Abstract:
A method of surveying watching image content, and a broadcast receiving apparatus and server employing the same are provided. The method includes displaying image contents on a screen; capturing and storing signature images of the image contents; and in response to receipt of a query, comprising a target image of image contents to be surveyed, from an external server, determining whether one of the stored signature images is identical to the target image, and transmitting a result of the determining to the external server.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATION 
     This application claims priority from Korean Patent Application No. 10-2011-0041700, filed on May 2, 2011 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety, by reference. 
     BACKGROUND 
     1. Field 
     Methods and apparatuses consistent with exemplary embodiments relate to surveying the watching of image content, and more particularly, to method of surveying the watching of image content, based on a technology for recognizing a motion picture or video (also referred to as moving pictures) by extracting a signature image of output image contents, and a broadcast receiving apparatus and server employing the same. 
     2. Description of the Related Art 
     In the past, the major broadcasters were the only source for moving pictures (i.e., motion pictures and/or video). This is no longer the case. Today, moving pictures are available from other sources, including cable, Internet protocol television (IPTV), video-on-demand (VOD), and the like. This diversification of sources for moving pictures has made a very important to develop technologies for recognizing the programs that users watch. Such technologies may serve as the primary basis for a customized advertising campaign, or for program recommendation services. 
     A basic method of surveying whether a user watches image contents is a method of searching a database for metadata that is manually generated based on image contents information (e.g., electronic program guide (EPG) information). However, the approach of using such metadata information is problematic in that there is frequently no access to such metadata information, and in that there may be a substantial dearth of the metadata itself, a situation which may arise due to various local policies of copyright holders or broadcasters. 
     The use of video fingerprints is one alternative to the just-described metadata approach. That is to say, a database is created containing target images of items for which a survey is desired. A signature image of is extracted from a predetermined image source, and the signature image as a query is transmitted to the database. When the database receives the query, whether the signature image is contained in the database is determined, and an identification (ID) of a corresponding image may be obtained. Such technology of moving picture recognition may be referred to as video fingerprint. 
     In the related art, a target image of image contents to be surveyed must be previously extracted so as to build the database, and the database is stored in a server, by using the previously mentioned technology of moving picture recognition. In addition, a broadcasting receiving apparatus extracts signature images from an input image stream, and periodically transmits the signature images to the server. When the server receives the extracted signature image, the server may identify the contents ID by comparing the received signature image with the target image so as to determine whether the user watches the image contents. 
     However, if the above-described alternative approach is used, when moving pictures are generated and transmitted in real time, as in a live broadcast, it is impossible to previously extract a target image and reflect the target image to database, necessitating advanced technologies such as updating the program database in real time. 
     In addition, since it is impossible for the broadcasting receiving apparatus to recognize ahead of time when an audience rating survey or advertising exposure survey is required, the broadcasting receiving apparatus needs to continue to periodically extract signature images and transmit the signature images to the server. That is to say, under this approach, it is necessary to process content even though no survey may ultimately be required, thus wasting network resources. 
     Moreover, under this alternative approach, even if the size of a signature image is small, when the number of broadcasting receiving apparatuses on which an audience rating survey is to be performed is several to tens of millions, excessive server load and excessive maintenance fee may result. 
     SUMMARY 
     Exemplary embodiments provide a method of surveying watching image content, and a broadcast receiving apparatus and server employing the same. 
     According to an aspect of an exemplary embodiment, there is provided a method of surveying the watching of image content output from a broadcast receiving apparatus, the method including outputting input image contents on a screen; capturing and storing a signature image of the image contents output on the screen; and when a query including a target image of the image contents to be surveyed is received from an external server, surveying whether there is a signature image identical to the target image, and transmitting a survey result to the external server. 
     The query may further include a timestamp of when the target image is captured. 
     The surveying may include setting a search period with reference to the timestamp included in the query; and surveying whether there is a signature image identical to the target image from among signature images captured within the search period. 
     A start point of the search period may be set based on a difference between a timestamp of the target image included in the query and a system timestamp measured by the broadcast receiving apparatus when the query arrives at the broadcast receiving apparatus. 
     The time information included in the timestamp may be based on Greenwich Mean Time (GMT). 
     The query may further include contents identification (ID) of the image contents, and the transmitting may include transmitting the survey result together with the contents ID of the image contents. 
     The storing may include storing the signature image in a queue having a predetermined size. 
     The query may be received within a predetermined period of time after the image contents are output, and the predetermined period of time may be determined by the size of the queue. 
     The image contents may include at least one of broadcast contents, advertising contents, and VOD contents. 
     According to an aspect of another exemplary embodiment, there is provided a broadcast receiving apparatus including an output unit for outputting input image contents on a screen; an extracting unit for extracting a signature image from the output image contents; a storage unit for storing the extracted signature image; a communication unit for communicating with an external server; and a controller for, when a query including a target image of the image contents to be surveyed is received from an external server, controlling the communication unit to survey whether there is a signature image identical to the target image, and to transmit a survey result to the external server. 
     The query may further include a timestamp that is time information about a point of time when the target image is captured. 
     The controller may set a search period with reference to the timestamp included in the query, and surveys whether there is a signature image identical to the target image from among signature images captured within the search period. 
     A start point of the search period may be set based on a difference between a timestamp of the target image included in the query and a system timestamp measured by the broadcast receiving apparatus when the query arrives at the broadcast receiving apparatus. 
     The time information included in the timestamp may be based on Greenwich Mean Time (GMT). 
     The query may further include contents ID of the image contents, and the controller may control the communication unit to transmit the survey result together with the contents ID of the image contents. 
     The storage unit may store the signature image in a queue having a predetermined size. 
     The communication unit may receive the query within a predetermined period of time after the image contents are output, and the predetermined period of time may be determined by the size of the queue. 
     The image contents may include at least one of broadcast contents, advertising contents, and VOD contents. 
     According to an aspect of another exemplary embodiment, there is provided a method of surveying the watching of image content of a server, the method including extracting a target image of image contents to be surveyed; generating a query including the target image and a timestamp of the target image, wherein the timestamp indicates a point of time where the target image is captured; transmitting the query to a plurality of broadcast receiving apparatuses; and receiving information about whether the image contents are watched, from the plurality of broadcast receiving apparatuses. 
     The transmitting may include dispersively transmitting the query to the plurality of broadcast receiving apparatuses for a predetermined period of time. 
     The query may further include contents ID of the image contents to be surveyed. 
     According to an aspect of another exemplary embodiment, there is provided a server for surveying whether image contents output from a plurality of broadcast receiving apparatuses, the server including an extracting unit for extracting a target image of image contents to be surveyed; a query generating unit for generating a query including the target image and a timestamp of the target image, wherein the timestamp indicates a point of time where the target image is captured; and a communication unit for transmitting the query to a plurality of broadcast receiving apparatuses and for receiving information about whether the image contents are watched, from the plurality of broadcast receiving apparatuses. 
     The communication unit may dispersively transmit the query to the plurality of broadcast receiving apparatuses for a predetermined period of time. 
     The query may further include contents identification (ID) of the image contents to be surveyed. 
     According to an aspect of another exemplary embodiment, there is provided a method of surveying the watching of image content output from a broadcast receiving apparatus, the method including extracting a signature image of input image contents and storing the signature image in a signature queue; when a query including target signature of image contents to be surveyed is received from an external server, surveying whether there is a signature identical to the target signature in the signature queue; and when it is determined that there is the signature identical to the target signature once or more, performing a predetermined additional process. 
     The query may further include a timestamp that is time information about a point of time when the target image is captured. 
     The query may further include a program to be executed in the broadcast receiving apparatus, an identifier of a corresponding program, or a universal resource locator (URL) of a predetermined Internet resource, and the performing of the predetermined additional process may include executing the program or accessing the predetermined Internet resource through the URL. 
     According to an aspect of another exemplary embodiment, there is provided a broadcast receiving apparatus including an output unit for outputting input image contents on a screen; an extracting unit for extracting a signature from the output image contents; a storage unit for storing the extracted signature in a signature queue; a communication unit for communicating with an external server; and a controller for, when a query including target signature of image contents to be surveyed is received from an external server, surveying whether there is a signature identical to the target signature in the signature queue, and for, when it is determined that there is the signature identical to the target signature once or more, performing a predetermined additional process. 
     The query may further include a timestamp that is time information about a point of time when the target image is captured. 
     The query may further include a program to be executed in the broadcast receiving apparatus, an identifier of a corresponding program, or a universal resource locator (URL) of a predetermined Internet resource, and when it is determined that there is the signature identical to the target signature once or more, the controller executes the program or accesses the predetermined Internet resource through the URL. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects will become more apparent by describing in detail exemplary embodiments with reference to the attached drawings in which: 
         FIG. 1  is a diagram of a system for surveying the watching of image contents, according to an exemplary embodiment; 
         FIG. 2  is a block diagram of the broadcast receiving apparatus according to an exemplary embodiment; 
         FIG. 3  is a block diagram of a server according to an exemplary embodiment; 
         FIG. 4  is a flowchart of a method of surveying the watching of image contents of a broadcast receiving apparatus, according to an exemplary embodiment 
         FIG. 5  is a flowchart of a method of surveying the watching of image contents of the server  200 , according to an exemplary embodiment; and 
         FIG. 6  is a flowchart of a method of surveying the watching of image contents of a system for surveying the watching of image contents, according to an exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, exemplary embodiments will be described in detail with reference to the attached drawings. 
       FIG. 1  is a diagram of a system  10  for surveying the watching of image contents, according to an exemplary embodiment. Referring to  FIG. 1 , the system  10  includes a plurality of broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n, and a server  200 . 
     The broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n receive image contents input to the broadcast receiving apparatuses from various input sources (e.g., a terrestrial broadcaster, a satellite broadcaster, or a cable broadcaster). The broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n perform signal-processing on the image contents that a user wants to watch, and then display the signal-processed image contents for viewing. 
     The broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n extract and store signature images of image contents that are currently output. Here, “the signature images of the image contents” refers to images that are captured from the image contents at a predetermined frequency. The signature images may be stored in a signature queue having a predetermined size. 
     A server  200  extracts the target images from the image contents according to a set of instructions, which may for example be specified by a broadcaster. Here, “target images” refers to images captured from image contents about which the broadcaster wants to perform an audience rating survey or similar survey. 
     In addition, the server  200  generates a query including the extracted target image and a timestamp of the target image. In this case, the timestamp of the target image may contain time information based on a point of time when the target image is captured. The time information may be based on Greenwich Mean Time (GMT) which serves as a universal time without respect to time zone or region. In addition, the query may include an identifier (referred to hereafter as a “contents identification (ID)”) of the image contents. 
     The server  200  transmits the query to the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n. In this case, the server  200  dispersively transmits the query to a predetermined number of broadcast receiving apparatuses from among the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n at staggered times, instead of simultaneously transmitting the query to all the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n, in order to prevent replies to the server  200  from flooding the server. 
     In this exemplary embodiment, since the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n store the signature images in the signature queue having a predetermined size, the server  200  does not have to transmit the query at the instant or at the same time the image contents are output, but may transmit the query after the image contents are output. 
     The broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n determine whether there is a signature image that is identical to the target image that was included in the received query. The broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n set a search period with respect to the queue by using the timestamp of the target image included in the received query, and then survey whether there is a signature image among the signature images that are captured within the search period, identical to the target image. 
     The broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n transmit, to the server  200 , respective survey results about whether there is found a signature image that is identical to the target image that was included in the received query. When sending the survey results, the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n may transmit the contents ID included in the query together with the survey result. 
     When a plurality of survey results sent by the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n are received by the server  200 , the server  200  collects the survey results, and processes information about the audience rating of image contents, advertising exposure, and user preferred contents. 
     The above-described system for surveying the watching of image contents may be effectively used for an audience rating survey of real-time image contents, an advertising exposure survey, or the like. In addition, since a broadcast receiving apparatus and a server are connected to each other only when a survey is required, the search load is prevented from being excessively concentrated on the server. Additionally, since the broadcast receiving apparatus does not have to continue to transmit a signature image, the server load may be remarkably reduced. 
     Hereinafter, with reference to  FIGS. 2 and 3 , a broadcast receiving apparatus  100  and a server  200  will be described in more detail. 
       FIG. 2  is a block diagram of the broadcast receiving apparatus  100  according to an exemplary embodiment. Referring to  FIG. 2 , the broadcast receiving apparatus  100  includes an image input unit  110 , an image processing unit  120 , an image output unit  130 , an extracting unit  140 , a storage unit  150 , a communication unit  160 , and a controlling unit  170 . These various units may be implemented as particular hardware or as software running on a general purpose computer processor such as a CPU or the like, the software being accessed for execution from a random access memory or the like. 
     The image input unit  110  receives and demodulates signals transmitted from various input sources such as a terrestrial broadcaster, a satellite broadcaster, or a cable broadcaster, sent through wired or wireless communication networks. In addition, the image input unit  110  may be connected to an external device, and may receive an image signal from the external device. For example, the image input unit  110  may receive the image through S-Video, component, composite, D-subminiature (D-Sub), digital video interactive (DVI), high definition multimedia interface (HDMI), or the like. 
     The image processing unit  120  may perform signal processing, such as video decoding or video scaling on an input broadcast signal or on an image signal, and may add graphic user interfaces (GUIs). 
     The image output unit  130  receives image contents that have been signal-processed by the image processing unit  120 , and outputs the image contents to be displayed on a display screen. 
     The extracting unit  140  extracts a signature image based on the image contents output from the image output unit  130 . In this case, the signature image may be an image captured from the output image contents, but this is just an example. Alternatively, the signature image may be a partial image (e.g., a logo, or the like) contained in an image of the output image contents, or may be a signature of the image of the output image contents. In addition, the image contents may be broadcast contents, advertising contents, or video on demand (VOD) contents. 
     In particular, the extracting unit  140  may extract the signature image of the image contents output by the image output unit  130  at a predetermined frequency. For example, the extracting unit  140  may extract the signature image of the image contents output by the image output unit  130  at a frequency corresponding to 0.5 seconds. In particular, since the extracting unit  140  extracts the signature image at a frequency corresponding to a short period of time, it is possible to determine whether the image contents such as advertising, which have a short broadcast period of time, are watched. 
     The storage unit  150  may store various programs required to operate the broadcast receiving apparatus  100 , and may be a memory, a hard disk drive (HDD), or the like. 
     In particular, the storage unit  150  stores the signature image extracted by the extracting unit  140  in a signature queue. The queue may be an ordered list having one end in which data is inserted and another end in which data is deleted, and may be referred to as a first in first out (FIFO) ordered list. 
     In this exemplary embodiment, the signature queue may have a predetermined size so as to store a predetermined number of signature images. For example, if one signature image corresponds to 100 bytes, the signature queue may have a size of about 1.4 Mb in order to store 14400 signature images. Here, if the extracting unit  140  captures two signature images every second, the signature queue may store signature images of image contents corresponding to 7200 seconds, that is, 2 hours. 
     The communication unit  160  is connected to the server  200  through a network, and transmits and receives data to and from the server  200 . In detail, the communication unit  160  may receive a query, including a target image and a timestamp of the target image from the server  200 . The query may further include the contents ID of the image contents, as well as an indication of a subsequent action to be taken. The indication of the subsequent action to be taken may include a variety of things, such as, for example, a program to be executed in a broadcast receiving apparatus, an identifier of a corresponding program, or a universal resource locator (URL) of the Internet resource. 
     In addition, the communication unit  160  may transmit, to the server  200 , a survey result about whether there is found a signature image identical to the target image. 
     The controlling unit  170  controls an overall operation of the broadcast receiving apparatus  100  according to a user command received from a user input unit (not shown). 
     In particular, when the controlling unit  170  receives the query including the target image of the image contents for which a survey of the level of viewership is being carried out, from the server  200 , outside the broadcast receiving apparatus  100 , the controlling unit  170  determines or “surveys” whether there is in the signature queue of the storage unit  150  a signature image identical to the target image. 
     In this exemplary embodiment, the controlling unit  170  may set a search period of the queue by using the timestamp of the target image included in the received query, and may determine whether there is, contained among the signature images corresponding to the search period of the set queue, a signature image identical to the target image. 
     In this case, a start point of the search period may be set based on a difference between the timestamp of the target image, included in the query, and a system timestamp measured, by the broadcast receiving apparatus  100 , when the query arrives at the broadcast receiving apparatus  100 . For example, if the timestamp of the target image is 7 PM, and the system timestamp measured by the broadcast receiving apparatus  100  is 8:30 PM, a difference between the timestamp of the target image and the system timestamp measured by the broadcast receiving apparatus  100  when the query arrives at the broadcast receiving apparatus  100  is 1 hour and 30 minutes. Thus, the controlling unit  170  may set a point of time before 1 hour and 30 minutes from an end point of the signature queue as the start point of the search period. In addition, the controlling unit  170  may search for signature images contained in a predetermined period (e.g., 3 minutes) from the start point of the search period, which is calculated as described above. 
     If there is a signature image identical to the target image in the search period of the signature queue, the controlling unit  170  may generate survey result information indicating that a user has viewed the corresponding image contents, and may control the communication unit  160  to transmit the survey result information to the server  200 . 
     However, if there is no signature image identical to the target image found during the search period for the signature queue, the controlling unit  170  may generate survey result information indicating that the user did not view the corresponding image contents, and may control the communication unit  160  to send negative survey result information to the server  200 . 
     When the survey result information is transmitted, if a contents ID is included in the query received from the server  200 , the controlling unit  170  may transmit the contents ID of the image contents together with the survey result information. 
     As a survey result, if the controlling unit  170  determines that the signature image is identical to the target image once or more than once, a predetermined additional process may be performed. For example, the controlling unit  170  may execute a program included in the query, or may access a predetermined Internet resource through a URL of the Internet resource included in the query. 
     When a survey is conducted as to whether image contents are viewed, by the broadcast receiving apparatus  100 , a broadcaster may survey and audience rating of broadcasting contents, and survey the advertising exposure by processing information about whether the image contents are watched. In addition, preferred user content may be identified through information about whether the image contents are watched, thereby providing information as to what image contents might be appropriate to display to a user for advertising or the like. For example, the broadcaster may identify the user&#39;s preferred contents through the survey result information, thereby enabling customized advertising or image contents recommending services. 
       FIG. 3  is a block diagram of a server  200  according to an exemplary embodiment. Referring to  FIG. 3 , the server  200  includes an extracting unit  210 , a query generating unit  220 , a communication unit  230 , and a controlling unit  240 . 
     The extracting unit  210  extracts a target image of the image contents provided by a broadcaster. In this case, the target image refers to a predetermined image of the image contents on which the broadcaster wants to conduct the survey as to whether the content is being viewed. In this case, the extracting unit  210  may include a separate storage unit (not shown) for storing the target image. 
     The query generating unit  220  generates a query by using the target image extracted by the extracting unit  210  and a timestamp of when the target image is extracted. In this case, the timestamp may be based on Greenwich Mean Time (GMT) which is the time zone that is universal and without respect to different geographic locations. In addition, the timestamp may be based on Universal Time Coordinated (UTC) which is another standard universal time. 
     In this case, the generated query may further include a contents ID of the image contents, a program to be executed in a broadcast receiving apparatus, an identifier of a corresponding program, or a URL of the Internet resource. 
     The communication unit  230  is connected to the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n through a network, and transmits and receives data to and from the receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n. In detail, the communication unit  230  may transmit the query generated by the query generating unit  220  to the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n. The communication unit  230  may dispersively transmit the query to a predetermined number (i.e., a subset) of broadcast receiving apparatuses from among the entire set broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n with a time lag, instead of simultaneously transmitting the query to all the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n. For example, if the number of the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n is ten million, the communication unit  230  may transmit the query to a million broadcast receiving apparatuses at a frequency corresponding to a certain number of apparatuses every 10 minutes. Thus, even when 100 minutes as a delay time elapse after the communication unit  230  outputs image contents, it is still possible to determine whether the image contents were viewed. In this case, the delay time of the communication unit  230  may be determined according to a size of the signature queue stored in the broadcast receiving apparatus  100 . That is, if the size of the signature queue corresponds to a size for storing signature images of the image contents corresponding to two hours, the delay time of the communication unit  230  may be a maximum of 2 hours. 
     In addition, the communication unit  230  may receive survey result information (that is, information as to whether image contents are watched) related to the target image from the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n. In this case, as described above, when the query is not simultaneously transmitted to all of the stations at once, the communication unit  230  may dispersively receive survey result information from a predetermined number of broadcasting receiving apparatuses from among the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n with a time lag, instead of simultaneously receiving the survey result information of the target image from the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n. 
     The controlling unit  240  receives a user command through a user input unit (not shown), and controls an overall operation of the server  200 . 
     In particular, the controlling unit  240  collects the survey result information of the target image that is received through the communication unit  230  so as to perform an audience rating survey of corresponding image contents or an advertising exposure survey. 
     Since a survey as to whether broadcasted contents are being viewed may be undertaken by the server  200 , a broadcaster may reduce costs for the server  200 , and may perform an audience rating survey on image contents that are broadcast for even a short period of time, such as whether a particular advertisement is being viewed. 
     Hereinafter, with reference to  FIGS. 4 through 6 , a surveying method of watching of the image contents will be described.  FIG. 4  is a flowchart of a method of surveying the watching of image contents of the broadcast receiving apparatus  100 , according to an exemplary embodiment. 
     The broadcast receiving apparatus  100  receives image contents through various input sources (S 410 ). In this case, examples of the input sources may include Internet protocol television (IPTV) and video on demand (VOD) as well as a terrestrial broadcaster, a satellite broadcaster, and a cable broadcaster. 
     The broadcast receiving apparatus  100  displays the received image contents (S 420 ). 
     When the image contents are displayed, the broadcast receiving apparatus  100  captures a signature image by using the displayed image contents (S 430 ). In this instance, the broadcast receiving apparatus  100  may capture signature images of the displayed image contents at a predetermined frequency (e.g., two signature images every second). 
     When a signature image is captured, the broadcast receiving apparatus  100  stores the captured signature image in a queue (S 440  The queue may have a predetermined size so as to store the signature images of the image contents, which are captured at a predetermined frequency. For example, if one signature image corresponds to 100 bytes, and two signature images are captured every second, the broadcast receiving apparatus  100  may have a queue that is about 1.4 Mb in order to store enough signature images for about a 2 hours period. 
     When the broadcast receiving apparatus  100  receives a query from the server  200  which is outside the broadcast receiving apparatus  100  (S 450 ), the broadcast receiving apparatus  100  surveys whether there is a signature image identical to a target image included in the query (S 460 ). 
     In detail, the broadcast receiving apparatus  100  sets a search period of the queue by using a timestamp of the target image included in the query, and surveys whether there is, among the signature images in the queue, an image identical to the target image. In this case, the start point of the search period may be set based on a difference between a timestamp of the target image included in the query and a system timestamp measured by the broadcast receiving apparatus  100  when the query arrives at the broadcast receiving apparatus  100 . 
     In addition, the broadcast receiving apparatus  100  transmits, to the server  200  outside the broadcast receiving apparatus  100 , a survey result about whether there is the signature image identical to the target image included in the received query (S 470 ). 
       FIG. 5  is a flowchart of a method of surveying the watching of image contents of the server  200 , according to an exemplary embodiment. 
     First, the server  200  extracts a target image of the image contents (S 510 ). In this case, the target image refers to a predetermined image of the image contents on which a broadcaster wants to survey whether to watch. 
     When the target image is extracted, the server  200  generates a query by using the target image and a timestamp of the target image (S 520 ). In this case, the timestamp of the target image may contain time information about a point of time when the target image is captured. The time information may be based on Greenwich Mean Time (GMT), UTC, or the like. T In addition, the query may include contents identification (ID) of the image contents. 
     When the query is generated, the server  200  transmits the generated query to the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n (S 530 ). In this case, the server  200  dispersively transmits the query to a predetermined number of broadcast receiving apparatuses from among the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n with a time lag, instead of simultaneously transmitting the query to all the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n. For example, if the number of the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n is ten million, the server  200  may transmit the query to a million broadcast receiving apparatuses every 10 minutes. In this case, a delay time by which the server  200  delays transmitting the query may be determined according to a size of the queue of the broadcast receiving apparatus  100 . 
     In addition, the server  200  receives information about whether the image contents are watched, from the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n (S 540 ). In this case, the server  200  may dispersively receive survey result information about whether image contents are watched from a predetermined number of broadcasting receiving apparatuses from among the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n with a time lag, instead of simultaneously receiving the survey result information of the target image from the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n. As described above, if the server  200  may receive the survey result information from a predetermined subset of receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n with a time lag, thereby reducing the load of the server  200 . 
     When the server  200  receives the survey result information, about whether image contents are watched, from the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n, the server  200  collects the survey result information from the broadcast receiving apparatuses  100 - 1 , 100 - 2 , through  100 -n, and processes the survey result information. For example, if the image contents are broadcast contents, the server  200  may perform an audience rating survey on the contents through survey result information of the broadcast contents. If the image contents are advertising contents, the server  200  may gauge the advertising exposure through the survey result information related to the advertising contents. 
     In addition, the server  200  may identify the kind of content that a user prefers to view from the survey result information thereby enabling the providing of customized advertising to user. 
       FIG. 6  is a flowchart of a method of surveying the watching of image contents of the system  10 , according to an exemplary embodiment. 
     First, the broadcast receiving apparatus  100  receives image contents through various sources (S 610 ), and displays the image contents (S 620 ). The broadcast receiving apparatus  100  captures signature images of the displayed image contents at a predetermined frequency, and stores the signature images (S 630 ). In this case, the signature image may be stored in a signature queue having a predetermined size. 
     In addition, the server  200  extracts a target image from the image contents for which a broadcaster wants to survey (S 615 ). In addition, the server  200  generates a query by using the target image and a timestamp of the target image (S 625 ). 
     In addition, the server  200  transmits the generated query to the broadcast receiving apparatus  100  (S 640 ). 
     The broadcast receiving apparatus  100  surveys whether there is a signature image identical to the target image by using the received query (S 650 ). In detail, the broadcast receiving apparatus  100  sets a search period of the queue by using the timestamp of the target image included in the received query, and then surveys whether there is the signature image identical to the target image from among the signature images previously captured and corresponding to the search period. 
     Once the processing of all the signature images has been completed, the broadcast receiving apparatus  100  transmits a survey result, that is, information about whether image contents are watched, to the server  200  (S 660 ). 
     In addition, the server  200  determines whether the image contents are watched, by using the transmitted survey result (S 670 ). 
     When a determination as to whether image contents are viewed is carried out as described with reference to  FIGS. 4 through 6 , it is not necessary to determine whether the image contents are viewed at the same time that the image contents are being displayed. In this case, even if moving pictures are generated and transmitted in real time, such as is the case in a live broadcast, a determination as to whether the image contents are being viewed may still be correctly determined. 
     Since signature images are extracted at a frequency corresponding to a short period of time (e.g., two signature images every second), it is possible to make a determination as to whether relatively short broadcast time periods are viewed, such as periods corresponding to advertising. 
     Also, since the server  200  dispersively transmits and receives data to and from a predetermined number of broadcast receiving apparatuses, instead of simultaneously transmitting and receiving data to and from millions to tens of millions of broadcast receiving apparatuses, the load of the server  200  is spread out, and thus a broadcaster may reduce costs for the server  200 . That is to say, it becomes less necessary for a server  200  to have the capability to process the transmitting and receiving of data for all of the apparatuses simultaneously and this means that a less expensive server may be used. 
     The broadcast receiving apparatus  100  may be a TV, but this is just an example. That is, the broadcast receiving apparatus  100  may be any electronic device adapted to receive a broadcast. For example, the broadcast receiving apparatus  100  may be a personal computer (PC), a smart phone, a tablet PC, or the like. Moreover, even though the term “broadcast” has been used, it will be understood that the term is meant to encompass the transmission of motion picture or video data through any means. 
     While exemplary embodiments have been particularly shown and described, it will be understood by those of ordinary skill in the art that various changes in form and detail may be made without departing from the spirit and scope of the inventive concept as defined by the following claims.