JP6430869B2 - Broadcast receiving apparatus and output control method - Google Patents

Description

  The present invention relates to a broadcast receiving apparatus and an output control method, and in particular, broadcast reception adapted to selectively switch between a first standard broadcast and a second standard broadcast delayed from the first standard broadcast. It is suitable for use in an apparatus and an output control method.

  Conventionally, two broadcasts (for example, DAB (Digital Audio Broadcast) broadcast and IP (Internet Protocol) broadcast) having the same contents but different standards can be received, and these two broadcasts can be selectively switched and output. A broadcast receiving apparatus made in the above has been devised. Thereby, for example, when the reception environment of one broadcast is deteriorated, the user can continue to listen to the same broadcast by switching to the other broadcast and outputting.

  However, there may be a time difference between two broadcasts received by the broadcast receiving apparatus. For example, in a broadcast receiving apparatus that can selectively switch between DAB broadcast and IP broadcast, the IP broadcast is transmitted from the broadcast station to the broadcast receiving apparatus via a provider, an Internet server, or the like. For this reason, it is known that there is a time difference between DAB broadcast and IP broadcast received by the broadcast receiving apparatus, that is, reception of IP broadcast is delayed from reception of DAB broadcast.

  Therefore, conventionally, a technology has been devised that enables seamless switching between two broadcasts by eliminating the time difference between the two broadcasts and synchronizing the output timings of the two broadcasts. ing.

  For example, in Patent Document 1 below, in a duplex configuration IP broadcast transmission system including a 1-system IP transmission server and a 2-system IP transmission server, the 1-system and 2-system are regularly transmitted to TS (Transport Stream). A time stamp is added to the TS signal, and a difference value between a PCR (Program Clock Reference) code included in the TS and the time stamp is detected, and the TS signal is generated based on the difference value detected in each of the first and second systems. On the other hand, a technique for performing synchronization processing is disclosed. Thereby, since IP packets are synchronously input from the 1-system IP transmission server and the 2-system IP transmission server to the switch, it is possible to switch the video smoothly.

JP 2008-227599 A

  Here, conventionally, as a method for obtaining a time difference between two broadcasts in order to synchronize the output timings of the two broadcasts, the broadcast data of the two broadcasts are respectively stored in a buffer, and one broadcast data is converted into the other. A method is used in which the same data as the other broadcast data is specified and the time difference between the reception timing of the same data specified from one broadcast data and the reception timing of the other broadcast data is obtained. However, this method has a problem that it takes a lot of time to calculate the time difference.

  FIG. 11 is a diagram illustrating an example of processing timing by a conventional broadcast receiving apparatus. Here, a conventional broadcast receiving apparatus capable of switching output audio between DAB broadcast and IP broadcast will be described as an example. Also, an example will be described in which audio data having the same content is broadcast as “1”, “2”, “3”, “4”,... In both DAB broadcasting and IP broadcasting. Here, one frame of audio data is schematically shown assuming broadcast data for a predetermined time (for example, 1 second).

  As shown in FIG. 11, the DAB broadcast audio data and the IP broadcast audio data have the same contents, but the IP broadcast is transmitted from the broadcast station to the broadcast receiving device via a provider, an Internet server, or the like. Therefore, it is received later than the DAB broadcast. In the example shown in FIG. 11, the IP broadcast is delayed by two frames of audio data than the DAB broadcast.

  Therefore, in the example shown in FIG. 11, the output timing of the DAB broadcast audio data is performed by performing a delay process on the DAB broadcast audio data so that the switching from the DAB broadcast audio output to the IP broadcast audio output is seamless. Are synchronized with the output timing of the audio data of the IP broadcast.

  Specifically, the broadcast receiving apparatus first detects the same data (link point) as the IP broadcast audio data stored in the IP buffer from the DAB broadcast audio data stored in the DAB buffer. At this time, the broadcast receiving device searches for the same data as the IP broadcast audio data in order from the head of the DAB broadcast audio data stored in the DAB buffer.

  For example, in the example shown in FIG. 11, when the power of the broadcast receiving apparatus is turned on (timing t1 in FIG. 11) and DAB broadcast and IP broadcast audio data is received, the received DAB broadcast and IP broadcast audio is received. Data is sequentially stored in the buffer. In the example shown in FIG. 11, the DAB buffer has a capacity for six frames of audio data. The IP buffer has a capacity for one frame of audio data. When the next new data is received when the maximum amount of audio data is stored in each buffer, the oldest data is ejected from the buffer and the next new data is stored in the buffer. The

  In FIG. 11, when the audio data for 6 frames is first stored in the DAB broadcast buffer after the broadcast receiver is turned on (timing t2 in FIG. 11), the DAB buffer and the IP buffer are switched. Indicates the state. At this time, audio data “1” to “6” are stored in the DAB buffer. Also, audio data “4” is stored in the IP buffer.

  As described above, when the maximum amount of audio data is stored in each buffer, the conventional broadcast receiving apparatus firstly stores the audio data “4” stored in the IP buffer and the head stored in the DAB buffer. By comparing the audio data “1”, “2”, “3”, “4” in order from the DAB buffer, the same data as the audio data “4” stored in the IP buffer is detected from the DAB buffer. In other words, in this example, the same DAB broadcast audio data “4” as the IP broadcast audio data “4” is detected by the fourth comparison.

  The conventional broadcast receiving apparatus calculates the time difference between the reception timing of the IP broadcast audio data “4” and the reception timing of the DAB broadcast audio data “4” as the delay time of the IP broadcast. When the audio data “6” of the DAB broadcast is received, the audio data “4” of the IP broadcast is received, which means that the IP broadcast is delayed by two frames of audio data from the DAB broadcast. is there. In the example shown in FIG. 11, since the comparison process is performed four times in this way, the processing time for four frames of audio data (timing t2 to t3 in FIG. 11) before calculating the IP broadcast delay time. Spend.

  Further, the broadcast receiving apparatus time-stretches the DAB broadcast audio data by the required number of frames so that the calculated delay time of the IP broadcast is eliminated (timing t3 to t4 in FIG. 11). Time stretching refers to extending the playback time by lowering the frequency of the playback process. As a result, the conventional broadcast receiving apparatus eliminates the delay time of the IP broadcast, and the DAB broadcast is in a state where the output timing of the DAB broadcast and the output timing of the IP broadcast are synchronized (state after timing t4 in FIG. 11). It is possible to switch from the output of IP to the output of IP broadcast.

  As described above, since the conventional broadcast receiving apparatus requires a lot of time for calculating the delay time for seamlessly switching the output sound, the synchronization timing of the two broadcasts for seamlessly switching the output sound is advanced. The problem of being unable to do so occurred. For this reason, for example, immediately after switching on the power of the broadcast receiving apparatus, when the necessity for switching to IP broadcasting occurs due to the deterioration of the DAB broadcasting reception environment, it is difficult to switch to IP broadcasting. Inevitably, the user had to keep listening to the DAB broadcast output sound.

  In the example shown in FIG. 11, the amount of data stored in the DAB buffer is 6 frames of audio data (6 frames if 1 frame is 1 second), but in reality, more audio data is stored. It may be necessary to store in a DAB buffer. For example, when it is necessary to store audio data for 60 seconds in the DAB buffer, the comparison process cannot be started unless at least 60 seconds elapse, and the number of comparison processes becomes enormous.

  The present invention has been made to solve such a problem, and an object thereof is to make it possible to advance the synchronization timing of two broadcasts for seamlessly switching output audio.

  In order to solve the above problems, in the present invention, by comparing the broadcast data of the first standard stored in the first storage unit and the broadcast data of the second standard stored in the second storage unit, The same data as the broadcast data of the second standard stored in the second storage unit is identified from the broadcast data of the first standard stored in the first storage unit, and the first standard stored in the first storage unit Of the second standard broadcast from the first standard broadcast based on the reception timing of the same data specified from the broadcast data and the reception timing of the second standard broadcast data stored in the second storage unit. By calculating the delay time and performing delay processing on the broadcast data of the first standard according to the calculated delay time, the output timing of the broadcast data of the first standard is changed to the output timing of the broadcast data of the second standard. Broadcast reception synchronized The time difference between the time information given to the broadcast data of the first standard and the time information given to the broadcast data of the second standard is calculated, and according to the calculation of the time difference, Broadcast data stored in a part of the range is determined as comparison target data, and compared with the comparison target data. From the comparison target data, the second standard broadcast data stored in the second storage unit and The same data is specified.

  According to the present invention configured as described above, in the first standard broadcast data stored in the first storage unit, the range of data to be compared is narrowed according to the calculation of the time difference. Therefore, the process of specifying the same data from the first standard broadcast data can be completed earlier. For this reason, according to the present invention, the synchronization timing of two broadcasts for seamless switching of output audio can be advanced.

It is a block diagram which shows the function structural example of the broadcast receiver which concerns on 1st Embodiment of this invention. It is a flowchart which shows an example of the process by the broadcast receiver which concerns on 1st Embodiment of this invention. It is a figure which shows an example of the process timing by the broadcast receiver which concerns on 1st Embodiment of this invention. It is a block diagram which shows the function structural example of the broadcast receiver which concerns on 2nd Embodiment of this invention. It is a flowchart which shows an example of the process by the broadcast receiver which concerns on 2nd Embodiment of this invention. It is a figure which shows an example of the process timing by the broadcast receiver which concerns on 2nd Embodiment of this invention. It is a block diagram which shows the function structural example of the broadcast receiving apparatus which concerns on 3rd Embodiment of this invention. It is a flowchart which shows an example of the process by the broadcast receiver which concerns on 3rd Embodiment of this invention. It is a figure which shows an example of the process timing by the broadcast receiver which concerns on 3rd Embodiment of this invention. It is a figure which shows an example of the process timing by the broadcast receiver which concerns on 4th Embodiment of this invention. It is a figure which shows an example of the process timing by the conventional broadcast receiving apparatus.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a functional configuration example of a broadcast receiving apparatus 10 according to the first embodiment of the present invention. The broadcast receiving apparatus 10 shown in FIG. 1 receives a DAB broadcast (an example of a first standard broadcast) and an IP broadcast (an example of a second standard broadcast), and receives the received DAB broadcast audio and IP broadcast. This is a device that can selectively switch between sound and output to the speaker 12.

  As shown in FIG. 1, the broadcast receiving apparatus 10 includes a first receiving unit 101, a first demodulating unit 102, a DAB buffer 103, a second receiving unit 104, a second demodulating unit 105, an IP buffer 106, a time difference calculating unit 107, A comparison unit 108, a delay time calculation unit 109, a delay processing unit 110, and an output control unit 111 are provided.

  Each of the functional blocks 101 to 111 can be configured by any of hardware, DSP (Digital Signal Processor), and software. For example, when configured by software, each of the functional blocks 101 to 111 is actually configured by including a CPU, RAM, ROM, and the like of a computer, and stored in a recording medium such as a RAM, ROM, hard disk, or semiconductor memory. Is realized by operating.

  The first receiver 101 receives a DAB broadcast wave. The first demodulator 102 demodulates the digital audio signal included in the DAB broadcast wave received by the first receiver 101. The DAB buffer 103 (first storage unit) stores audio data included in the DAB broadcast (DAB broadcast demodulated by the first demodulation unit 102) received by the first reception unit 101. The maximum amount of DAB broadcast audio data stored in the DAB buffer 103 is determined in advance.

  The second receiver 104 receives IP broadcast communication data. The second demodulator 105 demodulates the digital audio signal contained in the IP broadcast communication data received by the second receiver 104. The IP buffer 106 (second storage unit) stores audio data included in the IP broadcast received by the second reception unit 104 (the IP broadcast demodulated by the second demodulation unit 105). The maximum amount of IP broadcast audio data stored in the IP buffer 106 is determined in advance.

  The IP broadcast received by the second receiver 104 has the same content as the DAB broadcast received by the first receiver 101. However, the IP broadcast received by the second receiving unit 104 is received with a delay from the DAB broadcast received by the first receiving unit 101. The first receiving unit 101 directly receives a DAB broadcast wave, whereas the second receiving unit 104 receives IP broadcast communication data transmitted from a broadcast station via a provider, an Internet server, or the like. Because it does.

  The output control unit 111 receives the digital audio signal of the DAB broadcast (DAB broadcast demodulated by the first demodulation unit 102) received by the first reception unit 101 and the IP broadcast (second transmission) received by the second reception unit 104. The digital audio signal of the IP broadcast after demodulation by the demodulation unit 105 is selectively switched and output. For example, when the received signal strength of DAB broadcasting is higher than a predetermined threshold, the output control unit 111 switches to DAB broadcasting and outputs it. On the other hand, when the received signal strength of DAB broadcasting falls below a predetermined threshold, the output control unit 111 switches to IP broadcasting and outputs it. That is, the output control unit 111 preferentially outputs a DAB broadcast having a higher quality than the IP broadcast. The audio signal output from the output control unit 111 is amplified by the amplifier 11 and output from the speaker 12 as audio.

  The time difference calculation unit 107 calculates the time difference between the time information assigned to the DAB broadcast audio data and the time information assigned to the IP broadcast audio data. When the IP broadcast audio data is received by the second receiving unit 104, time information is already added. On the other hand, when the DAB broadcast audio data is received by the first receiver 101, time information supplied from a GPS (Global Positioning System) 13 is given.

  The comparison unit 108 compares the DAB broadcast audio data stored in the DAB buffer 103 with the IP broadcast audio data stored in the IP buffer 106, thereby comparing the DAB broadcast audio data stored in the DAB buffer 103. From the above, the same data as the audio data of the IP broadcast stored in the IP buffer 106 is specified.

  In the present embodiment, the comparison unit 108 determines audio data stored in a partial range of the DAB buffer 103 as comparison target data based on the time difference calculated by the time difference calculation unit 107. Then, the comparison unit 108 compares the comparison target data with the IP broadcast audio data stored in the IP buffer 106, thereby comparing the comparison target data with the IP broadcast audio data stored in the IP buffer 106. Identify the same data.

  In particular, in the present embodiment, the comparison unit 108, based on the time difference calculated by the time difference calculation unit 107, in the DAB broadcast audio data stored in the DAB buffer 103, the comparison start position at a position after the head data. And data after the comparison start position are determined as comparison target data. Then, the comparison unit 108 compares the comparison target data with the IP broadcast audio data stored in the IP buffer 106, thereby comparing the comparison target data with the IP broadcast audio data stored in the IP buffer 106. Identify the same data.

  The delay time calculation unit 109 receives the same data specified by the comparison unit 108 from the DAB broadcast audio data stored in the DAB buffer 103, and receives the IP broadcast audio data stored in the IP buffer 106. Based on the above, the delay time of the IP broadcast from the DAB broadcast is calculated. For example, when the reception timing of the same data specified from the DAB broadcast audio data stored in the DAB buffer 103 is 2 seconds before the reception timing of the IP broadcast audio data stored in the IP buffer 106, the delay time The calculation unit 109 calculates the delay time of the IP broadcast from the DAB broadcast as “2 seconds”.

  The delay processing unit 110 performs a delay process (time stretch) on the DAB broadcast audio data according to the delay time calculated by the delay time calculation unit 109. Thus, the delay processing unit 110 synchronizes the output timing of the audio data of DAB broadcast output from the output control unit 111 with the output timing of the audio data of IP broadcast output from the output control unit 111.

[Example of processing by broadcast receiving apparatus 10]
FIG. 2 is a flowchart showing an example of processing by the broadcast receiving apparatus 10 according to the first embodiment of the present invention. The process illustrated in FIG. 2 is executed, for example, when the power of the broadcast receiving apparatus 10 is switched on.

  First, the first receiving unit 101 starts receiving a DAB broadcast (step S202). Next, the first demodulator 102 demodulates the digital audio signal included in the DAB broadcast wave received by the first receiver 101 (step S204). Then, the DAB buffer 103 stores the audio data included in the digital audio signal demodulated by the first demodulator 102 (step S206).

  Further, the second receiving unit 104 starts receiving IP broadcast (step S208). Next, the second demodulator 105 demodulates the digital audio signal included in the IP broadcast communication data received by the second receiver 104 (step S210). Then, the IP buffer 106 stores the audio data included in the digital audio signal demodulated by the second demodulator 105 (step S212). Actually, the process until the DAB broadcast audio data is stored in the DAB buffer 103 (steps S202 to S206) and the process until the IP broadcast audio data is stored in the IP buffer 106 (steps S208 to S212). Are executed in parallel.

  Next, the time difference calculation unit 107 determines whether or not the maximum amount of data is stored in the DAB buffer 103 (step S214). Here, when the time difference calculation unit 107 determines that the data of the maximum data amount is not stored in the DAB buffer 103 (step S214: No), the broadcast receiving device 10 executes the processing after step S202 again.

  On the other hand, when the time difference calculation unit 107 determines that the maximum amount of data has been stored in the DAB buffer 103 (step S214: Yes), the time difference calculation unit 107 acquires time information attached to the audio data of the DAB broadcast. (Step S216). Also, the time difference calculation unit 107 acquires time information given to the audio data of the IP broadcast (step S218). Then, the time difference calculation unit 107 calculates the time difference between the time information given to the DAB broadcast audio data and the time information given to the IP broadcast audio data (step S220).

  Next, the comparison unit 108 determines a comparison start position at a position after the head data in the DAB broadcast audio data stored in the DAB buffer 103 based on the time difference calculated in step S220 (step S222). ). Then, the comparison unit 108 compares the comparison target data after the comparison start position determined in step S222 with the IP broadcast audio data stored in the IP buffer 106, thereby obtaining the IP buffer 106 from the comparison target data. The same data (link point) as the audio data of the IP broadcast stored in is identified (step S224).

  Next, the delay time calculation unit 109 receives the same data identified from the reception timing of the IP broadcast audio data stored in the IP buffer 106 and the comparison target data stored in the DAB buffer 103 in step S224. Based on the timing, the delay time of the IP broadcast from the DAB broadcast is calculated (step S226). Further, the delay processing unit 110 starts delay processing of DAB broadcast audio data output from the output control unit 111 (step S228).

  Thereafter, the delay processing unit 110 determines whether or not the delay time of the IP broadcast calculated in step S226 has been eliminated (step S230). Here, when the delay processing unit 110 determines that the delay time of the IP broadcast has not been eliminated (step S230: No), the delay processing unit 110 executes the determination process of step S230 again.

  On the other hand, when the delay processing unit 110 determines that the delay time of the IP broadcast has been eliminated (step S230: Yes), the delay processing unit 110 ends the delay processing of the DAB broadcast audio data output from the output control unit 111. (Step S232). And the broadcast receiving apparatus 10 complete | finishes a series of processes shown in FIG.

[Example of processing timing]
FIG. 3 is a diagram illustrating an example of processing timing by the broadcast receiving apparatus 10 according to the first embodiment of the present invention. Here, an example will be described in which audio data having the same content is broadcast as “1”, “2”, “3”, “4”,... In both DAB broadcasting and IP broadcasting. Here, one frame of audio data is schematically shown on the assumption that it is audio data of a predetermined time (for example, 1 second).

  As shown in FIG. 3, the DAB broadcast audio data and the IP broadcast audio data have the same contents, but the IP broadcast is transmitted from the broadcast station to the broadcast receiving device via a provider, an Internet server, or the like. Therefore, it is received later than the DAB broadcast. In the example shown in FIG. 3, the IP broadcast is delayed by two frames of audio data than the DAB broadcast.

  Therefore, in the example shown in FIG. 3, the output timing of the DAB broadcast audio data is performed by performing a delay process on the DAB broadcast audio data so that the switching from the DAB broadcast audio output to the IP broadcast audio output is seamless. Are synchronized with the output timing of the audio data of the IP broadcast.

  Specifically, the broadcast receiving apparatus 10 according to the first embodiment receives the audio data of DAB broadcast and IP broadcast when the broadcast receiver 10 is first turned on (timing t1 in FIG. 3) and receives audio data of DAB broadcast and IP broadcast. The DAB broadcast and IP broadcast audio data are sequentially stored in the DAB buffer 103 and the IP buffer 106.

  In the example shown in FIG. 3, the DAB buffer 103 has a capacity for six frames of audio data. The IP buffer 106 has a capacity for one frame of audio data. In FIG. 3, after the broadcast receiving apparatus 10 is switched on, audio data (audio data “1” to “6”) for six frames is first stored in the DAB buffer 103 (FIG. 3). The timing t2) of the DAB buffer 103 and the IP buffer 106 are shown. At this time, the audio data “4” is stored in the IP buffer 106.

  As described above, when the audio data of the maximum data amount (six frames) is stored in the DAB buffer 103, first, the time difference calculation unit 107 first performs the time information of the DAB broadcast audio data and the time information of the IP broadcast audio data. And calculate the time difference. Then, the comparison unit 108 determines a comparison start position in the audio data stored in the DAB buffer 103 based on the calculated time difference. In the example shown in FIG. 3, since the time difference is about two frames of audio data, the audio data “3” three frames before the audio data “6” is determined as a comparison start position with a margin.

  Then, the comparison unit 108 compares the audio data “4” stored in the IP buffer 106 with the audio data “3” and “4” stored in the DAB buffer 103 in order, so that the IP buffer 106 The same data as the audio data “4” stored in the DAB buffer 103 is detected. That is, in this example, the audio data “4” of the same DAB broadcast as the audio data “4” of the IP broadcast is detected by the second comparison.

  Then, the delay time calculation unit 109 calculates the time difference between the reception timing of the IP broadcast audio data “4” and the reception timing of the DAB broadcast audio data “4” as the delay time of the IP broadcast. When the audio data “6” of the DAB broadcast is received, the audio data “4” of the IP broadcast is received, which means that the IP broadcast is delayed by two frames of audio data from the DAB broadcast. is there.

  Further, the delay processing unit 110 time-stretches the DAB broadcast audio data by the required number of frames so that the calculated IP broadcast delay time is eliminated (timing t3 to t4 in FIG. 3). Thereby, the broadcast receiving apparatus 10 eliminates the delay time of the IP broadcast, and the DAB broadcast output timing is synchronized with the output timing of the DAB broadcast and the output timing of the IP broadcast (the state after the timing t4 in FIG. 3). It is possible to switch from output to IP broadcast output.

  In the example shown in FIG. 3, since the audio data stored in the IP buffer 106 and the audio data stored in the DAB buffer 103 are compared twice, the delay time of the IP broadcast is calculated. In addition, processing time for two frames of audio data (timing t2 to t3 in FIG. 3) is spent. That is, the processing time required for calculating the delay time of IP broadcasting is shortened by two frames of audio data compared to the conventional method (see FIG. 11). Therefore, in the example shown in FIG. 3, the timing (timing t4) at which the output timing of DAB broadcast audio data is synchronized with the output timing of IP broadcast audio data (timing t4) is advanced by two frames of audio data. .

  Thus, according to the broadcast receiving apparatus 10 of the first embodiment, the DAB broadcast audio data stored in the DAB buffer 103 is based on the same data as the IP broadcast audio data stored in the IP buffer 106. A comparison process for specifying the same data can be started from a close position. For this reason, the time required for the comparison process for specifying the same data can be shortened, and the comparison process can be terminated earlier. Therefore, according to the broadcast receiving device 10 of the first embodiment, the synchronization timing of two broadcasts for seamlessly switching output audio can be advanced.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 4 is a block diagram showing a functional configuration example of a broadcast receiving apparatus 10 ′ according to the second embodiment of the present invention. The broadcast receiving device 10 ′ shown in FIG. 4 includes a time difference calculating unit 107 ′ and a comparing unit 108 ′ instead of the time difference calculating unit 107 and the comparing unit 108, so that the broadcast receiving device 10 of the first embodiment (FIG. 1).

  The time difference calculation unit 107 ′ calculates the time difference between the time information given to the DAB broadcast audio data and the time information given to the IP broadcast audio data. The time difference calculation unit 107 ′ of the second embodiment is different from the time difference calculation unit 107 of the first embodiment in that the time difference is calculated without waiting for the audio data having the maximum data amount to be stored in the DAB buffer 103. . Here, time information is given to the audio data of the DAB broadcast at a relatively short fixed interval (for example, 1 second) by the GPS 13. Time information is given to IP broadcast audio data at a relatively long constant interval (for example, 2 seconds). In response to this, the time difference calculation unit 107 'calculates the time difference between the two pieces of time information when both the DAB broadcast sound data and the IP broadcast sound data are given time information.

  If the time difference is calculated by the time difference calculation unit 107 ′ before the maximum amount of audio data is stored in the DAB buffer 103, the comparison unit 108 ′ compares the audio data stored in the DAB buffer 103 at that time. By determining the target data and comparing the comparison target data with the IP broadcast audio data stored in the IP buffer 106, the comparison target data is identical to the IP broadcast audio data stored in the IP buffer 106. Identify the data.

[Example of processing by broadcast receiving apparatus 10 ']
FIG. 5 is a flowchart showing an example of processing by the broadcast receiving device 10 ′ according to the second embodiment of the present invention. The process illustrated in FIG. 5 is executed, for example, when the power of the broadcast receiving device 10 ′ is switched on.

  First, the first receiving unit 101 starts receiving a DAB broadcast (step S502). Next, the first demodulator 102 demodulates the digital audio signal included in the DAB broadcast wave received by the first receiver 101 (step S504). Then, the DAB buffer 103 stores audio data included in the digital audio signal demodulated by the first demodulator 102 (step S506).

  In addition, the second receiving unit 104 starts receiving IP broadcast (step S508). Next, the second demodulator 105 demodulates the digital audio signal included in the IP broadcast communication data received by the second receiver 104 (step S510). Then, the IP buffer 106 stores the audio data included in the digital audio signal demodulated by the second demodulator 105 (step S512).

  Next, it is determined whether or not the time difference calculation unit 107 ′ has been able to acquire both the time information given to the DAB broadcast audio data and the time information given to the IP broadcast audio data. (Step S514). Here, when the time difference calculation unit 107 ′ determines that both the time information of the DAB broadcast and the time information of the IP broadcast cannot be acquired (step S514: No), the broadcast receiving apparatus 10 ′ performs step S502 and subsequent steps. Execute the process again.

  On the other hand, when the time difference calculation unit 107 ′ determines that both the time information of the DAB broadcast and the time information of the IP broadcast can be acquired (step S514: Yes), the time difference calculation unit 107 ′ acquires the acquired DAB broadcast. The time difference between the time information and the IP broadcast time information is calculated (step S516). Then, the comparison unit 108 ′ uses the audio data stored in the DAB buffer 103 at the time when the time difference is calculated as comparison target data, and compares the comparison target data with the IP broadcast audio data stored in the IP buffer 106. As a result, the same data (link point) as the IP broadcast audio data stored in the IP buffer 106 is identified from the comparison target data (step S518).

  The delay time calculation unit 109 receives the IP broadcast audio data stored in the IP buffer 106 and the same data received from the comparison target data stored in the DAB buffer 103 in step S518. Based on the above, the delay time of the IP broadcast from the DAB broadcast is calculated (step S520). Further, the delay processing unit 110 starts delay processing of DAB broadcast audio data output by the output control unit 111 (step S522).

  Thereafter, the delay processing unit 110 determines whether or not the delay time of the IP broadcast calculated in step S520 has been eliminated (step S524). Here, when the delay processing unit 110 determines that the delay time of the IP broadcast has not been eliminated (step S524: No), the delay processing unit 110 executes the determination processing of step S524 again.

  On the other hand, when the delay processing unit 110 determines that the delay time of the IP broadcast has been eliminated (step S524: Yes), the delay processing unit 110 ends the delay processing of the DAB broadcast audio data output from the output control unit 111. (Step S526). Then, the broadcast receiving apparatus 10 'ends the series of processes shown in FIG.

[Example of processing timing]
FIG. 6 is a diagram illustrating an example of processing timing by the broadcast receiving device 10 ′ according to the second embodiment of the present invention. In FIG. 6, the contents and reception timing of audio data of IP broadcast and DAB broadcast are the same as those in the first embodiment (FIG. 3), and thus the description thereof is omitted.

  When the broadcast receiving apparatus 10 ′ of the second embodiment first receives the DAB broadcast and IP broadcast audio data when the broadcast receiving apparatus 10 ′ is turned on (timing t1 in FIG. 6) and receives the audio data of the DAB broadcast, the received DAB broadcast is received. And the audio data of the IP broadcast are sequentially stored in the DAB buffer 103 and the IP buffer 106.

  In the example shown in FIG. 6, the DAB buffer 103 has a capacity for six frames of audio data. The IP buffer 106 has a capacity for one frame of audio data. In FIG. 6, when the power of the broadcast receiving apparatus 10 ′ is switched to ON, four frames of audio data (audio data “1” to “4”) are first stored in the DAB buffer 103 (FIG. 6). 6, the state of the DAB buffer 103 and the IP buffer 106 is shown. At this time, the audio data “2” is stored in the IP buffer 106.

  At this time, time information is given to the audio data of DAB broadcast, and time information is also given to the audio data of IP broadcast. Therefore, at this time, the time difference calculation unit 107 ′ calculates the time difference between the time information given to the DAB broadcast audio data and the time information given to the IP broadcast audio data. As shown in FIG. 6, time information is given to DAB broadcast audio data at a relatively short fixed interval (one frame at a time), but IP broadcast audio data has a relatively short fixed interval (2). Time information is given for each frame). For this reason, the time difference calculation unit 107 ′ calculates the time difference between the two pieces of time information at the timing when the time information is given to both the DAB broadcast audio data and the IP broadcast audio data.

  At the time when the time difference is calculated in this way, the comparison unit 108 ′ uses the audio data “1” to “4” stored in the DAB buffer 103 as comparison target data, and compares the comparison target data with the IP buffer. The process of specifying the same data as the audio data “2” stored in 106 is started. Specifically, the comparison unit 108 ′ compares the audio data “2” stored in the IP buffer 106 with the audio data “1” and “2” stored in the DAB buffer 103 in order. The same data as the audio data “2” stored in the IP buffer 106 is detected from the DAB buffer 103. That is, in this example, the second comparison makes it possible to detect the same DAB broadcast audio data “2” as the IP broadcast audio data “2”.

  Then, the delay time calculation unit 109 calculates the time difference between the reception timing of the IP broadcast audio data “2” and the reception timing of the DAB broadcast audio data “2” as the delay time of the IP broadcast. When the audio data “2” of the IP broadcast is received when the audio data “4” of the DAB broadcast is received, the IP broadcast is delayed by two frames of audio data from the DAB broadcast. is there.

  Furthermore, the delay processing unit 110 time-stretches the DAB broadcast audio data by the required number of frames so that the calculated IP broadcast delay time is eliminated (timing t3 to t4 in FIG. 6). As a result, the broadcast receiving apparatus 10 ′ eliminates the delay time of the IP broadcast, and the DAB broadcast is in a state in which the output timing of the DAB broadcast and the output timing of the IP broadcast are synchronized (state after timing t4 in FIG. 6). It is possible to switch from the output of IP to the output of IP broadcast.

  In the example shown in FIG. 6, since the audio data stored in the IP buffer 106 and the audio data stored in the DAB buffer 103 are compared twice, the delay time of the IP broadcast is calculated. In addition, processing time for two frames of audio data (timing t2 to t3 in FIG. 3) is spent. That is, the processing time required for calculating the delay time of IP broadcasting is shortened by two frames of audio data compared to the conventional method (see FIG. 11). Further, in the example shown in FIG. 6, the start timing of the IP broadcast delay time is advanced by two frames of audio data compared to the prior art. For this reason, in the example shown in FIG. 6, the timing (timing t4) at which the output timing of the audio data of DAB broadcasting and the output timing of the audio data of IP broadcasting are synchronized is advanced by 4 frames of audio data than before. .

  As described above, according to the broadcast receiving apparatus 10 ′ of the second embodiment, the DAB broadcast audio stored in the DAB buffer 103 is not waited for the audio data having the maximum data amount stored in the DAB buffer 103. A comparison process for identifying the same data as the audio data of the IP broadcast stored in the IP buffer 106 from the data can be started. Further, since the start timing of the comparison process is advanced, the same data to be specified from the DAB buffer 103 can be made closer to the head of the DAB buffer 103 (that is, the start position of the comparison process). For this reason, since the start timing of the comparison process for specifying the same data can be advanced and the time required for the comparison process can be shortened, the comparison process can be completed earlier. Therefore, according to the broadcast receiving apparatus 10 ′ of the second embodiment, the synchronization timing of two broadcasts for seamlessly switching output audio can be advanced.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 7 is a block diagram illustrating a functional configuration example of a broadcast receiving device 10 ″ according to the third embodiment of the present invention. 7 includes a time difference calculation unit 107 ′ and a delay processing unit 110 ′ instead of the time difference calculation unit 107 and the delay processing unit 110, and the IP buffer 106 and the comparison unit 108. , Which is different from the broadcast receiving apparatus 10 of the first embodiment (see FIG. 1) in that the delay time calculation unit 109 is not provided.

  The time difference calculation unit 107 ′ of the third embodiment is the same as the time difference calculation unit 107 ′ of the second embodiment, and calculates the time difference without waiting for the audio data having the maximum data amount to be stored in the DAB buffer 103. To do. The delay processing unit 110 ′ performs a delay process on the audio data of DAB broadcast according to the time difference calculated by the time difference calculation unit 107 ′. Specifically, when the time difference is calculated by the time difference calculation unit 107 ′, the delay processing unit 110 ′ immediately starts delay processing for the DAB broadcast audio data. Accordingly, the delay processing unit 110 ′ synchronizes the output timing of the DAB broadcast audio data output from the output control unit 111 with the output timing of the IP broadcast audio data output from the output control unit 111.

[Example of processing by broadcast receiving apparatus 10 '']
FIG. 8 is a flowchart showing an example of processing by the broadcast receiving device 10 ″ according to the third embodiment of the present invention. The process shown in FIG. 8 is executed, for example, when the power of the broadcast receiving apparatus 10 ″ is switched on.

  First, the first receiving unit 101 starts receiving DAB broadcast (step S802). Next, the first demodulator 102 demodulates the digital audio signal included in the DAB broadcast wave received by the first receiver 101 (step S804). Then, the DAB buffer 103 stores audio data included in the digital audio signal demodulated by the first demodulator 102 (step S806).

  Also, the second receiving unit 104 starts receiving IP broadcast (step S808). Next, the second demodulator 105 demodulates the digital audio signal included in the IP broadcast communication data received by the second receiver 104 (step S810).

  Next, it is determined whether or not the time difference calculation unit 107 ′ has been able to acquire both the time information given to the DAB broadcast audio data and the time information given to the IP broadcast audio data. (Step S812). Here, when the time difference calculation unit 107 ′ determines that both the time information of the DAB broadcast and the time information of the IP broadcast cannot be acquired (step S812: No), the broadcast receiving apparatus 10 ′ performs step S802 and subsequent steps. Execute the process again.

  On the other hand, when the time difference calculation unit 107 ′ determines that both the time information of the DAB broadcast and the time information of the IP broadcast can be acquired (step S812: Yes), the time difference calculation unit 107 ′ acquires the acquired DAB broadcast. The time difference between the time information and the time information of the IP broadcast is calculated (step S814). Further, the delay processing unit 110 ′ starts delay processing of DAB broadcast audio data output from the output control unit 111 (step S 816).

  Thereafter, the delay processing unit 110 'determines whether or not the time difference calculated in step S814 has been eliminated (step S818). Here, when the delay processing unit 110 'determines that the time difference calculated in step S814 has not been eliminated (step S818: No), the delay processing unit 110' executes the determination processing in step S818 again.

  On the other hand, when the delay processing unit 110 ′ determines that the time difference calculated in step S814 has been eliminated (step S818: Yes), the delay processing unit 110 ′ delays the DAB broadcast audio data output by the output control unit 111. The process ends (step S820). Then, the broadcast receiving apparatus 10 '' ends the series of processes shown in FIG.

[Example of processing timing]
FIG. 9 is a diagram showing an example of processing timings by the broadcast receiving device 10 ″ according to the third embodiment of the present invention. In FIG. 9, the contents and reception timing of audio data of IP broadcast and DAB broadcast are the same as those in the first embodiment (FIG. 3), and thus the description thereof is omitted.

  When the broadcast receiving apparatus 10 '' of the third embodiment is turned on (timing t1 in FIG. 9) and receives audio data of DAB broadcast and IP broadcast, the time difference calculation is performed. The unit 107 ′ tries to acquire time information from each of the DAB broadcast and the IP broadcast. And time difference calculation part 107 'will calculate the time difference of the time information acquired from DAB broadcast, and the time information acquired from IP broadcast, if time information is acquired from each of DAB broadcast and IP broadcast.

  In the example shown in FIG. 9, when the audio data (audio data “2”) of the second frame of the IP broadcast is received after the power of the broadcast receiving device 10 ″ is turned on (timing in FIG. 9). t2) Time information (shown as “T” in FIG. 9) is acquired from each of the DAB broadcast and the IP broadcast, and the time difference between these two pieces of time information is calculated (timing t2 in FIG. 9). ). In this example, approximately two frames of audio data are calculated as the time difference between the two time information.

  When the time difference is calculated in this way, the delay processing unit 110 ′ immediately starts the delay processing of the audio data of DAB broadcast. Specifically, the delay processing unit 110 ′ time-stretches the DAB broadcast audio data by the required number of frames so that the calculated time difference is eliminated (timing t2 to t3 in FIG. 9). As a result, the broadcast receiving apparatus 10 '' eliminates the delay time of the IP broadcast, and the DAB broadcast output timing and the IP broadcast output timing are synchronized (state after the timing t3 in FIG. 9). It is possible to switch from broadcast output to IP broadcast output.

  In the example shown in FIG. 9, the DAB broadcast is performed based on the time difference between the DAB broadcast time information and the IP broadcast time information without performing the comparison process (time difference calculation process) described in the first and second embodiments. Delay processing is performed. For this reason, in the example shown in FIG. 9, the timing at which the audio data output timing of DAB broadcast and the output timing of the IP broadcast audio data are synchronized (timing t3 in FIG. 9) is four frames earlier than the conventional case. It has been.

  As described above, according to the broadcast receiving device 10 '' of the third embodiment, when the time difference between the time information of the DAB broadcast audio data and the time information of the IP broadcast audio data is calculated, the time difference is set to IP. It can be regarded as the broadcast delay time, and the delay processing of the audio data of the DAB broadcast can be started immediately. For this reason, according to the broadcast receiving apparatus 10 '' of the third embodiment, the synchronization timing of the two broadcasts for seamlessly switching the output audio can be advanced.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described with reference to FIG. The fourth embodiment is implemented by combining the first embodiment and the second embodiment. That is, a configuration in which the comparison process is started when the time difference between the time information of the DAB broadcast and the time information of the IP information is calculated without waiting for the maximum amount of audio data to be stored in the DAB buffer 103; Based on the calculated time difference, the audio data stored in the DAB buffer 103 is combined with a configuration for determining the comparison start position at a position after the head data.

  Hereinafter, with reference to FIG. 10, an example of processing timing by the broadcast receiving apparatus of the fourth embodiment will be described. FIG. 10 is a diagram showing an example of processing timing by the broadcast receiving apparatus according to the fourth embodiment of the present invention. In the example shown in FIG. 10, the DAB buffer has a capacity for 15 frames of audio data. In the example shown in FIG. 10, the IP broadcast is delayed by four frames of audio data from the DAB broadcast. In the example shown in FIG. 10, time information is assigned to each frame of audio data in the DAB broadcast audio data, and time information is assigned to every four frames of audio data in the IP broadcast audio data. .

  Further, in FIG. 10, when the broadcast receiving apparatus is turned on, audio data for eight frames (audio data “1” to “8”) is first stored in the DAB buffer (FIG. 10). Timing t2) of the DAB buffer and the IP buffer. At this time, the audio data “4” is stored in the IP buffer.

  At this time, the time information is assigned to the audio data “8” of DAB broadcast, and the time information is also assigned to the audio data “4” of IP broadcast. For this reason, at this point, the broadcast receiving apparatus calculates the time difference between the time information acquired from the DAB broadcast and the time information acquired from the IP broadcast.

  Then, the broadcast receiving apparatus determines a comparison start position in the audio data stored in the DAB buffer based on the calculated time difference. In the example shown in FIG. 10, since the calculated time difference is about four frames of audio data, the audio data “3” five frames before the audio data “8” is determined as a comparison start position with a margin. Yes.

  Then, the broadcast receiving device compares the audio data “4” stored in the IP buffer with the audio data “3” and “4” stored in the DAB buffer in order, and stores them in the IP buffer. The same data as the audio data “4” is detected from the DAB buffer. That is, in this example, the audio data “4” of the same DAB broadcast as the audio data “4” of the IP broadcast is detected by the second comparison.

  Then, the broadcast receiving apparatus calculates the time difference between the reception timing of the IP broadcast audio data “4” and the reception timing of the DAB broadcast audio data “4” as the delay time of the IP broadcast. When the audio data “4” of the IP broadcast is received when the audio data “8” of the DAB broadcast is received, the IP broadcast is delayed by 4 frames of audio data from the DAB broadcast. is there.

  Furthermore, the broadcast receiving apparatus time-stretches the DAB broadcast audio data by the required number of frames so that the calculated delay time of the IP broadcast is eliminated (timing t3 to t4 in FIG. 10). Thereby, the broadcast receiving apparatus eliminates the delay time of the IP broadcast, and the output of the DAB broadcast is in a state where the output timing of the DAB broadcast and the output timing of the IP broadcast are synchronized (state after timing t4 in FIG. 10). To IP broadcast output.

  In the example shown in FIG. 10, the comparison process is started when 8 frames of audio data smaller than the maximum data amount (15 frames) are stored in the DAB buffer. For this reason, compared with the conventional method in which the comparison process is started when the maximum amount of audio data is stored in the DAB buffer, the start timing of the comparison process is advanced by 7 frames of audio data.

  In the example shown in FIG. 10, the comparison process is started from the audio data “3” stored in the DAB buffer based on the calculated time difference. For this reason, compared with the conventional method in which the comparison process is started from the head data (audio data “1”), the processing time for calculating the delay time of the IP broadcast is shortened by two frames of audio data.

  For this reason, according to the broadcast receiving apparatus of the fourth embodiment, the synchronization timing of two broadcasts for seamlessly switching output audio can be greatly advanced as compared with the conventional method.

  In the first to fourth embodiments, the DAB broadcast is applied as the first standard broadcast and the IP broadcast is applied as the second standard broadcast. However, the present invention is not limited to this. For example, FM broadcast may be applied as the first standard broadcast, and IP broadcast may be applied as the second standard broadcast. Further, DAB broadcast may be applied as the first standard broadcast, and FM broadcast may be applied as the second standard broadcast.

  In addition, each of the above-described embodiments is merely an example of a specific example for carrying out the present invention, and the technical scope of the present invention should not be construed in a limited manner. That is, the present invention can be implemented in various forms without departing from the gist or the main features thereof.

10, 10 ′, 10 ″ Broadcast receiver 11 Amplifier 12 Speaker 13 GPS
101 First receiver 102 First demodulator 103 DAB buffer (first storage)
104 Second receiver 105 Second demodulator 106 IP buffer (second storage)
107, 107 ′ time difference calculation unit 108, 108 ′ comparison unit 109 delay time calculation unit 110, 110 ′ delay processing unit 111 output control unit

Claims (7)

A first receiver for receiving a first standard broadcast;
A second receiver for receiving a second standard broadcast delayed from the first standard broadcast;
An output controller for selectively switching and outputting the first standard broadcast data received by the first receiver and the second standard broadcast data received by the second receiver;
A first storage unit for temporarily storing broadcast data of the first standard received by the first reception unit;
A second storage unit for temporarily storing broadcast data of the second standard received by the second reception unit;
The first standard broadcast data stored in the first storage unit and the second standard broadcast data stored in the second storage unit are compared to store the first standard broadcast data in the first storage unit. A comparison unit that identifies the same data as the second standard broadcast data stored in the second storage unit from the first standard broadcast data;
Based on the reception timing of the same data specified from the broadcast data of the first standard by the comparison unit and the reception timing of the broadcast data of the second standard stored in the second storage unit, the first data A delay time calculating unit for calculating a delay time of the second standard broadcast from the standard broadcast;
By performing a delay process on the first standard broadcast data according to the delay time calculated by the delay time calculation unit, the output timing of the first standard broadcast data is set to the second standard broadcast data. A broadcast receiving device including a delay processing unit that synchronizes with the output timing of
A time difference calculating unit that calculates a time difference between the time information given to the first standard broadcast data and the time information given to the second standard broadcast data;
The comparison unit determines broadcast data stored in a partial range of the first storage unit as comparison target data according to the calculation of the time difference by the time difference calculation unit, and performs the comparison with the comparison target data. The broadcast receiving apparatus characterized in that the same data is identified from the comparison target data. The comparison unit determines a comparison start position after the head data in the first standard broadcast data stored in the first storage unit based on the time difference calculated by the time difference calculation unit, The data after the comparison start position is determined as the comparison target data, and the same data is specified from the comparison target data by performing the comparison with respect to the comparison target data. Broadcast receiving device. When the time difference is calculated by the time difference calculation unit before the first standard broadcast data having the predetermined maximum data amount is stored in the first storage unit, the comparison unit calculates the time difference. The broadcast data of the first standard stored in the first storage unit at the time is determined as the comparison target data, and the same data is identified from the comparison target data by performing the comparison with the comparison target data The broadcast receiving apparatus according to claim 1, wherein: The comparison unit is calculated by the time difference calculation unit when the time difference is calculated by the time difference calculation unit before the first standard broadcast data having the predetermined maximum data amount is stored in the first storage unit. Based on the time difference that has been determined, for the first standard broadcast data stored in the first storage unit at the time when the time difference was calculated, determine a comparison start position after the head data, The broadcast reception according to claim 1, wherein the same data is specified from the comparison target data by determining data after the comparison start position as comparison target data and performing the comparison with the comparison target data. apparatus.   5. The broadcast receiving apparatus according to claim 1, wherein the broadcast of the first standard is FM broadcast, and the broadcast of the second standard is IP broadcast. 6.   5. The broadcast receiving apparatus according to claim 1, wherein the first standard broadcast is a DAB broadcast, and the second standard broadcast is an IP broadcast. 6. An output control method by a broadcast receiving apparatus including an output control unit that selectively switches and outputs a first standard broadcast and a second standard broadcast delayed from the first standard broadcast,
A first storage step in which the first storage unit of the broadcast receiving device temporarily stores the broadcast data of the first standard;
A second storage step in which the second storage unit of the broadcast receiving device temporarily stores the broadcast data of the second standard;
A time difference calculating step of calculating a time difference between time information given to the first standard broadcast data and time information given to the second standard broadcast data; ,
The comparison unit of the broadcast receiving apparatus determines broadcast data stored in a partial range of the first storage unit as comparison target data according to the calculation of the time difference in the time difference calculation step, and the comparison target data And the second standard broadcast data stored in the second storage unit by comparing the second standard broadcast data stored in the second storage unit with the second standard broadcast data stored in the second storage unit. A comparison process to identify the data;
The delay time calculation unit of the broadcast receiving apparatus receives the same standard data received from the comparison target data in the comparison step and receives the second standard broadcast data stored in the second storage unit. A delay time calculating step for calculating a delay time of the second standard broadcast from the first standard broadcast based on the timing;
The delay processing unit of the broadcast receiving device performs a delay process on the first standard broadcast data according to the delay time calculated in the delay time calculation step, so that the broadcast data of the first standard is A delay processing step of synchronizing the output timing with the output timing of the broadcast data of the second standard.

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