KR100609151B1 - Digital satellite broadcasting receiver and method for information processing of using the same - Google Patents

Abstract

The present invention discloses a digital satellite broadcast receiver and an information processing method thereof so that audio and video can be constantly reproduced in a satellite broadcast receiver without interruption. The disclosed invention comprises the steps of receiving a program information signal and converting it into a transport stream; Demultiplexing the transport stream in a demux unit to separate and extract an audio signal, a video signal, and PSI / SI information; Obtaining reproduction bit rate information and buffering time information of an audio / video signal corresponding to each program unit from the extracted PSI / SI information; Obtaining a control buffer size for controlling the buffering size of the reproduced audio / video signal by using the reproduction bit rate information and the buffering time information of the audio / video signal obtained from the PSI / SI information; When buffering to reproduce the audio / video signal, comparing each other with a control buffer size obtained for controlling the buffering of the audio / video signal; And reproducing the audio / video signal by transmitting the buffered audio / video signal to a codec when the control buffer size is smaller than the buffering size of the audio / video signal being buffered for the reproduction. It is characterized by.

Description

Digital satellite broadcasting receiver and information processing method {DIGITAL SATELLITE BROADCASTING RECEIVER AND METHOD FOR INFORMATION PROCESSING OF USING THE SAME}

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 present invention.

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

4 is a flowchart for explaining a method of controlling an audio / video signal according to the present invention;

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

1: antenna 10: front end

20: Descrambler 21: Demux Part

23 decoder 25 image decoding unit

26: voice decoder 27: digital I / O

The present invention relates to a digital satellite broadcast receiver, and more particularly, to a digital satellite broadcast receiver and an information processing method for allowing audio and video to be constantly played back in a satellite broadcast receiver without interruption. will be.

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.

When the digital signal is received from the satellite, the DMB standard, which is the digital satellite broadcasting standard described above, demultiplexes the PSI / SI information signal including the audio signal / video signal and program specification information in a program unit. .

In particular, the PSI / SI information is set in a table with various information about the program information, output time, program type, show time of the program, matching time of audio and video information, and the like.

As such, the information is transmitted by the broadcasting station when a program is created and then transmitted to the satellite.

Then, the receiver receives this, separates each audio signal, video signal, and PSI / SI information on a program-by-program basis, and then decodes and reproduces them.

 However, in order to decode the audio signal and the video signal and then play them, buffering is performed in units of a certain size, and then the playback is performed. There is a problem that occurs frequently.

That is, if the size of the audio and video signals that are decoded and then buffered before playback differs from program to program, and they do not properly match the buffer size that decodes and buffers PSI / SI information such as time information, the audio / played audio / The video is not continuous.

For example, if the PSI / SI program specification information is all buffered before playback, but the audio and video signals are not buffered for playback, playback stops until the video and audio signals are buffered. Occurs.

The present invention obtains the control buffer size for controlling the reproduction buffer size of the audio / video signal from the reproduction bit rate information and the reproduction buffering time information of the audio / video signal reproduced from the PSI / SI information, and then based on this value, And an information processing method of a digital satellite broadcast receiver capable of continuously playing a program by controlling a buffer amount of a video signal.

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

Receiving a program information signal and converting it to a transport stream;

Demultiplexing the transport stream in a demux unit to separate and extract an audio signal, a video signal, and PSI / SI information;

Obtaining reproduction bit rate information and buffering time information of an audio / video signal corresponding to each program unit from the extracted PSI / SI information;

Obtaining a control buffer size for controlling the buffering size of the reproduced audio / video signal by using the reproduction bit rate information and the buffering time information of the audio / video signal obtained from the PSI / SI information;

When buffering to reproduce the audio / video signal, comparing each other with a control buffer size obtained for controlling the buffering of the audio / video signal; And

Reproducing an audio / video signal by transmitting the buffered audio / video signal to a codec if the control buffer size is smaller than the buffering size of the audio / video signal being buffered for the playback. It features.

Here, when the control buffer size is larger than the buffering size of the audio / video signal being buffered for the playback, the audio / video signal until the buffered audio / video signal is larger than the control buffer size. Continuing to buffer; And

And if the buffer size of the buffered audio / video signal is larger than the control buffer size, transmitting the buffered audio / video signal to a codec to reproduce an audio / video signal.

And encoding and transmitting the program information signal, adding reproduction bit rate information to the audio and video information corresponding to the type of program and buffering time information when they are reproduced, and buffering to reproduce the audio / video signal. The size of the audio / video signal can be continuously reproduced by reproducing the audio / video signal in a state where the size is always larger than the size of the control buffer.

Digital satellite broadcast receiver according to the present invention,

An antenna for receiving a program information signal;

A front end unit converting the program information signal received by the antenna into a transport stream signal;

A demux unit for dividing a signal converted into a transport stream signal by the front end unit into an audio signal, a video signal, and a PSI / SI information signal according to each program;

Decoders for decoding the demultiplexed audio signal, video signal and PSI / SI information signal in the demux unit;

A buffer unit for buffering an audio signal and a video signal decoded from the decoders;

A control buffer for controlling the buffering size of the buffered audio signal and the video signal by obtaining bit rate information for reproduction and buffer time information for reproduction from the PSI / SI information of the audio signal and the video signal buffered in the buffer unit. An audio / video system controller for obtaining magnitude values; And

And a buffer controller for controlling the size buffered in the buffer unit according to the control buffer size value obtained by the audio / video system controller.

The method may further include a codec for reproducing the audio signal and the video signal buffered in the buffer unit under the control of the buffer controller.

The audio / video system controller obtains a control buffer size for controlling the audio and video signals buffered in the buffer unit, and then controls the buffer controller to control the buffering buffer size in the buffer unit based on the value. The buffer controller is configured to convert the buffered audio signal and the video signal when the buffered size of the audio signal and the video signal has a value larger than the control buffer size obtained by the audio / video system controller. It is characterized in that to play in.

According to the present invention, the control buffer size for controlling the reproduction buffer size of the audio / video signal is obtained from the reproduction bit rate information and the reproduction buffering time information of the audio / video signal reproduced from the PSI / SI information. By controlling the buffer amount of the signal and the video signal, there is an advantage that the program can be played continuously without interruption.

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

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

As shown in FIG. 2, a receiver for displaying digital information received from a satellite as an image includes an antenna (ANT) 1 for receiving a signal, and a signal received from the antenna 1 as a signal before being transmitted from a transmitter. A descrambler 20 which de-crambles the encryption key according to a paid and free service for the restored signal from the front end unit 10, the front-end unit 10, and the descrambler A demux unit 21 for dividing the signal canceled at 20 into an audio signal, a video signal, and an information signal, a decoder 23 for decoding the information signal separated at the demux unit 21, and A voice decoder 26 for decoding the audio signal separated by the mux unit 21, an image decoder 25 for decoding the video signal separated by the demux unit 21, and the demux unit at high speed. Input / output digital signal from 21 It consists of a digital input-output unit 27.

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 program 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 to the descrambler 20. Is sent.

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 audio signal, a video signal, and a PSI / SI information signal (program specification information) 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 packet identification (PAT) 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 indicating an information technology about a programming channel, current or next event information defined in a service, start time information, content information, and EIT (p / f) information defined in a transport stream. It consists of EIT (Event Information Table) information indicating broadcast information of a service, 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.

In particular, in the present invention, when encoding and transmitting an audio / video signal, reproduction bit rate information and reproduction buffering time information for reproducing respective program information are added to the PSI / SI information.

When the PSI / SI information is separated and extracted from the program information received at the receiver and then decoded, the control buffer size is obtained using the reproduction bit rate information and the reproduction buffering time information for each program information, and the audio / video Controls playback so that playback is seamless.

That is, a buffering size value for proper reproduction is obtained from the reproduction bit rate information and the buffering time information of the video signal and the audio signal for each program, and buffering is performed up to at least the obtained buffering value, so that the program can be reproduced continuously. .

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, a receiver for encoding program information produced by a broadcasting station and then transmitting the program information to a satellite and receiving program information from the satellite is illustrated in detail.

The demux unit converts the program information received from the receiving unit into a transport stream in the front-end unit shown in FIG. 2 and then demultiplexes and demultiplexes the extracted program according to each program type ( DEMUX: 21).

When the demux 21 demultiplexes the audio signal, the video signal, and the PSI / SI information, the demux unit 21 transmits the audio signal to the corresponding audio / video decoder 31 and the PSI / SI decoder 35. Decoded.

A buffer unit 32 that buffers the audio and video signals decoded from the decoders 31 and 35 before reproduction, and an audio signal and a video demultiplexed by the demux unit 21. Control obtained from the audio / video system controller 36 which obtains a control buffer size value from the reproduction bit rate information and the buffering time information from the PSI / SI information having the program specification information of the signal; A buffer controller 38 for controlling a buffering size of an audio / video signal (Audio / Video: A / V) buffered in the buffer unit 32 using a buffer size, and a control of the buffer controller 38 Is composed of a codec 33 for reproducing the audio / video signal buffered from the buffer unit 32.

In such a system, when decoding the PSI / SI information separated by the demux unit 21, the reproduction bit rate information and the reproduction buffering time information added to each of the program information are transmitted to the buffer controller 38 and audio. The amount of buffer in the buffer unit 32 is adjusted in comparison with the video / video controller 36.

In this way, the size of the control buffer in the audio / video system controller 36 and the buffer controller 32 and the buffering size of the audio / video signal buffered in the buffer unit 32 are compared. By adjusting the buffer amount of, the playback can be performed continuously without interruption.

That is, a control buffer size value suitable for playback is obtained from the bit rate and buffer time when the decoded audio and video signals are reproduced, and the buffer size buffered in the buffer unit 32 is always the control buffer based on this value. If the playback is larger than the size, continuous playback can be performed.

In general, since the reproduction buffering size of the audio signal and the video signal is different according to the program type, the reproduction bit rate information and the reproduction buffering time information added to the PSI / SI information of the respective programs are different.

Therefore, when the audio signal, the video signal, and the PSI / SI information are extracted, decoded, and reproduced, the control buffer size is obtained by multiplying the reproduction bit rate and the buffering time of the reproduced audio signal and the video signal.

Then, the buffer controller 38 controls the buffering size of the audio signal and the video signal buffered by the buffer unit 32 based on the control buffer size.

Accordingly, the present invention obtains the control buffer size from the PSI / SI information according to each program type, and then adjusts the buffering size of the audio signal and the video signal buffered by the buffer unit 32 using this value. Enable playback of audio and video signals.

4 is a flowchart for explaining a method of controlling an audio / video signal according to the present invention.

As shown in FIG. 4, the program information signal received from the satellite is converted into a transport stream (TS), and then the transport stream is transmitted to a demux unit (DEMUX).

The demux unit performs a demultiplexing operation to separate and extract the audio signal, the video signal, and the PSI / SI information included in the transport stream (S301).

The reproduction bit rate information and the reproduction buffering time information of the audio signal and the video signal reproduced from the PSI / SI information table extracted by the demux unit are obtained (S302).

The audio / video system controller obtains a control buffer size capable of adjusting the buffering size of the audio signal and the video signal reproduced in the buffer unit by multiplying the reproduction bit rate information and the reproduction buffering time information thus obtained (S303).

At this time, the audio signal and the video signal separated and extracted by the demux unit are decoded by the decoder and then buffered by the buffer unit before reproduction (S304).

When the audio signal and the video signal to be reproduced in the buffer unit are buffered as described above, the buffering size of the audio signal and the video signal buffered in the buffer unit in the audio / video system controller and the buffer controller are compared based on the control buffer size. Control whether playback is performed. (S305)

When the control buffer size is smaller than the buffering size of the audio / video signal buffered in the buffer unit for the reproduction, the buffered audio / video signal is transmitted to a codec to reproduce the audio / video signal. (S305, S306)

If the control buffer size is larger than the buffering size of the audio / video signal being buffered for the playback, continuous playback is not possible until the buffered audio / video signal is larger than the control buffer size. Continue buffering the audio / video signal (S305, S304).

Then, when the buffer size of the buffered audio / video signal becomes larger than the control buffer size, the buffered controller controls the buffered audio / video signal so that the audio / video signal can be reproduced by the codec. , S304)

Therefore, in the present invention, by reproducing the audio / video signal while the buffer size buffered for reproducing the audio / video signal is always larger than the control buffer size, the audio / video signal is continuously and continuously. To play.

In addition, among the various broadcast channels played by one receiver, a program played in one broadcast channel plays audio / video quickly, and a program played in a certain channel always plays without interruption even if the audio / video plays slowly. There is an advantage to regeneration.

As described in detail above, the present invention obtains a control buffer size for controlling the reproduction buffer size of the audio / video signal from the reproduction bit rate information and the reproduction buffering time information of the audio / video signal reproduced from the PSI / SI information. By controlling the buffer amount of the audio and video signals based on this value, the program can be played continuously without interruption.

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 (8)

Receiving a program information signal and converting it to a transport stream; Demultiplexing the transport stream in a demux unit to separate and extract an audio signal, a video signal, and PSI / SI information; Obtaining reproduction bit rate information and buffering time information of an audio / video signal corresponding to each program unit from the extracted PSI / SI (Program Specific Information / Service Information) information; Obtaining a control buffer size for controlling the buffering size of the reproduced audio / video signal by using the reproduction bit rate information and the buffering time information of the audio / video signal obtained from the PSI / SI information; When buffering to reproduce the audio / video signal, comparing each other with a control buffer size obtained for controlling the buffering of the audio / video signal; And Reproducing an audio / video signal by transmitting the buffered audio / video signal to a codec if the control buffer size is smaller than the buffering size of the audio / video signal being buffered for the playback. An information processing method of a digital satellite broadcast receiver characterized by the above-mentioned. The method of claim 1, If the control buffer size is greater than the buffering size of the audio / video signal being buffered for the playback, buffering the audio / video signal until the buffered audio / video signal is larger than the control buffer size. Continuing; And And when the buffer size of the buffered audio / video signal is larger than the control buffer size, transmitting the buffered audio / video signal to a codec to reproduce an audio / video signal. Information processing method of broadcast receiver. The method of claim 1, And reproducing bit rate information and buffering time information when they are reproduced to audio and video information corresponding to a type of a program when encoding and transmitting the program information signal. The method of claim 1, The buffer size buffered to reproduce the audio / video signal is reproduced by playing the audio / video signal with a value always larger than the control buffer size, so that the audio / video signal can be continuously reproduced. Information processing method of satellite broadcasting receiver. An antenna for receiving a program information signal; A front end unit converting the program information signal received by the antenna into a transport stream signal; A demux unit for dividing a signal converted into a transport stream signal by the front end unit into an audio signal, a video signal, and a PSI / SI information signal according to each program; Decoders for decoding the demultiplexed audio signal, video signal and PSI / SI information signal in the demux unit; A buffer unit for buffering an audio signal and a video signal decoded from the decoders; A control buffer for controlling the buffering size of the buffered audio signal and the video signal by obtaining bit rate information for reproduction and buffer time information for reproduction from the PSI / SI information of the audio signal and the video signal buffered in the buffer unit. An audio / video system controller for obtaining magnitude values; And And a buffer controller for controlling a size buffered in the buffer unit according to a control buffer size value obtained by the audio / video system controller. The method of claim 5, And a codec for reproducing an audio signal and a video signal buffered in the buffer unit under control of the buffer controller. The method of claim 5, The audio / video system controller obtains a control buffer size for controlling the audio signal and the video signal buffered in the buffer unit, and then causes the buffer controller to control the buffering buffer size in the buffer unit based on the value. Digital satellite broadcast receiver, characterized in that. The method of claim 6, The buffer controller reproduces the buffered audio signal and the video signal when the audio signal and the video signal have a value larger than the control buffer size obtained by the audio / video system controller. Digital satellite broadcast receiver characterized in that to make.

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