QuickTime

The Joy of Streaming!

QuickTime Streaming Server

Allows for real time delivery of media over a network. intranet internet

Content can be prerecorded or broadcasted live.

QTSS

Open source codeStandards basedRuns on multiple UNIX platforms Mac OS X Redhat Solaris FreeBSD

Compatible Streaming Formats

Video QuickTime AVI

Audio AIFF/AIFC System 7 Sound Sound Designer II µLaw(AU) Wav

Compatible Streaming Formats

Midi Karaoke Midi Standard Midi

Recommended Compression

Video Sorenson Video H.263 H.261 Motion JPEG A

Recommended Compression

Audio MP3 Qdesign Music Codec

instrumentals QualCOMM Pure Voice

Voice only DVI 4:1 Alaw 2:1 µLaw 2:1 16-bit raw

Streaming Protocols

HTTPFTPRTP Realtime Transfer Protocol

RTCP Real Time Transport Control Protocol

RTSP Real Time Streaming Protocol

RTP

Realtime Transport Protocol 1 minute of video is sent in 1 minute Packets are time stamped Live content and prerecorded can be streamed Uses UDP

Transport-independent

2 parts Thin protocol that supports real-time

applications, security, and content identification Control part that uses RTCP

RTCP

Support for real-time conferencing Support for real-time conferencing Source identification Multicast-to-Unicast translators Offers Quality-of-Service information Synchronization of different media

streams

Quality of Service

Routers provides a level of QoSHelps with jitter and latency Required by some real-time and

interactive traffic.

All networks do not provide the same level of QoS

RTSP(Real Time Streaming Protocol)

Uses TCP/IPSimilar to HTTP Can be extended as HTTP is extended

Maintains stateServer and Client can make requestsData is transmitted “Out-of-band” RTP RDP

Real Data Transport -- RealNetworks

Unicast

Unicast One to One Client sends request using RTSP Server Responds with streaming

session information. How many streams, what types, codecs

they use Streams are then sent to the client via

RTP

Unicast

Multicast

One to ManyClient joins a multicast session SDP file

Multicast

SDP File(Session Description Protocol)

Group AddressPort numberCommonly put on Webserver to announce multicastsCodecsTracks

Reflector

RTSP serverAccepts Media stream Multicast

Outputs unicast streams

Receiving Stream

Open file that contains streaming tracksOpen sdp fileOpen url rtsp://nova.it.rit.edu/

Setting up the Movie

Pre-prerolling Establishing RTSP connection Establishing RTP stream connections

Prerolling Allocate buffers Open media handlers

Hint Track

Unicast has VCR like controlsHeader reconstruction for media tracksPrecalculates data for server Off loads computation

Serving Hinted Movie