JP4313689B2 - Digital broadcast receiving apparatus, method and program thereof - Google Patents

Description

  The present invention relates to a transmission system that digitally transmits information such as audio, moving images, or characters via a transmission path including terrestrial and satellite waves, and in particular, corrects reproduction time information on the reception side, The present invention relates to a digital broadcast transmitting apparatus and a digital broadcast receiving apparatus that reproduce in synchronization.

In recent years, digital broadcasting that transmits information such as audio, moving images, or characters as digital data via a transmission path including ground waves and satellite waves has started.
For example, in the prior art disclosed in Patent Document 1, the transmitting device packetizes and transmits a moving image in units of frames, and the receiving device enables correction and complementation of reproduction time information (time stamp) in the packet. Yes. Similarly, the audio signal is packetized in units of audio frames, which are playback units, so that the playback side information can be corrected and complemented on the receiving side in the same way as with moving images.

More specifically, the receiving apparatus determines whether or not the reproduction time information (PTS: Presentation Time Stamp) in the received packet is correct based on the reproduction time information of the immediately previous packet and the frame time. That is, the correctness determination is performed by comparing the PTS of the received packet with the value obtained by adding the reference time such as the frame length to the previous PTS. Further, when it is determined to be correct, the received PTS is used, and when it is determined to be incorrect, a value obtained by adding a reference time to the previous PTS is used as a correction value.
JP 2002-135777 A

However, according to the above-described prior art, there is a problem that the reproduction time information may not be corrected or complemented when a plurality of frames are packetized instead of one frame per packet.
More specifically, since an audio signal has a lower bit rate than a moving image signal, it is common to packetize a plurality of frames into one packet. This is because making one packet in one frame increases redundancy. When audio signals of a plurality of frames are packetized into one packet, reproduction time information is rarely added to all packets, and there are packets to which no reproduction time information is added.

  As described above, when a plurality of frames are packetized into one packet and the reproduction time information or frame is lost due to an error when the reproduction time information is not added to all packets, As a result of continuing the reproduction by the stuffing, a reproduction deviation such as a skipping sound or a synchronization deviation with the moving image occurs. Thereafter, the reproduction timing is restored when new reproduction time information is detected. If the detection of new playback time information is greatly delayed from the time of the error, playback during that time will continue to be out of sync due to the last adjustment, and even if no error is included in the detection time of the new playback time information, the playback timing will return. Sound skipping and sound interruption occurred.

  In other words, in the above prior art, the unit of packetization is limited to one frame, and correction of reproduction time information is performed when a plurality of frames are packetized into one packet in a low bit rate system such as an audio signal. There is a problem that can not be. In addition, when the reproduction time information is not added to all packets and an error occurs, there is a problem that the reproduction timing is not corrected until the next reproduction time information is detected.

  In order to solve the above problems, the present invention makes it possible to correct or complement reproduction time information regardless of the number of frames in a packet, and to facilitate return from an error state to a normal state on the receiving side. It is an object to provide a device, a digital broadcast receiving device, a method thereof, and a program.

In order to solve the above problems, a digital broadcast transmission apparatus according to the present invention includes a packet generation unit that generates a packet including data, a packetization information generation unit that generates packetization information related to a data amount of the data, the packet, and the packet Multiplexing means for multiplexing packetized information and generating multiplexed data, and transmitting means for transmitting the multiplexed data.
Further, the digital broadcast receiving apparatus is based on the packetized information separated by the separating means for separating the packet including the data from the received multiplexed data and the packetized information related to the data amount of the data. Determining means for determining whether the reproduction time set in the packet is correct or not, and a correction means for correcting the reproduction time of the data based on the packetization information when the determination means determines that the error has occurred. Prepare.

  According to this configuration, the digital broadcast receiving apparatus determines whether or not the reproduction time is correct based on the packetization information, and corrects the reproduction time based on the packetization information when it is determined to be an error. It is easy to return from the normal state to the normal state. In addition, correctness determination and correction can be easily performed regardless of the amount of data in each packet, that is, even when the amount of data varies from packet to packet.

Here, the digital broadcast transmitting apparatus and the digital broadcast receiving apparatus are configured to indicate any of the number of frames of data in the packet, the size of the data in the packet, and the reproduction time length of the data in the packet as the packetization information. Also good.
According to this configuration, the digital broadcast receiving apparatus can predict the reproduction time length of the packet from the packetization information regardless of the size of the packet.

  Here, in the digital broadcast transmission apparatus, the packetization information generation means generates packetization information for each packet generated by the packet generation means, and the multiplexing means responds from transmission of the packetization information by the transmission means. Multiplexing may be performed so that the time until transmission of a packet to be transmitted is a certain time or longer. The fixed time may be configured to be a time required for extracting packetized information from multiplexed data received by a receiving device. Further, in the digital broadcast receiving apparatus, the determination unit may be configured to determine whether the reproduction time set in the packet is correct or not by using packetization information received a predetermined time or more before the currently received packet. .

According to this configuration, the digital broadcast receiving apparatus can obtain the reproduction time length of the packet from the packetization information before analyzing the reproduction time of the packet, so that it is easy to determine and correct the packet reproduction time. Can be done.
Here, in the digital broadcast transmitting apparatus, the multiplexing means further includes a packet generated when the packetized information generated by the packetized information generating means has the same content as the packetized information multiplexed immediately before. It is also possible to adopt a configuration in which multiplexing of the digitized information is omitted. Further, in the digital broadcast receiving apparatus, when the packetization information is not received a certain time before the packet, the determination means uses the packetization information received immediately before to determine whether the reproduction time set in the packet is correct or incorrect. It is good also as a structure which determines.

According to this configuration, packetization information and packets are transmitted one-to-many instead of one-to-one, and data transmission efficiency can be improved.
Here, the multiplexing means is further configured so that the packetized information generated by the packetized information generating means is constant from the transmission of the immediately previous packetized information even if the packetized information has the same contents as the packetized information that was multiplexed immediately before. When the time interval is exceeded, the multiplexing may be omitted.

According to this configuration, since the packetization information is transmitted at least once during the certain time interval, the digital broadcast receiving apparatus can correct the error during the certain time interval at the latest even if reception starts in the middle of the data. Judgment and correction can be performed correctly.
Here, the multiplexing means may be configured to omit multiplexing of packetization information when the number of frames in all packets is fixed at two or more values by the packet generation means.

In this case, by notifying the receiving apparatus of the number of frames in advance, correctness determination and correction can be correctly performed without performing packetization information analysis processing.
Here, the packet generation means generates a packetized elementary stream packet, and the multiplexing means converts the packet generated by the packet generation means into one or more transport stream packets having a fixed length. And may be multiplexed. The multiplexing means may be configured to convert and multiplex the packetization information generated by the packetization information generation means into section format data.

  According to this configuration, for example, data can be transmitted and received as a so-called MPEG-2 transport stream.

According to the digital broadcast transmission device and the digital broadcast reception device of the present invention, it is possible to easily determine whether or not the reproduction time information is correct and correct regardless of the amount of data in the packet. Returning to a normal state can be facilitated.
In addition, the digital broadcast transmission method, the digital broadcast reception method, the program executed on the computer in the digital broadcast transmission apparatus, the program executed on the computer in the digital broadcast reception apparatus of the present invention are configured and operated in the same manner as described above. Has an effect.

  Embodiments of the present invention will be described below with reference to the drawings. In the present embodiment, a terrestrial digital audio broadcast transmission system that transmits an MPEG-2 transport stream (hereinafter, TS) as broadcast data will be described as an example. As for the transmission system and encoding / multiplexing system of terrestrial digital audio broadcasting, ARIB STD-B29 “Transmission system of terrestrial digital audio broadcasting” standard and ARIB STD-B32 “video encoding in digital broadcasting, The details are described in the "voice encoding and multiplexing system" standard.

FIG. 1 is a block diagram showing a configuration of a digital broadcast transmission / reception system according to an embodiment of the present invention. The digital broadcast transmission / reception system includes a digital broadcast transmission device 1 that transmits information such as audio, moving images, or characters in digital form via a transmission path including ground waves and satellite waves, and digital broadcast that receives digital broadcasts. The receiving apparatus 2 is comprised.
The digital broadcast transmitting apparatus 1 includes an encoding unit 11, a packetizing unit 12, a system encoding unit 13, a modulating unit 14, and an antenna 15, and includes packetization information related to a packet including audio data and a data amount of audio data included in the packet. Is multiplexed with TS and transmitted.

The digital broadcast receiving apparatus 2 includes an antenna 21, a demodulation unit 22, a system decoding unit 23, a section analysis unit 24, a packet analysis unit 25, a decoding unit 26, and a system clock generation unit 27, and is based on the received packetization information. Thus, the correctness / correction of the reproduction time set in each packet is determined and corrected.
In the digital broadcast transmitting apparatus 1, the encoding unit 11 encodes an audio signal to be broadcast into a bit stream of MPEG-2 AAC (Advanced Audio coding) (hereinafter, AAC).

The packetizing unit 12 packetizes the AAC bit stream encoded by the encoding unit 11 into a PES (Packetized Elementary Stream) packet, and further outputs the number of AAC audio frames in the PES packet as packetized information.
The system encoding unit 13 divides and converts the PES packet packetized by the packetizing unit 12 into fixed-length TS packets, and multiplexes the converted TS packets and packetization information. At that time, the system encoding unit 13 converts the packet information into section-format TS packets and multiplexes them.

The modulation unit 14 modulates the TS packet supplied to the system encoding unit 13 and output from the system encoding unit 13 into a broadcast wave, and transmits the modulated information via the transmission antenna 15.
In the digital broadcast receiver 2, the demodulator 22 demodulates the digital broadcast wave received via the receiving antenna 21 to output a TS packet. The system decoder 23 analyzes the TS packet output from the demodulator 22. Then, the TS packet including the audio signal and the section-type TS packet are separated, the data portion is extracted from the TS packet including the audio signal, and the PES packet is reconfigured. The reconstructed PES packet is output to the packet analysis unit 25. The TS packet including the section format packetization information is output to the section analysis unit 24. The packetization information indicates that the PES packet is composed of four AAC frames, for example.

The section analysis unit 24 analyzes the section-format TS packet output from the system decoding unit 23 , separates the packetization information and the TS packet, and outputs the packetization information to the packet analysis unit 25 .
The packet analysis unit 25 extracts the PTS and the audio frame in the PES packet, and outputs the audio frame to the decoding unit 26 at the time indicated by the PTS where the correctness / incorrectness determination and correction are performed.

The decoding unit 26 decodes the AAC audio frame output from the packet analysis unit 25 and outputs an audio signal.
The system clock generator 27 supplies a system time clock serving as a reference for operation to the decoder 26, the packet analyzer 25, and the section analyzer 24.
FIG. 2 is a functional block diagram showing a detailed configuration of the packet analysis unit 25. The packet analysis unit 25 includes an encoded signal extraction unit 251, a reproduction time information extraction unit 252, and an error detection correction unit 253.

The encoded signal extraction unit 251 receives the PES packet output from the system decoding unit 23, analyzes the PES packet, extracts the data part, reconstructs and outputs the AAC bitstream.
The reproduction time information extraction unit 252 analyzes the PES packet output from the system decoding unit 23, extracts the PTS that is reproduction time information, and outputs it. At that time, the reproduction time information extraction unit 252 extracts and outputs a PTS if the PES packet includes the PTS. If PTS is not included, for example, an invalid value is output as a NULL signal or PTS, and information notifying that PTS is not included is output.

  The error detection / correction unit 253 holds the PTS added to the previous PES packet, and the reproduction time information extraction unit 252 extracts it based on the number of AAC bitstream frames included in the current PES packet. If the correct PTS is determined and the error is determined to be an error, the correct PTS is predicted, and the predicted PTS is output in place of the PTS determined to be an error. Similarly, when a PTS is not included in the PES packet header, similarly, the predicted PTS is output. In the case of an AAC audio frame, the predicted PTS can be easily calculated using a sampling frequency or the like because one frame time is 1024 samples. Therefore, it is possible to determine whether or not the PTS added to the PES packet is correct based on the number of AAC bitstream frames constituting the PES packet.

FIG. 3A to FIG. 3D are explanatory diagrams of PES packets, TS packets, sections, and TS generated in the digital broadcast transmitting apparatus 1.
FIG. 3A shows a PES packet generated by the packetizing unit 12. Each of the PES packets p1, p2, etc. is a variable-length packet, and consists of a header portion including PTS and a payload portion including an AAC audio frame. However, the header part may not include PTS. The payload portion can include a plurality of AAC audio frames. This number of frames can be changed dynamically. For example, the PES packet p1 is divided into TS packets T11 to T1n having a fixed length (188 bytes) as shown in FIG.

  FIG. 3C shows a section-format TS packet generated by the system encoding unit 13 from the packetization information generated by the packetizing unit 12. The packetization information is generated simultaneously with the PES packet and indicates the number of frames in the PES packet. For example, the section S1 indicates the number of audio frames N1 (for example, 4) in the PES packet p1. Similarly, sections S2 and S3 indicate the frame numbers N2 and N3 of the PES packets p2 and P3.

  The TS packet shown in FIG. 3B and the section shown in FIG. 3C are multiplexed as shown in FIG. At that time, the system encoding unit 13 multiplexes so that the time from the transmission of the section to the transmission of the corresponding TS packet becomes a predetermined time ta. Here, the fixed time ta is a time required for the digital broadcast receiving apparatus 2 to extract packetized information from the TS. By providing the predetermined time ta, the number of audio frames included in the PES packet can be obtained before the PTS from which the PES packet is restored is extracted in the digital broadcast receiving apparatus.

FIG. 4 is a flowchart showing details of the system encoding process in the system encoding unit 13 in the digital broadcast transmitting apparatus 1.
As shown in the figure, when the packetization information and the PES packet are input from the packetization unit 12 (S401, S402), the system encoding unit 13 generates section data from the packetization information (S403), and further section data Are converted into TS packets (S404). This packetization information indicates the number of AAC audio frames stored in the corresponding PES packet output from the packetizing unit 12. Since the PES packet has a variable length, the number of frames can be arbitrarily set for each PES packet. The size of the AAC audio frame also varies depending on the sampling frequency and the number of samples per frame. The number of samples per frame is typically 1024 samples. The sampling frequency includes 44 kHz and 22 kHz. Here, it is assumed that several frames (about 1 to 10) are stored in one PES packet.

Next, the system encoding unit 13 converts the PES packet input from the packetizing unit 12 into a plurality of TS packets (S405). Since conversion to a TS packet is a known technique, the details are omitted.
Further, the system encoding unit 13 outputs the TS packet of the section data to the modulation unit 14 (S405), and when a certain time ta has elapsed (S406), a plurality of TS packets converted from the PES packet corresponding to the section data Are sequentially output to the modulation unit 14 (S407, S408). Thereby, the TS packet of the section data and the TS packet converted from the PES packet are multiplexed on the TS. At this time, a certain time ta is secured from the transmission of the TS packet of the section data to the transmission of the TS packet converted from the PES packet. This fixed time ta is the time required for extracting packetized information from the TS in the digital broadcast receiving apparatus 2 as described above. The number of frames can be obtained before the analysis of each PES packet is started in the receiving apparatus.

  FIG. 5 is a flowchart showing details of packet analysis processing in the packet analysis unit 25 in the digital broadcast receiving apparatus 2. In the packet analysis unit 25, the PES packet is input from the system decoding unit 23 to the encoded signal extraction unit 251 and the reproduction time information extraction unit 253. The packetization information is input to the error detection / correction unit 253 before the predetermined time ta.

  The error detection correction unit 253 holds the PTS (PTS_old) added to the previous PES packet, and when packetization information is input (S501), the number of frames indicated by the packetization information ( The reproduction time length tf of the PES packet is calculated based on the number of audio frames included in the PES packet after a certain time ta (S502). In the case of an AAC audio frame, one frame time is easily calculated according to the sampling frequency since one frame is 1024 samples. The reproduction time length tf is obtained by multiplying one frame time by the number of frames.

Further, the error detection correction unit 253 adds the PTS_old and the playback time length tf to calculate a predicted PTS, that is, PTS_ref as a predicted value of the playback time (S503).
On the other hand, the reproduction time information extraction unit 252 analyzes the header of the PES packet input after a certain time ta from the input of the packetization information, extracts the PTS that is the reproduction time information, and outputs the PTS_now to the error detection correction unit 253. To do. At this time, if the PTS is not included, the reproduction time information extraction unit 252 outputs an invalid value, for example, as a NULL signal or PTS, and outputs information notifying that the PTS is not included.

Thereafter, the error detection correction unit 253 determines whether there is PTS_now depending on whether there is a notification that the PTS is not included (S504).
When there is PTS_now, the error detection correction unit 253 acquires the value of the PTS_now (S505), and determines whether the difference between PTS_now and PTS_ref is within the error range Te (S506). As a result of the determination, if the difference is within the error range, the error detection correction unit 253 determines that PTS_now is correct, outputs PTS_now to the decoding unit 26 as the PTS of the packet (S507), and sets PTS_old to PTS_now. The value is updated (S508). As a result of the determination, if the difference is larger than the error range, the error detection / correction unit 253 determines that PTS_now is incorrect, outputs PTS_ref to the decoding unit 26 as the PTS of the packet (S507), and PTS_old. Update to the value of PTS_ref (S508). If it is determined in S504 that there is no PTS_now, PTS_ref is output to the decoding unit 26 as the PTS of the packet, and PTS_old is updated to the value of PTS_ref.

  As described above, the error detection / correction unit 253 determines whether the PTS extracted by the reproduction time information extraction unit 252 is correct or not. If it is determined to be an error, the error detection / correction unit 253 predicts the correct PTS, Instead, the predicted PTS_ref is output. Similarly, when the PTS is not included in the PES packet header, the predicted PTS_ref is output in the same manner.

  As described above, the digital broadcast transmitting apparatus 1 according to the present embodiment is different from the digital broadcast receiving apparatus 2 in the PES packet that is asynchronous with the frame structure of the AAC bitstream that is a reproduction unit, and the reproduction in the PES packet. It is possible to transmit packetized information (the number of frames in the above example) regarding the time length. As a result, the digital broadcast receiving apparatus 2 can obtain packetization information, for example, that one PES packet is composed of four AAC frames before analyzing the PES packet. By determining whether or not the PTS that is the playback time information that has been reproduced is a value advanced by four frame times of the AAC bitstream compared to the previous PTS, it is added to the current PES packet. The correctness / incorrectness of the PTS can be determined. Furthermore, even if it is wrong or no PTS is added to the current PES packet, it can be supplemented with a value advanced by, for example, 4 frame times.

  In the above-described embodiment, the configuration in which packetization information in one section format is multiplexed in advance with respect to one PES packet (see FIG. 3D), but 1 for a plurality of PES packets. A configuration may be adopted in which packetization information in one section format is multiplexed in advance. An example in that case is shown in FIG. In the figure, T11 to T1n are TS packets converted from the PES packet 1, and T31 to T3n are TS packets converted from the PES packet 3. T11 to T3n correspond to three PES packets, and each has Na (for example, four) frames. T41 to T5n correspond to two PES packets, and each has Nb (for example, three) frames. In this case, the section-format TS packet S1 has packetization information indicating Na, and indicates the number of frames of the following three PES packets. The TS packet S1 is valid until the next section type TS packet (section type TS packet indicated as Nb in the figure) appears. Similarly, a section-type TS packet denoted as Nb indicates the number of frames of the following two PES packets.

  In FIG. 6, when the number of frames of the PES packet is the same as the number of frames of the immediately preceding PES packet, the section format TS packet including packetization information is omitted. In this case, when the current packetization information has the same content as the packetization information corresponding to the PES packet sent to the modulation unit 14 immediately before, the system encoding unit 13 sends a section-format TS packet including the packetization information. May be omitted. Thereby, the transmission amount can be further reduced.

  Furthermore, even if the current packetization information has the same content as the packetization information corresponding to the PES packet sent to the modulation unit 14 immediately before, the system encoding unit 13 includes a section-format TS packet including the previous packetization information. When a certain time interval has been exceeded since the transmission of the signal, it may be configured to transmit to the modulation unit 14 without omitting the multiplexing. In this way, it can be ensured that the digital broadcast receiving apparatus that has started reproduction in the middle of the broadcast can perform correct / incorrect determination and correction within a certain time interval from the start of reproduction.

Further, the section-format TS packet including packetization information may have the number of frames Na as packetization information as shown in FIG. 7A, or may be the data length in the PES packet. . The packetization information may be data indicating the reproduction time length, and may be the number of samples and the sampling frequency.
Further, as shown in FIG. 7A, a section-format TS packet including packetization information may have the number of subsequent PES packets Nb to which the frame number Na applies in addition to the number of frames Na. Good.

  In this embodiment, audio data is to be encoded and decoded. However, the present invention is used if data that needs to be designated for processing on the receiving side is to be transmitted. The same effect can be obtained. A typical example is a case where video data is encoded and transmitted. When the video data is encoded such that a plurality of frames are packetized instead of one frame per packet, the same effect can be obtained by using the present invention.

  Also, there may be a plurality of transmission data to be subjected to correction of the reproduction time information. That is, the video data and the audio data are multiplexed and transmitted, and the reproduction time information of each data is corrected by using the present invention, whereby the reproduction time of both the video and the audio can be corrected. . Therefore, these are not excluded from the scope of the present invention.

  The present invention is suitable for digital broadcasting in which information such as audio, moving images, or characters is transmitted in digital form, and in particular, a digital broadcast transmitting apparatus that performs digital broadcasting via a transmission path including ground waves and satellite waves, and a set top. Suitable for digital broadcast receivers such as boxes, portable radios, car radios.

It is a block diagram which shows the structure of the digital broadcast transmission / reception system in embodiment of this invention. It is a functional block diagram which shows the detailed structure of a packet analysis part. (A)-(d) It is explanatory drawing of the PES packet, TS packet, section, and TS which are produced | generated in the digital broadcast transmitter 1. FIG. It is a flowchart which shows the detail of the system encoding process in the system encoding part 13 in a digital broadcast transmitter. It is a flowchart which shows the detail of the packet analysis process in the packet analysis part 25 in a digital broadcast receiver. It is explanatory drawing of TS which multiplexes beforehand the packetization information of one section format with respect to several PES packets. (A) (b) It is a figure which shows the other structural example of the TS packet of a section format.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Digital broadcast transmitter 2 Digital broadcast receiver 11 Encoding part 12 Packetization part 13 System encoding part 14 Modulation part 15 Transmission antenna 21 Reception antenna 22 Demodulation part 23 System decoding part 24 Section analysis part 25 Packet analysis part 26 Decoding part 27 System Clock generation unit 251 Encoded signal extraction unit 252 Playback time information extraction unit 253 Error detection / correction unit

Claims (10)

Separating means for separating a packet including data from packetized information regarding the data amount of the data from received multiplexed data;
Determination means for determining whether the reproduction time set in the packet is correct or not based on the packetization information separated by the separation means;
Correction means for correcting the reproduction time of the data based on the packetization information when the determination means determines that there is an error;
A digital broadcast receiving apparatus comprising: The packetization information indicates any of the number of frames of data in the packet, the size of the data in the packet, and the reproduction time length of the data in the packet.
The digital broadcast receiver according to claim 1. The determination means determines whether the reproduction time set in the packet is correct or not by using packetization information received a predetermined time or more before the packet.
The digital broadcast receiver according to claim 2. If the packetization information is not received a certain time before the packet, the determination unit determines whether the reproduction time set in the packet is correct using the packetization information received immediately before
The digital broadcast receiver according to claim 3. The determination means includes holding means for holding time data indicating the reproduction time of the immediately preceding packet;
A calculation means for calculating the reproduction time length of the data in the current packet from the packetization information;
A predicting means for predicting a predicted playback time from the playback time of the immediately preceding packet and the calculated playback time length;
Judging means for judging whether the reproduction time set in the current packet is correct or not according to the difference between the reproduction time set in the current packet and the predicted reproduction time;
The digital broadcast receiver according to claim 3, further comprising: The correction means corrects the reproduction time of the current packet to the predicted reproduction time when the determination means determines that there is an error.
The digital broadcast receiving apparatus according to claim 5. The correction means further sets the predicted reproduction time as the reproduction time of the current packet when the reproduction time is not set in the current packet.
The digital broadcast receiving apparatus according to claim 6. A digital broadcast system including a digital broadcast transmitter and a digital broadcast receiver,
The digital broadcast transmission device includes:
Packet generation means for generating a packet including data;
Packetization information generating means for generating packetization information related to the amount of data included in the packet;
Multiplexing means for multiplexing the packet and the packetization information and generating multiplexed data;
Transmission means for transmitting the multiplexed data,
The digital broadcast receiving apparatus includes:
Separating means for separating a packet including data from packetized information regarding the data amount of the data from received multiplexed data;
A determination unit that determines whether the reproduction time set in the packet is correct based on the packetization information separated by the separation unit;
And a correction unit that corrects the reproduction time of the data based on the packetization information when the determination unit determines an error.
A digital broadcasting system characterized by this. A separation step of separating, from the received multiplexed data, a packet including data and packetization information relating to a data amount of the data;
A determination step of determining whether the reproduction time set in the packet is correct or not based on the packetization information separated in the separation step;
A correction step of correcting the reproduction time of the data based on the packetization information when it is determined that there is an error in the determination step;
A digital broadcast receiving method comprising: A separation step of separating, from the received multiplexed data, a packet including data and packetization information relating to a data amount of the data;
A determination step of determining whether the reproduction time set in the packet is correct or not based on the packetization information separated in the separation step;
A correction step of correcting the reproduction time of the data based on the packetization information when it is determined that there is an error in the determination step;
Is executed by a computer in the digital broadcast receiving apparatus.

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