DMB 서비스 기술

DMB 서비스 기술

임 영 권[email protected]

Characteristics of T-DMB

Backward Compatibility Efficient use of bandwidth Convergence between broadcasting &

communication

Backward Compatibility

DMB 서비스 구조

" 비디오 서비스 1 "앙상블 번

“ 1 ”알파 라디오 “ ”베타 라디오 “ 2 ”알파 라디오

오디오 알파TMC

알파SI

비디오-1 부오디오 비디오-2

서브채널a

서브채널b

서브채널c

서브채널d

서브채널63FIDC

MCI SI

앙상블

서비스

서비스컴포넌트

주 서비스 채널 고속 정보 채널

DMB 송신 개념도

FIC 데이터서비스

다중제어데이터

서비스정보

오디오서비스

데이터서비스

비디오송신 신호

비디오서비스

스트림모드

고속 정보(FIC) 경로

서비스 정보(SI) 경로

디지털라디오 오디오 프레임 경로

주서비스

다중화기

전송프레임

다중화기

OFDM신호

발생기

데이터 경로

선택적수신제한

스크램블러

에너지분산

스크램블러

길쌈부호화기

시간인터리버

CIFs

초단파 디지털라디오방송 송신 시스템 (TTAS.KO- 07.0024 )

비디오다중화기

Interactive AudiovisualScene

Elementary Streams

Composition and Rendering

Display andUser

Interaction

Eureka 147 DAB channel

DeliveryLayer

DeliveryLayer

SL SL SLSync LayerSync Layer

SceneDescriptionInformation

ObjectDescriptor

CompressionLayer

CompressionLayer

SL

UpstreamInformation

SL

AV ObjectsData

SL-Packetized Streams

(PES)MPEG-2

TS

High level architecture

DMB components

EU-147 Stream ModeEU-147 Stream Mode

MPEG-2 TS MultiplexingMPEG-2 TS Multiplexing

MPEG-4 SLEncapsulation






MPEG-4 AVCVideo

MPEG-4 AVCVideo

MPEG-4BSACAudio

MPEG-4BSACAudio

MPEG-4 BIFSInteractiveContents

MPEG-4 BIFSInteractiveContents

Forward Error CorrectionForward Error Correction

Packet Structure

김용한 , “ 지상파 DMB 표준” , 한국방송공학회 디지털방송기술워크샵 , 2004.10.12

Efficient Use of Bandwidth

FEC

Target BER = 10-8

Two well-known methods convolutional interleaving reed-solomon coding

Sourcedata Synch.

channelgenerator

OFDMsignal generator

FIC and MSC(frequencyinterleaved)

symbolgenerator

Convolutionalencoder

TimeInterleaver

Energydispersalscrambler

ConvolutionalInterleaver

RSencoder A

A

MPEG-2 TS

Stream Multiplexing Program association table Program map table PID, stream_id

Random Access Fixed size TS packets with sync. byte Start codes

Framing variable size PES (Packetized elementary stream) packet fixed sized TS packet

TS packet headers

syncbyte

transporterror

indicator

payloadunit startindicator

transportpriority

PIDtransport

scramblingcontrol

adaptationfield

control

continuitycounter

adaptationfield

8 1 1 1 13 2 2 4

adaptationfield

length

discontinuityindicator

randomaccess

indicator

elementarystream priority

indicator

5 flagsoptionalfields

8 1 1 1 5

stuffingbytes

PCR OPCRsplice

countdown

transportprivatedata

length

adaptationfield

extensionlength

optionalfields

42 42 8 8 8

transportprivatedata

3 flags

3

header payload

188 bytes

header payload header payloadTransportpacketstream

00

PES packet headers

packet startcode prefix

stream idPES

packetlength

optionalPES

HEADERPES packet data bytes

24 8 16

‘10’PES

scramblingcontrol

PESpriority

dataalignmentindicator

copyrightoriginalor copy

7 flags

PESheaderdata

length

optionalfields

stuffingbytes(0xFF)

2 2 1 1 1 1 8 8 m*8

PTSDTS

ESCRESrate

DSMtrick

mode

additionalcopy info

previousPESCRC

33 42 22 8

0xFA

16

PES extension

8

0b00 0b1

0b100b00

MPEG-4 Systems

SL for Synchronization CTS (Composition Time Stamps) DTS (Decoding Time Stamps)

BIFS for Interactive composite multimedia OD Framework Scene Description Only one audio Only one video

MPEG-4 descriptors

shall use ObjectDescriptor InitialObjectDescriptor ESDescriptor DecoderConfigDescriptor SLConfigDescriptor

shall not use IPMPDesrciptor IPMPDescriptorPointer IPIDescriptorPointer

ObjectTypeIndication

0x02 Systems ISO/IEC 14496-10x21 Visual ISO/IEC 14496-10

0x40 Audio ISO/IEC 14496-3

0x6C Visual ISO/IEC 10918-1 (JPEG)

0xC0 – 0xFE

user private

streamType

0x01 ObjectDescriptorStream

0x02 ClockReferenceStream

0x03 SceneDescriptionStream

0x04 VisualStream

0x05 AudioStream

0x20 - 0x3F user private

SL packet encapsulation

useAccessUnitStartFlag useAccessUnitEndFlag useRandomAccessPointFlag = 0 hasRandomAccessUnitsOnlyFlag= 0 usePaddingFlag = 0 useIdleFlag = 1 useTimeStampsFlag = 1 durationFlag

timeScale accessUnitDuration compositionUnitDuration

SL packet encapsulation

timeStampResolution : 90kHz OCRResolution : 90kHz timeStampLength : ≤ 33 bits OCRLength : ≤ 33bits AU_Length = 0 instantBitrateLength degradationPriorityLength = 0 AU_seqNumLength = 0 packetSeqNumLength = 0

4on2

Timing relationship MPEG-4 OTB is locked to the MPEG-2 STC PTS shall be present if and only if OCR is carried.

SL-packetized streams in PES packets Stream_id = 0xFA A single SL-packetized stream may be mapped into a single

PES One and only one SL packet shall consist the payload of PES

packet

Random Access

PAT single program per TS period ≤ 500 msec.

PMT IOD_descriptor in the first loop SL_descriptor in the second loop period ≤ 500 msec.

PCR period ≤ 100 msec OCR period ≤ 700 msec CTS period ≤ 700 msec

4on2 Content Access Procedure

MPEG-2 Transport Stream

TS Packet : PID =0x0000

Program Association Section

...

{ ...

program_number =0x0001 program_map_PID =0x0100 ...

}CRC_32


..program_stream_info_length

1st_descriptor_loop { IOD_descriptor { }

}{ stream_type =0x13 elementary_PID =0x0111

2nd_descriptor_loop { SL_descriptor { ES_ID =0x0011

}

} stream_type =0x13 elementary_PID =0x0112


}

}

TS Program Map Section

stream_type =0x12 elementary_PID =0x0113


}

} stream_type =0x12 elementary_PID =0x0114

2nd_descriptor_loop { SL_descriptor { ES_ID =0x0014 }

}...

.

.

.

.

.

.


ISO_IEC_14496_Section

BIFS-Command Stream

...ES_Descriptor { ES_ID =0x0011 streamType =“SD stream” specificInfo =“BIFS-com”}ES_Descriptor { ES_ID =0x0012 streamType =“OD stream”}...

Initial Object Descriptor


ISO_IEC_14496_Section

OD Stream

ObjectDescriptor { ES_Descriptor { ES_ID =0x0013 streamType =“SD stream” specificInfo =“BIFS-Anim” }}ObjectDescriptor { ES_Descriptor { ES_ID =0x0014 streamType =“IPMP stream” }}

Object Descriptor Stream


BIFS-Anim Stream

PES Packet : stream_id =‘1111 1010’

1. acquire PMT

2. identify IOD

3. identify ESD

4. identify SLCD5. generate PID v.s. ESID map table

7. Locate OD Stream

8. Locate media streams

6. Locate SceneDescriptionStream

Video Profile

Baseline profile No Arbitrary slice order PPS(Picture Parameter Sets)

num_slice_groups_minus1 = 0 redundant_pic_cnt_present_flag = 0

SPS(Sequence Parameter Sets) pic_order_cnt_type = 2 num_ref_frames = 3

Level 1.3 Picture Format

Vertical MV component range (MaxVmvR) : [-64,+63.75] Maximum Frame Rate : 30fps MaxDPB : 445.5kbytes IDR picture period ≤ 500 msec.

FormatPicWidthInM

bsPicHeightInM

bsPicSizeInMbs

QCIF 11 9 90

QVGA 20 15 300

WDF 24 14 336

CIF 22 18 396

Video Level

Audio

ISO/IEC 14496-3 ER BASC Audio Object (0x22) Restrictions

AudioSpecificConfig() epConfig : 0 frameLengthFlag : 0 dependsOnCoreCoder : 0

bsac_header() SBA_mode : 0

general_header() ltp_data_present : 0

Audio

항목 내용

Sampling freq.(Hz) 24000, 44100, 48000

Number of channel 1, 2

Number of objects 1

Maximum bit rate 128 kbps (stereo)

Convergence

Concept

DMB

MPEG-4BIFS

무선인터넷

VoDAoD쇼핑

벨소리연결음

….

MPEG-4 Systems Core2D profile

Video on Demand interactive audio-video over the Internet scalable content delivery

Enhanced digital TV MPEG-4 video over MPEG-2 Picture in Picture Interactive Electronic Program Guides enriched TV programs

Advertisement animated banners video warping and incrustation Personalization web links

Interactive presentations basic graphics animations e-commerce interactive contests or voting

Core2D Scene Description Profile

basic 2D composition 2D texturing local interaction local animation BIFS updates quantization access to web links and sub-scenes back channel (ServerCommand) VoD features (MediaControl, MediaSensor)

Conclusion

EU-147 Stream Mode FEC : RS + Convolutional Interleaving Transport : MPEG-2 TS Adaptation : MPEG-4 SL Video : MPEG-4 AVC Baseline Profile Audio : MPEG-4 BSAC Graphics & Data : MPEG-4 System Core2D Profile

Acknowledgementto

All of M2B members

Documents

DMB 서비스 기술