JP2007104473A - Digital broadcast input switching apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent or minimize broadcasting stop wave within a CATV network and to repair a fault of a CATV transmission device while providing services. <P>SOLUTION: By monitoring PAT or PMT of a TS received from a TS transmission device 20, a TS transmission device 21 is used for input and output is provided from an output 13 when any fault occurs in the TS transmission device 20. Thus, a CATV retransmission system can be easily maintained without service stop for a CATV subscriber side. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a digital broadcast input switching device and a control method in a program distribution system, and in particular, when a digital broadcast is retransmitted to a program distribution network such as CATV, an alternative associated with a stop of the digital broadcast program transmission device The present invention relates to a broadcast switching method and a control method.

  Currently, in order to retransmit broadcast content to the CATV network, a CATV company uses a device for performing retransmission (hereinafter referred to as a CATV transmission device), but the broadcast content output from a plurality of CATV transmission devices. Broadcast content switching devices are used to switch between the two.

  The broadcast content switching device immediately switches the broadcast and shortens the stop time when the service is switched at the CATV company, or when the signal from the CATV transmitting device being output is stopped for some reason. Has the role of

  The broadcast content switching device performs switching based on the presence / absence of a signal and does not perform switching based on the content of the broadcast content. Therefore, if the basic signal of the broadcast content is formed, the switching is not performed (for example, , See Patent Document 1).

  Usually, for recognition of a video signal, the signal is determined based on the presence / absence of a video synchronization signal. Therefore, if there is a synchronization signal, it is determined that the broadcast is not stopped in terms of hardware.

  However, when the broadcast content transmitted from the CATV company is stopped for some reason, only the synchronization signal on the transmission side is transmitted, and the broadcast content is retransmitted in a state where nothing is superimposed. Will occur.

  Therefore, in order to confirm the content of the broadcast content, it is necessary to check the video by viewing through a terminal device, and it is difficult to automatically detect a failure due to a failure of the CATV transmission device and restore the failure. .

Furthermore, it is important for CATV companies to provide continuous service to CATV subscribers. Under such circumstances, it is necessary to prevent broadcast breakage due to a failure of the CATV transmission apparatus or to shorten the broadcast break time.
JP 2001-285666 A

  When the CATV retransmission system is taken as an example to solve the problem, the signal output from the CATV transmission apparatus is a signal transmitted from the CATV transmission apparatus even when a failure occurs in the CATV transmission apparatus, which is a program retransmission apparatus, in the conventional configuration. If the basic signal of the broadcast content is formed, it is not possible to switch to the broadcast content from the CATV transmission device that is operating normally regardless of the viewing state.

  In the above situation, since it is necessary to manually switch by the contact from the CATV viewer or the monitor, it may take a long time until the cause is resolved after the failure occurs and the service is resumed. .

  This time becomes the broadcast stop time, and in order to provide a continuous service as a CATV company, it is necessary to shorten the broadcast stop time.

  In order to solve the above problems, the present invention determines whether or not digitized broadcast content is input between the CATV transmitting apparatus and the CATV network, and further includes a PAT and program content constituting program information included in the broadcast content. When the broadcast content is difficult to watch, the program content is confirmed by constantly monitoring the PMT constituting the broadcast, and the broadcast content output from the CATV transmission device is monitored on the CATV subscriber side. Is characterized in that a digital broadcast input switching device for determining that a failure has occurred in the CATV transmission device and switching to the output from the CATV transmission device that normally transmits broadcast content is inserted.

  As a result, it is possible to prevent a broadcast stoppage in the CATV network or to minimize the broadcast stoppage and to repair a failure of the CATV transmission apparatus while providing a service.

  According to the present invention, a CATV company can maintain a CATV transmission apparatus without stopping or minimizing the service for subscribers.

  Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1)
FIG. 1 is an example of a configuration diagram of the present invention according to Embodiment 1 of the present invention.

  The digital broadcast input switching device 30 includes a main input receiving unit 3 that receives a transport stream (hereinafter, TS) input from the main input 1, a sub input receiving unit 4 that receives a TS input from the sub input 2, A PAT extraction unit 5 that extracts a PAT from the TS received by the input reception unit 3, a PAT analysis unit 6 that analyzes the extracted PAT, and a monitoring target that holds service information input from the monitoring target service input 7 via the CPU 8 The service management unit 9 includes a service monitoring unit 10 that monitors an input service, a signal selection unit 11 that selects an input signal, and a signal output unit 12 that outputs the selected signal to an output 13.

  Here, the TS constituting the program input from the main input 1 is received by the main input receiving unit 3.

  The TS received by the main input receiving unit 3 is output from the signal output unit 12 to the output 13 via the signal selection unit 11.

  On the other hand, the TS received by the main input receiving unit 3 is also sent to the PAT extracting unit 5 to reconstruct the PAT information.

  The reason why the PAT information is reconstructed from the TS sent to the PAT extraction unit 5 is to facilitate the extraction of information necessary for monitoring the input service.

  From the PAT information reconstructed by the PAT extraction unit 5, the service number described in the PAT is extracted by the PAT analysis unit 6.

  Also, information on the service to be monitored input from the monitoring target service input 7 is held in the monitoring target service management unit 9 via the CPU 8.

  At this time, the service monitoring unit 10 compares the service held by the monitoring target service management unit 9 with the service number extracted from the PAT by the PAT analysis unit 6, and the monitoring target service number is described in the PAT. Determine if there is.

  For example, it is assumed that the monitored service input from the monitored service input 7 is the “100” channel. Whether the TS input from the main input 1 is sent from the main input receiving unit 3 to the PAT extracting unit 5 and the PAT analyzing unit 6 and whether the monitored service “100” channel is included in the input service is determined. It is constantly monitored.

  When the service monitoring unit 10 determines that the service number to be monitored is not described in the PAT, the sub-input receiving unit 4 receives the signal from the TS received by the main input receiving unit 3 to the signal selection unit 11. By instructing the TS to be switched, the TS received by the sub-input receiving unit 4 is transferred to the signal output unit 12 via the signal selection unit 11 and output from the output 13.

  With the above control, input switching control can be performed, and when a failure occurs in the TS transmission device 20 with respect to the main input 1, the TS can be automatically switched to the TS output from the TS transmission device 21.

(Embodiment 2)
FIG. 2 is an example of a configuration diagram of the present invention in Embodiment 2 of the present invention.

  In addition to the configuration shown in FIG. 1, a timer 14 to which the PAT analysis unit 6 refers is added.

  Here, an example will be described in which the PAT analysis unit 6 determines that the PAT is not included in the TS received by the main input reception unit 3.

  The PAT analysis unit 6 acquires and holds the time when the PAT information reconstructed by the PAT extraction unit 5 is sent to the PAT analysis unit 6 from the timer 14 as the previous PAT reception time.

  Then, the PAT analysis unit 6 monitors the time of the PAT information sent next from the PAT extraction unit 5 with reference to the timer 14.

  When the next PAT information is sent from the PAT extraction unit 5, the PAT analysis unit 6 refers to the timer 14 to update the previous PAT reception time to the time acquired from the timer 14 and simultaneously receives the PAT information. Measure the average time interval. The average time interval is output to the outside via the monitored service input 7.

  Here, when all of the TS or a part of the TS including the PAT is not transmitted from the TS transmission device 20, the PAT analysis unit 6 cannot receive the PAT information from the PAT extraction unit 5.

  The PAT analysis unit 6 refers to the timer 14 and notifies the service monitoring unit 10 of the PAT information non-reception state when the PAT information is not received beyond a certain interval.

  When the service monitoring unit 10 receives the PAT information non-reception state from the PAT analysis unit 6, the service monitoring unit 10 instructs the signal selection unit 11 to transfer the TS received by the auxiliary input reception unit 4 to the signal output unit 12. TS can be switched automatically.

  The time for the PAT analysis unit 6 to determine that the PAT information has not been received is set from the outside via the same route as the monitored service input 7 and is held by the PAT analysis unit 6. By setting from the outside, it is possible to monitor at an arbitrary time interval. Further, since the PAT transmission interval is determined to be 100 msec according to the ARIB standard, it is possible to set the monitoring time for the PAT non-reception state by setting the integral multiple of the time.

(Embodiment 3)
FIG. 3 is an example of a configuration diagram of the present invention in Embodiment 3 of the present invention.

  In addition to the configuration of FIG. 2, a system in which the main input receiving unit 3 refers to the timer 14 and a system in which the main input receiving unit 3 notifies the service monitoring unit 10 of the TS unreceived state are added.

  Here, an example will be described in which the main input receiving unit 3 detects the synchronization byte of the TS and measures the reception time interval to determine that the TS is no longer received.

  The main input receiving unit 3 monitors the synchronization byte of the TS input to the main input 1.

  FIG. 6 is an example of a diagram showing a transmitted TS packet.

  The TS synchronization byte (0x47) indicates the beginning of a TS packet transmitted in units of 188 bytes. Therefore, it is possible to determine that a TS packet is input by constantly monitoring the synchronization byte.

  The TS that is the subject of the present invention has a unit of 188 bytes or 204 bytes of data, and the head of the data string has a format in which 1 byte of data called a synchronization byte is inserted. Furthermore, a data string not having the above format does not make sense as a TS. Therefore, data to be received after a certain TS transmission time can be a synchronization byte. Therefore, it can be determined that there is reception from the main input by monitoring the synchronization byte.

  When the main input receiving unit 3 receives this synchronization byte, it refers to the timer 14 and acquires and holds it as the previous TS reception time.

  Next, when a TS is received, the timer 14 is referred to update the previous TS reception time to the time acquired from the timer 14, and at the same time, the average time interval of TS information reception intervals is measured.

  The main input receiving unit 3 refers to the timer 14 and notifies the service monitoring unit 10 of the TS non-reception state when the TS is not received exceeding the integral multiple of the average time interval.

  A value that is an integral multiple of the TS information reception average time interval for the main input receiving unit 3 to determine that TS information has not been received is set from the outside via the same route as the monitored service input 7, and the main input receiving unit 3 Saved at 3. As a result, monitoring can be performed at arbitrary time intervals.

  Here, as a condition for determining that TS information is not received, the integer multiple of the TS information reception average time interval is taken into account when the transmission interval is extended for some reason in the transmission side device. It is an integral multiple and has a margin.

  By making the transmission speed of the TS constant, the time for the main input receiving unit 3 to receive one TS is also constant.

  Next, the time obtained by subtracting the TS transmission time from the time interval between a certain TS and the next TS to be received fluctuates depending on the contents transmitted by the TS and the accuracy of the device that outputs the TS.

  Therefore, by obtaining the shake as an average value, and further multiplying the obtained average value by an integer, the present invention prevents erroneous determination of TS information not received due to temporal fluctuation occurring between TSs. be able to.

  When receiving the TS non-receiving state from the main input receiving unit 3, the service monitoring unit 10 instructs the signal selecting unit 11 to transfer the TS received by the sub input receiving unit 4 to the signal output unit 12, TS can be switched automatically.

(Embodiment 4)
FIG. 4 is an example of a configuration diagram of the present invention in Embodiment 4 of the present invention.

  In addition to the configuration of FIG. 3, a PMT extraction unit 16 that extracts a PMT from a TS received by the main input reception unit 3, a PMT analysis unit 15 for analyzing the PMT information extracted by the PMT extraction unit 16, and A monitoring target component management unit 17 that holds monitoring target component information set from outside via the monitoring target service input 7 and the CPU 8 is added.

  The TS sent from the TS sending device 20 is received by the main input receiving unit 3.

  The TS received by the main input receiving unit 3 is transferred to the PMT extracting unit 16, and PMT information is extracted.

  From the PMT information extracted by the PMT extraction unit 16, the PMT analysis unit 15 extracts component information constituting the program transmitted by the TS transmission device 20.

  FIG. 7 is an example showing a PMT structure.

  The component information in the PMT includes information for identifying a transmission TS in units such as video, audio, and data constituting a program, contents transmitted in the TS, and information used on the receiving device side. Information is recorded.

  Therefore, by monitoring the component information in the PMT, it is possible to identify the video, audio, presence / absence of data, and transmission TS constituting the program.

  The service monitoring unit 10 refers to the component information extracted by the PMT analysis unit 15 and the monitoring target component information held in the monitoring target component management unit 17, and the monitoring target component information is not described in the PMT. Is detected, and the signal selection unit 11 is instructed to switch to the TS received by the sub-input reception unit 4.

  With the above control, input switching control can be performed, and when a failure occurs in the TS transmission device 20 with respect to the main input 1, the TS can be automatically switched to the TS output from the TS transmission device 21.

(Embodiment 5)
FIG. 5 is an example of a configuration diagram of the present invention in Embodiment 5 of the present invention.

  In addition to the configuration of FIG. 4, a clock management unit 18 that manages the internal clock and a switching time management unit 19 that holds a switching time from the main input to the sub input are added.

  Information managed by the switching time management unit 19 is set from the outside via the monitored service input 7 and the CPU 8.

  The clock management unit 18 constantly monitors the internal clock, and when the switching time held by the switching time management unit 19 matches the time of the internal clock, the service monitoring unit 10 switches from the primary input 1 to the secondary input 2. Instruct.

  Instructed to switch, the service monitoring unit 10 instructs the signal selection unit 11 to switch from the TS received by the main input receiving unit 3 to the TS received by the sub input receiving unit 4, whereby the sub input receiving unit The TS received at 4 is transferred to the signal output unit 12 via the signal selection unit 11 and output from the output 13.

  The above control makes it possible to control the time of input switching, and the TS sending device 21 outputs when the input is switched outside the operation time for the main input 1 for periodic maintenance of the TS sending device 20 or the like. Can be automatically switched at the time specified for the TS.

(Embodiment 6)
In FIG. 1 to FIG. 4, the TS input is two inputs of the primary input 1 and the secondary input 2. However, the order of switching to each secondary input is further provided by giving a plurality of secondary inputs without limiting the number of TS inputs. It is determined that there is no TS input because the monitored service number is not described in the main input PAT, or the monitored component information is not described in the PMT. In the case where the TS input is made, the presence or absence of the TS input is determined according to the priority order from the plurality of sub inputs, and the TS input is switched to the sub input.

  As a result, a stream to be output from the plurality of input TSs to the output 13 can be selected.

  Here, the priority order can be set from the outside via the monitored service input 7 and the CPU 8.

(Embodiment 7)
In the first to sixth embodiments, after the TS input is switched from the primary input 1 to the secondary input 2, even if the TS input of the primary input 1 is restored, the secondary input 2 is not restored to the primary input 1. When the TS input to the main input 1 is restored, the main input 1 is restored regardless of the TS input state of the sub input 2.

  Thereby, when TS input is normally performed from the input 1, the input 1 can be substantially fixed to the main input device.

  Here, the restart of the TS input of the main input 1 is determined by the service monitoring unit 10.

(Embodiment 8)
In the seventh embodiment, after the TS input is switched from the main input 1 to the sub input 2, when the TS input of the main input 1 is restored, the sub input 2 is restored to the main input 1. By setting, the signal input from the sub input is continued without returning to the main input.

  Here, the non-return setting to the main input can be set from the outside via the monitored service input 7 and the CPU 8.

  By fixing the switched sub-input signal as it is, it is possible to prevent frequent occurrence of wave-stopping for a subscriber who is watching, although for a short time.

  In a CATV company, it is useful for maintenance of a CATV transmission apparatus that does not cause a service stop. In addition, even when the CATV transmission device breaks down, it is possible to switch to another CATV transmission device in a short time, so that the service stop time for the subscriber can be shortened.

  Furthermore, it can be used as a simple transport stream switching device.

The block diagram which shows the structure of the digital broadcast input switching apparatus which concerns on Embodiment 1 of this invention. The block diagram which shows the structure of the digital broadcast input switching apparatus which concerns on Embodiment 2 of this invention. The block diagram which shows the structure of the digital broadcast input switching apparatus which concerns on Embodiment 3 of this invention. The block diagram which shows the structure of the digital broadcast input switching apparatus which concerns on Embodiment 4 of this invention. The block diagram which shows the structure of the digital broadcast input switching apparatus which concerns on Embodiment 5 of this invention. Diagram showing an example of TS packet Diagram showing PMT structure

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main input 2 Sub input 3 Main input receiving part 4 Sub input receiving part 5 PAT extraction part 6 PAT analysis part 7 Monitoring object service input 8 CPU
DESCRIPTION OF SYMBOLS 9 Monitoring object service management part 10 Service monitoring part 11 Signal selection part 12 Signal output part 13 Output 14 Timer 15 PMT analysis part 16 PMT extraction part 17 Monitoring object component management part 18 Clock management part 19 Switching time management part 20 Transport stream transmission Device 21 Transport stream sending device

Claims (8)

An input monitoring device that constantly monitors the presence or absence of a digital broadcast signal is a main digital broadcast signal receiving means for receiving a digital broadcast signal from a digital broadcast signal transmission system;
Sub-digital broadcast signal receiving means for receiving a digital broadcast signal transmitted from a route different from the digital broadcast signal transmission system;
PAT extraction means for extracting PAT from the digital broadcast signal received by the main digital broadcast signal receiving means;
PAT analysis means for analyzing the contents of the PAT extracted by the PAT extraction means;
A monitored service management means for maintaining a monitored service designated externally inside the device;
Service monitoring means for determining the presence or absence of a service from the output of the PAT analysis means and the monitoring target service held by the monitoring target service management means;
A digital broadcast signal selecting means for selecting a digital broadcast signal output from the main digital broadcast receiving means and the sub digital broadcast receiving means according to the result of the service monitoring means;
A digital broadcast signal output means for transmitting the digital broadcast signal output from the digital broadcast signal selection means to the outside;
The service monitoring means detects that the monitored service is no longer described in the PAT received by the main digital broadcast signal receiving means, and selects the digital broadcast signal received by the sub digital broadcast signal receiving means. A digital broadcast input switching device characterized by outputting a signal to the digital broadcast signal selection means. The digital broadcast input switching device measures a time interval for receiving a PAT in the PAT extraction unit, and receives the PAT from the sub digital broadcast signal receiving unit when a PAT is not received exceeding a certain interval equal to or greater than an average reception interval. 2. The digital broadcast input switching device according to claim 1, wherein a digital broadcast signal is output from the digital broadcast transmission means. The digital broadcast input switching device detects the synchronization byte of the received transport stream packet and measures the reception time interval in the main digital broadcast signal receiving means, and the transport stream packet exceeds an integral multiple of the average reception interval. 3. The digital broadcast input switching device according to claim 1, wherein when the signal is not received, the digital broadcast signal received from the sub digital broadcast signal receiving means is output from the digital broadcast sending means. The digital broadcast input switching device comprises a PMT extraction means for extracting a PMT received by the main digital broadcast signal receiving means, and a PMT analysis means for analyzing the contents of the PMT extracted by the PMT extraction means. 2. The apparatus according to claim 1, wherein it is detected that information relating to a component constituting a service is not described in the PMT, and a digital broadcast signal received from the sub-digital broadcast signal receiving means is output from the digital broadcast sending means. The digital broadcast input switching device according to claim 3. The digital broadcast input switching device includes a switching time holding means for holding a switching time designated from the outside and an internal clock, and the digital broadcast received from the sub digital broadcasting signal means when the designated switching time is reached. 5. The digital broadcast input switching device according to claim 1, wherein a broadcast signal is output from the digital broadcast transmission means. The digital broadcast input switching device comprises a plurality of sub-digital broadcast signal receiving means having priorities, and when the main digital broadcast signal receiving means determines that reception of the signal has been interrupted, 2. A broadcast signal reception presence / absence determination is performed, a sub digital broadcast signal receiving means receiving a digital broadcast signal is selected, and the selected digital broadcast signal is output from the digital broadcast sending means. The digital broadcast input switching device according to claim 5. The digital broadcast input switching device receives the digital broadcast signal received from the main digital broadcast signal receiving unit when it is determined that the reception of the digital broadcast signal at the main digital broadcast signal receiving unit has stopped receiving signals. 7. The digital broadcast input switching device according to claim 1, wherein the digital broadcast transmission means outputs the signal. The digital broadcast input switching device is configured such that when the main digital broadcast signal receiving unit stops receiving a signal and the digital broadcast signal received from the sub digital broadcast signal receiving unit is output from the digital broadcast sending unit, Comprising means for externally designating that the digital broadcast signal received from the main digital broadcast signal input means is not output from the digital broadcast sending means even if it is determined that signal reception has been resumed by the signal receiving means; 8. The digital broadcast signal received from the main digital broadcast signal input means is not output from the digital broadcast sending means when signal reception is resumed by the main digital broadcast signal receiving means. Digital broadcast input switching device.

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