Patent Publication Number: US-2022238140-A1

Title: Video tagging device and video tagging method

Description:
TECHNICAL FIELD 
     The present invention relates to a video tagging device and method for appending (or tagging) to a video footage tags and/or comments that have been input while seeing a video recording subject of the video instead of watching video footage. 
     BACKGROUND ART 
     Conventionally, in a sports game or practice, for example, videos have been recorded using smartphones, tablets, capture devices, etc., to coach or analyze the players using those videos. On that occasion, the recorded video data are often tagged with a particular scene such as a goal scene. Coaches or others instructing players retrieve desired scenes from tagged footage to provide the players with feedbacks. An analyst retrieves a desired scene from the tagged footage to prepare an analysis report. 
     Other typical conventional methods for tagging a video include those that load video data into a personal computer to perform tagging scene-by-scene while playing the video. Among such methods, patent document 1, for example, proposes a video tagging that is performed by independently preparing metadata that contain a pair of time data at which an event occurs and information on a type of the event, and appending that metadata to a tag-unadded recorded video. 
     PRIOR ART DOCUMENTS 
     Patent Documents 
     Patent document 1: JP-A-2008-5010 
     SUMMARY OF THE INVENTION 
     Problems to be Solved by the Invention 
     However, in a conventional video tagging method as mentioned above, tagging work needs to be done only after the recording of a video has been completed, and on top of that, the tagging needs to be done all by oneself and takes time. For this reason, there has been a problem that it takes time before a tagged video becomes available for coaches or analysts to check Further, coaches or analysts need to prepare a report or to provide players with feedback, in association with a scene in a recorded video, about what they felt or noticed during a match or practice. However, if the tagging is made by others, it takes time to even find such scene. Furthermore, coaches or analysts may potentially forget about what they felt or noticed from the scene they actually saw even by watching a video footage after the tagging had been made. 
     If coaches or analysts are able to tag a video by themselves with what they felt or noticed from the scene they actually saw on a real-time basis, the above-mentioned problems would be solved. Nevertheless, in the case where the video recording device and the tagging device are different from each other, if video data are uploaded to a server via a communication network, playback of the video from the server (live streaming) lags several tens of seconds behind the actual time (absolute time) due to video image processing such as encoding or communication time period. Further, as is the same case for an un-tagged recorded video of patent document 1, the recorded video data do not contain any data on the absolute time but rather contain data concerning a relative time, associated with the number of frames, as a time that has lapsed from a video recording start time. For this reason, it has never been possible to perform a tagging such that a tag appended time of a tag containing the absolute time of the scene they actually saw is matched up (in synchronization) with the corresponding video recording time. 
     If one attempts to tag video data on a real time basis, unlike conventional methods, there exist no metadata that are appended with, for example, feature quantity information such as those as described in patent document 1 whenever tagging is to be made. Accordingly, if tagging is to be made in real time, unlike patent document 1, one cannot employ a method of matching a feature quantity sequence information, added to the metadata, with a feature quantity sequence information of un-tagged video to detects which time in the event time tag best matches the time in the untagged video data in order to automatically provide an offset time. 
     The present invention has been made in view of such circumstances and provides a video tagging device and a video tagging method that are capable of appending (or tagging) input tags and/or comments to a video footage to be properly synchronized therewith while seeing a video recording subject of the video instead of watching video footage. 
     Means to Solve the Problems 
     The present invention has been made to solve these problems, and provides a video tagging device comprising: 
     a video data acquisition module to acquire video data recorded by a first terminal device from the first terminal device and to acquire a video recording start time at which recording of the video data is started, and then have the video data and the video recording start time stored in a storage device; 
     a tag information acquisition module to acquire tag information having tags and/or comments from a second terminal device when the tag information is generated in the second terminal device, and to acquire a tag information generation time at which the tag information is generated; and 
     an image processing module to append the tag information to the video data at a timing synchronized with the tag information generation time based on the video recording start time stored in the storage device and a lapse of time from which the recording of the video data is started. 
     As for the video tagging device, the tag information acquisition module may be configured to obtain tag information from a plurality of the second terminal devices. 
     As for the video tagging device, the video tagging device may be configured not to transmit the video data, acquired from the first terminal device, to the second terminal device during a period for which the second terminal device is displaying a screen for producing the tag information. 
     The video tagging device may further comprise a video distribution module to distribute a tagged video with the tag information being appended to the video data, wherein the video tagging device is configured not to contain the video recording start time acquired by the video data acquisition module in the tagged video data that are to be distributed from the video distribution module. 
     The video tagging device may further comprise a video distribution module to distribute tagged video data to a third terminal device upon tapping the tag information on the display screen of the third terminal device during a period for which the tagged video data of which the tag information is appended to the video data are being distributed to the third terminal device, wherein the tagged video data to be distributed to the third terminal device contains a timing synchronized with the tag information generation time corresponding to the tag information. 
     The present invention provides a video tagging method comprising: a first step of acquiring video data recorded by a first terminal device from the first terminal device and acquiring video recording start time at which recording of the video data is started; a second step of storing the video data and the video recording start time in a storage device; a third step of acquiring tag information having tags and/or comments from a second terminal device when the tag information having tags and/or comments is generated in the second terminal device, and acquiring a tag information generation time at which the tag information is generated; and a fourth step of appending the tag information to the video data in a timing synchronized with the tag information generation time based on the video recording start time stored in the storage device and a lapse of time from which the recording of the video data is started. 
     As for the video tagging method, the tag information is obtainable in the third step from a plurality of the second terminal devices. 
     As for the video tagging method, the video data acquired from the first terminal device may be not transmitted to the second terminal device during a period for which the second terminal device is displaying a screen for producing the tag information in the third step. 
     The video tagging method may further comprise a fifth step of distributing tagged video data with the tag information being appended to the video data, wherein the video recording start time acquired in the first step is not contained in the tagged video data that are to be distributed in the fifth step. 
     The video tagging method may further comprise a sixth step of distributing tagged video data to a third terminal device upon tapping the tag information on the display screen of the third terminal device during a period for which the tagged video data of which the tag information is appended to the video data are being distributed to the third terminal device, wherein the tagged video data to be distributed to the third terminal device contains a timing synchronized with the tag information generation time corresponding to the tag information. 
     Effects of the Invention 
     According to the video tagging device and the video tagging method of the present invention, video data are acquired from the first terminal device, and video recording start time is also acquired to store them in the storage device to correct the deviation in the playback time of the video data with reference to the actual time based on this video recording start time and a lapse of time from which the video recording of the video data is started in order to append the tag information to the video data at a timing appropriately synchronized with the tag information generation time acquired by the tag information acquisition module. The users are thus capable of tagging tag information, containing tags and/or comments having been input in second terminal device, in correct time synchronization therewith to video data of the live footage that is being streamed in real time while seeing an actual scene that is the video recording subject of the video instead of watching video footage. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram illustrating a preferred embodiment of a schematic framework of a video tagging system comprising a video tagging device of the present invention. 
         FIG. 2  is an explanatory drawing illustrating a preferred embodiment of a method for tagging tags and/or comments to video data according to the video tagging method and the video tagging system having the video tagging device of the present invention. 
         FIG. 3  is a diagram schematically illustrating a preferred embodiment of a display screen when playing a tagged video that has been tagged according to the video tagging method and the video tagging system having the video tagging device of the present invention. 
         FIG. 4  is a flow chart illustrating a preferred embodiment of a processing flow according to the video tagging method and the video tagging system having the video tagging device of the present invention. 
     
    
    
     MODE FOR CARRYING OUT THE INVENTION 
     Preferred embodiments of the video tagging device and the video tagging method according to the present invention will hereunder be described with reference to the drawings. 
       FIG. 1  is a block diagram illustrating an overall configuration of the video tagging system  1  including a video tagging device  4  according to the present embodiment. 
     It contains, as components for achieving the video tagging system  1  according to the present embodiment, a first terminal device  2 , a second terminal device  3 , a server which is a video tagging device  4 , and a communication network  5 . In the figure, only one second-terminal device  3  is illustrated but there may be contained a plurality of second terminal devices  3 . Further, a third terminal device  30  configured in a similar manner as the second terminal device  3  may also be contained therein (see,  FIG. 3 ). 
     The first terminal device  2  includes, as main components, a control unit  21 , a communication module  22 , and a display module  23 . The control unit  21  contains a video recording module  211  that records live scenes to generate video data  421 . The control unit  21  controls the communication module  22  to enable communication via the communication network  5  to the server  4 , the second terminal device  3 , the third terminal device  30  and/or other devices (not shown). In the present embodiment, the communication module  22  is mainly used for the purpose of sending data of a video recording start time  422  to the server  4  for uploading the video data  421  to the server  4  and/or for storing the video recording start time  422  of the video data  421  in a storage device  42  of the server  4 . The control unit  21  controls the display module  23  to display footage of, for example, a recording video on a display screen (not shown) of the display module  23 . For example, portable information terminal devices such as a camera-equipped smartphone or tablet with video recording functionality and a capture device may be used for the first terminal device  2 . 
     The video data  421  are recorded by the video recording module  211  at a frame rate of, for example, 30 or 60 fps and consist of a plurality of frames  71  that are continuous in time series (see  FIG. 2 ). Each frame  71  is associated with a frame time that indicates a lapse of time from which the video recording is started. 
     The second terminal device  3  includes, as main elements, a control unit  31 , a storage device  32 , an input means  33 , a communication module  34 , and a display module  35 . The control unit  31  contains, in a manner to be described later in detail, data on tag information generation time  424  that indicates a time at which, e.g., tags and/or comments are appended, and additionally a tag information generation module  311  for generating tag information  423  containing the tag and/or comment. 
     The storage device  32  contains a program  321  to be stored by, e.g., installation. 
     The control unit  31  reads out a program  321  from the storage device  32 , and the program  321  allows the control unit  31 , serving as a computer, to activate the tag information generation module  311 . The input means is configured to communicate a fact that any one or more tag buttons  61 ,  62 ,  63 , and  64 , shown in  FIG. 2 , are pushed to the control unit  31 , or to communicate data that are input by inputting comments to the control unit  31 . 
     The input means  33  includes entry keys displayed, for example, on a touch screen, and accepts, for example, characters that are input with the keys. If an operation of, for example, tapping the touch screen is carried out, then the control unit  31  reads out the program  321  to carry out an input instruction for the control unit  31  to activate a function associated with the operation thereof. For example, if an operator pushes a button displayed on the touch screen, then the fact that the button is pushed with the input means  33  is communicated to the control unit  31 , and the control unit  31 , in turn, makes the tag information generation module  311  recognize that the button is selected by an instruction of the program  321 . The input means  33  may contain input keys of a keyboard provided in, e.g., a mobile computer. Further, the input means  33  may be a means that receives inputs by a voice which is converted into text data to transmit them to the control unit  31 . 
     The control unit  31  controls the communication module  34  to enable communication via the communication network  5  to the server  4 , the first terminal device  2 , the third terminal device  30  and/or other devices (not shown). 
     The control unit  31  controls the display module  35  to enable a display screen  60  (See  FIG. 2 ) of the display module  35  to display an application or software screen or the like which is generated by the program  321 . The display module  35  and the input means  33  constitute the above-mentioned touch screen, and the input means  33  configured as a transparent electrode is arranged on the display screen of the display module  35 . As for the touch screen, it is configured such that if the input means  33  is operated by touch on, e.g., input keys or buttons displayed on the display module  35 , then the corresponding operation signal is transmitted from the input means  33  to the control unit  31 . 
     The second terminal device  3  comprises the communication module  34  and is a device capable of executing a program  321  to activate an application or software. For example, a portable information terminal device such as a smartphone or tablet terminal and a mobile computer may be used as such device. For example, in the case of carrying out an analysis, a desktop personal computer or the like may be used as a second terminal device  3  for playing and displaying tagged video data  426 . 
     If structurally possible, in order to provide the first terminal device  2 , configured as a video recording terminal, with a function of the second terminal device  3  which is a tagging terminal device, there may be employed a configuration where the first terminal device  2  includes the input means  33  and the tag information generation module  311 . However, it is normally preferable that the first terminal device  2  and the second terminal device  3  are devices different from each other. 
     In the present embodiment, the server  4  configured as a video tagging device of the present invention includes, as main elements, a control unit  41 , a storage device  42  and a communication module  43 . The control unit  41  includes a video data acquisition module  411 , a tag information acquisition module  412 , an image processing module  413 , and a video distribution module  414 . The control unit  41  controls the communication module  43  to enable communication via the communication network  5  to the first terminal device  2 , the second terminal device  3 , the third terminal device  30  and/or other devices (not shown). The communication module  43  is used, according to the present embodiment, for the purpose of receiving the video data  421  transmitted from the first terminal device  2  to upload the video to the server  4 , and/or sending the tagged video data  426  to, for example, the second terminal device  3  and/or the third terminal device  30 . The video data acquisition module  411  of the control unit  41  is configured to have the storage device store the video data  421  uploaded from the first terminal device  2  and data on the video recording start time  422  obtained by, e.g., transmission from the first terminal device  2 . Particularly, with regard to the video recording start time  422 , if the video data acquisition module  411  acquires the video recording start time  422 , at which the recording of the video data  421  is initiated, based on time data which are counted by, for example, a timekeeping means (not shown) integrated in the control unit  21  of the first terminal device  2 , then the video data acquisition module  411  allows the obtained video recording start time  422  to be stored in the storage device  42 . The image processing module  413  of the control unit  41  generates, in a manner to be described later in detail, tagged video data  426  in which tag information  423  is capable of being appended to video data  421  at a timing synchronized with the tag information generation time  424 , and store them in the storage device  42  based on the video recording start time  422 , read out from the storage device  42 , and a lapse of time from which the recording of the video data is started. The video distribution module  414  of the control unit  41  controls the communication module  43  for video streaming the tagged video data  426 , generated by the image processing module  413 , to a video streaming terminal device such as the second terminal device  3  and the third terminal device  30 . 
     The storage device  42  of the server  4  contains a program  427  to be stored by, e.g., installation. Hardware configuration of the server  4  may be a general configuration such that the control unit  41  configured as a computer includes a central processing unit (CPU) which executes a program  427  stored in the storage device  42  such as a ROM (Read Only Memory) and a hard disk. The program  427  instructs the control unit  41 , configured as a computer, to execute the video data acquisition module  411 , the tag information acquisition module  412 , the image processing module  413  and the video distribution module  414 . 
     The communication network  5  is a communication infrastructure such as the internet. 
     There will be described a video streaming by the video distribution module  414  of the server  4 , particularly about live streaming for streaming the tagged video data  426  as a video image on a real-time basis with reference to  FIG. 2 . 
     First, the first terminal device  2  starts the recording of a video at 18:55. The control unit  21  of the first terminal device  2  controls the communication module  22  to upload video data  421  to the server  4  via the communication network  5 . The control unit  41  of the server  4  controls the communication module  43  to receive the video data  421 , which are then stored in the storage device  42 . In this period, a few seconds (normally 15 to 30 seconds) are passed since the video recording is started because of the period during which the video processing is performed for, e.g., encoding the video data  421  and communication period. As this lagged time varies depending on the performance of the first terminal device  2  and the server  4  or the situation or environment of the communication network  5 , one cannot predict or estimate any specific lagged time to use it as a time gap for synchronizing the time. 
     According to the video tagging method and the video tagging system  1  having a video tagging device  4  of the present embodiment, at the outset of uploading video data  421  from the first terminal device  2  to the server  4 , time data, counted by, for example, a timekeeping means (not shown) that is integrated into the control unit  21  of the first terminal device  2 , are uploaded, along with the video data  421 , as a video recording start time  422  at which the recording of the video data  421  is initiated by the first terminal device  2 . The video data acquisition module  411  contained in the control unit  41  of the server  4  allows time data of this video recording start time  422  to be stored in the storage device  42 . The image processing module  413  sets the start time of the video data  421  stored in the storage device  42  to be a video recording start time  422  stored in the storage device  42 . The video distribution module  414  starts streaming at T 0  to which 18:55, a time at which the actual video recording is started, is allocated. The line indicated as TL is a timeline indicating a timecourse of the streaming live footage, and the time noted in each bracket indicates the absolute time that is associated with the video data  421 . The times as indicated in these brackets lag, e.g., 15 to 30 seconds behind the times at which the scenes corresponding to the times indicated in the brackets are actually streamed. 
     There is no particular limitation to the manner by which how the video recording start time  422  is acquired as long as there can be obtained the absolute time at which the recording of the video data  421  is started. For example, the video recording start time  422  may be acquired from time data which are counted by, for example, a timekeeping means (not shown) integrated in the control unit  41  of the server  4 . In this case, for example, the video data acquisition module  411  of the control unit  41  separately receives from the first terminal device  2  a fact that the recording has started, and the time data at that time made by a timekeeping means of the server  4  are stored in the storage device  42  as a video recording start time  422  at which the recording of the video data  421  is started by the first terminal device  2 . Further, the video recording start time  422  may be acquired from time data which are counted by other timekeeping means (not shown). 
     The video data  421  recorded by the first terminal device  2  do not contain any data relating to the above-mentioned absolute time (the time indicated in the bracket on the timeline TL). The video data  421  only contain data relating to a relative time which is a time that has lapsed from the video recording start time  422 . That is, as explained above, each of the frames  71  in the video data  421  is associated with a frame time that indicates a lapse of time from which the recording is started. Accordingly, this frame time may be added to the video recording start time  422  that is stored in the storage device  42  of the server  4  to estimate actual times (absolute times) at which the respective frames  71  are recorded. As illustrated in an example of  FIG. 2 , in the case where the streaming start time T 0  is set at 18:55 that is a video recording start time  422 , while 5 minutes is, for example, set as a frame time that is a time that has lapsed before T 1  at which the game is started, these 5 minutes may be added to 18:55 to estimate that the game is started at 19:00. In this way, video data  421  having no absolute time may be associated with a time at which the actual video recording took place. 
     The image processing module  413  of the server  4  may append the recorded times estimated as shown above, i.e., data on the actual recorded times (absolute time), to the video data  421  stored in the storage device  42  to store them in the storage device  42 . For example, the data on the appended actual recorded time (absolute time) are associated with the respective frames  71 , and may be used as identification information  425  of the frames  71 . 
     It should be noted that the size of the frames  71  shown in  FIG. 2  is illustrated merely for explanatory purpose, and the positional relationship between the timescale and position of the frames  71  is different from the actual one. 
     In  FIG. 2 , the line indicated as TR is a timeline that indicates actual time, i.e., a timeline indicating a timecourse of the actual game. Here, game starting time is set at 19:00. At 19:15 as indicated next to it in the timeline TR, a user A who owns a second terminal device  3  that is a device different from the first terminal device  2  recording the video data  421 , operates the input means  33  on the display screen  60  for an application or software which is displayed on the display module  35  of the second terminal device  3  in order to tag comments and/or tags. In the meantime, the user A performs operation of the input means  33  of the second terminal device  3  not by watching live footage of the video data  421  which is live streaming on a real-time bases but rather by watching an actual game scene that is actually taking place in reality. Accordingly, coaches or analysts are able to take advantage of the second terminal device  3  to tag, by themselves, what they felt or noticed at the scenes they actually saw on a real-time basis. 
     At 20:10 on the timeline TR, a user B different from the user A is performing operation of the input means  33  of a second terminal device  3 ′ for tagging comments and/or tags. In a similar way, at 20:20, a user C is performing operation of the input means  33  of a second terminal device  3 ″ for tagging comments and/or tags. For example, the user A is a coach, the user B is a defense analyst, and the user C is an offence analyst. A plurality of users A, B and C may simultaneously use the second terminal devices  3 ,  3 ′,  3 ″ to tag comments and/or tags although their focuses vary depending on their responsibility. Further, as they tag by themselves, they may easily retrieve a desired scene by displaying the tagged video data  426  distributed from the video distribution module  414  via the communication network  5  to the second terminal device  3  to retrieve the scene from them. 
     In this way, the tag information acquisition module  412  integrated in the control unit  41  of the server  4  is configured to obtain tag information from each of the plurality of second terminal devices  3 ,  3 ′,  3 ″ via the communication network  5 . Further, in order to prevent the users A, B and C from tagging in a wrong timing while watching not an actual game scene but live footage on the second terminal devices  3 ,  3 ′,  3 ″ they own, the video distribution module  414  in the server  4  is configured such that the video data  421  obtained from the first terminal device  2  are prevented from being distributed via a communication network  5  to the second terminal devices  3 ,  3 ′,  3 ″ in a period during which the tagging display screens  60 ,  60 ′,  60 ″ used to generate the tag information shown in  FIG. 2  are displayed on the display module  35  of at least the second terminal devices  3 ,  3 ′ and  3 ″. 
     Operation of the video tagging system  1  having the video tagging device  4  according to the present embodiment will be specifically described for the case where the second terminal devices  3 ,  3 ′,  3 ″ owned by the users A, B and C are operated for tagging tags and/or comments. 
     As for the display screens  60 ,  60 ′,  60 ″ of the second terminal devices  3 ,  3 ′,  3 ″, the control unit  31  reads out the program  321  stored in the storage device  32  to activate an application or software to display on the display module  35 : tag buttons that can be pushed with the input means  33  when appending tags, and contain a “tag 1” button  61 ,  61 ′,  61 ″, a “tag 2” button  62 ,  62 ′,  62 ″, a “tag 3” button  63 ,  63 ′,  63 ″ and a “tag 4” button  64 ,  64 ′,  64 ″; a “Comment” field  65 ,  65 ′,  65 ″ that allows comments to be input when appending the comment; and a “register button”  66  that can be pushed when determining an appendment of tags and/or comments. 
     In the second terminal device  3 , if the control unit  31  is informed of a fact that the “tag 1” button  61 , for example, is pushed with the input means  33 , then the control unit  31  makes the tag information generation module  311  recognize that “tag 1” button  61  is selected based on an instruction of the program  321 . If the control unit  31  is informed of a fact that the “Register” button  66  is pushed with the input means  33  at the time when the “tag 1” button  61  is selected, then the control unit  31  makes the tag information generation module  311  recognize an instruction for tagging the “tag 1” to the video data  421  based on a command of the program  321 . The control unit  31  controls the communication module  34  to transmit the instruction for tagging the “tag 1” to the video data  421  to the server  4  via the communication network  5 . In the meantime, the control unit  31  appends to the instruction the tag information generation time  424  at which it is informed that the “Register” button  66  has been pushed, and then transmits it thereto. The tag information generation time  424  may be a time of the absolute time that is associated with time data which are counted by, for example, a timekeeping means (not shown) integrated into the control unit  31  of the second terminal device  3 . The tag information acquisition module  412  of the server  4  acquires tag information  423  with the tag information generation time  424  from the second terminal device  3 , wherein the tag information  423  contains or is to be transmitted along with the tag information generation time  424 . 
     If two or more pieces of tag information  423  are simultaneously tagged to the video data  421 ; for example, “tag 1” and “tag 2” are simultaneously tagged to the video data  421  that are transmitted from the first terminal device  2 , once the control unit  31  is informed of a fact that the “tag 2” button  62  is pushed with the input means  33  after the tag information generation module  311  has recognized that the “tag 1” button has been selected, the control unit  31  makes the tag information generation module  321  recognize that the “tag 2” button  62  has been selected based on the instruction of the program  321 . If the control unit  31  is informed of a fact that the “Register” button  66  is pushed with the input means  33  at the time with both “tag 1” and “tag 2” buttons  61 ,  62  remaining selected, then the control unit  31  makes the tag information generation module  311  recognize an instruction for tagging the “tag 1” and “tag 2” to the video data  421  based on an instruction by the program  321 . The control unit  31  controls the communication module  34  to transmit the instruction for tagging the “tag 1” and “tag 2” to the video data  421  to the server  4  via the communication network  5 . In the meantime, the control unit  31  appends to the instruction the tag information generation time  424  at which it is informed that the “register button” is pushed, and then transmits it thereto. The tag information generation time  424  may be a time of the absolute time that is associated with time data which are counted by, for example, a timekeeping means (not shown) integrated in the control unit  31  of the second terminal device  3 . The tag information acquisition module  412  of the server  4  acquires tag information  423  with the tag information generation time  424  from the second terminal device  3  such that the tag information  423  contains or is to be transmitted along with the tag information generation time  424 . 
     Alternatively, in order to simplify an input for sending an instruction for tagging the video data  421 , the instruction for tagging the video data  421  may be sent, without ever pushing the “Register” button  66 , at a time when a tag button such as the “tag 1” button  61  is pushed. That is, if the input means  33  communicate a fact that the “tag 1” button  61 , for example, is pushed to the control unit  31 , then the control unit  31  makes the tag information generation module  311  to recognize an instruction for tagging “tag 1” to the video data  421  based on an instruction of the program  321 . The control unit  31  controls the communication module  34  to transmit the instruction for tagging “tag 1” to the video data  421  to the server  4  via the communication network  5 . In the meantime, the control unit  31  appends to the instruction with the tag information generation time  424  at which it is informed that the “tag 1” button  61  is pushed, and transmits it thereto. The tag information generation time  424  may be a time of the absolute time that is associated with time data which are counted by, for example, a timekeeping means (not shown) integrated into the control unit  31  of the second terminal device  3 . The tag information acquisition module  412  of the server  4  acquires tag information  423  with the tag information generation time  424  from the second terminal device  3 , wherein the tag information  423  contains or is to be transmitted along with the tag information generation time  424 . 
     In the second terminal device  3 , if the input means  33  communicate a fact that a text is entered into the “Comment” field  65  to the control unit  31 , then the control unit  31  makes the tag information generation module  311  recognize that the text is entered into the “Comment” field  65  based on an instruction of the program  321 . If it is communicated to the control unit  31  that the “Register” button  66  is pushed using the input means  33  when a text is entered in the “Comment” field  65 , then the control unit  31  makes the tag information generation module  311  recognize an instruction for tagging the comment, entered in the “Comment” field  65 , to the video data  421  based on an instruction by the program  321 . The control unit  31  controls the communication module  34  to transmit the instruction for tagging the comment, entered in the “Comment” field  65 , to video data  421  to the server  4  via the communication network  5 . In the meantime, the control unit  31  appends to the instruction the tag information generation time  424  at which it is informed that the “Register” button  66  is pushed, and then transmits it thereto. The tag information generation time  424  may be a time of the absolute time that is associated with time data which are counted by a timekeeping means (not shown) integrated in the control unit  31  of the second terminal device  3 . The tag information acquisition module  412  of the server  4  acquires tag information  423  with the tag information generation time  424  from the second terminal device  3 , wherein the tag information  423  contains or is to be transmitted along with the tag information generation time  424 . 
     There is no particular limitation to the manner by which the tag information generation time  424  is acquired as long as there can be obtained the absolute time at which tag information  423  is registered. For example, the tag information generation time  424  may be acquired from time data which are counted by, for example, a timekeeping means (not shown) integrated in the control unit  41  of the server  4 . In this case, the tag information acquisition module  412  of the control unit  41  stores time data in the storage device  42 , wherein the time data are made by the timekeeping means in the server  4  at a time at which the tag information  423  is received from the second terminal device  3 , as a tag information generation time  424  at which the tag information  423  is registered by the second terminal device  3 . Further, the tag information generation time  424  may be acquired from time data which are counted by other timekeeping means (not shown). 
     After the tag information acquisition module  412  of the control unit  41  controls the communication module  43  to receive the tag information generation time  424  and the instruction for tagging comments and/or tags such as “tag 1” to the video data  421 , the image processing module  413  appends tag information  423 , containing comments and/or tags, to the video data  421  stored in the storage device  42 ; i.e., to a frame  71  in which the received tag information generation time  424  and the identification information  425  as being data for the actual recorded time (absolute time) appended as a recorded time to the frame  71  match up with each other. The video distribution module  414  controls the communication module  43  to allow the tagged video data  426  to be distributed via the communication network  5  to, for example, the second terminal device  3  and/or the third terminal device  30  (See.  FIG. 3 ), where tags such as “tag 1” and/or comments are appended to the tagged video data  426  at a timing when the recorded time and the tag information generation time  424  are suitably in synchronization with each other. In such a way, there may be appended the tag information  423 , containing tags and/or comments, to video data  421  stored in the storage device  42  at a timing when the tag information generation time  424  of the tag information  423 , containing the tag and/or the comment, is in synchronization with the identification information  425  having the recorded time which is estimated based on the video recording start time  422  of the video stored in the storage device  42 . The video distribution module  414 , distributing the tagged video data  426  with the tag information  423  being appended to the video data  421 , may be configured in such a way that the video recording start time  422 , obtained by the video data acquisition module  411  from, for example, the first terminal device  2 , is not contained in the tagged video data  426  that are to be distributed from the video distribution module  414 . 
     If a plurality of second terminal devices  3 ,  3 ′,  3 ″ are provided, “tag 1” to “tag 4” may vary in their contents from one second-terminal device  3 ,  3 ′,  3 ″ to another. For example, as shown above, in the case where the user A is a coach, the user B is a defense analyst, and the user C is an offence analyst, the respective tags may be set to have matters that are frequently used and needed for each person in charge. Although  FIGS. 2 and 3  illustrate examples in which four tags from “tag 1” to “tag 4” are provided, the number of tags is not limited thereto. 
     The video distribution module  414  of the server  4  may be configured to distribute the tagged video data  426  to the second terminal device  3  and/or the third terminal device  30  to play them on the display screen  81  when tag information  423  is tapped on the display screen  81  of the second terminal device  3  and/or the third terminal device  30  while the tagged video data  426  to which the tag information  423  is appended are being distributed to the second terminal device  3  and/or the third terminal device  30 , wherein the tagged video data  426  include a timing in synchronization with the tag information generation time  424  corresponding to the tag information  423 . Distribution and playback of the tagged video data  426  will be described hereafter. 
       FIG. 3  schematically illustrates a preferred embodiment of the display screen  81  when playing the tagged video data  426  that are tagged. A video distributing terminal device for playing the tagged video data  426  that are tagged may, for example, be the second terminal device  3  or third terminal device  30 , or other device that can install and execute an application or software. Arranged in the upper region of the display screen  81  is a screen  82  for displaying, for example, game scenes that are regarded as video recording subjects. As for the playback of the video footage, operation button groups  83  displayed on the display screen  81  enable operations such as playback, pause, fast forward, fast rewind, playback of the next scene, playback of the previous scene, and playback speed change. 
     There are displayed tags  84  and/or comments  85  below the display screen  81  along a vertical line of the timeline TL in a sequential order in respect of the appended time. The displayed region  86  indicates that the user A registered “tag 1” button  61  and “tag 2” button  62  at 19:15, and further that “comment”  65  is registered at the same time. If the displayed region  86  including the tag information  423  is tapped, then a video beginning at 19:15 of the recorded time will be played. For the purpose of improving convenience, the playback may begin at a given time (e.g., 5 seconds) before 19:15 at which the tagging is made, or begin at a time few frames before 19:15 at which the tagging is made. A displayed region  87  indicates that the user B has been registered “tag 1” button  61 ′, “tag 3” button  63 ′ and “tag 2” button  62 ′ at 20:10, and further that “comment”  65 ′ has been registered at the same time. A displayed region  88  indicates that the user C has been registered “tag 4” button  64 ″ at 20:20, and further that “comment”  65 ″ has been registered at the same time. Further, when the displayed region  88  or the displayed region  87  having the tag information  423  is tapped, a video image of the corresponding time will be played in a way similar to the case when tapping the displayed region  86 . 
     There will be described an operation of the case where the second terminal device  3  is used as a display device for playing the tagged video data  426 . The third terminal device  30  has a configuration similar to the second terminal device  3 , and works in a way similar to the case where the second terminal device  3  is used even when the third terminal device  30  is used as a display device for playing a tagged video that has been tagged. As for the second terminal device  3 , if the control unit  31  is informed of a fact that the displayed region  86 , for example, is tapped with the input means  33 , then the control unit  31  controls the communication module  34 , based on an instruction of the program  321 , to transmit an instruction for playing the tagged video data  426  associated with the corresponding time on the displayed region  86  to the server  4  via the communication network  5 . The control unit  41  of the server  4  controls the communication module  43  to receive an instruction to play the tagged video data  426  that starts from the time at which the tag is appended. The video distribution module  414  acquires data about the instructed playback time from the tagged video data  426  stored in the storage device  42 . The control unit  41  of the server  4  controls the communication module  43  to distribute the tagged video data  426  that are to be played from the instructed playback time to the second terminal device  3  via the communication network  5 . The control unit  31  of the second terminal device  3  controls the communication module  34  to receive the tagged video data  426  that have been distributed. The control unit  31  controls, based on the instruction of the program  321 , the display module  35  to display the tagged video data  426  to be played from the instructed playback time on the display screen  60 . 
     Although not particularly limited thereto, the playback time for playing the tagged video data  426  from a desired tagged time may be restricted to, for example, a given period of time. For example, the playback time may be set for a particular period of time (e.g., 5 seconds), or there may be played video footage for a while until a tag next to the tag already having been played appears. Further, different playback times may be set depending on the contents of the tags (for example “tag 1” to “tag 4”) so that the periods of playback times are appropriately set for the scenes corresponding to the contents of the tags. It may be configured that the playback time is set by, for example, the video distribution module  414  of the server  4 . 
     The tags  84  and/or comments  85  may be displayed in a temporal order as shown in  FIG. 3 , or may be sorted out in accordance with the contents of the tags  84  appended thereto, or may be sorted out and rearranged in accordance with users by which they are appended thereto. 
     Applications or software for playing the tagged video data  426  and being activated based on the program  321  stored in the storage device  32  of the second terminal device  3  may be applications or software which are identical to the applications or software for tagging the video data  421 , or may be other independent applications or software. 
     There will be described a scheme of the video tagging method that is executed by the server  4  according to the present embodiment with reference to a flowchart in  FIG. 4  showing a preferred embodiment of the video tagging method according to the present invention. 
     In the first step S 1 , the control unit  41  of the server  4  controls the communication module  43  to establish a communication with the first terminal device  2 , and then in the next step S 2 , the video data  421 , having being made by recording actual game scenes using the first terminal device  2 , are obtained from the first terminal device  2  while acquiring time data for the video recording start time  422  of this video data  421 . In step S 3 , the control unit  41  memorizes and stores both the obtained video data  421  and time data of the video recording start time  422  in the storage device  42 . 
     Meanwhile, in step S 11 , the control unit  41  controls the communication module  43  to establish communications with a plurality of the second terminal devices  3 ,  3 ′,  3 ″, and then in the next step S 12 , determines whether or not there are transmitted data on the tag information  423  as mentioned and additionally, if the tag information generation time  424  is to be obtained from the second terminal device  3 ,  3 ′,  3 ″, data on the tag information generation time  424  from any of the second terminal devices  3 ,  3 ′,  3 ″. If there are transmitted the tag information  423 , and additionally, if required, time data on the tag information generation time  424 , then the control unit  41  moves to step S 13  to obtain them, and then in the next step S 14 , records and stores both the obtained tag information  423  and the time data on the tag information generation time  424  in the storage device  42 . The series of steps S 11  to S 14  is repeated until the distribution of the video data  421 , transmitted from the first terminal device  2 , is over such that a variety of tag information  423 , obtained from all of the second terminal devices  3 ,  3 ′,  3 ″, and the data on the tag information generation time  424  are accumulated in the storage device  42  over time. 
     After the obtained video data  421  and the time data on the video recording start time  422  are both recorded and stored in the storage device  42  in step S 3  as mentioned before, and the tag information  423  and the time data on the tag information generation time  424  are stored in the storage device  42  in step S 14 , the control unit  41  allows the tagged video data  426  to be distributed by the video distribution module  414  even while the video data are being acquired from the first terminal device  2  via upload. 
     Specifically, in step S 21 , the image processing module  413  integrated in the control unit  41  generates tagged video data  426  in which tag information  423  associated with its tag information generation time  424  is appended to a particular frame in the video data  421  at a timing synchronized with the tag information generation time  424 , based on time data on the video recording start time  422  that is read out from the storage device  42 , and a lapse of time from which the recording of the video data  421  is started, and then stores them in step S 22  in the storage device  42 . In step S 31  thereafter, the video distribution module  414  integrated in the control unit  41  controls the communication module  43  to establish communication with, for example, a third terminal device  30  that has received a request for distributing the tagged video data  426 , and then in step S 32 , the tagged video data  426  read out from the third storage device  42  are distributed to the third terminal device  30  via the communication network  5 . 
     In this way, while the tagged video data  426  are being distributed to the third terminal device  30 , the video distribution module  414  determines in step S 33  whether or not the tag information  423  on the display screen  81  of the third terminal device  30  is tapped based on the presence or absence of the playback instruction having been transmitted from the third terminal device  30 . Here, if a piece of particular tag information  423  is tapped on the display screen  81  of the third terminal device  30 , and a playback instruction is transmitted from the third terminal device  30 , then in step S 34 , the video distribution module  414  distributes the tagged video data  426  that starts, for example, from the time at which the tag is appended to the third terminal device  30 , based on the tag information generation time  424  corresponding to the tag information  423 , to play and display them on the display module  35 . 
     In the above-mentioned series of steps of the server  4 , the control unit  41  controls the communication module  43  not to transmit video data  421 , obtained from the first terminal device  2 , to second terminal device  3  during a period for which the second terminal device  3  is displaying a screen for producing the tag information  423  in step S 13 . Accordingly, the video data  421 , obtained from the first terminal device  2 , are prevented from being displayed on the display module  35  of the second terminal device  3 . Further, tagged video data  426  to be distributed to the third terminal device  30  in step S 32  are prevented from containing time data of the video recording start time  422  which are obtained in step S 2 . 
     There will be described examples to which the video tagging system  1 , including the video tagging device  4 , and the video tagging method according to the present embodiment can be applied. In the examples to be described below, specific functions of each component in the first terminal device  2 , the second terminal device  3 , the third terminal device  30  and the server  4  are as described in the above-described embodiments. 
     Example 1 
     &lt;Soccer&gt; 
     A soccer match is typically made up of first and second halves of 45 minutes each, and the duration of the match lasts very long. Further, there occurs so many events to which tags and/or comments are desired to be appended during the match. For this reason, according to a conventional method of making a tag by oneself while playing a recorded video, it is normally after the day following the match when the tagged video becomes available for a manager, coaches or analysts to be watched. 
     According to this example, a video shooter uses a first terminal device  2  to shoot, for example, a video of a match while the recorded video data  421  is transmitted to a server  4 . When sending the video data  421 , a video recording start time  422  at which the recording is started is transmitted from the first terminal device  2  to the server  4  upon, for example, the start of the recording for transmitting the video data. It will be appreciated that the manner of acquiring the video recording start time  422  is not limited to this. Meanwhile, users such as coaches or analysts responsible for inputting comments and/or tags using the terminal devices  3  input comments and/or tags while seeing an actual game scene that is taking place. The input tags and/or comments are dynamically tagged in real time to live footage of the recorded match by the video tagging system  1  having the video tagging device  4  or according to the video tagging method as explained in the embodiment. Accordingly, as the tagged video data  426  are made in real time, a manager, coaches, and analysts are allowed to provide feedback to players during a match or halftime while playing back footage of a scene with the desired tag from the tagged video data  426  that have been tagged. Further, as the tagged video data  426  are provided with tags and/or comments about what the coaches or analysts, for example, felt or noticed at the scenes they actually saw, appropriate feedbacks or analysis can be provided to the players. 
     For example, in the case of a soccer team, there may be allocated a plurality of coaches who are individually responsible for respective positions such as defenses, offences and a goalkeeper. Further, there may be a coach or trainer responsible for physical strength. 
     Analysts are often allocated into their respective positions of defense and offence. In this example, since such plurality of coaches, trainers and analysts are each able to append tag information  423  having comments and/or tags to the video data  421 , a more specialized coaching or analysis specific to each responsibility can be made. 
     In this example, examples of the contents for “tag 1” to “tag 4” according to the present embodiment include contents of events such as “Goal”, “Shoot”, “Pass”, “Clear”, “Saving”, “Tackle” and “Physical”, or contents indicating evaluation such as “Good” or “Bad”. For example, if a player fires in a shot, and it is determined that the shot is evaluated as being good, then a user such as a coach pushes “Shoot” and “Good” buttons in a row on a display screen  60  of the second terminal device  3  to thereby tag the tag information  423  of “Shoot” and “Good” to the live footage in association with a time at which the user such as coach input the tag after watching an actual scene. On a display screen  81  for playing tagged video data  426  is displayed the tag information  423  of “Shoot” and “Good” in association with the time at which the user such as coach inputs the tag after watching an actual scene, and if the corresponding display area is tapped, then the tagged video data  426  are played, based on the tag information generation time  424  associated with the tag information  423 , from the time at which the tag information  423  is input. It will be appreciated that one may input only tags on the content of the event or only tags on the content about evaluation. 
     Example 2 
     &lt;Baseball&gt; 
     In a baseball match, tagging to video data has conventionally been made only after completion of one inning, for example, at the earliest while play backing the video data having been recorded for that one inning which is manually delimited by a user. Further, the duration of the match lasts very long as is the case in example 1 for soccer, and there occurs so many events to which tags and/or comments are desired to be appended during the match. For this reason, according to a conventional method of making tags by oneself while playing a recorded video, it takes time until the tagged video becomes available for a manager, coaches or analysts to be watched. 
     According to this example, a video shooter uses a first terminal device  2  to shoot, for example, a scene of a match while the recorded video data  421  is transmitted to a server  4 . When sending video data  421 , a video recording start time  422  at which the recording is started is transmitted from the first terminal device  2  to the server  4  upon, for example, the start of the recording for transmitting the video data. It will be appreciated that the manner of acquiring the video recording start time  422  is not limited to this. Meanwhile, users such as coaches or analysts responsible for inputting comments and/or tags using the terminal devices  3  input comments and/or tags while seeing an actual game scene that is taking place. The input tags and/or comments are dynamically tagged in real time to live footage of the recorded match by the video tagging system  1  having the video tagging device  4  or according to the video tagging method as explained in the embodiment. Accordingly, as the tagged video data  426  are made in real time, a manager, coaches, and analysts are allowed to provide feedback to players even during a match or halfway through an inning that is being recorded while playing back footage of a scene with the desired tag from the tagged video data  426  that have been tagged. Further, as the tagged video data  426  are provided with tags and/or comments about what the coaches or analysts, for example, felt or noticed at the scenes they actually saw, appropriate feedbacks or analysis can be provided to the players. 
     For example, in the case of a baseball team, there may be allocated a plurality of coaches such as hitting coaches, pitching coaches, infield coaches, outfield coaches, base coaches, battery coaches and training coaches. Analysts are often allocated into their respective positions such as hitting, pitching and fielding. In this example, since such plurality of coaches and analysts are each able to append tag information  423  having comments and/or tags to the video data  421 , a more specialized coaching or analysis specific to each responsibility can be made. 
     In this example, examples of the contents for “tag 1” to “tag 4” according to the present embodiment include contents about hitting related events such as “Hit” and “Homerun”, contents about pitching related events such as “Fastball”, “Curve”, “High and Inside” and “Low and Outside”, and contents indicating evaluation such as “Strike”, “Ball”, “Good” and “Bad”. For example, if a pitcher throws a pitch whose pitch type is “Fastball” and the course is “High and Inside”, and the result is “strike”, then a user such as a coach pushes “Fastball”, “High and Inside” and “Strike” buttons in a row on a display screen  60  of the second terminal device  3  to thereby tag the tags of “Fastball”, “High and Inside” and “Strike” to the live footage in association with a time at which the user such as coach inputs the tag after watching an actual scene. On a display screen  81  for playing tagged video data  426  is displayed the tags of “Fastball”, “High and Inside” and “Strike” in association with the time at which the user such as coach inputs the tags after watching an actual scene, and if the corresponding display area is tapped, then the tagged video data  426  are played, based on the tag information generation time  424  associated with the tag information  423 , from the time at which tag information  423  is input. It will be appreciated that one may input only tags on the content of the event or only tags on the content about evaluation. 
     In examples 1 and 2, tags and/or comments may be appended not only to an event of the team to which a user belongs but also to an event of the rival team. 
     Example 3 
     &lt;Track and Field (Hurdling)&gt; 
     The video tagging system  1 , including the video tagging device  4 , and the video tagging method according to the present embodiment may be applied to the training or analysis not only of team ball games as exemplified in Examples 1 and 2 but also of individual sports such as track-and-field sports such as hurdling. 
     According to this example, a video shooter uses a first terminal device  2  to shoot, for example, a scene of an athlete jumping a hurdle while the recorded video data  421  is transmitted to a server  4 . When sending the video data  421 , a video recording start time  422  at which the recording is started is transmitted from the first terminal device  2  to the server  4  upon, for example, the start of the recording for transmitting the video data. It will be appreciated that the manner of acquiring the video recording start time  422  is not limited to this. Meanwhile, users such as coaches responsible for inputting comments and/or tags using the terminal devices  3  input comments and/or tags while seeing an actual scene of jumping a hurdle. The input tags and/or comments are dynamically tagged in real time to live footage of the recorded scene of jumping the hurdle by the video tagging system  1  having the video tagging device  4  or according to the video tagging method as explained in the embodiment. Accordingly, as the tagged video data  426  are made in real time, coaches are allowed to provide feedback to an athlete right after the end of a run while playing back a footage of a scene with the desired tag from the tagged video data  426  that have been tagged. 
     In this example, examples of the contents for “tag 1” to “tag 4” according to the present embodiment include contents of events such as “Hurdle”, “Interval” and “Start” or contents indicating evaluation such as “Good” or “Bad”. For example, the term “interval” as used herein refers to a run between two hurdles. For example, if an athlete accidentally knocks over a hurdle, then a user such as a coach pushes “Hurdle” and “Bad” buttons in a row on a display screen  60  of the second terminal device  3  to thereby tag the tags of “Hurdle” and “Bad” to the live footage in association with a time at which the user such as coach input the tag after watching an actual scene. On a display screen  81  for playing tagged video data  426  is displayed the tags of “Hurdle” and “Bad” in association with the time at which the user such as coach inputs the tags after watching an actual scene, and if the corresponding display area is tapped, then the tagged video data  426  are played from the time at which the tag information  423  is input. Accordingly, coaches are allowed to provide feedback to the athlete about, for example, an improvement of his/her forms right after the end of a run while playing back tagged video data  426  corresponding to the scene of accidentally knocking over a hurdle. It will be appreciated that one may input only tags on the content of the event or only tags on the content about evaluation. 
     As indicated above, the video tagging device  4  in the present embodiment comprises: 
     a video data acquisition module  411  to acquire video data  421  recorded by a first terminal device  2  from the first terminal device  2  and to acquire a video recording start time  422  at which recording of the video data  421  is started, and then have the video data  421  and the video recording start time  422  stored in a storage device  42 ; 
     a tag information acquisition module  412  to acquire tag information  423  having tags and/or comments from a second terminal device  3  when the tag information  423  is generated in the second terminal device  3 , and to acquire a tag information generation time  424  at which the tag information  423  is generated; and 
     an image processing module  413  to append the tag information  423  to the video data  421  at a timing synchronized with the tag information generation time  424  based on the video recording start time  422  stored in the storage device  42  and a lapse of time from which the video recording of the video data  421  is started. 
     The video tagging method in the present embodiment comprises: a first step of acquiring video data  421  recorded by a first terminal device  2  from the first terminal device  2  and acquiring a video recording start time  422  at which recording of the video data  421  is started; a second step of storing the video data  421  and the video recording start time  422  in a storage device  42 ; a third step of acquiring tag information  423  having tags and/or comments from a second terminal device  3  when the tag information  423  having tags and/or comments is generated in the second terminal device  3 , and acquiring a tag information generation time  424  at which the tag information  423  is generated; and a fourth step of appending the tag information  423  to the video data  421  in a timing synchronized with the tag information generation time  424  based on the video recording start time  422  stored in the storage device  42  and a lapse of time from which the recording of the video data  421  is started. 
     In these cases, video data  421  are acquired from the first terminal device  2 , and the video recording start time, as being an absolute time, is also acquired to store them in the storage device  42  to correct the deviation in the playback time of the video data  421  with reference to the actual time based on this video recording start time  422  and a lapse of time from which the video recording of the video data  421  is started in order to append the tag information  423  to the video data  421  at a timing appropriately synchronized with the tag information generation time  424  acquired by the tag information acquisition module  412  to thereby make the tagged video data  426 . The users are thus capable of tagging tag information  423 , containing tags and/or comments having been input in second terminal device  3 , in correct time synchronization with the video data of the live footage that is being streamed in real time (the footage is streamed after a delay of a few tens of seconds in effect) while seeing an actual scene that is the video recording subject of the video instead of watching video footage. 
     As for the tagging device  4  according to the present embodiment, the tag information acquisition module  412  may be configured to obtain tag information  423  from a plurality of the second terminal devices  3 ,  3 ′,  3 ″. 
     As for the video tagging method according to the present embodiment, the tag information  423  is obtainable in the third step from a plurality of the second terminal devices  3 ,  3 ′,  3 ″. 
     In these cases, a plurality of users are allowed to tag the tag information  423 , produced in the respective second terminal devices  3 , in correct time synchronization with the video data  421  of the live footage to be streamed in real time while seeing an actual scene to thereby readily share the tag information  423 . 
     As for the video tagging device  4  according to the present embodiment, the video tagging device may be configured not to transmit the video data  421 , acquired from the first terminal device  2 , to the second terminal device  3  during a period for which the second terminal device  3  is displaying a screen for producing the tag information  423 . 
     As for the video tagging method according to the present embodiment, the video data  421  acquired from the first terminal device  2  may be not transmitted to the second terminal device  3  during a period for which the second terminal device  3  is displaying a screen for producing the tag information  423  in the third step. 
     In these cases, at least in the case where a user utilizes the second terminal devices  3  to generate the tag information  423 , if it is configured that the video data  421  are not transmitted to that second terminal device  3 , the user is prevented from tagging video data  421  in a wrong timing while watching not an actual game scene but live footage on the second terminal devices  3 . 
     The video tagging device  4  according to the present embodiment may further comprise a video distribution module  414  to distribute a tagged video data  426  with the tag information  423  being appended to the video data  421 , wherein the video tagging device is configured not to contain the video recording start time  422  acquired by the video data acquisition module  411  in the tagged video data  426  that are to be distributed from the video distribution module  414 . 
     The video tagging method according to the present embodiment may further comprise a fifth step of distributing tagged video data  426  with the tag information  423  being appended to the video data  421 , wherein the video recording start time  422  acquired in the first step is not contained in the tagged video data  426  to be distributed in the fifth step. 
     In these cases, the tagged video data  426  may be directly distributed from the video distribution module  414  without embedding information on the video recording start time  422 —which may be superfluous—into the tagged video data  426 . 
     The video tagging device  4  according to the present embodiment may further comprise a video distribution module  414  to distribute tagged video data  426  to a third terminal device  30  upon tapping the tag information  423  on the display screen  81  of the third terminal device  30  during a period for which the tagged video data  426  of which the tag information  423  is appended to the video data  421  are being distributed to the third terminal device  30 , wherein the tagged video data  426  to be distributed to the third terminal device  30  contains a timing synchronized with the tag information generation time  424  corresponding to the tag information  423 . 
     The video tagging method according to the present embodiment may further comprise a sixth step of distributing tagged video data  426  to a third terminal device  30  upon tapping the tag information  423  on the display screen  81  of the third terminal device  30  during a period for which the tagged video data  426  of which the tag information  423  is appended to the video data  421  are being distributed to the third terminal device  30 , wherein the tagged video data  426  to be distributed to the third terminal device  30  contains a timing synchronized with the tag information generation time  424  corresponding to the tag information  423 . 
     In these cases, when a tag information  423  is tapped on the display screen  81  during a period for which the tagged video data  426  are being viewed in the third terminal device  30 , the tagged video data  426  associated with that tag information  423  are distributed from the video distribution module  414  to the third terminal device  30 , and then the footage is played in the third terminal device  30 . Accordingly, one may retrieve footage of scene to review the desired scene by a simple tapping operation even during a match or halftime, or even halfway through an inning. 
     Although the present invention has been described above based on the embodiments, the present invention can be modified to be embodied in various ways. For example, the examples described in the above examples are merely examples, and the present invention can be applied to other various applications. 
     For example, the video tagging system having the inventive video tagging device and the video tagging method may be utilized for the training or analysis not only of soccer, baseball, and track-and-fields (hurdling) as explained above but also of other ball games such as rugby, American football, basketball and volleyball as well as figure skating, dancing and gymnastics. Further, it can be applied not only to sports but also to dramas, musical performances, lectures, speech contests and other various presentations. 
     The video tagging system having the inventive video tagging device and the video tagging method may readily be implemented because they can be embodied using a portable information terminal device such as a smartphone or a tablet terminal. Further, the way it is used is simple. For these reasons, not only a professional user but also an amateur user can proactively take advantage of it. For example, parents often video-record their kid&#39;s play or performance to utilize it for the purpose of practice. If tagging can be made in real time while recording the video, it reduces the parent&#39;s burden of finding the desired scene by repeating, for example, playback and/or rewind after the recording. Further, it also greatly helps children to enhance their ability. It will be appreciated that the video tagging system having the inventive video tagging device and the video tagging method may be utilized for the purpose of matches or real performance, or for the purpose of practices before real performance. 
     LIST OF REFERENCE NUMERALS 
     
         
           1  video tagging system 
           2  first terminal device 
           3  second terminal device 
           311  tag information generation module 
         third terminal device 
           4  video tagging device (server) 
           41  control unit 
           411  video data acquisition module 
           412  tag information acquisition module 
           413  image processing module 
           414  video distribution module 
           42  storage device 
           421  video data 
           422  video recording start time 
           423  tag information 
           424  tag information generation time 
           425  identification information 
           426  tagged video data 
           427  program 
           43  communication module 
           5  communication network 
           71  frame 
           84  tags 
           85  comments