JP2009118168A - Program recording / reproducing apparatus and program recording / reproducing method - Google Patents

Abstract

When recording and reproducing a digital broadcast program, it is possible to perform both reproduction by an optimal index using subtitles and reproduction by a keyword voluntarily input by a user, and a scene including a keyword in the subtitles can be recorded by the user. Is displayed in an easy-to-understand manner.
In a program recording / playback apparatus, digital broadcast data including caption information is analyzed, and caption text data is output. Furthermore, the caption text data is analyzed, and index data is generated based on the feature extraction rule and the validity of the appearing keyword. When playing a recorded program, the position of the index keyword selected by the user on the program and the position of the keyword input by the user are displayed on the program playback screen in an easy-to-understand manner. It can be played from the position of the program.
[Selection] Figure 1

Description

  The present invention relates to a program recording / playback apparatus and a program recording / playback method, and in particular, when receiving a digital broadcast program for recording / playback, an optimal index included in the subtitle is included in each program by an index using the subtitle. The present invention relates to a program recording / reproducing apparatus and a program recording / reproducing method suitable for reproducing a user's desired scene on the basis of a keyword entered by the user or a keyword input as a voluntary search.

  In recent broadcasting, digital broadcasting that broadcasts video as digital data has become mainstream. This digitization is said to enable new broadcasting services such as high image quality (high-definition broadcasting), multi-channel broadcasting, data broadcasting, broadcasting for mobile reception (cell phones, etc.).

  As a storage medium for digital TV broadcasting, it is possible to reserve a large number of programs such as optical disks such as DVD (Digital Versatile Disk) and hard disk drives (HDDs), and to edit and delete them quickly and easily. Digital storage media that can be used are used. As long as the capacity of the storage medium allows, the user can easily record the program of interest and browse the program at his / her favorite time without being restricted by the broadcast time. Under such circumstances, since the viewable time is limited, the user wants to view the desired scene with the head.

  Patent Document 1 discloses a means for extracting a requested scene that seems to meet a user's request by taking out subtitle information multiplexed and stored together with video and performing a character string search or the like.

  Further, Patent Document 2 provides a video recording apparatus that stores a keyword and its generation time as index information during recording and records it on a recording medium together with a video signal when the scene level is equal to or higher than a reference value. Is disclosed.

JP 2005-115607 A JP 2006-157108 A

  In the apparatus disclosed in Patent Document 1, caption information is accumulated, a requested scene that seems to meet the user's request is extracted as a candidate, image analysis and audio analysis are performed on the candidate scene, and as a result, the user's request A scene that is determined to satisfy is extracted. By using subtitles as described above, it is possible to save time and labor for manually creating information related to content as compared with the prior art.

  However, in Patent Document 1, when subtitle information that has been multiplexed and stored is extracted and searched, it takes time to search for packets including subtitles, and therefore it may take time to search for a scene. Also, once the subtitle information is decoded and saved, it may correspond to content duplication, so content with copy restrictions may cause violations of standards or copyright issues. There is a fear.

  In Patent Document 2, leveling is performed based on the occurrence frequency of keywords and the like, and keywords of a certain level or more are recorded as index information on a recording medium.

  However, since there is only an index for the keyword that is determined to be optimally determined by the system, there is no means for the user to select and search for the keyword independently, and the degree of freedom is low. On the other hand, there is no means for informing the user that the index has been correctly generated for the content, and there is no means for informing the user where the scene corresponding to the keyword is located in the entire program. There was a problem of being bad.

  The present invention has been made to solve the above-described problems. The purpose of the present invention is to reproduce an optimal index using subtitles and a keyword that a user inputs independently when recording and reproducing a digital broadcast program. It is to enable both of the reproduction by.

  Another object is to provide a user interface that displays a scene including an index in a caption in an easy-to-understand manner for the user.

  Another object is to enable a keyword search at a high speed with respect to a keyword that is independently input by a user.

  In order to solve the above problems, the program recording apparatus of the present invention separates broadcast data received from a digital broadcast and extracts a caption ES. Then, the caption ES is analyzed, and caption text data including the caption text, the control code, and the display time is output.

  Furthermore, the caption text data is analyzed, and index data is generated based on the feature extraction rule and the validity of the appearing keyword.

  When replaying a recorded program, the position of the index keyword program selected by the user is displayed on the program replay screen in an easy-to-understand manner based on the index data so that it can be reproduced from the position of the keyword program. .

  In addition, the program playback screen allows the user to input a keyword, and based on the index data, the keyword program position input by the user is displayed in a visually easy-to-understand manner so that the keyword program position can be played back. To do.

  Further, when a plurality of categories corresponding to one program are provided, the keyword to be searched is changed.

  According to the present invention, when a digital broadcast program is recorded and reproduced, both reproduction using an optimal index using subtitles and reproduction using a keyword voluntarily input by a user are possible.

  Further, according to the present invention, it is possible to provide a user interface that displays a scene including a keyword in a caption in an easy-to-understand manner for the user.

  Furthermore, according to the present invention, it is possible to perform a keyword search at high speed with respect to a keyword that is independently input by a user.

  Embodiments according to the present invention will be described below with reference to FIGS.

Embodiment 1
A first embodiment according to the present invention will be described below with reference to FIGS.

First, the configuration of the program recording / playback apparatus according to the first embodiment of the present invention will be described with reference to FIG.
FIG. 1 is a block diagram showing the configuration of a program recording / playback apparatus according to the first embodiment of the present invention.

  As shown in FIG. 1, the program recording / playback apparatus of this embodiment includes a recording / playback unit 101, a display device 102, an input device 103, a tuner 104, an antenna 105, a RAM 106, and an external storage device 107. I have.

  The recording / playback unit 101 is a part that records and plays back a broadcast program in the external storage device 107. The recording / playback unit 101 is divided into processing blocks for performing each process when recording or playing back a program.

  The display device 102 is a part that displays video and audio, and displays video and outputs audio when the recorded content is played back. The display device 102 is configured by, for example, a television or personal computer display or a liquid crystal panel.

  The input device 103 is a device in which a user performs an operation on the program recording / playback device and inputs control information and data related to an operation input by the user. For example, a remote controller, a keyboard, a mouse, a pen input device, etc. This is realized by a pointing device or a liquid crystal touch panel.

  The RAM 106 is a volatile memory, and is a storage device that stores temporary data and programs processed by the recording / playback unit 101.

  The tuner 104 is a part that selects and acquires broadcast program data from radio waves received from a broadcast station.

  The antenna 105 is a part that receives broadcast radio waves according to the band of digital broadcasting. For example, an antenna for digital terrestrial broadcasting receives UHF band radio waves.

  The external storage device 107 is a device having a large storage capacity, and is, for example, an optical disk such as a DVD or an HDD.

  Next, each processing block of the recording / playback unit 101 will be described. Each processing block may be, for example, software that operates on a general-purpose processor such as a CPU, or each block may be processed by dedicated hardware. Also, a device in which software and hardware are mixed may be used.

  As shown in FIG. 1, the recording / playback unit 101 includes a system control unit 110, a signal separation unit 111, a caption analysis unit 112, a program recording unit 113, an index generation unit 114, and a keyword list acquisition unit 115. , A playback position list acquisition unit 116, a program playback unit 117, and a video output unit 118.

  The system control unit 110 receives a user operation request via the input device 103 and controls the operation of each block of the recording / playback unit 101. In addition, it controls the operation of each block of the recording / playback unit 101 in recording and playing back programs.

  The signal separation unit 111 has a function of separating received broadcast data for each type of video data, audio data, caption text data, program information data, and the like and passing the separated broadcast data to other processing blocks. When there is a data transmission request from another processing unit, the designated data is transmitted to the request source. Further, broadcast program data received from the tuner 104 and recorded program data 121 stored in the external storage device 107 can be input to the signal separation unit 111.

  The keyword list acquisition unit 115 analyzes index data 123 (described later) stored in the external storage device 107 according to an instruction from the system control unit 110, acquires a keyword list to be presented to the user during program playback, and outputs video To the unit 118.

  The reproduction position list acquisition unit 116 outputs a reproduction position list for the keyword designated by the user to the video output unit 118 in accordance with an instruction from the system control unit 110.

  The program playback unit 113 acquires 121 recorded program data stored in the external storage device 107 of the program instructed by the user in accordance with an instruction from the system control unit 110, and inputs it to the signal separation unit 111. Thereafter, the video ES (described later) and the audio ES (described later) are obtained from the signal separation unit 111 and decoded, and the video and audio data are output to the video output unit 118.

  When there is a program recording request via the system control unit 110, the program recording unit 113 requests a data stream from the signal separation unit 111 and stores it as recorded program data 121 in the external storage device 107. To do. The program recording unit 113 may store the entire data stream as the recorded program data 121 according to the user's specification, or may store only the video ES and the audio ES by selecting them to reduce the storage area.

  The video output unit 118 receives the outputs of the keyword list acquisition unit 115, the reproduction position list acquisition unit 116, and the program reproduction unit 117, configures a screen, and outputs video and audio to the display device 102.

  Upon receiving a caption analysis request from the system control unit 110, the caption analysis unit 112 acquires a caption ES (described later) and a time stamp from the signal separation unit 111. Then, the caption ES is analyzed and stored as caption sentence data 120 on the RAM 106.

  The index generation unit 114 outputs the index data 123 to the external storage device 107 using the caption sentence data 120 and the dictionary data 122.

  The caption text data 120 is data that the caption analysis unit 112 analyzes the caption ES and stores in the RAM 106 in a unique format. Details of the caption text data 120 will be described later.

  The external storage device 107 stores recorded program data 121, dictionary data 122, and index data 123.

  The dictionary data 122 is data in which a list of keywords to be output as an index is arranged. As will be described later, the index is a heading or index that can be specified by the user when playing a program. However, the dictionary data 122 may not be provided when the subtitle content is not analyzed, for example, only when a blank section of the subtitle sentence data 120 is detected. Further, it does not necessarily exist only in the external storage device 107, and may be acquired by means such as the Internet, broadcast waves, or flash memory. Or you may possess the structure which updates a dictionary from a user's operation history or EPG.

  The recorded program data 121 is program data including information such as video, audio, and captions.

  The index data 123 is data that holds information about keywords included in subtitles for each program. Details of the index data 123 will be described later.

Next, a data structure related to the program recording / playback method of the present embodiment will be described with reference to FIGS.
FIG. 2 is a diagram illustrating a data structure of a data stream in digital broadcasting.
FIG. 3 is a diagram showing the format of the caption text data 120.
FIG. 4 shows the data structure of the index data 123. As shown in FIG.

  In digital broadcasting, MPEG-2 TS (Transport Stream) is used as a transmission method. Video data, audio data, and all data used in data broadcasting are transmitted in a TS packet 201 shown in FIG.

  In particular, video data, audio data, and caption text data are encoded and compressed into ES (Elementary Stream), and become video ES 202, audio ES 203, and caption ES 204, respectively. These ESs are packetized in a PES (Packetized Elementary Stream) format to which a PES header 205 indicating display time information and the like is added. The PES header 205 includes a time stamp, and reproduction synchronization of each packet can be achieved by using this time stamp. As can be seen from FIG. 2, one PES packet may be created from the payloads of a plurality of TS packets.

  The signal separation unit 111 shown in FIG. 1 analyzes the data stream of FIG. 2 and separates it for each packet type.

  Next, caption text data 120 will be described with reference to FIG.

  The caption text data 120 is stored in a table format of a time stamp 301, a caption sentence 302, and a control code 303, as shown in FIG.

  The time stamp 301 is a caption display time included in the PES header 205, and is displayed as a relative time from the recording start time.

  The caption text 302 is text information included in the caption ES 204.

  The control code 303 is data for controlling subtitle display such as a character color, a drawing position, and erasing included in the subtitle ES 204.

  When the system control unit 110 makes a subtitle display request, the time stamp 301 is monitored. When the display time comes, the subtitle sentence 302 and the control code 303 are transmitted to the video output unit 118 and can be displayed as subtitles. .

  In addition, a fixed amount of caption text data 120 is accumulated according to the capacity of the RAM 106. The caption analysis unit 112 monitors the amount of data stored in the caption text data 120, and notifies the system control unit when it is determined that more than a predetermined amount of data has been stored in the RAM.

  Next, the index data 123 will be described with reference to FIG.

  The index data 123 is data generated for each program, and is information on keywords included in the caption, and is used when the program is played back using the index.

  The index data 123 has a hierarchical structure as shown in FIG. 4, and the highest layer includes a head index header (hereinafter referred to as “IDX header”) 601 and a plurality of subsequent layers. Index section (hereinafter referred to as “IDX section”) 602 that may be generated.

  The IDX header 601 includes data serving as index data attributes. Information including only one, for example, a recording start time and end time, and a unit of a PTS (Presentation Time Stamp) that is a time indicated by the index, Program information and the like are included, and the total number of IDX sections 602 is included. In addition to the program information acquired from the EPG, additional information at the time of recording such as image quality setting may be added.

  The IDX section 602 is created separately from other IDX sections depending on differences in keyword attributes and keyword usefulness determination algorithms. For example, when the program categories are different, different keyword attributes and keyword usefulness determination algorithms are used. Therefore, the IDX section is created corresponding to each program category. For example, since the keyword “baseball program” and the category “news program” have different keywords and keyword usefulness determination algorithms, different IDX sections are created.

  Each IDX section is divided into a plurality of segments having a hierarchical structure as shown in FIG. One section header 603 and a keyword segment 604 that may be included in a plurality are successively formed at the top.

  The section header 603 is a segment indicating the attribute of the IDX section. The section header 603 can be, for example, a section ID 605, a section size 606, and a PTS type 607.

  The section ID 605 is an ID number indicating a section attribute, and is unique for each IDX section included in the same index data. Since the program playback apparatus that handles index data checks the section ID and determines how to use the IDX section, each index data of a plurality of programs uses the same section ID when the same keyword usefulness determination algorithm is used. It is preferable to do this.

  A section size 606 indicates the overall size of the segment. The PTS type 607 is a code that distinguishes the expression method of the PTS included in the keyword segment 604. An example of a PTS expression method will be described later.

  The keyword segment 604 is a segment for storing a keyword and its appearance position. The keyword segment 604 has a hierarchical structure divided into a plurality of units. The keyword segment 604 includes one keyword attribute 608 at the top and a PTS unit 609 that may have a plurality of units.

  The keyword attribute 608 includes, for example, a keyword segment size 610 that is the size of the keyword segment, a keyword length 611, a keyword name 612, and a PTS unit number 613 that indicates the number of PTS units included in the keyword segment. .

  The PTS unit 609 indicates the position where the keyword appears or the position of the scene where the keyword appears. The storage method of the PTS unit 609 differs depending on the PTS type 607 included in the section header 603. For example, if type 1 is pointed in PTS 607, only the appearance time for the keyword is stored, and if type 2 is pointed, as the pair of the start and end times of the scene in which the keyword appears Shall be stored.

Next, processing of each part of the program recording / playback method according to the first embodiment of the present invention will be described with reference to FIGS.
FIG. 5 is a flowchart illustrating a process in which the index generation unit 114 generates index data.
FIG. 6 is a flowchart showing details of the index data output process.
FIG. 7 is a flowchart showing processing at the time of program recording.
FIG. 8 is a flowchart showing a process of presenting to a user whether or not index reproduction based on keywords included in subtitles is possible.
FIG. 9 is a diagram showing a program list screen in a case where the user is shown whether or not index reproduction by subtitles is possible.
FIG. 10 is a diagram illustrating an example of a user interface of a program playback screen that performs index playback using subtitles.

  First, the process in which the index generation unit 114 generates index data will be described with reference to FIG.

  The index generation unit 114 is instructed by the system control unit 110 to start processing for generating index data.

  The index generation unit 114 first acquires the dictionary data 122 from the external storage device 107 (step 401).

  Next, program information is acquired (step 402). The program information is an electronic program guide (EPG) for digital broadcasting, and is acquired from the signal separation unit 111 by analyzing the broadcast data and the recorded program data 121 shown in FIG.

  Next, the caption text data 120 shown in FIG. 3 is acquired as a time stamp 301, caption text 302, and control code 303 as one record (step 403).

  Next, one feature detection rule is acquired (step 404). The feature detection rule is a rule used to determine whether the input caption text data 120 is a specific pattern. For example, it is determined whether the dictionary keyword acquired in step 401 in FIG. 4 is included. To find a specific control code for emphasizing subtitles. In addition, since the keywords of the caption text data 120 are often repeated in context, the duplicate keywords after the second time are not assumed to be characteristic, and a specific keyword of the caption text data 120 appears more than a certain interval. If it exists after that, it can be determined that the feature detection rule matches.

  Although the feature detection rule is not shown in FIG. 1, the feature detection rule may be held internally as control data of the index generation unit 114, or may be stored in the external storage device 107 and taken out as necessary.

  Next, index data output processing is performed based on the caption text data and the feature detection rules acquired in steps 403 and 404, respectively (step 405).

  The index data output process will be described later in detail with reference to FIG.

  Next, after finishing the index data output process of step 405, it is determined whether there is an undetermined feature extraction rule (step 406).

  If there is another feature extraction rule, the process returns to step 404 to obtain another feature extraction rule and output index data.

  When all the feature extraction rules are applied, it is determined whether or not the caption text data 121 remains (step 407).

  If other subtitle sentence data 121 remains, the process returns to step 403 to acquire the next subtitle sentence data.

  After applying the processing of Steps 403 to 406 to all the caption text data 121, the index generation unit 114 ends the processing of generating index data.

  Next, the index data output process will be described in detail with reference to FIG.

  First, it is determined whether or not the caption text data 121 acquired in step 403 in FIG. 4 matches the feature detection rule (step 501).

  If it is determined that the feature detection rule is not met, the process ends.

  If it is determined that the feature detection rule is met, the usefulness of the keyword is determined based on a method for determining the usefulness of a certain keyword (step 502). In step 403, related words and similar words for the dictionary keyword may be searched simultaneously. For example, in a baseball program, if the dictionary keyword is “scoring scene”, it is simultaneously determined whether or not the keyword indicates that a score such as “timely hit” or “home run” has been entered.

  The determination of the usefulness of the keyword is a process of determining whether or not to output to the index data according to the type of the recorded program for the keyword acquired in the process of step 403. As a means for determination, the determination is made based on the context of surrounding subtitle sentences, the appearance frequency and interval of keywords, or the rule of control codes.

  For example, scoring scenes and fine play are examples of scenes that are generally selected and played by a user in a baseball program. Therefore, even if the subtitle sentence 301 includes a keyword related to the scoring scene, if it is a sentence such as "Today's second batter was a home run", the past batter's play is simply Therefore, it is considered that the scene is not linked to the scene that the user wants to see. Therefore, even if the keyword is included in the caption, it is determined that it is not included in the scoring scene. In addition, when the word “home run” is detected, it is determined that the word “home run” is useful when there is no similar word between certain intervals before and after the appearance. This is because the second and subsequent times are simply repeated explanations, so it is assumed that the information is not valid, and at the first appearance, it is assumed that there are many scoring scenes in which “home run” occurred in that scene. .

  Also, the method for determining the usefulness of keywords can be changed for each category of program. This is because even if a single program is regarded as a category different from, for example, a music program or a variety program, the effectiveness of the keyword is considered different. In addition, the effectiveness of a keyword may be determined by categorizing a high-level concept and a low-level concept, such as a category of “sports” and a category of “baseball”, for a live baseball program.

  When the determined keyword is an effective keyword (step 503), the index data 123 is output in the format according to FIG. 4 (step 504).

  At that time, the index data 123 is output so that one IDX section 602 is configured for one category. Therefore, when one program is classified into a plurality of categories, a plurality of IDX sections 602 are generated.

If there are many categories of the program and the amount of calculation for determining effective keywords and the index data 123 become large, the category for limiting the category may be applied to reduce the output category. For example, in the program information included in the EPG of digital broadcasting, a plurality of genre codes may be assigned to one program. Therefore, the effective keyword determination by an algorithm suitable for the genre obtained from these genre codes may be performed, and each ID code section 602 may be output for each genre code. Specific procedure for outputting index data Is as follows.

  First, the IDX section 602 to be output from the IDX section 602 included in the index data in FIG. 4 is determined according to the determination method used for the effective keyword determination method. If there is no suitable IDX section 602, a new IDX section 602 is created.

  Next, it is determined whether or not the keyword to be output is included in each keyword segment 604. If there is a keyword segment 604 having the same keyword name 612 as the output keyword, the playback position for the keyword is output to the PTS unit 609 of the keyword segment according to the PTS type. Also, if there is no keyword segment 604 having the same keyword name 612 as the output keyword, a new keyword segment 604 is added. After adding the playback position of the output keyword to the keyword segment 604, the keyword segment size 610 and the section size 606 are updated.

  The reproduction position added here changes the output method according to the IDX section. For example, the time stamp of caption text data may be output as it is. In the case of a live broadcast program such as a news program, the appearance time of a keyword may deviate from the appearance time of a broadcast subtitle. Therefore, the playback time corresponding to the output keyword may be a certain time before the time stamp of the caption text data if it is detected from the program information or the like whether the recorded program is a live broadcast. In addition, when it is necessary to detect a scene, such as when a section in which caption texts are continuous is detected, it may be stored in the PTS unit in the PTS type 2 format of FIG.

  After outputting to the index data 123, it is determined whether or not the caption text data has performed all the effective keyword determination methods supported by the recording / playback apparatus (step 505). If there is another effective keyword determination method to be applied, the process returns to 502 again, and another effective keyword determination method is applied. On the other hand, if all the effective keyword determination methods are applied, the process is terminated.

  Next, processing of the program recording / playback apparatus during program recording will be described with reference to FIG.

  When the user instructs to record a program, the recorded program data 121 is output and the index data 123 is generated in accordance with the processing shown in FIG.

  First, the system control unit 110 instructs a transition to a program recording state by a reserved recording of a program or a recording instruction of a user. When receiving the broadcast data, the signal separation unit 111 performs a separation process on the broadcast data in the format as shown in FIG. 2 based on a transfer request registered before analysis and recording (step 701), and the program recording unit 113. And the transfer processing of the desired data to the caption analysis unit 114 is performed. Then, the program recording unit records the recorded program data 121 in the external storage device 107 (step 702).

  On the other hand, the caption ES 204 is simultaneously input to the caption analysis unit 112, and the caption analysis unit 112 outputs the caption text data 122 (step 703). Here, the index generation unit 114 uses subtitle sentence data included in a certain section for evaluation in the keyword validity determination used in step 502 in FIG. 6. Therefore, a fixed amount of caption text data 122 is stored in the RAM 106. When the accumulation amount of the caption text data 122 becomes a certain amount or more (step 702), the caption analysis unit 112 notifies the system control unit 110. Upon receiving notification from the caption analysis unit 112, the system control unit 110 instructs the index generation unit to perform the index data generation process described with reference to FIG.

  If it is determined that a certain amount or more has not been accumulated, it is determined whether or not the program has ended (step 706). When the program ends, index data is generated using the caption text data 120 on the RAM 106. (Step 707), and the process ends. If the program has not ended, the broadcast data reception wait state is entered again (step 708).

  Next, processing for presenting the user with whether or not index reproduction using subtitles is possible will be described with reference to FIGS. 8 and 9.

  As shown in FIG. 9, when index playback using subtitles is possible for the user, the fact is displayed on the program list screen 800 displayed on the display device 102.

  Here, the index reproduction refers to reproduction using index data 123 created using subtitles.

The program list screen 800 displays program thumbnails 801 and program information 802 of a plurality of recorded programs. Here, it is assumed that, for example, a star mark is added as an index reproducible mark 803 to a program in which the recorded program apparatus generates the index data 123 and the index replay can be performed using the keywords included in the subtitles. This may be displayed with a message such as “index playback”, or may be displayed by changing the color of the program thumbnail 801, etc. Presenting to the user whether index playback using subtitles is possible For the processing to be performed, first, the number N of recorded programs stored in the external storage device 107 is acquired (step 901).

  Next, the index data 123 of the Nth program is acquired (step 902).

  Next, the keyword list acquisition unit 115 analyzes the index data 123 and determines the validity of the index data 123 according to the category of the target program.

  Hereinafter, the process for determining the validity of the index data 123 will be described in detail. Here, it is assumed that the program category is a category determined by information such as a program genre, a program title, a broadcast time zone, and a broadcast station. For example, in the case of a baseball program, a chapter including the appearance position of a keyword related to a scoring scene and a strikeout scene is designated to enable reproduction.

  First, it is determined whether the IDX section 602 corresponding to the category of the baseball program is included in the index data shown in FIG. If it is not included, the index data 123 becomes invalid. If the IDX section 602 corresponding to the category of the baseball program is included, it is determined whether or not there is a keyword segment 604 including a keyword name indicating a scoring scene. If it exists, the number of PTS units 609 included in the keyword segment 604 is obtained. When there is no keyword segment 604 including a keyword name indicating a scoring scene, the number of PTS units 609 is set to zero. Similarly, the number of PTS units 609 for the keyword name indicating the strikeout scene is obtained.

  As for the validity of the index data 123, when at least one of the score scene and the strikeout scene has a predetermined number of PTS units or more, it is determined that the index data 123 of the program is valid (step 903). .

  As described above, if it is determined that the index data 123 is valid and playback using subtitles is possible, a mark indicating that playback using subtitles for the Nth program is possible is displayed (step 904).

  Thereafter, the processing from step 902 to step 904 is performed for all programs, and when the processing for all programs is completed (step 905), the processing is terminated.

  Through the above steps, the user can know programs that can be index-reproduced using subtitles from the marks attached to the corresponding programs on the program list screen 800.

  As for the process of presenting to the user whether or not index reproduction using subtitles is possible, the validity of the index data 123 is determined for all programs every time the program list screen 800 is displayed in the above example. . Here, in order to reduce the load when displaying the program list screen 800, the validity determination result of the index data 123 is stored, for example, in the recorded program data 121, and the index reproduction is performed with reference to the determination result. Index reproducible marks 803 may be attached to possible programs. With this method, it is only necessary to determine the validity of the index data 123 once, and it is possible to reduce the load when the program list screen 800 is displayed.

  Further, in addition to the above method, the index data 123 may be deleted for a program that is determined to be incapable of index reproduction based on the validity determination result of the index data 123. When this method is performed and the program list screen 800 is displayed, if index data 123 exists, an index reproducible mark 803 is attached. Similarly, the load on displaying the program list screen 800 can be reduced by this method, and the free capacity of the external storage device 107 can be increased.

  Next, a user interface when the user performs index reproduction using subtitles will be described with reference to FIG.

  The program playback screen 1000 capable of index playback according to this embodiment includes an index selection menu 1001, a category selection menu 1002, a keyword input field 1003, a progress bar display unit 1004, and a program video display unit 1005.

  The program playback screen 1000 that can perform index playback according to the present embodiment is activated when a program with a star mark 803 in FIG. 9 is selected and the user instructs index playback using subtitles via the input device 103. The

  As shown in FIG. 10, the index selection menu 1001 is a menu for selecting an index to be used for reproduction by presenting to a user such as a home run or a score scene. The index is an index that is shown to the user for program playback. In the present embodiment, the index is described as matching the keyword in the subtitle, but the keyword is associated with a word or keyword that is related but is displayed separately. It is good also as a superordinate concept of the word to be performed or a keyword. When the program playback screen 1000 is displayed, the system control unit 110 makes a keyword list acquisition request to the keyword list acquisition unit 115 to acquire the index keyword to be presented in the index selection menu 1001. The IDX section 602 suitable for the category of the program is automatically selected from the index data 123 of the program, and all or a part of the keyword list is acquired from the keyword segment included in the IDX section 602, and the video output unit 118 To pass to.

  As will be described later, the category of the program can be selected by the user by the category selection menu 1002.

  Further, the keyword list acquisition unit 115 outputs only keywords having one or more PTS units. The video output unit 118 displays the acquired keyword list on the index selection menu 1001.

  When the user selects an index in the index selection menu 1001, the display content of the progress bar display unit 1004 also changes. On the progress bar display unit 1004, a progress bar indicating the entire program length and the chapter playback position corresponding to the selection content of the index selection menu 1001 are displayed as the index position 1006.

  When an index is selected again in the index selection menu 1001, a keyword corresponding to the index is input to the reproduction position list acquisition unit 116. The reproduction position list acquisition unit 116 selects the IDX section 602 corresponding to the category of the program from the index data 123 of the program, and selects all the PTS units from the keyword segment 604 corresponding to the input keyword included in the IDX section. To get. Subsequently, the acquired PTS unit 609 is transferred to the video output unit 118. The video output unit 118 displays the playback position of the corresponding chapter of the acquired PTS unit 609 on the progress bar. Here, when the PTS unit is type 1 (appearance time type) in FIG. 4, the video output unit 118 displays only the appearance position in a color different from the reference color of the professional glass bar. On the other hand, when the PTS unit is type 2 in FIG. 6, the section surrounded by the start / end times is displayed in a color different from the reference color of the professional glass bar. When the progress bar display unit 1004 receives a keyword reproduction request from the user via the input device 103, the progress bar display unit 1004 can jump to the chapter corresponding to the keyword and reproduce it.

  The category selection menu 1002 shows category names such as baseball and news as shown in FIG. 10, and the index keyword name presented in the index selection menu 1001 changes when the category is changed. By making a category list acquisition request to the keyword list acquisition unit 115 when the program program playback screen 1000 is displayed, all section IDs including valid keywords in the IDX section 602 included in the index data 123 of the program are displayed. To get. The acquired section ID is converted into a category name and output to the video output unit 118. The video output unit 118 displays the category name in the category selection menu 1002.

  When another category is selected in the category selection menu 1002, the IDX section 602 in the index data 123 is specified from the section ID corresponding to the category, and all or a part of the keyword list is included in the keyword segment included in the IDX section 602. Is obtained and passed to the video output unit 118. Further, the keyword list acquisition unit 115 outputs only keywords having one or more PTS units. Then, the video output unit 118 redisplays the acquired keyword list on the index selection menu 1001.

  The keyword input field 1003 is used to input a keyword that the user wants to search via the input device 103. This search is called “free keyword search”. The keyword input by the user is referred to as “free keyword”. When a keyword is input and a search start is instructed, a playback position list acquisition request for the keyword is sent to the playback position list acquisition unit 115. The reproduction position list acquisition unit 115 performs matching with keyword names of keyword segments in all IDX sections 602 included in the index data 123. If a matching keyword segment is found as a result of matching with the keyword name, the PTS unit of the keyword is output to the video output unit 118. The video output unit 118 reproduces the chapter corresponding to the position corresponding to the position of the PTS unit 609 or uses the position indicated by the PTS unit to display the video corresponding to the PTS unit on the progress bar display unit 1004. The position of can be displayed. On the other hand, if not found, a message display command indicating that nothing was found is sent to the video output unit 118.

  As described above, by automatically inputting a keyword to the user, a scene that the user wants to view manually can be searched. Further, by outputting as many IDX sections 602 as possible to the index data 123, the hit rate of the search keyword by the user can be increased.

  The program recording / playback apparatus according to the present embodiment generates the index data 123 from the digital broadcast subtitle data, but reflects the scene detection result other than the subtitle in the index data 123 by analyzing the video and audio. Also good. For example, it may be output as another IDX section using the telop recognition result in the video, the CM detection result, or the like.

  Further, when the program recording / playback apparatus and the recorded program data 121 in the embodiment are copied or moved from the external storage device 107 to another recording medium, the index data 123 may be moved simultaneously. For example, even a playback-only player can perform playback using subtitles by installing the keyword list acquisition unit 115 and the playback position acquisition unit 116.

[Embodiment 2]
Hereinafter, a second embodiment according to the present invention will be described with reference to FIG.

  In the first embodiment, when searching for free keywords, only the index data 123 is searched. The present embodiment provides a means that allows a search range to be searched at a high speed from all the captions ES included in the content.

  In the present embodiment, a description will be given with emphasis on different points compared to the first embodiment.

  FIG. 11 is a block diagram showing a configuration of a program recording / playback apparatus according to the second embodiment of the present invention.

  As shown in FIG. 11, the configuration of the program recording / playback apparatus of the present embodiment is different from that of the first embodiment in FIG. 1, where the caption analysis unit 112 outputs the caption address data 125. The caption address data 125 is an address list of TS packets including the caption ES among the TS packets included in the recorded program data 121.

  In the prior art, when a search using the free keyword is performed from the recorded program data 121, the location of the subtitle ES included in the recorded program data 121 cannot be specified. Therefore, when searching for the subtitle ES, it is necessary to analyze all packets. It took some time.

  In this embodiment, when a free keyword search is performed from the recorded program data 121, it is only necessary to analyze the packet at the address indicated in the subtitle address data 125, so that the search time can be greatly improved. .

  The subtitle address data 125 is generated during program recording. The process at the time of program recording in the program recording / playback apparatus according to the present embodiment is obtained by adding a process for generating subtitle address data 125 to the flowchart of FIG. 7 of the first embodiment. In this embodiment, the subtitle ES is delivered to the subtitle analysis unit 112 in step 701, and at the same time, the address in the recorded program data 121 of the TS packet including the subtitle ES is delivered. Since the TS packet in digital broadcasting has a fixed length of 188 bytes, a packet number may be used, but an actual address recorded in the actual external storage device 107 may be used.

  The caption analysis unit 112 outputs index data to the caption ES in step 705 and outputs the received TS packet address as caption address data 125.

  Next, a method for performing a free keyword search using the caption address data 125 will be described.

  The processing of the present embodiment is different only in that the target for the free keyword search is the addition of the recorded program data 121 and the caption address data 125 to the index data 123.

  First, as in the first embodiment, when a keyword is entered in the keyword input field 1003 and a search start is instructed, a playback position list acquisition request for the keyword is made to the playback position list acquisition unit 115, and an index is set. A free keyword search is performed on the data 123. The PTS unit 609 of the keyword for which the free keyword search has been performed is output to the video output unit 118.

  On the other hand, if not found, the address list of TS packets included in the subtitle address data 125 is acquired in order.

  Next, the TS packet included in the recorded program data 121 at the address is analyzed by the signal separation unit 111 and the caption ES is input to the caption analysis unit. The subtitle analysis unit 112 decodes the subtitle ES to obtain a subtitle sentence, and performs matching processing with the free keyword to be searched. If the free keyword to be searched is included in the caption text, the time stamp of the caption text is output to the RAM 106.

  Thereafter, processing is performed on all address lists of TS packets included in the caption address data 125.

  As a result of the above processing, if a free keyword is found in the caption text, the time stamp list is output to the video output unit 118. On the other hand, if not found, a message display command indicating that nothing was found is sent to the video output unit 118.

  In this embodiment, since the index data 123 is searched first, the high-speed search is maintained as in the first embodiment. In the present embodiment, the keyword hit rate is improved because the subtitle sentence itself can be searched at high speed even if it is not found in the free keyword search for the index data 123. Further, since the data stored in the external storage device 107 is merely a packet address of a TS packet including a caption ES, there is no problem with copyright.

[Embodiment 3]
Hereinafter, a third embodiment according to the present invention will be described with reference to FIG.

  In the second embodiment, in the search by the user's free keyword, the recorded program data 121 is searched with reference to the subtitle address data 125 in addition to the index data 123. In the present embodiment, the caption ES is stored as data different from the recorded program data. This is not a problem with copyright because it does not copy the caption text itself to an external medium.

  Note that this embodiment will also be described with emphasis on differences from the first embodiment.

  FIG. 12 is a block diagram showing a configuration of a program recording / playback apparatus according to the third embodiment of the present invention.

  As shown in FIG. 12, the configuration of the program recording / playback apparatus according to the present embodiment is different from that of the first embodiment shown in FIG. 1, in which the caption analysis unit 112 outputs the caption PES data 126. The caption PES data is obtained by sequentially outputting PES packets including the caption ES.

  The caption PES data 126 is generated during program recording. The processing at the time of program recording in the program recording / playback apparatus in the present embodiment is obtained by changing the processing related to the caption PES data 126 in the flowchart of FIG. 7 of the first embodiment. In this embodiment, when the recorded program data is output to the program recording unit 113 in the process of step 701 in FIG. 7, the TS packet including the caption ES is filtered and not transferred. Also, the caption analysis unit 121 acquires a PES packet from the received TS packet including the caption ES and outputs it as caption PES data 126.

  In the present embodiment, at the time of broadcasting, the ES related to the caption is separated and stored in the external storage device 107. When the recorded data is reproduced, the caption PES data 126 is displayed as a PES packet in order to display the caption. It is necessary to input directly to the program playback unit 117.

  Next, a method for performing a free keyword search using the caption PES data 126 will be described.

  In the processing of the second embodiment, the target for the free keyword search is that the recorded program data 121 and the caption address data 125 are added to the index data 123.

  In the processing of this embodiment, the target for the free keyword search is the index data 123 and the caption PES data 126 added.

  First, as in the first and second embodiments, when a keyword is entered in the keyword input field 1003 and a search start is instructed, a reproduction position list acquisition request for the keyword is sent to the reproduction position list acquisition unit 115. Perform a free keyword search for the index data 123. The PTS unit 609 of the keyword for which the free keyword search has been performed is output to the video output unit 118.

  On the other hand, if not found, the PES packets included in the caption PES data 126 are acquired in order. Subsequently, the PES packet is input to the caption analysis unit 112. The subtitle analysis unit 112 decodes the subtitle ES to obtain a subtitle sentence, and performs matching processing with the free keyword to be searched. If the free keyword to be searched is included in the caption text, the time stamp of the caption text is output to the RAM 106. Thereafter, the processing is performed on all packets included in the caption PES data 126.

  As a result of the above processing, if a free keyword is found in the caption text acquired from the caption PES data 126, the time stamp list is output to the video output unit 118. On the other hand, if not found, a message display command indicating that nothing was found is sent to the video output unit 118.

  Compared with the second embodiment, the free keyword search in the present embodiment stores the PES packet related to the caption as a series of data in the external storage device 107, and therefore the number of times of data seek at the time of the search is small and high speed. It is.

It is a block diagram which shows the structure of the program recording / reproducing apparatus which concerns on 1st embodiment of this invention. It is a figure which shows the data structure of the data stream in digital broadcasting. It is a figure which shows the format of caption text data. It is a figure which shows the data structure of the index data 123. FIG. It is a flowchart which shows the process which the index production | generation part 114 produces | generates index data. It is a flowchart which shows the detail of an index data output process. It is a flowchart which shows the process at the time of program recording. It is a flowchart which shows the process which shows to a user whether the index reproduction | regeneration with the keyword contained in a subtitle is possible. It is a figure which shows the program list screen at the time of showing to the user whether index reproduction by subtitles is possible. It is a figure which shows the example of the user interface of the program reproduction | regeneration screen which performs index reproduction | regeneration using a subtitle. It is a block diagram which shows the structure of the program recording / reproducing apparatus which concerns on 2nd embodiment of this invention. It is a block diagram which shows the structure of the program recording / reproducing apparatus which concerns on 3rd embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 ... Recording / reproducing part, 102 ... Display apparatus, 103 ... Input device, 104 ... Tuner, 105 ... Antenna, 106 ... RAM, 107 ... External storage device,
DESCRIPTION OF SYMBOLS 110 ... System control part, 111 ... Signal separation part, 112 ... Subtitle analysis part, 113 ... Program recording part, 114 ... Index generation part, 115 ... Keyword list acquisition part, 116 ... Reproduction position list acquisition part, 117 ... Program reproduction part 118 ... Video output section,
120 ... subtitle sentence data, 121 ... recorded program data, 122 ... dictionary data, 123 ... index data,
125: Subtitle address data,
126 ... Subtitle PES data,
800 ... Program list screen, 801 ... Thumbnail, 802 ... Program information, 803 ... Index playable mark,
1000 ... Program playback screen, 1001 ... Index selection menu, 1002 ... Category selection menu, 1003 ... Keyword input field, 1004 ... Progress bar display section, 1005 ... Program video display section, index position 1006.

Claims (10)

A signal separator that receives digital broadcasts and separates them according to the type of broadcast data;
A subtitle analysis unit that analyzes subtitle ES (Elementary Stream) input from the signal separation unit and generates subtitle sentence data including a subtitle sentence, a control code, and a display time;
A program recording unit that records the broadcast data input from the signal separation unit as recording data in a storage device;
An index generation unit that analyzes the caption text data, generates index data for reproducing a program according to an index specified by a user, and outputs the index data to a storage device;
A keyword list acquisition unit for acquiring a keyword list as an index candidate from the index data;
A playback position list acquisition unit that searches the index data and acquires a playback position list for a playback position for a keyword selected from the keyword list;
When playing back a recorded program, it is displayed which part of the program corresponds to the index keyword specified by the user, and the recorded data at the position corresponding to the index keyword specified by the user is played back. A program recording / playback apparatus. Furthermore, the user has means for inputting a keyword,
The playback position list acquisition unit searches the index data for the input keyword to acquire a playback position list,
2. When reproducing a recorded program, it is displayed which part of the program corresponds to the position corresponding to the inputted keyword, and the recorded data at the position corresponding to the inputted keyword is reproduced. The program recording / playback apparatus described. Furthermore, the user has means for selecting a program category,
The index data has an area for holding another keyword for each program category,
When playing back a recorded program, it displays which part of the program the position corresponding to the keyword of the category selected by the user, and plays back the recorded data at the position corresponding to the keyword of the category selected by the user. The program recording / reproducing apparatus according to claim 1 or 2, wherein: The caption analysis unit extracts the address of a TS (Transport Stream) packet including the caption ES input from the signal separation unit, generates caption address data including the address of the TS packet including the caption ES, and stores the storage device Output to
3. The program recording / playback apparatus according to claim 2, wherein the playback position list acquisition unit searches the subtitle address data for the input keyword and acquires a playback position list. The caption analysis unit generates caption PES (Packetized Elementary Stream) data including the caption ES input from the signal separation unit, and outputs the data to a storage device.
The program recording / playback apparatus according to claim 2, wherein the playback position list acquisition unit searches the subtitle PES data for the input keyword and acquires a playback position list. A signal separator that receives the digital broadcast and separates it according to the type of broadcast data;
A subtitle analysis unit that analyzes the subtitle ES (Elementary Stream) input from the signal separation unit and generates subtitle sentence data including a subtitle sentence, a control code, and a display time;
A program recording unit recording the broadcast data input from the signal separation unit as recording data in a storage device;
An index generation unit that analyzes the caption sentence data and generates index data for reproducing a program according to an index specified by a user;
A keyword list obtaining unit obtaining a keyword list as index candidates from the index data; and
A reproduction position list acquisition unit, for the reproduction position for the keyword selected from the keyword list, to retrieve the reproduction position list by searching from the index data;
From the program playback screen, inputting the keyword of the index specified by the user;
Displaying on the program playback screen which part of the program the position corresponding to the index keyword specified by the user is;
Replaying recorded data at a position corresponding to a keyword of an index designated by the user. Furthermore, the user inputs a keyword,
The reproduction position list acquisition unit searching the index data for the input keyword to acquire a reproduction position list;
Displaying a portion of the program corresponding to the input keyword when playing the recorded program; and
7. The program recording / reproducing method according to claim 6, further comprising the step of reproducing the recorded data at a position corresponding to the inputted keyword. And a user selecting a program category;
Displaying the portion of the program corresponding to the keyword of the category selected by the user in playing the recorded program;
8. The program recording / reproducing method according to claim 6, further comprising a step of reproducing the recorded data at a position corresponding to the keyword of the category selected by the user. The caption analysis unit extracts the address of a TS packet including the caption ES input from the signal separation unit, generates caption address data including the address of a TS (Transport Stream) packet including the caption ES, and a storage device A step to output to
The playback position list acquisition unit includes a step of searching the input keyword from the index and, if not found, searching from the subtitle address data to acquire a playback position list. 8. The program recording / reproducing method according to claim 7, The subtitle analysis unit generates subtitle PES (Packetized Elementary Stream) data including the subtitle ES input from the signal separation unit, and outputs to the storage device;
The reproduction position list acquisition unit retrieves the input keyword from the index PES data by searching the input keyword when the input keyword is not found. The program recording / reproducing method according to claim 7, further comprising:

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