JP5354664B2 - Digital data receiver and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To determine either 1-segment broadcast or 12-segment broadcast and to switch both broadcasts without uncomfortable feeling for simulcast. <P>SOLUTION: Caption data of 1-segment broadcast and 12-segment broadcast are received to search for caption PES (Packetized Elementary Stream) data with identical caption data. When the identical caption data is found, the simulcast is recognized to analyze a time difference of presentation timing of each broadcast data by comparing presentation information of each caption PES data and PTS (Presentation Time Stamp). A broadcast switching control part 404 monitors a broadcast reception level to determine a broadcast switching of 1-segment broadcast and 12-segment broadcast and outputs it as switched data to a broadcast switching part 412. A timing control part 405 receives information on a broadcast timing difference of the 1-segment broadcast and 12-segment broadcast analyzed by the broadcast switching control part 404, and controls the start timing of decoding the PES data stored in a buffer to correct the time difference. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a digital data receiver such as a digital broadcast receiver capable of switching and using a plurality of types of reception services, and a program.

  In Japanese terrestrial digital broadcasting, one channel is divided into 13 segments for transmission. Among the 13 segments, broadcasting using one central segment is called “1 segment broadcasting”, and broadcasting using 12 segments is called “12 segment broadcasting”. It is in operation. There are two types of broadcasting, 1-segment broadcasting and 12-segment broadcasting, in which broadcasting of programs with the same content (hereinafter referred to as simulcasting) is performed and in broadcasting of different programs in each broadcasting.

  One-segment broadcasting cannot transmit high-quality data, but has high reception stability, and is used, for example, as a broadcast for mobile terminals. On the other hand, 12-segment broadcasting can transmit high-quality data but has low reception stability, and is therefore used, for example, as a broadcast for fixed terminals.

  In 1-segment broadcasting and 12-segment broadcasting, different signal layers are subjected to different encoding processes, and are multiplexed for each broadcast and transmitted from an antenna. A broadcast timing difference of the broadcast signal occurs. Therefore, even in the same scene of the simulcast that provides the same content program in the 1-segment broadcast and the 12-segment broadcast, there is a time difference between the viewing timing of several milliseconds to several seconds in the 1-segment broadcast and the 12-segment broadcast. Will occur.

  The time difference between broadcast signals of several milliseconds to several seconds (hereinafter referred to as “broadcast timing difference”) generated between each broadcast of 1-segment broadcast and 12-segment broadcast is suppressed and viewed while switching between broadcasts (hereinafter switched viewing) Digital broadcast receivers that can be referred to) have been proposed (see, for example, Patent Document 1).

  The digital broadcast receiver described in Patent Document 1 measures the time at which video scenes of 1-segment broadcast and 12-segment broadcast are switched when switching between broadcasts. Also, the broadcast timing difference is analyzed by comparing the measured times. Then, when viewing is switched to the earlier broadcasting timing of 1-segment broadcasting or 12-segment broadcasting, the switching viewing is performed while delaying the time corresponding to the difference in broadcasting timing, thereby suppressing the shift of the video.

  In addition, by determining whether the 1-segment broadcast and the 12-segment broadcast are the same program, it is determined whether or not the programs of each broadcast are the same (simultaneous broadcast). An implementation method has been proposed (referred to as Patent Document 2).

  In the simulcast determination described in Patent Document 2, the audio data of 1-segment broadcasting and 12-segment broadcasting are compared and their correlation is analyzed. When the correlation is high, it is determined that the broadcast is simultaneous, and when the correlation is low, it is determined that the broadcast is non-simultaneous.

JP 2008-92100 A JP 2007-295470 A

  In order to seamlessly switch the simulcast while suppressing the broadcast timing difference between the 1-segment broadcast and the 12-segment broadcast, the Patent Document 1 and Patent Document 2 analyze the broadcast timing difference by comparing video data and audio data. Had gone. Since the data broadcast in the 1-segment broadcast or the 12-segment broadcast is mainly video and audio, the broadcast timing difference can be analyzed while receiving these data.

  However, when searching for video data and audio data of the same scene from the broadcast data of 1-segment broadcasting and 12-segment broadcasting, the video is subjected to a comparison operation of resolution and contrast. On the other hand, for voice, comparison operations such as pitch and tempo are required. There is a concern that these comparison operations require a large load on device operation.

  The present invention has been made in view of the above circumstances, and preferably determines whether or not a 1-segment broadcast and a 12-segment broadcast are simultaneous broadcasts. An object of the present invention is to provide a digital data receiver and a program that can be switched with reduced deviation from broadcasting.

To achieve the above object, digital data receiver of the present invention,
Broadcast receiving means for receiving first broadcast data and second broadcast data from a broadcast wave;
Caption data extraction means for extracting caption data corresponding to each broadcast data from the first broadcast data and the second broadcast data received by the broadcast receiving means;
By comparing the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extracting means and the second subtitle data corresponding to the second broadcast data, the first subtitle data is extracted. Subtitle data analysis means for measuring a time difference between broadcast data and the second broadcast data;
Equipped with a,
The caption data analysis means includes
By searching for the same scene using text data included in the first subtitle data and the second subtitle data, and comparing the time when each subtitle data of the searched scene is presented, Measuring the time difference between the broadcast data and the second broadcast data;
In the text data included in the first subtitle data and the second subtitle data, it is determined whether or not they are the same scene by calculating a ratio including the same characters.
And wherein a call.

The digital data receiver of the present invention is
Broadcast receiving means for receiving first broadcast data and second broadcast data from a broadcast wave;
Caption data extraction means for extracting caption data corresponding to each broadcast data from the first broadcast data and the second broadcast data received by the broadcast receiving means;
By comparing the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extracting means and the second subtitle data corresponding to the second broadcast data, the first subtitle data is extracted. Subtitle data analysis means for measuring a time difference between broadcast data and the second broadcast data;
With
The subtitle data analyzing means searches for a similar pattern portion in which a time interval pattern for presenting the first subtitle data and a time interval pattern for presenting the second subtitle data are similar to each other, By calculating the time difference between the similar pattern portions, the time difference between the first broadcast data and the second broadcast data is measured .

The digital data receiver of the present invention is
Broadcast receiving means for receiving first broadcast data and second broadcast data from a broadcast wave;
Caption data extraction means for extracting caption data corresponding to each broadcast data from the first broadcast data and the second broadcast data received by the broadcast receiving means;
By comparing the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extracting means and the second subtitle data corresponding to the second broadcast data, the first subtitle data is extracted. Subtitle data analysis means for measuring a time difference between broadcast data and the second broadcast data;
With
The subtitle data analyzing means measures a time difference between the first broadcast data and the second broadcast data when a program received by the broadcast receiving means changes .

First decoding means for decoding the first broadcast data;
Second decoding means for decoding the second broadcast data;
Timing control means for controlling the timing of starting decoding of each of the broadcast data;
A simulcast broadcast discriminating means for discriminating whether or not the first broadcast data and the second broadcast data are simulcast broadcast data;
The timing control means, when it is determined that the first broadcast data and the second broadcast data are the broadcast data of the simulcast, the first broadcast data measured by the caption data analysis means You may make it control the decoding start timing of each said broadcast data based on the time difference with said 2nd broadcast data.

  The timing control means accumulates the data amount corresponding to the time difference in the buffer for the broadcast data with the earlier reception timing out of the first broadcast data and the second broadcast data, and sets the decoding start timing. It may be delayed.

  The simulcast discrimination unit compares the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extraction unit and the second subtitle data corresponding to the second broadcast data. Thus, it may be determined whether or not the data is simulcast broadcast data.

The digital data receiver of the present invention is
Broadcast receiving means for receiving first broadcast data and second broadcast data from a broadcast wave;
Caption data extraction means for extracting caption data corresponding to each broadcast data from the first broadcast data and the second broadcast data received by the broadcast receiving means;
By comparing the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extracting means and the second subtitle data corresponding to the second broadcast data, the first subtitle data is extracted. Subtitle data analysis means for measuring a time difference between broadcast data and the second broadcast data;
When the caption data cannot be extracted by the caption data extraction means, the first broadcast data and the second broadcast data are based on video data or audio data included in the first broadcast data and the second broadcast data. a time difference measuring means for measuring a time difference between the broadcast data,
Is provided.

Program of the present invention, a computer,
Broadcast receiving means for receiving first broadcast data and second broadcast data from a broadcast wave;
Caption data extraction means for extracting caption data corresponding to each broadcast data from the first broadcast data and the second broadcast data received by the broadcast receiving means;
By comparing the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extracting means and the second subtitle data corresponding to the second broadcast data, the first subtitle data is extracted. Subtitle data analysis means for measuring a time difference between broadcast data and the second broadcast data;
To function as,
The caption data analysis means includes
By searching for the same scene using text data included in the first subtitle data and the second subtitle data, and comparing the time when each subtitle data of the searched scene is presented, Measuring the time difference between the broadcast data and the second broadcast data;
In the text data included in the first subtitle data and the second subtitle data, it is determined whether or not they are the same scene by calculating a ratio including the same characters.
And wherein a call.
The program of the present invention is a computer,
Broadcast receiving means for receiving first broadcast data and second broadcast data from a broadcast wave;
Caption data extraction means for extracting caption data corresponding to each broadcast data from the first broadcast data and the second broadcast data received by the broadcast receiving means;
By comparing the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extracting means and the second subtitle data corresponding to the second broadcast data, the first subtitle data is extracted. Subtitle data analysis means for measuring a time difference between broadcast data and the second broadcast data;
Function as
The subtitle data analyzing means searches for a similar pattern portion in which a time interval pattern for presenting the first subtitle data and a time interval pattern for presenting the second subtitle data are similar to each other, The time difference between the first broadcast data and the second broadcast data is measured by calculating the time difference between the similar pattern portions.
It is characterized by that.
The program of the present invention is a computer,
Broadcast receiving means for receiving first broadcast data and second broadcast data from a broadcast wave;
Caption data extraction means for extracting caption data corresponding to each broadcast data from the first broadcast data and the second broadcast data received by the broadcast receiving means;
By comparing the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extracting means and the second subtitle data corresponding to the second broadcast data, the first subtitle data is extracted. Subtitle data analysis means for measuring a time difference between broadcast data and the second broadcast data;
Function as
The caption data analyzing means measures a time difference between the first broadcast data and the second broadcast data when a program received by the broadcast receiving means changes.
It is characterized by that.
The program of the present invention is a computer,
Broadcast receiving means for receiving first broadcast data and second broadcast data from a broadcast wave;
Caption data extraction means for extracting caption data corresponding to each broadcast data from the first broadcast data and the second broadcast data received by the broadcast receiving means;
By comparing the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extracting means and the second subtitle data corresponding to the second broadcast data, the first subtitle data is extracted. Subtitle data analysis means for measuring a time difference between broadcast data and the second broadcast data;
When the caption data cannot be extracted by the caption data extraction means, the first broadcast data and the second broadcast data are based on video data or audio data included in the first broadcast data and the second broadcast data. Time difference measuring means for measuring the time difference from the broadcast data of
It is made to function as.

  ADVANTAGE OF THE INVENTION According to this invention, the smooth switching viewing which suppressed the time difference of the broadcast timing of 1 segment broadcast and 12 segment broadcast is realizable. In addition, switching viewing can be performed while reducing the load of device operation and suppressing power consumption.

It is a figure which shows the outline | summary of the system of the transmitter which produces broadcast data, such as an image | video, an audio | voice, and a caption. It is the schematic explaining the structure of broadcast data. It is a figure which shows the system outline | summary of the receiver which receives TS data and reproduces | regenerates a video, an audio | voice, and a subtitle synchronously. 2 is a functional block diagram of a broadcast receiver according to Embodiment 1. FIG. It is a functional block diagram of a timing control part. It is a functional block diagram of a broadcast switching control unit. It is a flowchart which shows the operation | movement of a broadcast timing difference analysis process. It is a flowchart which shows the operation | movement of a broadcast switching process. It is a flowchart which shows the flow from the state in which the broadcast receiver is receiving 1 segment broadcast as an example of operation | movement of a broadcast switching part to switching broadcast to 12 segment broadcast. It is a figure which shows the flow of the data from the buffer of a timing control part to a decoding part. It is a functional block diagram of the broadcast receiver of Embodiment 2. It is a block diagram of a broadcast switching control unit. 12 is a timing chart in which subtitle PES data of 12-segment broadcasting and 1-segment broadcasting is stored for the same time and mapped on time according to time information indicated by PTS. It is a flowchart which shows the operation | movement of the timing difference analysis process which performs PTS pattern matching using the mapping data of subtitles PTS shown in FIG.

  Hereinafter, a broadcast receiver according to the present invention will be described with reference to the drawings. First, a mechanism for synchronously reproducing broadcast data such as video, audio, and subtitles that is generally put into practical use in the broadcast standard with a receiver will be described below with reference to FIGS. 1 to 3.

  FIG. 1 shows an overview of a system of a transmitter 10 that creates broadcast data such as video, audio, and captions. FIG. 2 shows an outline of the structure of broadcast data transmitted by the transmitter 10.

  As shown in FIG. 1, the transmitter 10 includes a video encoding unit 1, an audio encoding unit 2, a subtitle encoding unit 3, a TS encoding unit 4, and an STC (System Time Clock) 5.

  When the transmitter 10 transmits broadcast data, first, video, audio, and subtitle data corresponding to the broadcast are encoded by the video encoding unit 1, the audio encoding unit 2, and the subtitle encoding unit 3, respectively, and then the PES (Packetized Elementary Stream). ) Data 21 is created. In each of the encoding units 1 to 3, when creating the PES data 21, time information indicating the reproduction time of video, audio, and subtitle data called PTS (Presentation Time Stamp) 22 is described in the PES header 23. Then, the PES header 23 and the PES data 21 are combined into one variable-length packet called a PES packet 24 (see FIG. 2).

  The PTS 22 acquires reference time information on the operation of the transmitter 10 itself from the STC 5 when the encoding units 1 to 3 perform encoding, and is created based on the reference time. The video, audio, and caption PES data 21 in which the same PTS 22 is described corresponds to the same scene data.

  Finally, the TS encoder unit 4 transmits the PES packet 24 as broadcast data in a form multiplexed with TS (Transport Stream) data 25.

  When creating the TS data 25, the TS header 26, which is the header portion of the TS data 25, is multiplexed including a reference value of a clock on the transmitting side called a PCR (Program Clock Reference) 27 (see FIG. 2). In this way, the receiver that receives the TS data 25 can synchronize its own STC with the STC on the transmitter side with reference to the PCR 27.

  Next, the operation on the receiver side that receives broadcast data will be described. FIG. 3 shows a system overview of a general receiver 30 that receives TS data 25 and synchronously reproduces video, audio, and subtitles. The receiver 30 includes a receiving unit 301, a TS decoding unit 302, a timing control unit 307, a video decoding unit 308, an audio decoding unit 309, a caption decoding unit 310, and an STC 311. The timing control unit 307 includes a buffer control unit 303, a video buffer 304, an audio buffer 305, and a caption buffer 306.

  The receiving unit 301 demodulates the broadcast signal received via the antenna into the TS data 25 and outputs it to the TS decoding unit 302. The TS decoding unit 302 demultiplexes the received TS data 25 and temporarily stores the video, audio, and subtitle PES data 21 in the video buffer 304, audio buffer 305, and subtitle buffer 306, respectively. Further, the TS decoding unit 302 separates the PCR 27 from the received TS data 25 and uses it to synchronize the STC 311 that is the reference clock on the receiver 30 side with the STC 5 on the transmitter 10 side. Each PES data 21 includes the PTS 22 indicating the reproduction time in the header as described above.

  The buffer control unit 303 controls the timing of sending each PES data 21 from each buffer 304 to 306 to each decoding unit 308 to 310. When the time information of the STC 311 comes to the timing of the PTS 22, the buffer control unit 303 sends the PES data 21 from the buffers 304 to 306 to the decoding units 308 to 310, and the decoding units 308 to 310 transmit video, audio, and subtitles. The scene is synchronized and decoded. Finally, the decoded video, audio, and subtitle data is displayed and reproduced on an output device such as a monitor or a speaker, so that the user can view the data.

  The PES packet 24 may include a DTS (Decoding Time Stamp) indicating a decoding start time in addition to the PTS 22 that is presentation information. When the DTS is described in the PES data 21, the decoding start timing can be determined with reference to the time and the STC 311.

  On the receiver 30 side, due to fluctuations in the amount of data such as video and audio, a delay occurs when temporarily storing data in a buffer and when reading data from the buffer. In order to compensate for these delays, the largest delay time from the time each data is temporarily stored in the buffer to the time the data is read out is referred to as the common delay time (hereinafter referred to as the common delay time). ). Then, decoding is performed at a timing further delayed by the common delay time from the time of the PTS 22 and the DTS, so that reproduction of data such as moving images, audio, and subtitles can be performed with the same delay.

  Since the STC 5 on the transmission side is set for each broadcasting station, the broadcasting time may be different for each broadcasting station. Further, even when the same broadcasting station performs simultaneous broadcasting with 1-segment broadcasting and 12-segment broadcasting, different transmitters are used when creating data for 1-segment broadcasting and 12-segment broadcasting. Thereby, STC5 also becomes different time by each broadcast, and a broadcast timing difference may arise.

(Embodiment 1)
Next, the broadcast receiver in Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 4 is a block diagram showing an outline of the broadcast receiver 40 in the present invention. The broadcast receiver 40 includes a receiving unit 401, a 1-segment TS decoding unit 402, a 12-segment TS decoding unit 403, a broadcast switching control unit 404, a timing control unit 405, a 1-segment video decoding unit 406, and a 1-segment audio decoding. 407, a 1-segment subtitle decoding section 408, a 12-segment video decoding section 409, a 12-segment audio decoding section 410, a 12-segment subtitle decoding section 411, a broadcast switching section 412, and a monitor 413.

  The receiving unit 401 demodulates the broadcast signal received via the antenna into TS data. Then, receiving section 401 outputs 1-segment broadcasting TS data to 1-segment TS decoding section 402. The receiving unit 401 outputs 12-segment broadcasting TS data to the 12-segment TS decoding unit 403. The reception unit 401 outputs broadcast reception level information such as CNR (Carrier to Noise Ratio) and BER (Bit Error Rate) indicating the reception level of broadcast data to the broadcast switching control unit 404.

  The 1-segment TS decoding unit 402 demultiplexes 1-segment broadcast TS data, and outputs PES data of moving images, audio, and captions to the timing control unit 405. Similarly, the 12-segment TS decoding unit 403 demultiplexes the 12-segment broadcasting TS data and outputs each PES data to the timing control unit 405.

  The broadcast switching control unit 404 monitors broadcast reception level information received from the reception unit 401 and selects a broadcast to be reproduced from the 1-segment broadcast and the 12-segment broadcast. Then, the broadcast switching control unit 404 outputs the selected broadcast information to the broadcast switching unit 412 as switching information. Also, the broadcast switching control unit 404 analyzes the broadcast timing difference between the 1-segment broadcast and the 12-segment broadcast described above.

  The configuration of the timing control unit 405 will be described with reference to FIG. The timing control unit 405 includes a 1-segment video buffer 51, a 1-segment audio buffer 52, a 1-segment subtitle buffer 53, a 12-segment video buffer 54, a 12-segment audio buffer 55, a 12-segment subtitle buffer 56, and a buffer control unit 57. .

  The timing control unit 405 stores the video, audio, and subtitle PES data created by demultiplexing the 1-segment broadcasting TS data by the 1-segment TS decoding unit 402 in the respective buffers 51, 52, and 53.

  In addition, the timing control unit 405 demultiplexes the 12-segment broadcasting TS data by the 12-segment TS decoding unit 403, and the resulting PES data of the 12 broadcasting video, audio, and subtitles is stored in the respective buffers 54, Accumulate at 55 and 56. The buffer control unit 57 controls the output timing of the PES data from the buffer units 51 to 56 to the decoding units 406 to 41 1 in order to decode the PES data stored in the buffers.

  The buffer control unit 57 receives information on the broadcast timing difference between the 1-segment broadcast and the 12-segment broadcast analyzed by the broadcast switching control unit 404. Then, when switching between broadcasts, the buffer control unit 57 suppresses the broadcast timing difference among the broadcasts, so that the decoding start timing with the earlier broadcast timing is set to the PTS corresponding to the broadcast timing difference. Delay from the original time shown.

  The video, audio, and subtitle decoding units 406 to 411 decode various PES data and output them to the broadcast switching unit 412.

  The broadcast switching unit 412 receives data such as video, audio and subtitles decoded from the decoding units 406 to 411 and displays and reproduces each data on the monitor 413. The broadcast switching unit 412 has a function of switching between broadcasts to be displayed and reproduced between 1-segment broadcasts and 12-segment broadcasts. The broadcast switch control unit 404 selects 1-segment broadcasts and 12-segment broadcasts based on the switching information selected. Switch to segment broadcasting and output to the monitor 413.

  The monitor 413 has a video display and audio output function, receives various data such as video, audio, and subtitles from the broadcast switching unit 412 and performs display reproduction.

  The broadcast switching control unit 404 and the buffer control unit 57 are a ROM (Read Only Memory) that stores a program for realizing the functions of each control unit, a CPU (Central Processing Unit) that executes the program, a CPU work The area is composed of a RAM (Random Access Memory).

  A method for analyzing a broadcast timing difference in the broadcast switching control unit 404 will be described with reference to FIGS. FIG. 6 shows functional blocks of the broadcast switching control unit 404. The broadcast switching control unit 404 includes a caption data analysis unit 61, a reception status analysis unit 62, and a switching determination unit 63. The subtitle data analysis unit 61 analyzes the broadcast timing difference.

  FIG. 7 is a flowchart showing the operation of timing difference analysis processing from when the broadcast receiver 40 receives broadcast data of 1-segment broadcasting and 12-segment broadcasting until the caption data analysis unit 61 analyzes the broadcast timing difference. is there. The caption data analysis unit 61 includes the above-described STC that is the reference time of the operation system. However, since there is a possibility that the STC of the 1-segment broadcasting and the 12-segment broadcasting on the transmitter side are different, first, the caption data analysis unit 61 compares the STCs of the 1-segment broadcasting and the 12-segment broadcasting, and the reference time Timing difference (hereinafter referred to as a reference time difference) is obtained (step S701).

  Next, by comparing the PTS included in each PES data of the 1-segment broadcasting and the 12-segment broadcasting, a difference in time when each data is decoded and presented to the monitor 413 (hereinafter referred to as a presentation time difference) is obtained. . At this time, it is necessary to compare PTSs corresponding to PES data of the same scene. Therefore, in the present invention, subtitled PES data (hereinafter referred to as subtitle PES data) is used instead of video and audio data. In this way, it is possible to search for PES data of the same scene with a lower processing load than a method using video and audio. The caption PES data includes presentation control information such as a presentation position, character color, and character size, and text data indicating a caption text to be presented (hereinafter referred to as caption text) in addition to the PTS representing the presentation time to the monitor 413 described above. Data).

  A method for searching for subtitle PES data of the same scene will be described below. The subtitle data analysis unit 61 extracts subtitle text data C1, which is subtitle text data corresponding to one specific decoded scene, from the 12-segment subtitle decoding unit 411 (step S702). Next, the caption data analysis unit 61 extracts the decoded caption text data C2 corresponding to one specific scene from the 1-segment caption decoding unit 408 as in the case of 12-segment broadcasting (step S703).

  Then, the caption data analysis unit 61 compares the caption text data C1 and C2, and determines whether or not the caption text data is the same scene (step S704). The method for determining whether or not the caption text data is in the same scene can be realized by, for example, comparing the caption text data C1 and C2 from the first character to the last in order. However, some character sets that can be used for subtitles of 1-segment broadcasting and 12-segment broadcasting differ depending on the broadcast standard, and there are characters that can be used only for subtitles of 12-segment broadcasting. For this reason, even if not all characters are the same, if the same characters are included in each text in a certain ratio, they are determined to be the same sentence and determined to be PES in the same scene. good.

  When the subtitle text data C1 and C2 are not subtitle text data of the same scene (step S704; No), the subtitle data analysis unit 61 sets the subtitle data received next to the compared subtitle data for 1 segment broadcasting to 1 segment. It is obtained from the subtitle decoding unit 408, and again it is determined whether or not it is subtitle text data of the same scene, and this is repeated until subtitle text data of the same scene is found (steps S703 to S705).

  Here, it is determined that the data at which the subtitle data to be compared is received is far away from the assumed 12-segment broadcast and the 1-segment broadcast, which is a few seconds, which is the broadcast timing difference between the sub-segment broadcasts. The analysis process may be interrupted.

  When caption PES data having the same caption text data C1 and C2 is found (step S704; Yes), the caption data analysis unit 61 compares the PTS described in the PES header of each caption PES packet, and presents the presentation time. The difference is analyzed (step S706).

  Thereafter, the caption data analysis unit 61 adds up the analyzed reference time difference and presentation time difference to determine whether the 12-segment broadcast program and the 1-segment broadcast program are simultaneous broadcasts, and broadcast timing between the broadcasts. The difference is analyzed (step S707). The caption data analysis unit 61 notifies the broadcast switching unit 412 of the analyzed broadcast timing difference information.

  In the present embodiment, subtitle text data of 1 segment broadcast that is the same as specific subtitle text data of 12 segment broadcasting is searched, but conversely, 12 segment broadcasting that is the same as specific subtitle text data of 1 segment broadcast is searched. It is also possible to search for subtitle text data.

  If the same caption text data is not found in the broadcast data of 1-segment broadcasting and 12-segment broadcasting, it can be determined that the first and second programs are not the same program, that is, are not simulcast. . When this result is obtained, reception switching between 1-segment broadcasting and 12-segment broadcasting described later is not performed.

  Next, a method for correcting the time difference at the time of switching between the 1-segment broadcast and the 12-segment broadcast using the broadcast timing difference analyzed by the caption data analysis unit 61 will be described.

  In the functional block of the broadcast switching control unit 404 shown in FIG. 6, the reception status analysis unit 62 analyzes each reception level of the 1-segment broadcasting and the 12-segment broadcasting, and the switching determination unit 63 determines the broadcast switching unit 412. Instruct switching.

  FIG. 8 is a flowchart showing the operation of a broadcast switching process for performing broadcast switching according to the reception level of 1-segment broadcasting and 12-segment broadcasting. First, the reception status analysis unit 62 acquires the CNR and BER of the 1-segment broadcast and the 12-segment broadcast from the reception unit 401 (step S801). At this time, if it can be determined that the reception of the 12-segment broadcast is good from the values of CNR and BER (step S802; Yes), the reception status analysis unit 62 selects viewing of the 12-segment broadcast (step S803).

  On the other hand, if the reception level of the 12-segment broadcast is low and only the 1-segment broadcast is received well (step S802; No), the reception status analysis unit 62 selects viewing of the 1-segment broadcast (step S804). If both the 12-segment broadcasting and the 1-segment broadcasting are in poor reception status, they cannot be viewed together, so neither broadcasting is selected. Alternatively, in this case, the 1-segment broadcasting with high reception stability may be selected, and the reception status may be sequentially monitored to monitor when the reception status is good.

  The switching determination unit 63 receives the broadcast selection result of the reception status analysis unit 62 and instructs the broadcast switching unit 412 to switch.

  FIG. 9 is a flowchart showing a flow from the state in which the broadcast receiver is receiving the 1-segment broadcast to the broadcast switching to the 12-segment broadcast as an operation example of the broadcast switching unit 412. The broadcast receiver 40 receives the 1-segment broadcast at the receiving unit 401, decodes the received data according to the PTS, and outputs the decoded data to the monitor 413 (step S901). Subsequently, the broadcast receiver 40 starts reception of the 12-segment broadcast at the reception unit 401, monitors the reception status, analyzes the broadcast timing difference between the 1-segment broadcast and the 12-segment broadcast, and at the same time determines whether the broadcast is a simultaneous broadcast. Is determined (step S902).

  When the analysis of the broadcast timing difference is completed, the broadcast receiver 40 transmits the broadcast data of the 12-segment broadcast from the buffer to the video, audio, and subtitle decoding units 409 to 411 while delaying the analyzed broadcast timing difference and timing. (Step S903). The broadcast switching control unit 404 monitors the timing for switching the broadcast to 12-segment broadcasting, and instructs the broadcast switching unit 412 to switch the broadcast when the switching timing comes (step S904). The broadcast switching unit 412 switches the 1-segment broadcast data output to the monitor 413 to the 12-segment broadcast data according to the instructed switching timing (step S905).

  By the above procedure, using the broadcast timing difference obtained by the above-described analysis of the broadcast timing difference, by delaying the start of decoding of the 12-segment broadcast, while suppressing the broadcast timing difference, from the viewing state of the 1-segment broadcast, Viewing of 12-segment broadcasting can be started.

  FIG. 10 shows the flow of data from the buffers 51 to 56 of the timing control unit 405 to the decoding units 406 to 411. The timing control unit 405 stores each PES data in the buffers 51 to 56 before decoding, and delays the decoding start time of 12-segment broadcast data by the difference in broadcast timing.

  In this embodiment, each of the buffers 51 to 56 for correcting the broadcast timing difference is provided in the timing control unit 405. However, after decoding each data of 1-segment broadcasting and 12-segment broadcasting, a buffer for timing adjustment is provided. You may prepare. If there is a large difference in the decoding time of 1-segment broadcasting data and 12-segment broadcasting data, and the time difference between the decoding results in a shift in the timing of finally outputting each data to the monitor, video and audio that have been decoded in advance Output data such as subtitles is stored in a buffer, and when it is displayed and played back on an output device, display and playback that suppresses the broadcast timing difference by controlling the output timing based on the aforementioned broadcast timing difference Will be able to.

  The broadcast timing difference may vary depending on the broadcast station and the broadcast form of the program such as live broadcast or recording. Therefore, when a change occurs in a broadcast received at the receiver side or a program being viewed, a new broadcast timing difference may be reexamined so that smooth broadcast switching can be performed after the change. As with the stream, the program is changed by acquiring the title of the program from the EIT (Event Information Table), which is program information data transmitted as broadcast data, and checking it as needed to check whether there is a change.

  However, the analyzed broadcast timing difference data should be stored for a certain period, and if the channel or program for which the broadcast timing difference has already been analyzed is viewed again, the stored broadcast timing difference data should be used. Thus, it is possible to omit the process of checking again. Specifically, the time when the broadcast timing difference is analyzed, the channel number of the program to be analyzed, the program title name, and the data of the broadcast timing difference may be stored as one data set.

  Only when the program for analyzing the broadcast timing difference does not support subtitle broadcasting, the timing difference is analyzed by substituting video and audio data. For example, when video data is used, it is possible to determine whether the video data is in the same scene by calculating and comparing a luminance histogram and a color histogram from video data of 1-segment broadcasting and 12-segment broadcasting.

  The method of determining the correspondence status of subtitle broadcasting is that the subtitle data is included in the broadcast data for a certain period of time, or the title of the EIT (Event Information Table) data including the program information, the detailed program description, etc. Since the item includes information indicating whether or not captions are supported, it is possible to determine the caption support status by checking the information.

(Embodiment 2)
Next, a second embodiment of the broadcast receiver according to the present invention will be described with reference to FIGS. FIG. 11 shows a functional block configuration of the broadcast receiver 110 in the present embodiment. The broadcast receiver 110 includes a receiving unit 1101, a 1-segment TS decoding unit 1102, a 12-segment TS decoding unit 1103, a broadcast switching control unit 1104, a timing control unit 1105, a 1-segment video decoding unit 1106, and a 1-segment audio decoding. Unit 1107, 1-segment subtitle decoding unit 1108, 12-segment video decoding unit 1109, 12-segment audio decoding unit 1110, 12-segment subtitle decoding unit 1111, broadcast switching unit 1112, and monitor 1113.

  The receiving unit 1101 demodulates the broadcast signal received via the antenna into TS data. The receiving unit 1101 outputs the 1-segment broadcasting TS decoder to the 1-segment TS decoding unit 1102. The receiving unit 1101 outputs 12-segment broadcasting TS data to the 12-segment TS decoding unit 1103. In addition, receiving section 1101 outputs the above-mentioned broadcast reception level information to broadcast switching control section 1104.

  The 1-segment TS decoding unit 1102 demultiplexes 1-segment broadcasting TS data, and outputs PES data of moving images, audio, and captions to the timing control unit 1105. On the other hand, the 12-segment TS decoding unit 1103 demultiplexes the 12-segment broadcasting TS data, and outputs each PES data to the timing control unit 1105 in the same manner as the 1-segment TS decoder unit 1102. Also, each TS decoding section 1102 and 1103 outputs the PTS of the caption data included in the broadcast data for a certain period to the broadcast switching control section 1104.

  The broadcast switching control unit 1104 monitors the broadcast reception level information received from the receiving unit 1101, selects a broadcast to be received from the 1-segment broadcast and the 12-segment broadcast, and performs broadcast switching using the selected broadcast information as switching information. Output to the unit 1112. Also, the broadcast switching control unit 1104 analyzes the time difference between the broadcast timings of the 1-segment broadcast and the 12-segment broadcast. Other configurations are the same as those in the first embodiment.

  FIG. 12 shows functional blocks of the broadcast switching control unit 1104 of this embodiment. The broadcast switching control unit 1104 includes a caption data analysis unit 1201, a reception status analysis unit 1202, and a switching determination unit 1203. The subtitle PES data PTS is received by the subtitle data analysis unit 1201. Then, the caption data analysis unit 1201 analyzes the broadcast timing difference.

  A method for analyzing a broadcast timing difference in the caption data analysis unit 1201 will be described. In the second embodiment, a plurality of PTSs described in subtitle PES data of 1-segment broadcasting and 12-segment broadcasting are simultaneously recorded, and the interval pattern of time information described in each PTS is 1-segment broadcasting and 12-segment broadcasting. A method of checking a broadcast timing difference by matching a portion similar to the broadcast and analyzing a presentation time difference indicating a PTS time difference is used.

  Hereinafter, an analysis method by pattern matching of subtitle PTS (PTS of subtitle PES data) will be described. FIG. 13 shows an example in which subtitle PES data of 12-segment broadcasting and 1-segment broadcasting is stored for the same time and mapped on time according to time information indicated by subtitle PTS. The subtitles PTS described in the 12-segment broadcasting PES are a1, a2, a3,... In order from the earliest, and the subtitle PTS of the 1-segment broadcasting is similarly b1, b2, b3,. Also, the interval between the subtitles PTS is Δa1 (the interval between a1 and a2), Δa2 (the interval between a2 and a3), and so on.

  FIG. 14 is a flowchart showing an operation of a timing difference analysis process for performing PTS pattern matching using the subtitle PTS mapping data shown in FIG. First, the caption data analysis unit 1201 stores a specific number (M) of subtitles PTS of 12-segment broadcasting and 1-segment broadcasting, respectively (step S1401). As described above, subtitle PTS for 12-segment broadcasting is a1 to aM, and subtitle PTS for 1-segment broadcasting is b1 to bM.

  Next, the caption data analysis unit 1201 calculates the intervals Δa1 to Δa (M−1) and Δb1 to Δb (M−1) between the caption PTSs (step S1402).

  The caption data analysis unit 1201 then performs pattern matching between the 1-segment broadcast and the 12-segment broadcast on the calculated caption PTS (step S1403). As an example of pattern matching, first, the interval data Δb1 to ΔbM of 1 segment broadcasting is searched for the same value as Δa1, and if the same interval data is found, the next interval data of each matched data is found. Are determined to be the same. At this time, if it is determined that the values are the same, the next interval data is further compared to determine whether or not they are the same. If the intervals are different, a search is made again for those that are equal to Δa1, and a combination that can be repeatedly and continuously matched is found.

  As the number of the same value continuously increases, more accurate matching can be obtained. However, the amount of comparison data increases, and it is necessary to store a large amount of time for calculation and data to be compared. In the above-mentioned matching, it is determined whether the subtitle PTS interval of 12-segment broadcasting and 1-segment broadcasting is the same value, but these intervals are smaller than several hundred milliseconds to several seconds assumed by the broadcast timing difference. Since an error is included, matching is determined including the error.

  If the same scene is found as a result of pattern matching (step S1404; Yes), the caption data analysis unit 1201 calculates the difference between PTSs that match between the 1-segment broadcast and the 12-segment broadcast, and obtains the presentation time difference. (Step S1405). On the other hand, if pattern matching is not established and the same scene is not found (step S1404; No), it is determined that the 1-segment broadcast program is not a 12-segment broadcast simultaneous broadcast (step S1406).

  In the second embodiment, the broadcast timing difference is analyzed by pattern matching of the caption PTS. In the broadcast timing difference analysis method described in the first embodiment, the presentation time difference is analyzed by comparing the PTSs of the caption PES data in which the caption text is the same in the 1-segment broadcast and the 12-segment broadcast. For this reason, subtitle PES data is decoded to obtain subtitle text data. However, in the second embodiment, subtitle PES data need not be decoded, and the presentation time difference is analyzed by using the PTS included in the PES header. can do.

  Also in the present embodiment, the reference time difference analysis method described in the first embodiment can be used, and the reference time difference analyzed by the same method and the presentation time difference analysis method described in the present embodiment are used. By using the obtained presentation time differences and totaling them, it is possible to analyze the broadcast timing difference between the 12-segment broadcast and the 1-segment broadcast.

  Then, by using the analyzed broadcast timing difference, broadcast switching can be performed while suppressing the difference between 1-segment broadcast and 12-segment broadcast. This switching method can be realized by applying the method described as the operation example of the broadcast switching unit 412 in the first embodiment in the same manner in the broadcast switching unit 1112 of the second embodiment.

  In the above embodiments, the program executed by the CPU has been described as being stored in the ROM in advance. This program may be stored in a predetermined storage area or the like via an external storage medium or a communication network.

DESCRIPTION OF SYMBOLS 1 ... Video encoding part, 2 ... Audio encoding part, 3 ... Subtitle encoding part, 4 ... TS encoding part, 10 ... Transmitter, 21 ... PES data, 22 ... PTS, 23 ... PES header, 24 ... PES packet, 25 ... TS data, 26 ... TS header, 27 ... PCR, 30 ... receiver, 301 ... receiving unit, 302 ... TS decoding unit, 303 ... buffer control unit, 304 ... video buffer, 305 ... audio buffer, 306 ... subtitle buffer, 307 ... Timing control unit, 308 ... Video decoding unit, 309 ... Audio decoding unit, 310 ... Subtitle decoding unit, 311 ... STC, 40 ... Broadcast receiver, 401 ... Receiving unit, 402 ... TS decoding unit for 1 segment, 403 ... 12 TS decoding unit for seg, 404 ... broadcast switching control unit, 405 ... timing control unit, 406 ... video decoding unit for 1 seg 407 ... 1-segment audio decoding section, 408 ... 1-segment subtitle decoding section, 409 ... 12-segment video decoding section, 410 ... 12-segment audio decoding section, 411 ... 12-segment subtitle decoding section, 412 ... broadcast switching section 413 ... Monitor, 51 ... 1 segment video buffer, 52 ... 1 segment audio buffer, 53 ... 1 segment subtitle buffer, 54 ... 12 segment video buffer, 55 ... 12 segment audio buffer, 56 ... 12 segment subtitle buffer, 57 ... Buffer control unit 61 ... Subtitle data analysis unit 62 ... Reception status analysis unit 63 ... Switch determination unit 110 ... Broadcast receiver 1101 ... Reception unit 1102 ... 1 segment TS decoding unit 1103 ... 12 segment TS Decoding unit, 1104 ... broadcast switching control unit, 1105 ... timing control unit, 1106 ... 1-segment video decoding unit, 1107 ... 1-segment Audio decoding unit, 1108 ... 1-segment subtitle decoding unit, 1109 ... 12-segment video decoding unit, 1110 ... 12-segment audio decoding unit, 1111 ... 12-segment subtitle decoding unit, 1112 ... broadcast switching unit, 1113 ... monitor, 1201 ... Subtitle data analysis unit 1202 ... Reception status analysis unit 1203 ... Switch determination unit

Claims (11)

Broadcast receiving means for receiving first broadcast data and second broadcast data from a broadcast wave;
Caption data extraction means for extracting caption data corresponding to each broadcast data from the first broadcast data and the second broadcast data received by the broadcast receiving means;
By comparing the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extracting means and the second subtitle data corresponding to the second broadcast data, the first subtitle data is extracted. Subtitle data analysis means for measuring a time difference between broadcast data and the second broadcast data;
Equipped with a,
The caption data analysis means includes
By searching for the same scene using text data included in the first subtitle data and the second subtitle data, and comparing the time when each subtitle data of the searched scene is presented, Measuring the time difference between the broadcast data and the second broadcast data;
In the text data included in the first subtitle data and the second subtitle data, it is determined whether or not they are the same scene by calculating a ratio including the same characters.
Digital data receiver, wherein the this. Broadcast receiving means for receiving first broadcast data and second broadcast data from a broadcast wave;
Caption data extraction means for extracting caption data corresponding to each broadcast data from the first broadcast data and the second broadcast data received by the broadcast receiving means;
By comparing the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extracting means and the second subtitle data corresponding to the second broadcast data, the first subtitle data is extracted. Subtitle data analysis means for measuring a time difference between broadcast data and the second broadcast data;
With
The subtitle data analyzing means searches for a similar pattern portion in which a time interval pattern for presenting the first subtitle data and a time interval pattern for presenting the second subtitle data are similar to each other, by calculating the time difference of the similar pattern portion, wherein the to Lud digital data receivers to measure the time difference between the first broadcast data and the second broadcast data. Broadcast receiving means for receiving first broadcast data and second broadcast data from a broadcast wave;
Caption data extraction means for extracting caption data corresponding to each broadcast data from the first broadcast data and the second broadcast data received by the broadcast receiving means;
By comparing the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extracting means and the second subtitle data corresponding to the second broadcast data, the first subtitle data is extracted. Subtitle data analysis means for measuring a time difference between broadcast data and the second broadcast data;
With
The subtitle data analysis means, the broadcast receiving means of the first broadcast data, wherein the to Lud digital data receivers to measure the time difference between the second broadcast data when the program is changed to receive . First decoding means for decoding the first broadcast data;
Second decoding means for decoding the second broadcast data;
Timing control means for controlling the timing of starting decoding of each of the broadcast data;
A simulcast broadcast discriminating means for discriminating whether or not the first broadcast data and the second broadcast data are simulcast broadcast data;
The timing control means, when it is determined that the first broadcast data and the second broadcast data are the broadcast data of the simulcast, the first broadcast data measured by the caption data analysis means The digital data receiver according to any one of claims 1 to 3 , wherein the decoding start timing of each broadcast data is controlled based on a time difference from the second broadcast data. The timing control means accumulates the data amount corresponding to the time difference in the buffer for the broadcast data with the earlier reception timing out of the first broadcast data and the second broadcast data, and sets the decoding start timing. The digital data receiver according to claim 4 , wherein the digital data receiver is delayed. The simulcast discrimination unit compares the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extraction unit and the second subtitle data corresponding to the second broadcast data. it allows digital data receiver according to claim 4 or 5, characterized in that discrimination between broadcasting data simulcast. Broadcast receiving means for receiving first broadcast data and second broadcast data from a broadcast wave;
Caption data extraction means for extracting caption data corresponding to each broadcast data from the first broadcast data and the second broadcast data received by the broadcast receiving means;
By comparing the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extracting means and the second subtitle data corresponding to the second broadcast data, the first subtitle data is extracted. Subtitle data analysis means for measuring a time difference between broadcast data and the second broadcast data;
When the caption data cannot be extracted by the caption data extraction means, the first broadcast data and the second broadcast data are based on video data or audio data included in the first broadcast data and the second broadcast data. a time difference measuring means for measuring a time difference between the broadcast data,
Features and to Lud digital data receiver that comprises a. Computer
Broadcast receiving means for receiving first broadcast data and second broadcast data from a broadcast wave;
Caption data extraction means for extracting caption data corresponding to each broadcast data from the first broadcast data and the second broadcast data received by the broadcast receiving means;
By comparing the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extracting means and the second subtitle data corresponding to the second broadcast data, the first subtitle data is extracted. Subtitle data analysis means for measuring a time difference between broadcast data and the second broadcast data;
To function as,
The caption data analysis means includes
By searching for the same scene using text data included in the first subtitle data and the second subtitle data, and comparing the time when each subtitle data of the searched scene is presented, Measuring the time difference between the broadcast data and the second broadcast data;
In the text data included in the first subtitle data and the second subtitle data, it is determined whether or not they are the same scene by calculating a ratio including the same characters.
Program which is characterized a call.   Computer
  Broadcast receiving means for receiving first broadcast data and second broadcast data from a broadcast wave;
  Caption data extraction means for extracting caption data corresponding to each broadcast data from the first broadcast data and the second broadcast data received by the broadcast receiving means;
  By comparing the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extracting means and the second subtitle data corresponding to the second broadcast data, the first subtitle data is extracted. Subtitle data analysis means for measuring a time difference between broadcast data and the second broadcast data;
  Function as
  The subtitle data analyzing means searches for a similar pattern portion in which a time interval pattern for presenting the first subtitle data and a time interval pattern for presenting the second subtitle data are similar to each other, The time difference between the first broadcast data and the second broadcast data is measured by calculating the time difference between the similar pattern portions.
  A program characterized by that.   Computer
  Broadcast receiving means for receiving first broadcast data and second broadcast data from a broadcast wave;
  Caption data extraction means for extracting caption data corresponding to each broadcast data from the first broadcast data and the second broadcast data received by the broadcast receiving means;
  By comparing the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extracting means and the second subtitle data corresponding to the second broadcast data, the first subtitle data is extracted. Subtitle data analysis means for measuring a time difference between broadcast data and the second broadcast data;
  Function as
  The caption data analyzing means measures a time difference between the first broadcast data and the second broadcast data when a program received by the broadcast receiving means changes.
  A program characterized by that.   Computer
  Broadcast receiving means for receiving first broadcast data and second broadcast data from a broadcast wave;
  Caption data extraction means for extracting caption data corresponding to each broadcast data from the first broadcast data and the second broadcast data received by the broadcast receiving means;
  By comparing the first subtitle data corresponding to the first broadcast data extracted by the subtitle data extracting means and the second subtitle data corresponding to the second broadcast data, the first subtitle data is extracted. Subtitle data analysis means for measuring a time difference between broadcast data and the second broadcast data;
  When the caption data cannot be extracted by the caption data extraction means, the first broadcast data and the second broadcast data are based on video data or audio data included in the first broadcast data and the second broadcast data. Time difference measuring means for measuring the time difference from the broadcast data of
  A program characterized by functioning as

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