MPEG2 Highdefinition Television HDTV over IP

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MPEG2 High-definition Television (HDTV) over IP
Graduate Workshop on Networking 2005

• 2005.10.20
• Joonbok Lee
• KAIST
• jblee_at_cosmos.kaist.ac.kr

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Table of contents

• 1. Introduction
• 2. High-definition digital video over IP
• 3. Experiments
• 4. Conclusion

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1. Introduction

• 1.1 Application of Next Generation Internet
• High bandwidth application
• Gilders Law Bandwidth grows 3x/year

Basic Service Email File Transfer Telnet
News WWW
Advanced Service Transaction Video/Audio
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1.2 High Quality Digital Video Technologies
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1.3 HDTV over IP Technology

• Uncompressed HDTV over IP
• 11.5 Gbps (using 2GbE or 10GbE)
• Low delay (100msec)
• Application interactive application (Video
  conference, Remote performance)
• Systems are developed by ResearchChannel, USC
  ISI, KAIST, GIST, NTT
• MPEG2 compressed HDTV
• 2080Mbps
• Encoding/decoding delay (12sec)
• Application remote seminar with limited
  interaction, VOD
• H.264 compressed HDTV
• 10Mbps
• Encoding/decoding delay (23sec)
• Application VOD

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2. High-Definition Digital Video over IP

• 2.1 HDV Format
• High-Definition Digital Video Recording and
  Playback on a DV cassette tape
• MPEG-2 Video in TS (Transport Stream)
• Element Stream TypeVideo MPEG2 (ISO/IEC
  13818-2)
• Audio MPEG1 (ISO/IEC 11172-3)
• 20 Mbps 30Mbps

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2.2 HDV over IP system
HD Camcorder
HD Display
TS Packets
MPEG-2 TS

IEEE1394Interface
IP Network


Packetizer and MPEG2 Decoder
Packetizer

RTP Packets
Sender
Receiver
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2.3 Related Internet Standard

• RFC 1889 RTP A Transport Protocol for Real-Time
  Applications
• RFC 2250 RTP Payload format for MPEG1/MPEG2
  Video
• RTP Payload contain integral number of MPEG
  transport packet (188byte).
• Suggest several MPEG picture fragmentation rules.
• RTP Header fields for MPEG2 Video

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2.4 RTP Packet Format
Group Of Pictures
Picture
Slices
PES

Variable length
TS Packets
RTP Header

Fixed Size 188Byte

• RTP Packet contains several TS Packets according
  to MTU size.
• Do not divide TS packet.
• But if new slice is begin, make another RTP
  packet
• Reduce effect of packet loss.
• Reduce decoding overhead.

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2.5 Software Structure

• Sender Receive MPEG2-TS stream from JVC GR-HD1
  using IEEE1394 interface, and then make RTP
  packet.
• Receiver Depacketize RTP packets, and then
  decode and show MPEG2-TS stream.

IEEE1394 Interface
RTP Packetizer
Sender
MPEG2Decoder
MPEG2-TSDemuxer
Video Renderer
Receiver
RTP Depacketizer
Traffic Shaper
AudioRenderer
Audio Decoder
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2.6 Traffic Shaper

• IP network is best-effort service.
• Packet loss, jitter and out-of-order packets
• Traffic Shaper
• Circular Queue between RTP depacketizer and
  MPEG-2 Demux.
• Reduce effects of jitter and out-of-order
  packets.
• But increase delay.

TS Packets 35
20
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Sleep during constant time
Wait until receiving RTP Packet
TS Packets37
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Parse PSI information and calculate the time to
sleep
Store to Circular Queue
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TSPackets 23
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TSPackets 22
Read from Circular Queue
Depacketizing
read
Circular Queue
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3. Experiments
3.1 Experiments in real environment

• Experiments between KAIST and Cernet over
  IPv4/IPv6

20Mbps MPEG2 HDTV Stream
20Mbps MPEG2 HDTV Stream
155Mbps
APIIKR-CN Link
CERNET( China Education and Research Network)
KOREN(Korea advanced Research Network)
KAIST
Tsinghua University

• We succeed to transmit and receive using IPv4,
  but failed using IPv6. Its main reason is the
  IPv6 performance of router which has only IPv6
  software forwarding engine.

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3.2 Interarrival jitter with traffic shaper

• Jitter can have a significant impact on both the
  video quality and MPEG2 decoder performance

It reduced the jitter to about 5ms. ( to minimize
the effects of jitter, 4msec is recommended)
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4. Conclusion

• We develop and experiment HDV over IP system.
• 20Mbps 720p, 1080i stream.
• Simple to setup.
• Supports IPv4, IPv6, Unicast and Multicast.
• To reduce effects of packet loss, jitter and
  out-of-order packet, we use circular queue. And
  it can reduce the jitter to 5 msec.
• Applications
• Remote Lecture
• Cyber Performance (no interact)
• Parts of Video Conferencing
• Now we are working on HDTV for million subscriber
• Network Infrastructure (multicast, content
  distribution, )

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