JP2001326888A - Digital broadcast receiving system - Google Patents

Abstract

(57) [Summary] [Problem] A digital broadcast includes a plurality of information tables, and information necessary for recording / reproduction scattered in various information tables is easily extracted, and recording / reproduction is performed even when operation is discontinuous. The operation of devices and receivers, especially the generation of system clocks, should not fail. SOLUTION: Information necessary for recording and reproduction, particularly information indicating the bit rate of a program of a digital broadcast signal, broadcast start date and time, broadcast time length, program name, channel name to be recorded, and the type of each stream of the digital broadcast signal Is extracted. Then, the information is multiplexed with a digital television signal as a recording / playback information table in a predetermined table format, together with information on a discontinuity point indicating that a discontinuity has occurred in the signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to a digital broadcast receiving system having a receiver and a recording / reproducing device, and more particularly to a digital broadcast receiving system capable of minimizing a failure when a signal is interrupted.

[0002]

2. Description of the Related Art FIGS. 5 and 6 are block diagrams showing the configuration of a conventional digital broadcast receiving system. In the figure, a digital broadcast receiving system includes a receiver 2 and a recording / reproducing device 3.
, And a monitor 4 is connected to the receiver 2. The receiver 2 is an external digital broadcast, for example, an MPE
The image signal compressed by G2 is received, and FIG.
As shown in (1), a reception demodulation unit 11, a packet filter 12, a controller 13, an information table extractor 14, a program selection information acquisition unit 15, a system clock generator 16, a changeover switch 17, a demultiplexer 18, Audio decoder 19, video decoder 20, text decoder 21, and digital interface 22
have.

On the other hand, a recording / reproducing apparatus 3 is for recording and reproducing an inputted digital broadcast signal. As shown in FIG. 6, a digital interface 3 connected to a receiver 2 is provided.
1, information table extractor 32, system clock generator 33, controller 34, deck unit 35, buffer 36
It is comprised including.

[0004] The operation of the digital broadcast receiving system will be described below. The receiver 2 first demodulates the received digital broadcast signal by the reception demodulation unit 11. The system clock generator 16 generates a system clock 27 MHz of the receiver with reference to a clock recovery reference signal called PCR included in the MPEG2 transport packet. The information table extractor 14 is an information table relating to a network multiplexed and transmitted in a digital broadcast signal according to the MPEG2 system.
(Network Information Table), and an information table for each program of each channel, that is, a PAT (Program Association Table), which is information on the entire transmitted program,
PMT which is information on the packet configuration etc. for each program
(ProgramMapping Table) and EIT (Event Information Table), which is detailed information of each program, are extracted from the digital broadcast signal. The controller 13 thus informs the user of information on the program in the signal from the table information. The information is presented to the user by the monitor 4.

When the user designates a specific program, the controller 13 switches the changeover switch 17 to the receiving / demodulating section 11, and instructs the demultiplexer 18 to select a packet of the digital broadcast signal based on the table information. The demultiplexer 18 outputs the bit stream of the audio data to the audio decoder 19 while disassembling the packet format according to the instruction.
The bit stream of the video data is sent to the video decoder 20,
The bit stream of the text data is sent to the text decoder 21. Each of the decoders 19 to 21 decodes the data and reproduces the program on the monitor 4.

As one method of realizing recording, there is a method in which a packet of a selected program is designated by a controller 13, a designated packet is selected by a packet filter 12, and output to a digital interface 22. When the user selects a program to be recorded, for example, by a remote control device based on the information on the program, the controller 13 inputs this selection input via the program selection information acquisition unit 15. The controller 13 specifies a packet of the program to be recorded according to the table information, and the packet filter 12 selects the specified packet. Then, the digital television signal from which the packet has been selected is transmitted via the digital interface 22 to the recording / reproducing device 3.
Is output to

When the recording / reproducing apparatus 3 receives a digital television signal via the digital interface 31, the information table extractor 32 extracts an information table from the signal. The system clock generator 33 refers to the PCR included in the transport packet of MPEG2 from the extracted information table, and generates a system clock 27 MHz of the recording / reproducing device 3. Then, the data is recorded on the recording medium by the deck unit 35.

On the other hand, when reproducing a program recorded in the recording / reproducing apparatus 3, the user inputs a reproduction to the controller 34. Then, the recording / reproducing apparatus 3 reproduces the digital signal of the program from the recording medium by the deck unit 35, performs operations such as demodulation and error correction, and performs the digital interface 31.
Output to

The receiver 2 has a digital interface 22
When the digital television signal is received through the information table, the information table extractor 14 extracts the information table.
The system clock generator 16 obtains M
The system clock of the receiver 2 is generated at 27 MHz with reference to the PCR included in the PEG2 transport packet. Further, the controller 13 switches the changeover switch 17 to the digital interface 22 side, and supplies the reproduced television signal to the demultiplexer 18. The demultiplexer 18 separates the signals and outputs the signals to the decoders 19 to 2.
1 for decoding and reproduction and display on the monitor 4.

[0010]

However, the value of the PCR becomes discontinuous due to the channel switching or the program switching of the receiver, and the recording / reproducing apparatus also becomes discontinuous when, for example, switching from normal reproduction to high-speed reproduction is performed. . When such discontinuity occurs, the operation of the recording / reproducing device and the receiver, particularly, the operation of generating the system clock has a defect.

In view of the foregoing, the present invention multiplexes information about discontinuous points in an information table, thereby obtaining a system for minimizing the operation of the recording / reproducing apparatus and the receiver, particularly the failure during generation of a system clock. The purpose is to:

[0012]

According to a first aspect of the present invention, there is provided a receiver for receiving a digital broadcast signal, and at least a part of the digital broadcast signal connected to the receiver and received by the receiver. A recording / reproducing apparatus that inputs, records, and reproduces the recorded digital broadcast signal and outputs the signal to the receiver.In the digital broadcast receiving system, the receiver includes a digital broadcast signal output to the recording / reproducing apparatus. A discontinuity information generating means for detecting the occurrence of the discontinuity and generating discontinuity information for indicating a place where the discontinuity has occurred, and multiplexing the digital broadcast signal as table information having a predetermined format. Information table rewriting means for outputting the multiplexed digital broadcast signal to the recording / reproducing apparatus.

According to a second aspect of the present invention, in the digital broadcast receiving system according to the first aspect, the discontinuous information generating means includes a discontinuous information indicating that a channel of a digital broadcast to be received or a program to be output has been switched. Is generated.

According to a third aspect of the present invention, a receiver for receiving a digital broadcast signal, and at least a part of the digital broadcast signal connected to the receiver and received by the receiver are input and recorded, A recording / reproducing apparatus for reproducing a recorded digital broadcast signal and outputting the signal to the receiver, wherein the recording / reproducing apparatus has caused a discontinuity in the reproduced signal when reproducing the recorded signal. And discontinuous information rewriting means for multiplexing the discontinuous information for indicating the place where the discontinuity has occurred in the digital broadcast signal as table information having a predetermined format. The signal is output to the receiver.

According to a fourth aspect of the present invention, in the digital broadcast receiving system of the third aspect, the discontinuous information rewriting means does not change the reproduction speed when the reproduction speed from the recording medium is changed during the reproduction. The information is multiplexed as continuous information in the digital broadcast signal and output to the receiver.

According to a fifth aspect of the present invention, a receiver for receiving a digital broadcast signal, and at least a part of the digital broadcast signal connected to the receiver and received by the receiver are recorded and recorded. A recording / reproducing apparatus that reproduces a digital broadcast signal and outputs the digital broadcast signal to the receiver, wherein the receiver includes:
When a discontinuity occurs in the digital broadcast signal output to the recording / reproducing apparatus, the discontinuous information indicating a location where the discontinuity occurs is transmitted, and the recording / reproducing apparatus receives the discontinuous information. Is recorded together with the digital broadcast signal in a predetermined format capable of indicating a location where the discontinuity has occurred.

According to a sixth aspect of the present invention, a receiver for receiving a digital broadcast signal, and at least a part of the digital broadcast signal connected to the receiver and received by the receiver are input and recorded, A recording / reproducing apparatus that reproduces a recorded digital broadcast signal and outputs the signal to the receiver, a digital broadcast receiving system comprising:
When the digital broadcast signal reproduced from the recording / reproducing apparatus includes discontinuity information indicating a location where the discontinuity has occurred, a process is performed on the digital broadcast signal to reduce a failure due to the discontinuity. It has a controller.

According to a seventh aspect of the present invention, in the digital broadcast receiving system according to the sixth aspect, the controller comprises:
When discontinuity information indicating a place where discontinuity has occurred in the digital broadcast signal output from the recording / reproducing apparatus is input, the digital broadcast signal is reloaded with a clock reference signal, and a part of the information table is reloaded. Is performed.

According to an eighth aspect of the present invention, there is provided a receiver for receiving a digital broadcast signal, and inputting and recording at least a part of the digital broadcast signal which is connected to the receiver and received by the receiver, A recording / reproducing apparatus for reproducing a recorded digital broadcast signal and outputting the signal to the receiver, wherein rate information on the digital broadcast signal output from the receiver to the recording / reproducing apparatus or the digital broadcast When the information about the rate of each stream is not output, the recording device records at the maximum recordable rate.

[0020]

1 and 2 are block diagrams showing the configuration of a digital broadcast receiving system according to an embodiment of the present invention. In this embodiment, the same parts as those of the above-described conventional example are denoted by the same reference numerals. The digital broadcast receiving system includes a receiver 2 and a recording / reproducing device 3, as in the conventional example, and a monitor 4 is connected to the receiver 2. As shown in FIG. 1, the receiver 2 includes a reception demodulation unit 11, a packet filter 12, a controller 23, and an information table extractor 1.
4, program selection information acquisition unit 15, system clock generator 16, changeover switch 17, demultiplexer 18, audio decoder 19, video decoder 20, text decoder 2
1, having a digital interface 22 is the same as the conventional example. In this embodiment, in addition to this, the information table rewriter 24 that rewrites the information table obtained from the packet filter 12 and the demodulation signal obtained from the reception demodulation unit 11 are detected to be discontinuous, and the discontinuity information is detected. , And a recording / reproducing information table generator 26 for generating a recording / reproducing information table described later.

On the other hand, the recording / reproducing device 3 comprises a digital interface 31, an information table extractor 3 as shown in FIG.
2, a system clock generator 33, a deck unit 35, and a buffer 36. In addition, a PCR rewrite unit 37 for rewriting PCR, a discontinuous information rewrite unit 38 for rewriting discontinuous information, and a discontinuous information Discontinuous information detector 3 to detect
9, a controller 40 and a display 41 for displaying the operation state thereof.

The operation of the digital broadcast receiving system will be described below. The receiver 2 first demodulates the received digital broadcast signal by the reception demodulation unit 11. Information table extractor 14
Is an information table NIT (Network Information Table) relating to a network multiplexed and transmitted in a digital broadcast signal according to the MPEG2 system, and an information table relating to each channel program, that is, information of the entire transmitted program. A PAT (Program Associat
ion Table), PMT (Program Mapping Table) which is information on the packet configuration of each program, etc., and EIT (Event Information Table) which is detailed information of each program
Is extracted from the digital broadcast signal. FIG. 3 shows an example of the extracted information table. The system clock generator 16 selects the MPE from the extracted information table.
The system clock 27 MHz used in the receiver 2 is generated by referring to a clock recovery reference signal called PCR included in the G2 transport packet.

The controller 23 extracts information on the program in the signal from the extracted information table, and notifies the user. The subsequent process of directly demodulating the received digital broadcast signal and displaying the demodulated signal on the monitor 4 is the same as that of the conventional example, and the description is omitted.

Next, the operation at the time of recording will be described. The user selects a program to be recorded, and the program selection information acquiring unit 15
When the program name or the like is input, the controller 23 specifies the packet of the program to be recorded to the packet filter 12 by the table information. The packet filter 12 selects a specified packet and outputs it to the digital interface 22. Further, the controller 23 includes the information table extractor 1
4 among the information in each information table extracted by
In particular, the bit rate of the program of the digital broadcast signal recorded from the descriptor in the PMT or EIT, the broadcast start date and time,
The broadcast time length, the name of the program, and the name of the channel to be recorded are extracted. Information indicating the type of each stream of the digital broadcast signal to be recorded from the descriptor of the PMT or NIT;
For example, NIT service_list_descriptor or PMT
Extract data_component_descriptor.

The recording / reproducing information table generator 26 converts the descriptor and information extracted by the controller 23 into MP
EG2 transport packet format and predetermined MPE
A recording / reproducing information table is generated in a table format having a table ID of G2. FIG. 4 shows information tables A to 3 in FIG.
9 shows an example of a recording / reproduction information table in which information extracted from C is collected. The information table for recording and reproduction generated in this way is rewritten by the information table rewriter 24 and sent out to the recording and reproducing apparatus 3 via the digital interface 22 together with the digital broadcast signal.

During reception of a digital television signal for recording, discontinuity such as generation of a system clock may occur due to an operation such as channel switching or program switching in the receiver 2. Discontinuity information generator 25
Detects such discontinuity and generates discontinuity information.
Then, the discontinuous information is input to the information table rewriter 24 and multiplexed into the recording / reproducing table as shown in FIG.

The information table rewriter 24 replaces the extracted information table with the recording / reproduction information table that has generated the NIT. Also, PAT and PMT are rewritten so that only information on the program and packet selected by the packet filter is described.

If there is an interval for transport packets to be inserted without collision in a place other than the NIT, especially near the above-mentioned discontinuity, a recording / reproducing table may be inserted in that part. . However, if a large number of recording / reproducing tables are separately inserted, the rate required for recording increases, so that caution is required in comparison with the rate of the recording medium. The digital television signal subjected to the operation of rewriting the table for packet selection and recording / reproduction, PAT, PMT, etc.
Recording / reproducing device 3 via digital interface 22
Is output to

When the recording / reproducing apparatus 3 receives the digital television signal from the digital interface 31, the information table extractor 32 extracts the recording / reproducing information table, the PAT, and the information table including the PMT relating to the output program.

From the extracted information table, the controller 40 determines the program bit rate, broadcast start date and time, broadcast time length, program name, and program name of the received digital broadcast signal.
Extract the name of the channel to be recorded.

The system clock generator 33 is an MPEG2
The system clock 27 MHz of the recording / reproducing apparatus 3 is generated with reference to the PCR included in the transport packet of the above. The discontinuity information detector 39 monitors whether or not discontinuity information is included in the information table of the digital video signal,
If discontinuity information is included in the information table,
Immediately inform the information table extractor 32, the system clock generator 33, and the controller 40 to reload the PCR, PAT, and PMT, thereby minimizing the failure due to clock discontinuity.

The controller 40 sets the recording bit rate of the recording / reproducing device 3 from the information in the information table, and performs operations such as error correction and modulation by the deck unit 35 and records the data on the recording medium.

Here, if there is no information on bit rate extraction in the information table and the recording bit rate cannot be set, the controller 40 sets the mode to the maximum recording bit rate of the recording / reproducing apparatus 3 and records. At this time, the occupancy of the buffer 36 is monitored, and when the rate of the received signal exceeds the recording rate and overflows from the buffer 36, the user is informed.

On the other hand, at the time of reproduction, the recording / reproducing apparatus 3 demodulates the reproduction signal from the recording medium by the deck unit 35, performs an operation such as error correction, and outputs the signal to the digital interface 31. At this time, if the operation mode is changed, for example, from normal playback to high-speed playback, rewind playback, slow playback, etc., the PCR is rewritten to the correct value by the PCR rewriter 37 and recorded by the discontinuous information rewriter 38. Information indicating discontinuity is added to the reproduction information table.

The receiver 2 has a digital interface 22
Receiving a digital television signal from the information table extractor 14, the information table extractor 14
An information table including T and a PMT relating to the output program is extracted.

The controller 23 determines the bit rate of the program of the received digital broadcast signal from the information table.
The broadcast start date and time, broadcast time length, program name, and channel name to be reproduced are extracted. Further, the changeover switch 17 is switched to the digital interface 22 side.

The system clock generator 16 is an MPEG2
The system clock 27 MHz of the receiver 2 is generated with reference to the PCR included in the transport packet of (2). If discontinuity information is included in the information table, the PCR, PAT, and PMT are immediately reloaded, thereby preventing a failure due to clock discontinuity from being minimized.
Alternatively, the system clock generation by the PCR may be stopped, and the operation may be switched to generate and operate the self-running clock of 27 MHz. If it is known in advance that a self-running clock is to be generated, there is no particular need to correctly change the PCR at the time of reproduction output of the recording / reproducing device 3.

The controller 23 separates the received television signal by the demultiplexer 18 on the basis of the extracted information, particularly the type of each stream.
9 to 21 for decoding and reproduction. Particularly, in the reproduction of a data signal stream such as a text, separation reproduction can be easily performed by having the type information of each stream.

[0039]

As described above, according to the present invention, when a digital television signal is recorded, information relating to discontinuity is multiplexed in an information table, whereby the operation of a recording / reproducing apparatus and a receiver, particularly, a system The effect that the failure at the time of clock generation can be minimized is obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a receiver of a digital broadcast receiving system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a recording / reproducing device of the digital broadcast receiving system according to one embodiment of the present invention.

FIG. 3 is a diagram illustrating an example of an information table included in a received television signal according to the embodiment;

FIG. 4 is a diagram illustrating an example of a recording / reproduction information table according to the embodiment;

FIG. 5 is a block diagram showing a configuration of a receiver of a conventional digital broadcast receiving system.

FIG. 6 is a block diagram showing a configuration of a recording / reproducing device of a conventional digital broadcast receiving system.

[Explanation of symbols]

 2 Receiver 3 Recording / reproducing device 4 Monitor 11 Reception / demodulation unit 12 Packet filter 13 Controller 14 Information table extractor 15 Program selection information acquisition unit 16 System clock generator 17 Changeover switch 18 Demultiplexer 19 Audio decoder 20 Video decoder 21 Text decoder 22 Digital interface 23 Controller 24 Information table rewriter 25 Discontinuous information generator 26 Recording / reproduction information table generator 31 Digital interface 32 Information table extractor 33 System clock generator 34 Controller 35 Deck unit 36 Buffer 37 PCR rewriter 38 Discontinuity Information rewriter 39 Discontinuous information detector 40 Controller 41 Display

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) H04N 5/92 H04N 5/92 H 7/08 7/08 Z 7/081

Claims (8)

[Claims] 1. A receiver for receiving a digital broadcast signal, and at least a part of the digital broadcast signal connected to the receiver and received by the receiver is input and recorded, and the recorded digital broadcast signal is reproduced. And a recording / reproducing device that outputs the signal to the receiver. The receiver detects that a discontinuity has occurred in a digital broadcast signal output to the recording / reproducing device, and detects the discontinuity. Having discontinuous information generating means for generating discontinuous information for indicating the location where the error occurred, and information table rewriting means for multiplexing the digital broadcast signal as table information having a predetermined format,
A digital broadcast receiving system for outputting the multiplexed digital broadcast signal to the recording / reproducing device. 2. The digital system according to claim 1, wherein said discontinuity information generating means generates discontinuity information indicating that a channel of a digital broadcast to be received or a program to be output has been switched. Broadcast receiving system. 3. A receiver for receiving a digital broadcast signal, at least a part of the digital broadcast signal connected to the receiver and received by the receiver, recording the digital broadcast signal, and reproducing the recorded digital broadcast signal. And a recording / reproducing device that outputs the signal to the receiver. The recording / reproducing device detects that a discontinuity of the reproduced signal has occurred when reproducing the recorded signal, and Discontinuous information rewriting means for multiplexing discontinuous information for indicating a place where continuation has occurred as table information having a predetermined format into the digital broadcast signal, and outputting the digital broadcast signal to the receiver A digital broadcast receiving system characterized by the following. 4. The discontinuous information rewriting means multiplexes the switching of the reproducing speed as discontinuous information into the digital broadcast signal and outputs the multiplexed signal to the receiver when the reproducing speed from the recording medium is switched during the reproducing. The digital broadcast receiving system according to claim 3, wherein: 5. A receiver for receiving a digital broadcast signal,
A recording / reproducing apparatus connected to the receiver, for recording at least a part of the digital broadcast signal received by the receiver, reproducing the recorded digital broadcast signal, and outputting the reproduced digital broadcast signal to the receiver. In the receiving system, the receiver, when a discontinuity occurs in a digital broadcast signal output to the recording / reproducing device, transmits discontinuity information indicating a location where the discontinuity has occurred, and the recording A digital transmission / reception system, wherein the playback device records the received discontinuity information together with the digital broadcast signal in a predetermined format capable of indicating a location where the discontinuity has occurred. 6. A receiver for receiving a digital broadcast signal, inputting and recording at least a part of the digital broadcast signal connected to the receiver and received by the receiver, and reproducing the recorded digital broadcast signal And a recording / reproducing device that outputs the signal to the receiver. The receiver further comprises: a receiver for indicating a location where a discontinuity occurs in the digital broadcast signal reproduced from the recording / reproducing device. A digital broadcast receiving system, comprising: a controller for performing processing for reducing breakage of the digital broadcast signal due to discontinuity when continuous information is included. 7. A controller for reloading a clock reference signal to the digital broadcast signal when the controller inputs discontinuity information indicating a location where the discontinuity has occurred in the digital broadcast signal output from the recording / reproducing apparatus. And reloading a part of the information table.
The digital broadcast receiving system according to the above. 8. A receiver for receiving a digital broadcast signal, and receiving and recording at least a part of the digital broadcast signal connected to the receiver and receiving the digital broadcast signal, and reproducing the recorded digital broadcast signal. And a recording / reproducing apparatus for outputting to the receiver the rate information relating to the digital broadcast signal output from the receiver to the recording / reproducing apparatus or the information relating to the rate of each stream during the digital broadcasting. Wherein the recording device records at the maximum recordable rate when the digital broadcast is not output.