timestamper  210 . The timestamper  210  of the illustrated example timestamps the operating state data (block  610 ) and sends the timestamped operating state data to the database  212 . The database  212  of the illustrated example stores the timestamped operating state data (block  612 ) and sends the timestamped operating state data to the transmitter  214 . The transmitter  214  of the illustrated example transmits the operating state data to, for example, a meter (e.g., the meter  110  of  FIG. 1 ) (block  614 ). Control then returns to block  602  when the instructions are completed. 
     A flowchart representative of example machine readable instructions for implementing the example transition detector  206  of  FIG. 3  is shown in  FIG. 7  and described below. In this example, the machine readable instructions comprise a program for execution by a processor such as the processor  1012  shown in the example processor platform  1000  discussed below in connection with  FIG. 10 . The program may be embodied in software stored on a tangible computer readable medium such as a CD-ROM, a floppy disk, a hard drive, a DVD, Blu-ray disk, or a memory associated with the processor  1012 , but the entire program and/or parts thereof could alternatively be executed by a device other than the processor  1012  and/or embodied in firmware or dedicated hardware. Further, although the example program is described with reference to the flowchart illustrated in  FIG. 7 , many other methods of implementing the example transition detector  206  may alternatively be used. For example, the order of execution of the blocks may be changed, and/or some of the blocks described may be changed, eliminated, or combined. 
     As mentioned above, the example process of  FIG. 7  may be implemented using coded instructions (e.g., computer readable instructions) stored on a tangible computer readable medium such as a hard disk drive, a flash memory, a ROM, a CD, a DVD, a cache, a RAM and/or any other storage media in which information is stored for any duration (e.g., for extended time periods, permanently, brief instances, for temporarily buffering, and/or for caching of the information). Additionally or alternatively, the example process of  FIG. 7  may be implemented using coded instructions (e.g., computer readable instructions) stored on a non-transitory computer readable medium such as a hard disk drive, a flash memory, a read-only memory, a compact disk, a digital versatile disk, a cache, a random-access memory and/or any other storage media in which information is stored for any duration (e.g., for extended time periods, permanently, brief instances, for temporarily buffering, and/or for caching of the information). 
       FIG. 7  is a flow diagram representative of example machine readable instructions that may be executed to implement the example transition detector  206  of  FIG. 3 . The transition detector  206  of the illustrated example is used to determine an operating state of the media presentation device  104  by detecting a transition in a signal obtained from the media presentation device  104 . 
     Initially, the transition detector  206  of the illustrated example obtains the signal from the input  204  (block  702 ). The first data storer  302  of the illustrated example receives the signal from the input  204  and stores a first state of the signal (block  704 ). The first state of the signal may be a high state or a low state (e.g., a bit set high or a bit set low). The first data storer  302  of the illustrated example uses a clock signal provided by the timer  208  to determine when to pass the signal to the second state storer  304 . Once the signal is passed from the first state storer  302 , the second state storer  304  of the illustrated example stores a second state of the signal (block  706 ). The second state of the signal may be a high state or a low state (e.g., a bit set high or a bit set low). The passing of the signal may be a continuous process such that, as the second state storer  304  is storing a second state of the signal, the first state storer  302  is storing a next first state of the signal. This process allows the transition detector  206  of the illustrated example to continuously compare states of the signal. 
     The first state storer  302  of the illustrated example passes the first state of the signal to the comparator  306 . The second state storer  304  of the illustrated example passes the second state of the signal to the comparator  306 . The comparator  306  of the illustrated example compares the first state and the second state to determine if there has been a transition in the signal (block  708 ). If the first state of the signal is equal to the second state of the signal (e.g., the first state is a bit set high and the second state is a bit set high), the comparator  306  of the illustrated example determines that there has been no transition in the signal and, thus, that the media presentation device  104  is in an off state (block  710 ). If the first state of the signal is different than the second state of the signal (e.g., the first state is a bit set high and the second state is a bit set low), the comparator  306  of the illustrated example determines that there has been a transition in the signal and, thus, that the media presentation device  104  is in an on state (block  712 ). The comparator  306  of the illustrated example passes operating state data indicative of whether the media presentation device  104  is in an on or off state to the timestamper  210  (block  714 ). Operating state data may be, for example, a bit set high to indicate the media presentation device  104  is in an on state and/or a bit set low to indicate the media presentation device  104  is in an off state and/or a message indicating an on or off state. The process ends when the instructions are complete (block  716 ). 
     A flowchart representative of example machine readable instructions for implementing the example activity monitor  102  of  FIG. 4  is shown in  FIG. 8 . In this example, the machine readable instructions comprise a program for execution by a processor such as the processor  1012  shown in the example processor platform  1000  discussed below in connection with  FIG. 10 . The program may be embodied in software stored on a tangible computer readable medium such as a CD-ROM, a floppy disk, a hard drive, a DVD, Blu-ray disk, or a memory associated with the processor  1012 , but the entire program and/or parts thereof could alternatively be executed by a device other than the processor  1012  and/or embodied in firmware or dedicated hardware. Further, although the example program is described with reference to the flowchart illustrated in  FIG. 8 , many other methods of implementing the example activity monitor  102  may alternatively be used. For example, the order of execution of the blocks may be changed, and/or some of the blocks described may be changed, eliminated, or combined. 
     As mentioned above, the example process of  FIG. 8  may be implemented using coded instructions (e.g., computer readable instructions) stored on a tangible computer readable medium such as a hard disk drive, a flash memory, a ROM, a CD, a DVD, a cache, a RAM and/or any other storage media in which information is stored for any duration (e.g., for extended time periods, permanently, brief instances, for temporarily buffering, and/or for caching of the information). Additionally or alternatively, the example process of  FIG. 8  may be implemented using coded instructions (e.g., computer readable instructions) stored on a non-transitory computer readable medium such as a hard disk drive, a flash memory, a read-only memory, a compact disk, a digital versatile disk, a cache, a random-access memory and/or any other storage media in which information is stored for any duration (e.g., for extended time periods, permanently, brief instances, for temporarily buffering, and/or for caching of the information). 
       FIG. 8  is a flow diagram representative of example machine readable instructions that may be executed to implement the example activity monitor  102  of  FIG. 4 . In the illustrated example, the activity monitor  102  determines an operating state of the media presentation device  104  by decoding a signal obtained at the port  106 . The activity monitor  102  of the illustrated example also collects data from the signal obtained at the port  106 . 
     Initially, the input  204  of the illustrated example obtains the signal from the port  106  of the media presentation device  104  via the pass through port  202  (block  802 ). The signal is then passed to the audio determiner  402 . The audio determiner  402  of the illustrated example decodes the signal (block  804 ). The audio determiner  402  may decode the signal using any appropriate decoding method and/or technique. Once the signal has been decoded, the audio determiner  402  of the illustrated example determines if audio data is present (block  806 ). If audio data is not present, the audio determiner  402  of the illustrated example determines that the media presentation device  402  is in an off state (block  808 ). If audio data is present, the audio determiner  402  of the illustrated example determines that the media presentation device  104  is in an on state (block  810 ). The audio determiner  402  of the illustrated example collects data from the signal obtained from the data input  402  (block  812 ). Collected data may include, for example, a type of data transfer occurring, source information, a payload, a code, metadata, a signature and/or the audio signal itself. 
     The audio determiner  402  of the illustrated example passes operating state data indicative of whether the media presentation device  104  is in an on or off state and/or collected data to the timestamper  210 . Operating state data may be, for example, a bit set high to indicate the media presentation device  104  is in an on state and/or a bit set low to indicate the media presentation device  104  is in an off state and/or a message indicating an on or off state. The timestamper  210  of the illustrated example timestamps the operating state data and/or collected data received from the audio determiner  402  (block  814 ) and passes the operating state data and/or collected data to the database  212 . The database  212  of the illustrated example stores the operating state data and/or collected data (block  816 ) and passes the operating state data and/or collected data to the transmitter  214 . The transmitter  214  of the illustrated example transmits the operating state data and/or collected data to the meter  110  (block  818 ). In some examples, the audio determiner  402  transfers collected data and/or the signal itself directly to the meter  110 . In some examples, the transmitter  214  transfers data and/or the audio signal directly to a central facility, for example, the central facility  114  of  FIG. 1 , when no meter  110  is present. In some examples, the audio determiner  402  transfers the data and/or the audio signal directly to the transmitter  214  to be transmitted to the meter  110  and the meter performs the timestamping. Control returns to block  802  when the instructions are complete. 
     A flowchart representative of example machine readable instructions for implementing the example meter  110  of  FIG. 5  is shown in  FIG. 9 . In this example, the machine readable instructions comprise a program for execution by a processor such as the processor  1012  shown in the example processor platform  1000  discussed below in connection with  FIG. 10 . The program may be embodied in software stored on a tangible computer readable medium such as a CD-ROM, a floppy disk, a hard drive, a DVD, or a memory associated with the processor  1012 , but the entire program and/or parts thereof could alternatively be executed by a device other than the processor  1012  and/or embodied in firmware or dedicated hardware. Further, although the example program is described with reference to the flowchart illustrated in  FIG. 10 , many other methods of implementing the example meter  110  may alternatively be used. For example, the order of execution of the blocks may be changed, and/or some of the blocks described may be changed, eliminated, or combined. 
     As mentioned above, the example process of  FIG. 9  may be implemented using coded instructions (e.g., computer readable instructions) stored on a tangible computer readable medium such as a hard disk drive, a flash memory, a ROM, a CD, a DVD, a cache, a RAM and/or any other storage media in which information is stored for any duration (e.g., for extended time periods, permanently, brief instances, for temporarily buffering, and/or for caching of the information). Additionally or alternatively, the example process of  FIG. 9  may be implemented using coded instructions (e.g., computer readable instructions) stored on a non-transitory computer readable medium such as a hard disk drive, a flash memory, a ROM, a CD, a DVD, a cache, a RAM and/or any other storage media in which information is stored for any duration (e.g., for extended time periods, permanently, brief instances, for temporarily buffering, and/or for caching of the information). 
       FIG. 9  is a flow diagram representative of example machine readable instructions that may be executed to implement the example meter  110  of  FIG. 5 . The meter  110  of the illustrated example is used to collect, aggregate, locally process, and/or transfer data to a central data facility, such as the central data facility  114 . In the illustrated example, the meter  110  is used to extract and/or analyze codes and/or signatures from data and/or signals collected by the example activity monitor  102  and/or received via other channels. The data collected by the meter  110  of the illustrated example is used in the context of home audience measurement to facilitate the collection and/or analysis of audience measurement data. 
     Initially, the input  502  of the illustrated example obtains a signal from the activity monitor  102  or via another channel (e.g., from free field audio sampled by a microphone of the meter  110  for a different device, etc.) (block  902 ). The control logic  508  of the illustrated example determines whether to collect a code or generate a signature from the signal obtained at the input  502  (block  904 ). In the illustrated example, either a code is collected or a signature is generated from the signal. In other examples, both a code and a signature are collected and/or generated. 
     If a code is to be collected, the code collector  504  of the illustrated example collects a code from the signal obtained at the input  502  (block  906 ). The code collector  504  of the illustrated example passes the collected code(s) to the database  510 . If a signature is to be generated, the signature generator  506  generates a signature from the signal obtained at the input  502  (block  908 ). The signature generator  506  of the illustrated example passes the generated signature(s) to the database  510 . The database  510  of the illustrated example stores the collected codes and/or generated signatures (block  910 ) and passes the codes and/or signatures to the transmitter  512 . The transmitter  512  of the illustrated example transmits the collected codes and/or generated signatures to the central facility  114  via a network, such as the network  116 . Control then returns to block  902  when the instructions are completed. 
       FIG. 10  is a block diagram of an example processor platform  1000  capable of executing the instructions of  FIGS. 6, 7, 8 , and/or  9  to implement the example activity monitor  102  of  FIG. 2 , the example transition monitor  206  of  FIG. 3 , the example activity monitor  102  of  FIG. 4 , the example meter  110  of  FIG. 5 , and/or the system of  FIG. 1 . The processor platform  1000  can be, for example, a server, a personal computer, an Internet appliance, a set top box, or any other type of computing device. 
     The system  1000  of the instant example includes a processor  1012 . For example, the processor  1012  can be implemented by one or more microprocessors or controllers from any desired family or manufacturer. 
     The processor  1012  includes a local memory  1013  (e.g., a cache) and is in communication with a main memory including a non-volatile memory  1014  and a volatile memory  1016  via a bus  1018 . The volatile memory  1016  may be implemented by Synchronous Dynamic Random Access Memory (“SDRAM”), Dynamic Random Access Memory (“DRAM”), RAMBUS Dynamic Random Access Memory (“RDRAM”) and/or any other type of random access memory device. The non-volatile memory  1014  may be implemented by flash memory and/or any other desired type of memory device. Access to the main memory  1014 ,  1016  is controlled by a memory controller. 
     The processor platform  1000  also includes an interface circuit  1020 . The interface circuit  1020  may be implemented by any type of interface standard, such as an Ethernet interface, a universal serial bus (USB), and/or a PCI express interface. 
     One or more input devices  1022  are connected to the interface circuit  1020 . The input device(s)  1022  permit a user to enter data and commands into the processor  1012 . The input device(s) can be implemented by, for example, a keyboard, a mouse, a touchscreen, a track-pad, and/or a trackball. 
     One or more output devices  1024  are also connected to the interface circuit  1020 . The output devices  1024  can be implemented, for example, by display devices (e.g., a liquid crystal display, a cathode ray tube display (“CRT”), a printer and/or speakers). The interface circuit  1020 , thus, typically includes a graphics driver card. 
     The interface circuit  1020  also includes a communication device such as a modem or network interface card to facilitate exchange of data with external computers via a network  1026  (e.g., an Ethernet connection, a DSL, a telephone line, coaxial cable, a cellular telephone system, etc.). 
     The processor platform  1000  also includes one or more mass storage devices  1028  for storing software and data. Examples of such mass storage devices  1028  include floppy disk drives, hard drive disks, compact disk drives and DVD drives. The mass storage device  1028  may implement a local storage device. 
     The coded instructions  1032  of  FIGS. 6, 7, 8 , and/or  9  may be stored in the mass storage device  1028 , in the volatile memory  1016 , in the non-volatile memory  1014 , and/or on a removable storage medium such as a CD or DVD. 
     Although certain example methods, systems, apparatus, and articles of manufacture have been described herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all methods, systems and articles of manufacture fairly falling within the scope of the claims of this patent.