JP2002057954A - Digital signal decoder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a digital signal decoder that can decode a signal, on which services are multiplexed, which is reproduced or received. SOLUTION: The digital signal decoder is provided with a selection means that selects a service when the signal includes only one service or selects one of the services on the basis of information described in identification information when the signal includes the services and with a decoding means that decodes the signal of the service selected by the selection means and outputs the decoded signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an apparatus for selecting and decoding a desired signal from a plurality of digital signals, and more particularly to a digital signal decoding apparatus for decoding a signal reproduced from a digital signal recording / reproducing apparatus. .

[0002]

2. Description of the Related Art A digital broadcast receiving method for outputting a received digital broadcast signal from a digital interface and recording the output signal in a recording device is disclosed in Japanese Patent Laid-Open No. 9-247.
No. 616. In this digital broadcast receiving method, a digital signal received and demodulated by a digital broadcast receiving device is output to a recording device via a digital interface and recorded.

[0003]

However, the above publication does not consider the case where a plurality of services (such as broadcast channels) are simultaneously output or recorded / reproduced. Since a digital broadcast signal is usually transmitted by multiplexing signals of a plurality of services, it is possible to output or record / reproduce all services or a plurality of services selected therefrom. However, when a plurality of services are multiplexed, there is a problem that it is not possible to know which service should be decoded at the time of decoding.

An object of the present invention is to provide a digital signal decoding apparatus which can cope with a case where a signal in which a plurality of services are multiplexed is reproduced or inputted.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a digital signal decoding apparatus capable of decoding a digital signal in which a plurality of services and identification information for identifying the services are multiplexed. When there are a plurality of services, there are provided selecting means for selecting one of the plurality of services based on information described in the identification information, and decoding means for decoding a signal of the service selected by the selecting means. Selecting means for selecting a service when there is only one service, displaying a menu for selecting a service on a display device when there are a plurality of services, and selecting a service from the outside based on the menu. And decoding means for decoding the signal of the service selected by the selection means.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram when the digital signal decoding device of the present invention is connected to a recording / reproducing device and a display device. A digital signal decoding device 200 receives a digital broadcast signal and outputs the digital broadcast signal from a digital interface.
01 is a demodulation circuit for demodulating a received digital broadcast signal, 202 is a selection circuit for decoding, 203 is a decoding circuit, 204 is a selection circuit for digital interface output, 205 is an interface circuit, 206 is a control circuit, and 210 is a control circuit. Is a monitor device, 220 is a digital signal recording / reproducing device such as a digital VTR or a digital disk recorder, 230 is a monitor device having a built-in digital interface and decoding circuit, 231 is a selection circuit, 231 is a selection circuit,
32 is a decoding circuit, and 233 is a monitor.

[0007] The digital broadcast signal is a packet data of a compressed digital video signal, digital audio signal, or the like, and a signal of one service or a signal obtained by time-division multiplexing a signal of a plurality of services is transmitted. At the time of receiving a digital broadcast, a received radio wave received by the antenna is input to the demodulation circuit 201 from the input terminal 207. Demodulation circuit 2
In 01, the radio wave of the frequency to be received is demodulated, and the digital broadcast signal is demodulated and output to the selection circuits 202 and 204. The selection circuit 202 selects a digital video signal, digital audio signal, or digital data signal of a service to be received from the digital broadcast signal. The digital video signal and the digital audio signal are output to the decoding circuit 203, converted into an analog video signal and an analog audio signal, and output from the output terminal 208 to the monitor device 210. Note that the decoded video signal or audio signal may be output as a digital signal without being converted into an analog signal. Further, the digital data signal is input to the control circuit 206, and processing such as addition of data information to the video signal, for example, addition of subtitle information, is performed. The selection circuit 204 selects a signal to be output from the digital interface, adds and modifies a signal necessary for output from the interface, and outputs the signal to the interface circuit 205. The interface circuit 205 outputs the signal to the output terminal 2
09 to the digital signal recording device 220 for recording. Also, it outputs to the monitor device 230. Selection circuit 231 and decoding circuit 232 built in monitor device 230
Performs operations similar to those of the selection circuit 202 and the decoding circuit 203 to decode digital video signals and digital audio signals. Although not shown, the control circuit similar to the control circuit 206 can also process digital data signals.

When reproducing a digital signal recorded in the digital recording / reproducing device 220, the digital recording / reproducing device 22
The digital signal reproduced from 0 is input to the selection circuit 202 via the interface circuit 205. And
The same processing as that for receiving the digital broadcast signal is performed and decoding is performed. The decoding may be performed in the monitor device 230.

The digital broadcast signal is not a digital video signal to which a digital audio signal and a digital data signal are added, but a digital video signal to which a digital audio signal is added, or a digital audio signal. It may be a signal to which a digital data signal is added.

The device may be a device in which the digital signal decoding device 200 and the digital signal recording / reproducing device 220 or the monitor device 210 are integrated. Further, the digital signal output device is not limited to a device that outputs a received digital broadcast signal, but may be, for example, a device that outputs a signal reproduced from a recording medium.

FIG. 2 shows the structure of a packet of a digital broadcast signal. One packet has a fixed length, for example, 188 bytes, and includes a 4-byte packet header 306 and 184-byte packet information 307. The digital video signal is arranged in the area of the packet information 307. The packet header 307 includes information such as the type of packet information.

FIG. 3 shows the structure of the packet header 306. Reference numeral 501 denotes a synchronization byte indicating the beginning of a packet;
Is an error display indicating the presence or absence of an error, 503 is a unit start display indicating the start of a unit, 504 is a packet priority indicating the importance of a packet, 505 is a packet ID indicating a type of packet, and 506 is scramble control indicating whether or not scrambling is performed. , 507 are adaptation field controls indicating the presence / absence of additional information and the presence / absence of packet information, and 508 is a cyclic counter that counts up in packet units.

FIG. 4A shows an example of the configuration of a digital broadcast transmission signal. Reference numeral 71 denotes the packet shown in FIG. Usually, information related to a data signal program is added to the video signal and the audio signal, and programs of a plurality of services are time-division multiplexed and transmitted. FIG. 4A shows an example in which programs of three services are multiplexed. V1, V2, and V3 are video signals of each service, A1, A2, and A3 are audio signals of each service, and D1 is a first service. This is a data signal packet. It should be noted that the video, audio or data may be composed of a plurality of video or audio for one service. P0, P1, P2, and P3 are information related to the program. Each packet is assigned a different packet ID 505 so that the contents of the packet can be identified.

P0 is information relating to the entire transmission signal shown in FIG.
It is a program association table for recognizing whether D is allocated. P1, P2, P3
Is a program map table including information for recognizing which packet ID is assigned to a video packet, an audio packet, and the like of the service, copy control information of each signal, and the like. Normally, a fixed value, for example, 0 is assigned to the packet ID in the program association table. The SI is service information such as network information and program guide information for identifying which broadcast.

At the time of reception, the service information is checked, the program association table is used to recognize which packet ID is assigned to the program map table of the program to be received, and then the video packet is checked by the program map table of the program to be received. , Which packet ID is assigned to the voice packet or the like. Then, the video packet and the audio packet are extracted and decoded. At the same time, copy control when outputting from the digital interface is performed. Of course, the number of services to be multiplexed may be other than three services, for example, four services, or other information may be multiplexed.

FIG. 4B shows a case where only the first service information and the program information related thereto are selected from FIG. 4A. FIG. 4 (c) is a partial modification of the packet information from FIG. 4 (b). The information of the program association table is changed to information P0 'of only the program for recording. Further, information related to the program to be recorded is newly generated and added as SI '. When the first service is output from the digital interface, the selection and the change are performed by the selection circuit 204 and output via the interface circuit 205.
Of course, other information may be included and output.

FIG. 5 shows an example of the structure of the program association table P0. Reference numeral 401 denotes overall information indicating what the digital broadcast transmission signal is;
Reference numerals 3 and 404 denote information on each service, and a program map table (P0, P1, P2) indicating the channel number of the service and the information of the service.
It is composed of the packet ID of 2). Note that the stuffing data 405 is inserted into a portion where there is no packet information.

FIG. 6 shows an example of the structure of the program association table P0 'containing only the information of the first service. P0 ′ is obtained by deleting the second service information 403 and the third service information 404 from P0.

FIG. 7 shows a program map table (P
0, P1, P2). The program map table includes information 406 regarding the entire program, video information 407, audio information 408, and data information 409.

Next, a case where a plurality of services are selected will be described. FIG. 8 shows an example in which the first service and the second service are selected. FIG. 9 shows a configuration example of the program association table P0 'at that time. In the program association table P0, information on services is arranged in the order of a first service, a second service, and a third service. The packet P0 ′ may be generated by simply deleting information on the third service in the same order, but by changing the order, the packet P0 ′ can be generated without adding any special information and without changing the default. Service can be set.
For example, when the second service is to be the default service, the second service may be set first, and the first service may be decoded at the time of decoding.
The default service is, for example, the current decoding circuit 203
Defaults to the service decrypted by. Thereby, at the time of reproduction, the same service as the service viewed at the time of recording can be decoded first. That is, during reproduction, the same state as during recording can be obtained. If there is a primary service and a secondary service among multiple services,
The primary service may be the default.

FIG. 10 shows a program association table P0 'when all services are recorded as they are.
This is an example of the configuration. In this case, it is not necessary to select a signal, but the program association table P0
The default service can be designated by changing the order of the services described as shown in FIG. In addition to the default services,
The priority for decoding can be specified.

The specification of the default service is effective not only at the time of recording or at the time of output to a recording device, but also at the time of output to a monitor device or the like.

Next, decoding of a reproduced signal during reproduction will be described. At the time of reproduction, the selection circuit 202 first detects a program association table, and detects a program map table according to the information.
The video signal and the audio signal are extracted based on the information of the program map table, output to the decoding circuit 203, and are decoded.

At this time, if there is only one service, the service may be decrypted. If there are a plurality of services,
You need to select a service to decrypt. The selection method is
There are a method of letting the user make a selection and a method of making an automatic selection.

FIG. 11 shows an example of a menu for selection. FIG. 11 shows that, in the program association table of FIG.
Channel number of 101 and P3 channel number of P
This is an example in the case of 3. If you have multiple services,
Message 411 and service channel number 412
A menu 414 is displayed so that a service to be decoded can be selected by a key of the apparatus or a remote controller (not shown). At this time, by displaying the programs in the order described in the program association table, the priority order of the services can be understood. Furthermore, by selecting the default service in advance, the selection of the default service can be facilitated. Also,
If no selection is made for a certain period of time after the menu is displayed, for example, for 10 seconds, a default service may be automatically selected to start decoding.
Of course, even after the start of decoding, a menu can be displayed to enable reselection.

FIGS. 12 and 13 show another example of a menu for selection. In FIG. 12, menus are displayed in order of channel number. FIG. 13 shows not the channel number but the program name detected from the service information. This makes it easy to determine the contents.

In the case of automatic selection, a default service may be selected and decrypted. At this time, a message or menu is displayed on a part of the screen to recognize that a plurality of services are recorded. , And other services can be selected. The display may be performed only for the first fixed time, for example, only for 10 seconds.

The default service at the time of decryption may be selected from the first one in the program association table, but may be the default, for example, the one with the smallest channel number.

In addition, when there are a plurality of services at the time of decoding, processing at the time of reproduction or input of a reproduction signal is
This is effective when decoding a signal input from another device.

FIG. 14 shows another configuration example of the digital signal decoding apparatus of the present invention. In FIG. 14, a digital signal recording / reproducing device 220 is built in,
4 to the digital signal recording / reproducing device 220 directly. The reproduced signal is directly input to the selection circuit 202.

FIG. 15 shows another configuration example of the digital signal recording / reproducing apparatus. 421 is an encoding circuit, 422 is a selection circuit, and 423 is a decoding circuit. The encoding circuit 421 encodes the analog video signal and the analog audio signal input from the input terminal 424, and
Record at 20. Further, the selection circuit 422 and the decoding circuit 4
Reference numeral 23 decodes the reproduced signal reproduced by the digital signal recording / reproducing device 220 into an analog video signal and an analog audio signal and outputs the decoded signal from an output terminal 425. That is, in addition to the digital signal input from the digital interface, an analog video signal and an analog audio signal can be encoded and recorded, and a reproduced signal is decoded and output to a monitor or the like as an analog video signal and an analog audio signal. It is also possible. When there are multiple services at the time of decoding, the process at the time of decoding in the digital signal recording / reproducing device
It is equally applicable.

[0032]

According to the present invention, when decoding an input or reproduced signal, when one service is selected, the service is selected, and when there are a plurality of services, the service is selected based on the information described in the identification information. Alternatively, by selecting and decoding one of a plurality of services based on a menu, an optimum service can be selected and decoded. Also,
When there are a plurality of services, a message or a menu is displayed, so that the presence of a plurality of services can be easily recognized.

[Brief description of the drawings]

FIG. 1 is a configuration diagram when a digital signal decoding device according to an embodiment of the present invention is connected to a recording device and a display device.

FIG. 2 is a configuration diagram of a packet of a digital video compression signal.

FIG. 3 is a configuration diagram of a packet header.

FIG. 4 is a configuration diagram of a digital broadcast transmission signal and a signal selected from the transmission signal.

FIG. 5 is a configuration diagram of a program association table.

FIG. 6 is another configuration diagram of the program association table.

FIG. 7 is a configuration diagram of a program map table.

FIG. 8 is another configuration diagram of a digital broadcast transmission signal and a signal selected from the transmission signal.

FIG. 9 is another configuration diagram of the program association table.

FIG. 10 is another configuration diagram of the program association table.

FIG. 11 is a configuration diagram of a selection menu.

FIG. 12 is another configuration diagram of a selection menu.

FIG. 13 is another configuration diagram of a selection menu.

FIG. 14 is a configuration diagram of a digital signal decoding device according to another embodiment of the present invention.

FIG. 15 is a configuration diagram of a digital signal recording / reproducing device.

[Explanation of symbols]

71: packet, 200: digital signal decoding device, 20
1 demodulation circuit, 202 selection circuit, 203 decoding circuit,
204: selection circuit, 205: interface circuit, 2
06 control circuit, 210 monitor device, 220 digital signal recording / reproducing device, 230 monitor device, 231 selection circuit, 232 decoding circuit, 233 monitor, 306
Packet header, 307: packet information, 401: overall information, 402: service information, 403: service information,
404: service information, 406: entire program information,
407: video information, 408: audio information, 409: data information, 411: message, 412: channel number,
413: channel number, 414: channel number, 4
21: encoding circuit, 422: selection circuit, 423: decoding circuit, 505: packet ID

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Claims (12)

[Claims] 1. A digital signal decoding apparatus capable of decoding a digital signal in which a plurality of services and identification information for identifying the services are multiplexed, selects the service when there is one service, and selects the service when there are a plurality of services. A digital device comprising: selecting means for selecting one of a plurality of services based on information described in the identification information; and decoding means for decoding a signal of the service selected by the selecting means. Signal decoding device. 2. The digital signal decoding apparatus according to claim 1, wherein said multiplexed digital signal is a signal reproduced from a recording medium. 3. The digital signal decoding apparatus according to claim 1, wherein said selecting means selects the first service described in said identification information when there are a plurality of services. 4. The apparatus according to claim 1, wherein said selecting means selects a service having an earliest identification number among services described in said identification information when there are a plurality of services. Digital signal decoding device. 5. The digital signal decoding apparatus according to claim 1, wherein when there are a plurality of services, a message indicating that there are a plurality of services is displayed on a display device. 6. The digital signal decoding apparatus according to claim 1, wherein a menu for selecting a service is displayed on a display device when a plurality of services are provided. 7. A digital signal decoding device capable of decoding a digital signal in which a plurality of services and identification information for identifying the services are multiplexed, wherein when one service is provided, the service is selected. Selecting means for displaying a menu for selecting a service on a display device, and externally selecting a service based on the menu;
A digital signal decoding device comprising decoding means for decoding a signal of a service selected by said selection means. 8. The digital signal decoding apparatus according to claim 7, wherein said multiplexed digital signal is a signal reproduced from a recording medium. 9. The digital signal decoding apparatus according to claim 7, wherein when a plurality of services are not selected from outside, a predetermined service is selected according to the identification information. 10. The digital signal decoding apparatus according to claim 7, wherein said menu is an identification number of a service described in said identification information. 11. The digital signal decoding apparatus according to claim 7, wherein said menu is a program name of a service. 12. The digital signal decoding apparatus according to claim 7, wherein when there are a plurality of services, a message indicating that there are a plurality of services is displayed on a display device.