Design and implementation of IPv6 multicast based

High-quality Videoconference Tool (HVCT)

2003. 8. 28

Tae-wan You, Seoul National University, Korea

Outline

• HVCT and Features• Software design • Implementation Details• Experimental result• Future work

HVCT & Feature

HVCT

• a High-quality Video Conferencing Tool • Works on Windows 2000, SP 1 with

IPv6 stack• Microsoft DirectX 8.0 or Higher• Video data be en/decoded using

MPEG-4 Codec – Video : 320x240 pixels, 15fps

• Audio data be en/decoded using MP3 Codec– Audio : 44kHz, 16bit, 2 channel

Feature (1/2)

• IPv6 capability– Working on MSR and MSDN IPv6 stack

• Multicast– Efficient use of network resources via

multicast

• Support– High-quality multimedia data using MPEG4

codec and MP3 codec– Show a statistics that be measured traffic– Can chat using multicast

Feature (2/2)

• Main dialog of HVCT– Show screen ofparticipants

• Traffic monitoring– total number of bytes received– packets lost– packets misordered– represent a bandwidth using graph

• Chat with participants by multicast protocol

Software Design

Decoding ManagerEncoding Manager

Software Components

MPEG4 Video Software Encoder

MP3 Audio Software Encoder

A/VMUX

A/VDEMUX

MPEG4 Video Software Decoder

MP3 Audio Software Decoder

RTP overUDP/IPv6

Network Manager

Software Components

• Encoding Manager– Make an one stream with video data, which be encoded using MPE

G4 codec and audio data, which be encoded using MP3 codec.

• Network Manager– Add RTP header with stream and send it as udp packet to multica

st address for IPv6– After receive a packet, remove RTP header and pass data to DM

(Decoding Manager)

• Decoding Manager– decode the each of the stream and play both audio and video usin

g Render filter

Software ArchitectureUser Interface

RTP/RTCP & Buffer

DirectShow

Filter(Capture)

DirectShowFilter

(Display1)

DirectShow

Filter(Display2)

DirectShow

Filter(Display3)

SocketThread(for send data)

SocketThread2(for receive data)

Control Message

Data Stream

Implementation Details

Multimedia Data Transfer

Sender ComponentCaptur

e Driver

Sound Driver

MPEG4 Encode

r

MP3 Encode

r

Video Tee

Audio Tee

MPEG4 Decode

r

MP3 Decode

r

Video Render

er

Sound Driver

Audio/VideoMUX

RTP/RTCP

UDP/IPv6

IPv6 Multicast NetworkIPv6 Multicast Network

Video Stream

Audio Stream

A/V Muxed Stream

Receiver ComponentVideo Source

Audio Source

MPEG4 Decode

r

MP3 Decode

r

Video Render

er

Sound Driver

Audio/VideoMUX

RTP/RTCP

UDP/IPv6

IPv6 Multicast NetworkIPv6 Multicast Network

Video Stream

Audio Stream

A/V Muxed Stream

Implementation Details

RTP/RTCP Data Transfer

RTP, RTCP Library

• The library be implemented on the basis of RFC 1889– Define data type by structure in C++– RTP, RTCP, RR, SR, SDES etc.– Made functions that can achieve

accomplishments that is supported by RTP, RTCP using defined data types

InitRtp

SetRtpSdes

SendRtpBye

done

SendRtpCtrl

SendRtpData

OnRecvRtp

UpdateRtp…

…

Create Session

Participantdb

Create db

Rtp socket Rtcp socket

MySSRC

APAN-SNU138-317

Multicast data/ctrl

KORENSEOUL AP

IPv6 Host

IPv6 Router

Join Session & Start Talk

Join Session RTCP (RR,SDES) RTCP

(RR,SDES)

Start Send Data

RTP (MPEG, MP3 payload)Start Playing / Participant 1 := Active Source

RTCP (SR,SDES)

RTCP Interval of

Participant1

RTCP

(RR,SDES)

Participant 1 ff0e::1:2:3 / 5002Participant 2

RTP (MPEG, MP3 payload)

Experimental result & Future work

Experiment environment

ATM S/WETRI

ATM S/W

Daejeon AP

ATM S/W

Seoul APATM S/W

SNU APATM S/W

PC Router 1

PC Router 2

Host 1 Host 2

Subnet A (ETRI) Subnet B (SNU)

Result – bandwidth

• Video by MPEG-4 Codec– Input data : 15 frame per second, I420

format– Output data : 350 ~ 400Kbps

• Audio by MP3 Codec– sample 16bit, two stereo, sampling rate

44.1kHz• 16 * 141000 * 2 =~ 1.3 Mbps

– Output data : 56 kbps

Bandwidth compare with vic

• UCL’s vic– H.261, 10fpsRGB24 format

• HVCT– MPEG4, 15fpsI420 format

Result – delay (1/2)

• Video Delay

Result – delay (2/2)

• Audio Delay

Future Work

• Reduce end-to-end delay• Experiments with other conferencing tool

– VIC from UCL, ISABEL from Agora Systems etc. – Performance Test

• You can get more information from http://mmlab.snu.ac.kr/~hvic

Thank You !! &

Any Questions ?