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MPEG-2 High Rate Video over 1394 and Implications for 802
MPEG-2 High Rate Video over 1394 and Implications for 802
Outline
Outline
Introduction
Introduction
MPEG2 Data
MPEG2 Data
TS Packet Transmission Rate
TS Packet Transmission Rate
Issues for 1394 AV over 802
Issues for 1394 AV over 802
Issues for 1394 AV over 802
Issues for 1394 AV over 802
Appendix: Formats for 1394/IEC61883-4
Appendix: Formats for 1394/IEC61883-4
1394 MPEG2-TS Transfer
1394 MPEG2-TS Transfer
1394 MPEG2-TS Transfer (cont
1394 MPEG2-TS Transfer (cont
TS Packet Transmission Rate
TS Packet Transmission Rate
Header
Header
1394 Header
1394 Header
CIP Header
CIP Header
CIP Header (MPEG2-TS)
CIP Header (MPEG2-TS)
Source Packet Header
Source Packet Header
DV Format (SD-DVCR)
DV Format (SD-DVCR)
1394 DV Transfer (for reference)
1394 DV Transfer (for reference)
DV Format Rate (SD-DVCR)
DV Format Rate (SD-DVCR)
CIP Header (SD-DVCR)
CIP Header (SD-DVCR)
CIP Header (SD-DVCR)
CIP Header (SD-DVCR)
DV Format Rate of 1394 transfer
DV Format Rate of 1394 transfer

Презентация: «MPEG-2 High Rate Video over 1394 and Implications for 802». Автор: Terada. Файл: «MPEG-2 High Rate Video over 1394 and Implications for 802.ppt». Размер zip-архива: 88 КБ.

MPEG-2 High Rate Video over 1394 and Implications for 802

содержание презентации «MPEG-2 High Rate Video over 1394 and Implications for 802.ppt»
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1 MPEG-2 High Rate Video over 1394 and Implications for 802

MPEG-2 High Rate Video over 1394 and Implications for 802

11e

John Kowalski Sharp Corporation

September, 2000

Slide 1

John M. Kowalski,

2 Outline

Outline

Introduction MPEG-2 High Rate Video and Transport Stream Description (1394/ IEC 61883-4) Throughput Latency, Jitter Requirements Issues for 1394 AV over 802.11 Appendix: Formats for 1394/IEC61883-4

September, 2000

Slide 2

John M. Kowalski,

3 Introduction

Introduction

Evaluation Criteria Group identified high rate MPEG as a data stream type for use in 802.11e. High Rate MPEG is closely tied to 1394, and IEC 61883-4. 1394, although not strictly part of requirements, is “nice to have” capability for 11e proposals. Hence this summary of high rate MPEG via 1394/IEC 61883-4.

September, 2000

Slide 3

John M. Kowalski,

4 MPEG2 Data

MPEG2 Data

MPEG2 ensures the data rate of one transponder. For CS, the actual data rate of one transponder is, for HDTV-like video 29.2Mbps. For BS Digital, the actual data rate of one transponder is 26.085Mbps. Multiple streams are included in one transponder. 3Mbps – 6 Mbps is used for bit rate of one channel. For HDTV, one channel uses one transponder. Over 22Mbps is required as the data rate. About 24Mbps is upper limit because of their overhead. Key requirement: 1394/IEC61883-4 uses isochronous, fixed length packets.

September, 2000

Slide 4

John M. Kowalski,

5 TS Packet Transmission Rate

TS Packet Transmission Rate

Maximum jitter is assumed to be about 311 ms on transmit, and 50ms from real time interface, from IEC 61883-4. Latency arbitrated in 1394.

September, 2000

Slide 5

John M. Kowalski,

6 Issues for 1394 AV over 802

Issues for 1394 AV over 802

11

1394/6883-4 wants to see isochronous streams. So a lean (low overhead, not complex) PCF is a must. Small packet sizes of constant length (480 bytes +24 bytes O/H). With Breezecom’s (nonoptimized?) estimates for efficiency (document 99-256) an efficiency of at best 47% can be expected in the PCF, for 400 bytes. Buffering must be applied to compensate for 802.11 behavior which breaks the standard (as a recommended practice?)

September, 2000

Slide 6

John M. Kowalski,

7 Issues for 1394 AV over 802

Issues for 1394 AV over 802

11 (cont.)

How to transfer the QoS information? Must map 1394 information into 802.1p/q priority tags. How to allocate the bandwidth, jitter? Efficiency- how best to format over 802.11 Power save requirements for portable AV equipment When does the equipment transfer the state? How to poll the equipments that is sleep mode

September, 2000

Slide 7

John M. Kowalski,

8 Appendix: Formats for 1394/IEC61883-4

Appendix: Formats for 1394/IEC61883-4

September, 2000

Slide 8

John M. Kowalski,

9 1394 MPEG2-TS Transfer

1394 MPEG2-TS Transfer

MPEG2-TS transfer sequence is defined in IEC61883 standard. Source packet header (4bytes) is applied to each transport stream (TS) packet (188bytes). (Source packet header consists of Reserved field (7bits), cycle count (13 bits), cycle_offset (12 bits). These field is used as time stamp.) Source packet (comprising source packet header and TS packet) is divided to each data block (24bytes). Several data blocks are put into one isochronous packet. Common Isocrhonous Packet (CIP) header and IEEE1394 header are applied to each isochronous packet. The isochronous packet is transferred. Empty packet (composed only CIP and 1394 Header) is transferred when there is no data to be transferred.

September, 2000

Slide 9

John M. Kowalski,

10 1394 MPEG2-TS Transfer (cont

1394 MPEG2-TS Transfer (cont

188bytes

188bytes

Example of MPEG2-TS data transfer defined in IEC61883 is shown below.

TS Packet

Timestamp

Header

125us

Empty Packet

September, 2000

Slide 10

John M. Kowalski,

11 TS Packet Transmission Rate

TS Packet Transmission Rate

Maximum jitter is assumed to be about 311 ms on transmit, and 50ms from real time interface, from IEC 61883-4

TS Packet / cycle

Transmission rate (Mbps)

1/8

1,504

1/4

3,008

1/2

6,016

1

12,032

2

24,064

3

36,096

4

48,128

5

60,160

September, 2000

Slide 11

John M. Kowalski,

12 Header

Header

CIP header and 1394 header is applied to each isochronous packet. CIP header is defined in IEC61883 standard, 1394 header is defined in IEEE1394 standard. The source packet header is applied to each TS packet.

IEEE1394 isochronous header

CIP header

Data

Source packet header (shown in each TS packet)

data_CRC

September, 2000

Slide 12

John M. Kowalski,

13 1394 Header

1394 Header

The shaded field is defined by IEEE1394 (4 bytes/line).

data_length: data block payload length 2 bytes tag: high level label for format of data. 012 is defined as CIP header. channel: isochronous channel 6 bits. tcode: transaction code. Ah is defined as isochronous data block. sy: Application-specific control field. (4 bits synch. code)

data_length

tag

channel

tcode

sy

header_CRC

CIP header

Data

data_CRC

September, 2000

Slide 13

John M. Kowalski,

14 CIP Header

CIP Header

The shaded field is defined by IEC61883. (4 bytes/line)

1394 isochronous header

00

SID

DBS

FN

QPC

s

r

DBC

10

FMT

FDF

Data

data_CRC

SID: Sender node ID DBS: Data Block Size FN: Fraction number QPC: Quadlet padding count SPH(s): Source Packet Header

DBC: Data Block Counter FMT: Format ID FDF: Format Dependent Field r: Reserved

September, 2000

Slide 14

John M. Kowalski,

15 CIP Header (MPEG2-TS)

CIP Header (MPEG2-TS)

Each field is defined as the followings for MEPG2-TS transfer. SID: depends on configuration DBS: 000001102 (6quadlets = 24bytes) FN: 112 (8 data blocks in one source packet) QPC: 0002 (no padding) SPH: 1 when source packet header is present DBC: 0 … 255 FMT: 1000002 (Format type of MPEG2-TS) FDF: For MPEG2-TS transfer, most significant bit is defined as TSF, others are reserved. TSF indicates a time shifted data stream (1: the stream is time shifted.).

September, 2000

Slide 15

John M. Kowalski,

16 Source Packet Header

Source Packet Header

4bytes Source Packet Header is shown below. The time stamp in the source packet header is used by isochronous data receivers for reconstructing a correct timing of the TSPs at their output.

Reserved

cycle count

cycle_offset

7bits

13bits

12bits

September, 2000

Slide 16

John M. Kowalski,

17 DV Format (SD-DVCR)

DV Format (SD-DVCR)

DV video, audio data consists of 80 bytes (Digital Interface) DIF block. 1 DIF sequence consists of 150 DIF blocks. 1 video frame consists of 10 DIF sequences (in case of NTSC) See: http://www.chumpchange.com/parkplace/Video/DVPapers/dv_formt.htm ._

…………

…………

480bytes

80bytes

0

H0

SC0

SC1

VA0

VA1

VA2

A0

V0

V1

V2

V3

V4

1

DIF Sequence 0

V129

V130

V131

V132

V133

V134

H0

SC0

SC1

VA0

VA1

VA2

DIF Sequence 9

249

V129

V130

V131

V132

V133

V134

September, 2000

Slide 17

John M. Kowalski,

18 1394 DV Transfer (for reference)

1394 DV Transfer (for reference)

480bytes

480bytes

480bytes

480bytes

Example of DV Data transfer defined in IEC61883 is shown below.

Header

Empty Packet

125us

September, 2000

Slide 18

John M. Kowalski,

19 DV Format Rate (SD-DVCR)

DV Format Rate (SD-DVCR)

DV video rate is calculated by the followings. DV data size of one video frame 80 (byte/DIF block) * 150 (DIF block/DIF sequence) * 10 (DIF sequence/video frame) = 120,000 bytes 120,000 (bytes/video frame) * 29.97 (frame/s;NTSC) = 3.43 (MB/s) = 27.44 (Mbps) (1M = 1024*1024)

September, 2000

Slide 19

John M. Kowalski,

20 CIP Header (SD-DVCR)

CIP Header (SD-DVCR)

IEEE1394 isochronous header of DV transfer is the same as the one of MPEG2-TS. In CIP header of DV transfer, the SYT field is defined. Other fields are the same as MPEG2-TS. Source packet is not used since time stamp is applied as SYT field.

1394 isochronous header

00

SID

DBS

FN

QPC

s

r

DBC

10

FMT

STYPE

r

SYT(Timestamp for DV data)

Data

FDF field

data_CRC

September, 2000

50/ 60

Slide 20

John M. Kowalski,

21 CIP Header (SD-DVCR)

CIP Header (SD-DVCR)

Each field is defined as the followings for SD-DVCR transfer. SID: depends on configuration DBS: 011110002 (120quadlets = 480bytes) FN: 002 (Not divided) QPC: 0002 (no padding) SPH: 0 (no source packet is used) DBC: 0 … 255 FMT: 0000002 (Format type of SD-DVCR) FDF 50/60: Field system (0: 60 field, 1: 50 field) STYPE: Signal type of video signal. SYT: Time stamp of the video frame synchronization.

September, 2000

Slide 21

John M. Kowalski,

22 DV Format Rate of 1394 transfer

DV Format Rate of 1394 transfer

The DV data is transferred in every 125us. The transferred DV data consists of 1394 header (12 bytes), CIP header (8 bytes) and DV data (480 bytes). DV data packet size = 12+8+480 = 500 (bytes) 500 (bytes) / 125 (us) = 4(MB/s) = 32 (Mbps) (1M = 1024*1024)

September, 2000

Slide 22

John M. Kowalski,

«MPEG-2 High Rate Video over 1394 and Implications for 802»
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