KR20060020784A - Method for information processing of digital satellite broadcasting receiver - Google Patents

Abstract

According to the present invention, when a PSI / SI is extracted and decoded by demultiplexing a transport stream in a digital satellite broadcasting receiver, in the case of a repeated PSI / SI information table, the decoding is not performed to prevent an overheading of the system. An information processing method of a digital satellite broadcast receiver is disclosed. The disclosed invention comprises the steps of demultiplexing a transport stream received from a satellite in a demux portion of a digital satellite receiver; Decoding at the decoder PSI / SI information obtained by the demultiplexing; Setting the PSI / SI version by transferring PSI / SI table version information decoded by the decoder for decoding the PSI / SI information to the demux unit; Comparing with the version of PSI / SI table information of a transport stream which is subsequently demultiplexed in the demux unit; And when the version of the PSI / SI table information demultiplexed by the demux unit and the version of the PSI / SI table information previously set by the decoder are decoded, the decoding is performed on the demultiplexed PSI / SI table information. Do not make; characterized in that it comprises a.

Digital, satellite, PSI / SI, decoder, transport stream

Description

Information processing method of digital satellite broadcasting receiver {METHOD FOR INFORMATION PROCESSING OF DIGITAL SATELLITE BROADCASTING RECEIVER}

1 is a view for explaining a method for transmitting digital information according to a general satellite DMB method.

2 is a block diagram illustrating a receiver for receiving a signal in a satellite DMB scheme according to the prior art.

3 is a system block diagram of a demux unit area of a digital satellite broadcast receiver according to the present invention;

4A is a block diagram illustrating PSI / SI version management in a demux unit and a PSI / SI decoder according to the present invention.

4b is a flowchart for explaining a version management method of PSI / SI information of a digital satellite broadcast receiver according to the present invention;

* Description of the symbols for the main parts of the drawings *

201: DEMUX 202: PSI / SI buffer

203: PSI / SI decoder 204: CAS

205: audio decoder 206: video decoder

The present invention relates to a digital satellite broadcast receiver, and more particularly, in the case of a repeated PSI / SI information table when demultiplexing a transport stream in a digital satellite broadcast receiver to extract and decode the PSI / SI. The present invention relates to an information processing method of a digital satellite broadcast receiver which prevents overheading of a system by preventing decoding.

Digital satellite broadcasting has been spreading worldwide since 1994, when Direct TV of the United States conducted digital satellite broadcasting. Economically, cable television has been digitized in Europe and the United States, and terrestrial TV, which has attracted attention, has been digitized in all broadcast media in November 1998 by the United States and the United Kingdom, respectively. Our country also conducted digital satellite test broadcasting in July 1996, and is shouldering advanced countries in the digital broadcasting field.

The features of digital broadcasting are summarized as multichannel, high quality, and multifunctional. Among them, the multifunctionalization of digital broadcasting means that various services using data channels can be provided in addition to video and audio, and digital broadcasting is the biggest feature that can be differentiated from analog broadcasting.

The above-described digital broadcasting is a development of multiplexing technology, which can simultaneously transmit video, audio, data, etc. regardless of content and size. In addition, in digital broadcasting, a return channel is formed through a modem to enable an interactive service, and mounting of a processor and an operating system in a receiver enables various reception functions. Thanks to these technological developments, digital data broadcasting can provide viewers with a higher level of multimedia services beyond the limits of additional services such as analog data broadcasting.

Digital broadcast standards are largely divided into European DVB (Digital Video Broadcasting) method and American VSB (Vestigial Sideband Broadcasting) method. Among them, Korea adopts VSB as a standard for digital TV. In the case of DAB (Digital Audio Broadcasting), however, the DVB method is adopted as a standard, and DAB was initially limited to radio broadcasting using satellites, but gradually evolved into DMB (Digital Multimedia Broadcasting), which provides video services.

The DVB method improves the commonality of various media such as cable TV, satellite, terrestrial and public antenna (SMATV). The encoding and compression of signals is based on MPEG2.

In addition, the subscriber management function (Conditional Access) is prescribed to be based on a common scrambling algorithm.

The DVB system has substandards such as satellite digital TV broadcasting DVB-S (Satellite), digital cable TV broadcasting DVB-C (Cable), and terrestrial digital broadcasting DVB-T.

Among the systems for the DMB service, the digital system E specified in the ITU-RBO.1130-4 Recommendation converts the satellite signal transmitted by the DVB-S method into a CDM (Code Division Multiplex) signal that the terminal can receive and transmits it. Use

This repeater, which plays a role, is commonly referred to as a gap filler. The gap filler is a low-power retransmission station that receives and retransmits radio waves emitted from a transmission station so that broadcasts can be received in an area where radio waves are shielded, such as a high density building and a tunnel.

1 is a diagram illustrating a method of transmitting digital information according to a general satellite DMB scheme.

As shown in FIG. 1, the satellite DMB is serviced in the 2.535 to 2.655 GHz band corresponding to the microwave (UHF), which is a much higher band than the terrestrial wave. If terrestrial DMB covers radio waves from high mountains or buildings on the ground, satellite DMB is capable of broadcasting nationwide at once by launching radio waves from the satellite outside the atmosphere to the entire country.

Content providers, broadcasters, information providers, PSTN, PDN, mobile phones, etc. produced in the UP Link center, various contents such as news, music videos, sports, movies, dramas, songs, foreign languages, securities, transportation, weather, etc. Shoots into the satellite via the Ku band frequency (13.824-13.883 GHz).

The satellite transmits this signal to mobile terminals such as mobile phones, PDAs, etc. on the S-band allocated for DMB.

If it is difficult to directly receive the signal transmitted from the satellite, it is transmitted to the mobile terminal of the mobile phone, PDA, etc. on the ground through the repeater called Gap Filler described above. You can use DMB service anywhere.

In particular, while the multiplex of terrestrial DMB can accommodate about four channels, including one or two videos, satellite DMB can provide a much wider range of services.

2 is a block diagram illustrating a receiver for receiving a signal in a satellite DMB scheme according to the prior art.

As shown in FIG. 2, the receiver for receiving digital information received from a satellite and displaying the image as an image is an antenna (ANT) 1 for receiving a signal, and the signal received from the antenna 1 is transmitted from a transmitter. A front-end unit 10 for converting the previous signal, a descrambler 20 for de-cramble the encryption key according to the paid and free service for the restored signal from the front-end unit 10, A demux unit 21 which separates the signal released by the descrambler 20 into an audio signal, a video signal, and an information signal, and a decoder 23 which decodes the information signal separated by the demux unit 21; A voice decoder 26 for decoding the audio signal separated by the demux 21, an image decoder 25 for decoding the video signal separated by the demux 21, and Digital scene from Demux department (21) A is composed of a digital input-output unit 27 for input and output.

The front-end unit 10 includes a converter 10a for converting a signal received from the antenna 1 into a signal before transmission, and a CDM for restoring the signal converted from the converter 10a to a television signal according to the QPSK method. Demodulator 10b and decoder 10c for reconstructing the signal demodulated by the CDM demodulator 10b to a Transport Stream signal.

The receiving unit having the structure as described above operates as follows.

First, the signal received from the antenna 1 is converted into a transport stream signal by the converter 10a, the CDM demodulator 10b, and the decoder 10c of the front end unit 10 and then transmitted to the descrambler 20. do.

The signal transmitted to the descrambler 20 does not require descrambling when the satellite channel is a free channel, but in the case of the pay channel, the scramble MPEG signal is descrambled by a scramble card called a PCMCIA card. Since the broadcast can be viewed through the channel, such a scramble operation is performed according to the channel.

The signal scrambled by the descrambler 20 divides the transport stream signal into an OIO signal, a video signal, and an information signal by the demux unit 21, and then performs a decoding operation.

The decoder 23 decodes header information indicating characteristics of information received from the transport stream signal. Usually, program specific information / service information (PSI / SI) is separated and decoded, and then the information is decoded. The control signal is used to decode the video signal.

The PSI information includes a program association table (PAT) for specifying a PID (Packet Identification) of a transport stream packet for transmitting a program map table (PAT) related to a broadcast program, and a transport for transmitting each coded signal constituting a broadcast program. PMT (Program Map Table) information that specifies the PID of the stream packet, CAT (Condition Access Table) information indicating the relationship between the limited reception method and the EMM-S stream, information on the transmission path, and an information transmission system to associate the broadcast service with. NIT information indicating is included.

In addition, the SI information includes SDT information representing an information technology regarding a programming channel, current or next event information defined in a service, start time information, EIT (p / f) information consisting of content information, and a service defined in a transport stream. EIT (Event Information Table) information indicating broadcast information, broadcaster information presentation, BIT information having an information table for each transmission parameter of SI and PMT, TOT information indicating time and date information, and the like.

The demux 21 separates the transport stream signal from the audio signal and the video signal, and then decodes the audio stream and the video signal in the audio decoder 26, and in the case of the video signal, the image decoder ( Decode in 25) and output.

The digital input / output unit 27 inputs a digital signal to the demux unit 21 at high speed to control or outputs a digital signal directly from the demux unit 21.

When and how is the PSI / SI information of the transport stream signal separated from the demux unit 20 of the satellite DMB receiving unit as described above decoded by the decoder 23 and the audio and video signals are decoded and output? To control.

The PSI / SI information decoded by the decoder has its own PID according to each content, and is demuxed by the demux by such PID. That is, the PSI / SI table is repeatedly transmitted periodically.

The transport stream processed in the demux part has to be processed continuously without interruption and thus is in a performance-critical position in the system.

Since the PSI / SI information separated from the transport stream includes information for controlling the reproduced audio / video signal, the receiver performs decoding together with the audio / video signal.

However, when the satellite channels are the same and the programs to be reproduced are the same, the table version of the PSI / SI information is not changed. However, since the receiver must decode the same tables repeatedly, the performance is very inefficient.

That is, even if a PSI / SI table having the same contents as that already decoded by the PSI / SI decoder, the PSI / SI information table separated by the demux unit is decoded unconditionally in the system to control the reproduced audio / video signal.

Therefore, it is necessary to determine whether the decoding is performed according to the version of the PSI / SI information table, and to manage the system so as not to repeatedly decode the decoded PSI / SI table again.

According to the present invention, the demux unit of the satellite DMB receiver receives the PSI / SI information table version information decoded from the PSI / SI decoder and sets the version, and then demultiplexes the demultiplexed PSI / SI information table. The purpose of the present invention is to provide an information processing method of a digital satellite broadcast receiver which improves the system efficiency by not decoding the PSI / SI decoder in the case of the same version.

In order to achieve the above object, the information processing method of the digital satellite broadcast receiver according to the present invention,

Demultiplexing the transport stream received from the satellite in the demux portion of the digital satellite receiver;

Decoding at the decoder PSI / SI information obtained by the demultiplexing;

Setting the PSI / SI version by transferring PSI / SI table version information decoded by the decoder for decoding the PSI / SI information to the demux unit;

Comparing with the version of PSI / SI table information of a transport stream which is subsequently demultiplexed in the demux unit; And

If the version of the PSI / SI table information demultiplexed in the demux unit and the version of the PSI / SI table information previously set by the decoder are not decoded, the demultiplexed PSI / SI table information is not decoded. To prevent; characterized in that it comprises a.

Here, when the version of the PSI / SI table information demultiplexed by the demux and the version of the PSI / SI table information previously set by the decoder are different, the demultiplexed PSI / SI table is transmitted to the decoder. The method further includes the step of decoding and transferring new version information of the decoded PSI / SI to the demux unit to set a new version.

The demux unit demultiplexes the transport stream to separate an audio signal, a video signal, and a PSI / SI information signal, and the demux unit sets the PSI / SI table version information and a transport to demux The method may determine whether to decode the PSI / SI table information by comparing the PSI / SI table information of the stream.

According to the present invention, the demux unit of the satellite DMB method receiving unit receives the PSI / SI information table version information decoded from the PSI / SI decoder to set the version and then demultiplexes the PSI / SI information in the demux unit. Compared with the version of the table, when the same version is not decoded by the PSI / SI decoder, the system efficiency is improved.

As described above, in the digital satellite broadcasting system, a signal received from a satellite is converted into a signal in a transport stream form at the front end, and then separated into an audio, video, and information signal (PSI / SI) signal. .

Here, the configuration of the PSI / SI information signal directly related to the present invention will be described in detail.

In general, a digital broadcast signal provided in digital broadcast largely includes program information and PSI / SI (Program Specific Information / Service Information) information.

The program information refers to a TV program provided by a broadcaster for the purpose of broadcasting to a subscriber, and includes user information such as video information, audio information, and caption data.

Here, the program is provided as a transport stream. The transport stream (TS) refers to a protocol for transmitting video, audio, data, etc. simultaneously in one stream in a Motion Picture Coding Experts Group (MPEG) -2 system.

The transport stream (TS) is composed of one or more programs, and the transport stream (TS) header includes a program information constituting the entire stream, time information of the program, and control for controlling the entire system. Information enters.

The transport stream (TS) packet is composed of 188 bytes and has a 4-byte header at the top. The sync byte is one byte (0 * 47), and this value cannot be used in another part that is periodically repeated (for example, PID). Here, PID (13 bits) refers to an ID for classifying packets under payload.

The transport stream (TS) packet is composed of pure data such as video, audio, and data, and program specific information (PSI) information.

PSI information is data that is repeatedly transmitted within a predetermined time interval for initialization and the like in a receiver, and has a table structure divided into sections of 1024 bytes. PSI information begins with Table_id. In addition, the PSI information includes program association table (PAT) information, program map table (PMT) information, condition access table (CAT), and a user section (private section). The PAT information is a table of PIDs of PSI information, which informs PMT PID of each program.

PMT information informs the PID and the contents of the streams included in one program. CAT information provides information for receiving restriction. The user area is an area that can be determined and used by the user, and the PSIP information uses this area.

SI information refers to a set of tables designed to operate within all TSs for digital television (television). The purpose of the PSIP information is to describe the information of the virtual channel transmitted in a particular TS.

SI information includes a packet identification (ID) for demultiplexing video and audio information from a packet stream carried on a carrier channel and a modulation scheme of each channel required for normal reception of a broadcast program of each channel. Information, program guide information (including program title, start time, brief content, etc.), caption service availability, program grade, current time information, and the like are included.

Therefore, when a predetermined digital broadcast channel is selected, the digital broadcast receiver is tuned to the corresponding broadcast channel, and then separates the SI information from the packet stream, stores it in an internal memory, and demultiplexes the video and audio information using the stored SI information. do.

In addition, in more detail with respect to such SI information, the SI information may include the same PID (such as STT (System Time Table) information, RRT (Rating Region Table) information, MGT (Master Guide Table) and VCT (Virtual Channel Table) information. It consists of base table information having a packet identifier (ID), and information having a PID defined in the MGT such as event information (EIT) information and extended text table (ETT) information.

Here, the PID is an ID specifically assigned to distinguish between multiple elementary systems (ES) in a transport stream. The PID is located in the header of the TS.

STT information is one of the PSIP information of the Advanced Television System Committee (ATSC) standard, and provides information on the current date and time. The RRT information is one of the SI information of the ATSC standard, and provides rating information for a plurality of regions.

The MGT information provides PID information corresponding to a version number, a table length, and a table type for all SI information except STT information that operates independently from other tables.

The VCT information describes the virtual channel information. The VCT information describes the virtual channel, minor channel number, modulation mode, carrier frequency, program number, and SI information in the space where the detailed information of the virtual channel and event exists. Contains information about the ETM Location, Service Type, etc.

The EIT information includes information about broadcast contents. The EIT information includes event information (title, start time) for the virtual channel defined in the SI information. One EIT information has 3 hours of event information and can transmit a total of 128 EIT information from EIT-0 to EIT-127. ETT information refers to an option table used when describing virtual channels and events in PSIP information in detail.

The digital broadcast reception device receives the SI information and the PSI information as described above provided by the broadcaster.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a system block diagram of a demux unit region of a digital satellite broadcast receiver according to the present invention.

As shown in FIG. 3, the signal TS converted into the transport stream signal at the front end of the digital satellite broadcasting receiver is applied to the demux unit 201, and then an audio signal and a video are output. A signal and a PSI / SI information signal (program specification information) which is an information signal included in a transport stream are separated.

After separating the audio signal, the video signal, and the PSI / SI information signal, the respective separated signals are transmitted to respective decoders 205, 206, and 203 for decoding (decoding).

As described above, when the video signal and the audio signal are separated from the signal received by the receiver, the PSI / SI information signal includes all the specification information about the received program information such as the video signal, the time information of the audio signal, and the network information. And control the playback state.

In the present invention, the version of the PSI / SI information table to be decoded can be managed by adding a version setting function (Set Version) among the functions processed by the demux unit 201 of FIG. 3.

The function of the demux unit 201 filters the transport stream packet according to the PID of the transport stream, and demultiplexes it in order to select one program from various program signals received by the satellite broadcasting receiver. multiplexing).

That is, the demux unit 201 sets the transport stream PID, filters the transport stream packet according to the set transport stream PID, and then manages the filtered transport stream packet data.

In the present invention, it is possible to manage the version of the demultiplexed (demuxed) decoded information here so that the decoding of the previously filtered and demultiplexed information (table) is not repeated. The system efficiency is improved.

Therefore, the operation of the demux unit 201 is performed by initializing the demux unit 201 first, and then the audio signal, the video signal, and the PSI / SI information signal according to the transport stream PID. Demultiplexing to separate and extract

As such, when demultiplexing the first transport stream, demultiplexing and decoding are performed without version checking of the PSI / SI information signal.

Then, the version information of the PSI / SI table decoded by the PSI / SI decoder 203 is transmitted to the demux unit 201 to set the version.

Therefore, the PSI / SI information table demultiplexed in the demux unit is then compared with the set version, and in the case of PSI / SI version information set in the demux unit 201, the separated PSI / SI is separated. With respect to the SI information table, the PSI / SI decoder 203 does not decode again.

If the existing decoded PSI / SI table version is different from the version information set in the demux unit 201, the demux unit 201 demultiplexes the PSI / SI information to PSI / SI buffer. The data is transmitted to the PSI / SI decoder 203 through 202, and then decoded.

In this case, since decoding is performed on the new PSI / SI information, the PSI / SI decoder 203 sets a new PSI / SI table version by transferring the PSI / SI information table version thereof to the demux unit 201. Do it.

Thereafter, the demux unit 201 determines whether to decode by comparing the PSI / SI table version to be demultiplexed with the newly set PSI / SI table version in the same manner as described above.

The video signal demuxed and separated by the demux 201 is transferred to the video decoder 206 to perform a decoding operation, and the separated audio signal is transferred to the audio decoder 205 to perform a decoding operation.

In this case, the CAS (Conditional Access System) controls that the decoding is performed so that the transport stream selected by the demux unit 201 matches the corresponding program information.

4A is a block diagram illustrating PSI / SI version management in a demux unit and a PSI / SI decoder according to the present invention.

As shown in FIG. 4A, the demux unit 201 and the PSI / SI decoder 203 decode the PSI / SI table while comparing the PSI / SI version information with the PSI / SI buffer 202 interposed therebetween. Determine.

The demux unit 201 transmits the separated PSI / SI information to the PSI / SI buffer 202 while demultiplexing (demuxing) a transport stream and then transmits the PSI / SI according to the PSI / SI table. The decoder 203 performs decoding.

The PSI / SI decoder 203 transmits version information of the decoded PSI / SI table to the demux unit 201 to set a version of the decoded PSI / SI table in the demux unit 201.

Thereafter, the demux unit 201 separates the video signal, the audio signal, and the PSI / SI information signal, and then the PSI / SI version and the PSI / SI version previously decoded by the PSI / SI decoder 203. In this case, the separated PSI / SI information is not transmitted to the PSI / SI buffer 202 so that the PSI / SI decoder 203 does not repeatedly decode.

As such, after setting the version of the demux unit 201 according to the PSI / SI table version decoded by the PSI / SI decoder 203, in the case of the same PSI / SI table, the decoding is not performed. In the case of a version of the PSI / SI table, the overhead can be reduced by performing decoding.

4B is a flowchart for explaining a version management method of PSI / SI information of a digital satellite broadcast receiver according to the present invention.

As shown in FIG. 4B, the demux of the digital satellite receiver demultiplexes the transport stream received from the satellite into audio signals, video signals, and PSI / SI information signals (S401).

Then, the PSI / SI information obtained by demultiplexing is decoded by the decoder to control the audio signal and the video signal (S402).

In this case, the PSI / SI decoder transmits version information of the PSI / SI table to be decoded to set the version of the demux unit (S403).

If the version is set to the demux unit, when the transport stream TS is demultiplexed in the demux unit, the PSI / SI version information is compared with the set PSI / SI table version information (S404).

When the PSI / SI table version information demultiplexed by the demux unit and the preset PSI / SI table version information are different, the demultiplexed PSI / SI information is transmitted to the PSI / SI decoder to perform decoding. (S405)

Then, the new PSI / SI version information decoded by the PSI / SI decoder is transferred to the demux unit to set a new version.

Therefore, when the transport stream is continuously received and demultiplexed after the demux unit, comparison is performed with the PSI / SI version information set in the demux unit (S406).

If there is no transport stream received in the demux unit, the comparison operation is not performed in that state, and the demux unit is set according to the last version.                     

However, when the PSI / SI version information demultiplexed by the demux unit and the preset PSI / SI version information are the same, the PSI / SI decoder does not repeatedly decode the demultiplexed PSI / SI information. (S407)

That is, when the same as previously decoded PSI / SI information, it is sufficient to display the video signal and the audio signal according to the decoded previous information.

By doing so, it is possible to improve the signal processing efficiency in the digital satellite broadcasting receiver to prevent the system's overheading phenomenon.

As described above, the present invention adds a version management function to the demux unit so that the demux unit sets the PSI / SI table version information and the transport stream to demux each time the demux is transported. The PSI / SI table information is used to determine whether to decode the PSI / SI.

As described in detail above, the present invention receives the decoded version from the PSI / SI decoder in the demux unit of the satellite DMB receiver and determines whether the PSI / SI table has been previously decoded when the transport stream is decoded. In the case of PSI / SI information that has been decoded, the system efficiency is improved so that decoding is not performed again.

The present invention is not limited to the above-described embodiments, and various changes can be made by those skilled in the art without departing from the gist of the present invention as claimed in the following claims.

Claims (4)

Demultiplexing the transport stream received from the satellite in the demux portion of the digital satellite receiver; Decoding at the decoder PSI / SI information obtained by the demultiplexing; Setting the PSI / SI version by transferring PSI / SI table version information decoded by the decoder for decoding the PSI / SI information to the demux unit; Comparing with the version of PSI / SI table information of a transport stream which is subsequently demultiplexed in the demux unit; And If the version of the PSI / SI table information demultiplexed in the demux unit and the version of the PSI / SI table information previously set by the decoder are not decoded, the demultiplexed PSI / SI table information is not decoded. Information processing method of the digital satellite broadcast receiver comprising a; The method of claim 1, If the version of the PSI / SI table information demultiplexed by the demux unit and the version of the PSI / SI table information previously set by the decoder are different, the demultiplexed PSI / SI table is transmitted to the decoder for decoding. And proceeding with transmitting the new version information of the decoded PSI / SI to the demux unit to set a new version of the information processing method of the digital satellite broadcast receiver. The method of claim 1, The demux unit demultiplexes a transport stream to separate an audio signal, a video signal, and a PSI / SI information signal. The method of claim 1, The demux unit determines whether to decode the PSI / SI table information by comparing the set PSI / SI table version information with the PSI / SI table information of the transport stream to be demuxed. Information processing method.

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