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9 dec 99 EV @ SURFnet/SEC Seminar 1
Streaming technologie
Egon VerharenSURFnet Innovatie [email protected]
•Inhoud•Definities•Formaten•Protocollen•Distributie•Architecturen•Codecs•Servers•Clients•Innovatie Projecten•Toekomst•Demo inleiding
9 dec 99 EV @ SURFnet/SEC Seminar 2
Definities• “Streaming” is buzz-woord.
– Is een bijvoegelijk naamwoord
• Focus: Streaming MEDIA• Definities terug te voeren op verschillende
aspecten:– Push vs. Pull– Client-oriented vs. server-oriented– on-demand vs. live
– Streaming media is the simultaneous transfer of video, audio and data [multimedia data] so that it is received as a continuous real-time stream
– Streamed data is transmitted by a server application and received and displayed in real-time by client applications. These applications can start displaying video or playing back audio as soon as enough data has been received and stored in the receiving station's buffer
9 dec 99 EV @ SURFnet/SEC Seminar 3
Formaten• Aspecten:
– Bitrates (constant, variable)– Framesize– QoS
• Bandbreedte (bij eind-gebruiker) • Real SureStream, simulcast
• Standaarden– ISO/IEC (int.l. org for standardization/int.l. electrotechnical
commission)• Moving Pictures Experts Group (ISO/IEC JTC1/SC29/WG11)
– ITU (int.l. telecommunication union)• Series H (video), Series G (audio) (ITU-T SG16)
9 dec 99 EV @ SURFnet/SEC Seminar 8
Protocollen• Streaming Media Protocols are protocols that
are being used to support the real-time delivery of multimedia data
• TCP vs. UDP• HTTP
– progressive download• RTP
– real time protocol– UDP– payload
9 dec 99 EV @ SURFnet/SEC Seminar 9
Protocollen (cont. RTSP)• RTSP
– Real Time Streaming Protocol• designed to be an open standard aims to provide an
extensible framework to enable controlled delivery of real-time data, such as audio and video.
• Denk: videocontrole (play, pauze, stop, back, forward)
– http://www.ietf.org/rfc/rfc2326.txt
9 dec 99 EV @ SURFnet/SEC Seminar 10
Distributie• Scenario’s
– Broadcast vs. Groupcast vs. Personcast (Video-on-demand)
• Techniek– Unicast– Multicast
• cookbook• contact SURFnet Netwerkdiensten ([email protected])
9 dec 99 EV @ SURFnet/SEC Seminar 11
Architecturen• RealMedia
– codecs: RealVideo, RealAudio
– streaming formaat: RealVideo, RealAudio, met plugins (bijv. BitCasting) MPEG1, MP3
– SureStream: multiple bitrate encodings, bandwidth negotiation
– RealText, RealPix– SMIL (Synchronized
Multimedia Integration Language)
– Standaarden: RTSP, RTP (RDP)
9 dec 99 EV @ SURFnet/SEC Seminar 12
Architecturen (cont.)• Apple Quicktime
– ondersteuning vele codecs• streaming RTP
payloads; Sorensen: VBR, CBR
– streaming formaat: Quicktime (hinted movies)
– plug-in architectuur– tracks & effects &
interactivity– standaarden: RTSP, RTP– zie demo
9 dec 99 EV @ SURFnet/SEC Seminar 13
Architecturen (cont.)• Microsoft Windows Media
Technologies– NetShow,
DirectShow/ActiveMovie, Video for Windows
– codecs: Windows Media Audio (WMA), MPEG-4 v3, ACELP (voice)
– streaming formaat: ASF (advanced streaming format)
– Multi-Datarate Encoding, Intelligent Transmission, Media rights
– standaarden: ??; WMM– office integratie !! (bijv.
streaming powerpoint)– Meest ‘compatible’ client (player)
9 dec 99 EV @ SURFnet/SEC Seminar 14
Codecs• Codecs
– MPEG1, MPEG2, MPEG4 (zie notes)– MP3 = MPEG-1 audio layer 3 – Qualcomm PureVoice– Qdesign Music (stereo audio for dialup data rates en fast
processor)– a2b (AAC, high fidelity, faster data rates, encryption)– liquid audio (arch., AAC, hifi, encryption, licensing,
watermarking)– java based: emblaze, GTS– Sorensen (video, both dialup and cable modem data rates)– Vivo (VIV), Vxtreme (VXF), VDOnet
– http://www.terran.com/CodecCentral/
9 dec 99 EV @ SURFnet/SEC Seminar 15
Servers• Aspecten
– opslag– media pomp– netwerk (bandbreedte)– on-demand vs. live– asset management
• Voorbeelden– “Low end”
• Apple Quicktime• Real G2• Microsoft Windows Media
9 dec 99 EV @ SURFnet/SEC Seminar 16
Servers (cont. Voorbeelden)– “high end”
• FVC.COM I-Studio• Cisco IP/TV
– standaarden ondersteuning
• IBM Videocharger– Digital Library; architectuur; interactiviteit– standaarden ondersteuning
• SGI Mediabase• Ncube/Oracle MediaCUBE/Videoserver• ...
• Frameworks– SUN & IBM Java media framework
– unified architecture for the playback, synchronization, capture, transmission and transcode of media -- including streaming audio and video -- across most major operating systems
9 dec 99 EV @ SURFnet/SEC Seminar 17
Clients• Aspecten
– Synchronisatie– Buffer– Multicast
• Voorbeelden– FVC.COM I-viewer– Cisco IP/TV viewer– IBM Videocharger client– Apple Quicktime client– Microsoft Windows Media Player– Mbone tools
• SDR, Vic, Rat, …
9 dec 99 EV @ SURFnet/SEC Seminar 18
Innovatie Projecten• VIP
– partners: TI, NOB Interactive, IBM, SURFnet– metadata, searching & indexing– watermarking, copyright protection– accounting & billing– distributie (multicast, QoS)
• SURFnet-TV– now
• FVC.COM I-studio– MPEG1 en H.261/PCM/text streaming– live events en TV
9 dec 99 EV @ SURFnet/SEC Seminar 19
Toekomst projecten• SURFnet-TV
– netcasten van voor (een deel van) de doelgroep interessant materiaal (wetenschapsTV)
– meerdere kanalen– Scheduled (Electronic Program Guide) en Live– doorgifte soortgelijke kanalen (bijv. Funet-TV, Canarie)
• High Quality– DV, HDTV experimenten
• Reverse Content Provision
• Altijd op zoek naar interessante projecten/partners. Maak jezelf bekend svp.
9 dec 99 EV @ SURFnet/SEC Seminar 20
Toekomst• Kwaliteit
– DV -> HDTV
• Inhoud– 3D (bijv. VRML, QuicktimeVR)
• Codecs– fractal– VBR
• Standaarden– RTP/RTSP, incl. authenticatie, MPEG4 & MPEG7
• Meer streaming servers/clients– betere toegangsnetwerken– Networked Video (IP networks)
– media & asset management
9 dec 99 EV @ SURFnet/SEC Seminar 21
Demo inleiding
Seminar streamen via Real G2 (unicast en multicast SureStream) en SURFnet-TV (I-studio; MPEG1)