Abstract:
A method and apparatus for monitoring use patterns or services available information in video distribution networks. A network termination unit receives the video content through a port, demodulates and decodes the signals to produce display signals. The display signals are displayed on a viewing device connected to the network termination unit and the network termination unit monitors the use patterns and/or services available information of the viewing device. The unit then formats the use patterns or services available information into use pattern network packets and transmits them. A content analyzer receives use pattern packet from a network termination unit and decode them to access the data. The content analyzer then analyzes the use patterns and/or services available information and characterizes the unit. The characterization of the unit is then used to target content to that unit.

Description:
BACKGROUND 
     1. Field 
     This disclosure relates to methods for collecting and reporting content in video streams, more particularly to methods for collecting and reporting content in video streams. 
     2. Background 
     The transmission of video content via cable is a fairly complex process. In the digital cable market, for example, the content is distributed from regional centers. Each region center is often referred to as a head-end. The head-end assembles multiple sources of video content, typically in MPEG (Moving Picture Experts Group) format for digital video. This multiple sources are then groomed into a preferred set of programs. 
     The preferred set of programs is then replicated as needed and transmitted to local hubs for the digital cable network. Currently, this transmission is done using DVB-ASI framing around digital video MPEG-2 transport packets, but may also be done via an Internet Protocol (IP) network. In order to transmit this data across these networks, the MPEG programs are broken up into standardized packets, with each packet being an IP packet. While not currently being used, the packets could also be frames for a Frame Relay network or packets for an Asynchronous Transfer Mode (ATM) network. 
     The MPEG programs encapsulated into IP packets are then multicast or unicast to the various local hubs, referred to as distribution hubs (D-hubs). When the IP packets arrive at the D-hub, the MPEG programs are reconstructed using the known characteristics of the IP packets, such as the time stamps, etc., that allow the programs to be reconstructed correctly. The programming sets are then sent to equipment that converts the MPEG signals into modulated RF (radio frequency) signals. The RF signals are received by network termination units, such as cable set top boxes and cable modems. The programs are then demodulated as desired for display by the viewing device, such as a television or cable modem. 
     Currently, most auxiliary information that accompanies the programs, including advertising, can only be targeted at a very high level. For example, most of the head-ends and D-hubs can be sent particular geographic information. Alternative or in addition to the geographic targeting, predictive analysis techniques can be used. An example of this is the data provided by Nielsen Research. It would seem useful to have some way to more closely tailor the information sent along with the programs. 
     SUMMARY 
     One aspect of the disclosure is a network termination unit. The unit includes a port to receive video content signals, which may include programs and/or advertising. The unit also includes a demodulator operable to demodulate the video content signals and a decoder operable to decode the demodulated signals into display signals. The network termination unit is typically attached to a viewing device operable to display the display signals. A module in the unit may monitor the use patterns or services available information of a user viewing the display signals and form use pattern network packets, or simply monitor all services ‘seen’ at that point of the network that are transmitted back through the video distribution network. 
     Another aspect of the disclosure is a content analyzer resident on the video distribution network that receives the use pattern packets and decodes them. The content analyzer then analyzes the decoded data and characterizes the network termination unit sending the packets. This characterization is then use by the system to target video content to that unit. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention may be best understood by reading the disclosure with reference to the drawings, wherein: 
         FIG. 1  shows one embodiment of a video content distribution network, in accordance with the invention. 
         FIG. 2  shows one embodiment of a network termination unit, in accordance with the invention. 
         FIG. 3  shows one embodiment of a content analyzer, in accordance with the invention. 
         FIG. 4  shows one embodiment of a method to transmit content information, in accordance with the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     An embodiment of a video distribution network  10  in accordance with the invention is shown in  FIG. 1 . A regional distribution center  12 , referred to as the head end, receives a set of programs in MPEG format. The head-end  12  then breaks up these programs into network packets, for example IP packets. The term packet as used here includes frame relay network frames, as well as packets for asynchronous transfer mode networks. 
     The resulting packets are then place on the network between the head end and the distribution hub  14 . The distribution hub then reconstructs the programs from the packets, using the characteristics of the packets defined by the network standard. For example, packets across an IP network typically have a timestamp in the header that allows the packets to be reordered into their proper order. The distribution hub then reassembles the program data from the packets, removing the encapsulation and reconstructing the programs. 
     Once reconstructed, the distribution hub  14  then converts the programs into radio frequency (RF) signals for transmission across a coaxial cable network to the cable subscribers. The RF signals are typically decoded and converted to display signals by a network termination unit, or NTU  16 . The NTU  16  decodes and converts the signals into the display format necessary for the associated viewing device  18 . If the viewing device  18  is a television, for example, the NTU would be a set-top box. If the viewing device  18  is a personal computer or other computing device, the NTU would be a cable modem. Note that the term computing device, as used here, is any device that receives signals from a cable modem and converts them into viewable format. 
     An embodiment of the NTU is shown in  FIG. 2 . As mentioned previously, the NTU could be a cable set-top box for television or a cable modem, as examples. The NTU  16  has a port  20  operable to receive incoming content. The content may include video content such as the programs, mentioned previously as well as associated information, such as advertising, as well as other types of content as discussed below. The content will more than likely be in the form of modulated RF signals from the distribution hub  14  of  FIG. 1 . Therefore, a demodulator would be needed to demodulate the RF signals into the original MPEG or other transport stream. The demodulator is operable to demodulate the signals of the channel selected by the user. A decoder  24  then decodes the MPEG transport stream and converts it into display signals appropriate for the viewing device of the user. These display signals are then transmitted to the display. 
     Detection module  26  detects the signals resulting from the demodulation. In one embodiment the module  26  detects the signals prior to being decoded from the MPEG format. This allows the module to decode the transport stream identifier (TSID) of a given MPEG program. The TSIDs of programs selected over a period of time would then be stored as use pattern or services available information in the detection module. However, it is possible that the detection could be done at other points in the process of converting the incoming signals to the display signals and this is intended only as an example. Using the TSIDs, however, has the advantage of using a mechanism that is already present in the system, without having to add anything. 
     The resulting TSIDs or other data used to track use patterns or services available information or services available information may be stored in the storage  28 . The detection module  26  would then periodically send usage information back to the distribution hub or head end to allow analysis of the use patterns. Typically, the analysis will not be performed by the set-top box or cable modem. Generally, the desire is to keep these devices inexpensive and small, and the addition of extra circuitry and memory to them would be counter to these goals. 
     In order for the use patterns or services available information or services available information to be transmitted back to the distribution hub or the head end, the patterns or information would have to be encapsulated in such a manner that the receiver would be able to recognize them as use pattern packets. Generally, the network packets mentioned above conform to a standard format, with a header and a payload. The header normally contains information about the payload data, including the time stamp or some other means to identify the ordering of the data in a larger set of data. In addition, there are flags or other indicators that announce the type of payload data in that packet. 
     In one embodiment of the invention, the header includes at least one flag bit that would identify the payload as use pattern or services available data. Both of these types of information will be formatted into packets referred to as use pattern packets. The format of the header that identifies use pattern packets, as well as the format of the payload data, will be referred to as content discovery protocol. The content discovery protocol will allow the video distribution network to identify those packets as use pattern packets and route them to the appropriate point in the network. 
     The use pattern packets should be routed to a content analyzer at some point in the network. The point may be at the distribution hub or at the head end, or even further up the chain from the NTU. The content analyzer may also be a part of an existing piece of equipment and would merely involve reprogramming that equipment to perform additional functions, which will be discussed in more detail later. 
     One embodiment of a content analyzer is shown in  FIG. 3 . The content analyzer has a port  36  operable to receive use pattern packets from the various NTUs. The decoder  34  would decode the use pattern packets, in accordance with the content discovery protocol. The content discovery protocol identifies the order and information contained in the payload data, as well as the header. This allows the decoder to ‘unpack’ the payload data and reconstruct the use patterns or services available information or services available information stored and sent by the NTUs. Within that data will also be some sort of identifier to identify the NTU. For example, in current cable systems, set-top boxes each have their own specific Ids, allowing the cable companies to track costs and provide service. In some systems, the NTU may be similar to a network address, such as an IP address. 
     Once the data is decoded, the content analyzer will analyze the data. This will typically be done using a processor, although the definition of processor as used here includes microcontrollers, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), and the like. The analysis of the data will allow the analyzer to characterize the NTU from which the data was received. The content analyzer or other devices in the distribution network may use the characterization to target content to that NTU, and through that NTU to the user. The content may include programs, advertising, or other types of information that can be inserted into the content signals. 
     In addition to tracking the use patterns or services available information of a particular user or viewing device, the NTU could also serve as a quality control for the video distribution network. For example, using the TSID example mention previously, the NTU could determine which programs were reaching the NTU, as well as if all of the packets are arriving properly. This would have a further benefit of allowing advertisers to track if the targeted advertising reached its intended audience, allowing more accurate monitoring of the impact. Knowing that the advertisement has reached its target allows the advertiser to confirm delivery rather than having to estimate how many of the users saw the advertisers. The tracking of this delivery would be formatted into the same packets used to transmit the use patterns. 
     Alternatively, or in addition to, the MPEG transport or other transport protocol for video delivery, the content may include out-of-band signaling. Out-of-band (OOB) signaling is typically used for command and control aspects of the network termination unit. This OOB signaling may be used for enhanced video content, or other services associated with the content delivery. The NTU discovery process may also be used to track and report on usage patterns of these service extensions. This usage will be reported using the same discovery protocol discussed above. 
       FIG. 4  shows one embodiment of a method of forming and transmitting these packets at the NTU. The use patterns or services available information are tracked at  40 . As an optional step the delivery is tracked at  42  as mentioned above. The ‘use’ data referred to here may include the use patterns or services available information and the delivery confirmation data of the video content. This data is then formatted at  44 , into the use pattern packets discussed previously. Again, for ease of decoding this format should conform to the content discovery protocol discussed above. 
     In order to identify the payload data encapsulated in the network packets, the header must be set in accordance with whatever data network is being used for the video distribution network. In most current examples of these networks, the protocol in Internet Protocol. The header is set with the appropriate flag, yet to be determined, that will identify the payload data as content discovery data. Finally, at  48 , the NTU will transmit the packets back to the video distribution network for analysis. 
     As mentioned previously, the content analyzer that receives these packets may be any part of the network that is already currently in existence. A software upgrade to the processor in this piece of equipment would provide the additional instructions necessary to implement the analysis of the use data. Similarly, the set-top boxes and cable modems already in existence may already have the necessary hardware in place. All that is needed is an upgrade to the operating software in those NTUs to allow them to perform the methods of the invention. 
     The invention may be implemented by installing machine-readable code in these NTUs from an article containing the code. The code, when executed, causes the machine to implement the methods of the invention. The machine is some sort of computing device, as defined above, but typically will be a cable modem or set-top box. 
     Thus, although there has been described to this point a particular embodiment for a method and apparatus for content discovery in video distribution networks, it is not intended that such specific references be considered as limitations upon the scope of this invention except in-so-far as set forth in the following claims.