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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 code Standards based Runs on multiple UNIX platforms Mac OS X Redhat Solaris
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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 code • Standards based • Runs 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 • HTTP • FTP • RTP • 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 QoS • Helps 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/IP • Similar to HTTP • Can be extended as HTTP is extended • Maintains state • Server and Client can make requests • Data 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
Multicast • One to Many • Client joins a multicast session • SDP file
SDP File(Session Description Protocol) • Group Address • Port number • Commonly put on Webserver to announce multicasts • Codecs • Tracks
Reflector • RTSP server • Accepts Media stream • Multicast • Outputs unicast streams
Receiving Stream • Open file that contains streaming tracks • Open sdp file • Open 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 controls • Header reconstruction for media tracks • Precalculates data for server • Off loads computation