VIDEO CONFERENCE. Alessandro Benni & VIDEO COMMUNICATIONS. Bologna, Videorent srl - Video & Multimedia Branch

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2 VIDEO CONFERENCE & VIDEO COMMUNICATIONS Alessandro Benni Videorent srl - Video & Multimedia Branch Bologna, 2007

3 Today s lesson will cover What is Video Conference? Why Video Conference? History of Video Conferencing How it works? What about the Network? Requirements for Video Conferencing Endpoints Video Conferencing Etiquette Key points of Video Conference Limitations of Video Conferencing Video communication on-demand What about MISCBO?

4 What is Video Conference? It s a communication across long distances with video and audio contact that may also include graphics and data exchange. Digital video transmission systems typically consist of camera, codec (encoder-decoder), network access equipment, network, and audio system. Bologna New York

5 What is Video Conference? 2 It s a medium where two or more people at different locations can meet face-to-face in real time. VC can Offer new possibilities to connect with guest speakers and experts and can make relevant learning opportunities more accessible.

6 Why Video Conference? Save money (Avoid flights, hotel, transfers) Save time (Provides a focused, precise, and concise communications tool; people don t waste time videoconferencing as they often do in faceto-face meetings) Build relationships Communicate face to face (where it would otherwise be impossible) Teach & Learn Collaborate

7 Why Video Conference? 2 In many situations, video conferencing is the next best thing to a face to face meeting.

8 History of Video Conference The first video conference The first public videoconference was held in April 1930, between AT&T headquarters and their Bell Laboratory in New York City. H.320 introduced in Not IP Expensive Managed environment H.323 introduced in 1996 IP Lower cost Less managed SIP (Session Initiation Protocol) Used by most voice over IP solutions

9 How it works? 5 simple steps (bi-directional) CAPTURE ENCODE PUSH&PULL DECODE VIEW NETWORK

10 How it works? 2 CAPTURE / VIEW Capture audio/video Live video of conference & meeting from camera Live video from surgery room from surgical equipment Pre recorded video clips from VCR or PC Capture PC screen Power Point presentation Listen & View in auditorium Projectors, LCD or plasma screen, speakers

11 How it works? 3 ENCODE / DECODE This role is played by an HW/SW called CODEC Capture and mix audio/video signal Compress/Encode signal in international standards H263/H264/MP4/G711/G722 Initiate and negotiate connection H320/H323 Push & Pull packets from Network ISDN H320 or IP/SIP H323 Decompress/Decode signal Allows you to use standard audio/video output

12 How it works? 4 PUSH & PULL TO/FROM NETWORK This role is played by an HW/SW called CODEC The encoded audio/video is disassembled in packets & BIT These packets move around the network Packet in straight order arrive to other codec Codec decode packest in A/V signal BUT WHAT ABOUT THE NETWORK?

13 What about the network? The network is the medium of video communication For videoconference: 3 types of network ISDN (max 768 Kbps) Digital telephone lines with allocated bandwidth IP (max 3Mbps) LAN or WAN (internet), can be also an ADSL o Fiber cable connection V35 (no limit bw) Satellite standard, high dedicated bandwidth Too expensive and too hard to find

14 What about the network? ISDN Integrated Services Digital Network ISDN lines come in channels called B channels Each circuit = 64k (must be in pairs) Used standard is H.320 Dial-up Service Typical telemedicine systems use six (to obtain a reasonable quality) + Allocated Bandwidth World standard Easy to find Fast configuration - High usage cost Maximum quality 768K H320 is old Telecom companies

15 What about the network? IP Internet Protocol IP is standard protocol for LAN and Internet Used standard is H.323, newer than H320 Supports Hi-quality video compression Typical telemedicine systems use six (to obtain a reasonable quality) + No cost for connection Users grow rapidly Decentralized control HD & High quality ready - No quality of service Need a powerful connection Difficult configuration Need IT knowledge

16 What about the network? Compression & Bandwidth And more 1,5 Mbps is like satellite TV 4 Mbit is like a DVD

17 Requirements for video conference Endpoints (for you and remote party) Video codec, Set top Box or Software IP connectivity or ISDN Lines At least 256K for still conference At least 384K for Motion videos At least 512K for surgical videos Good network status (in case of IP) No NAT or NAT workaround No firewall OR routed through firewall

18 Endpoints Desktop/Software Endpoints Allow you to receive to your PC video conference stream and send video signal from webcam Conference room unit Video codec with camera, works standalone with a normal TV. Allow you to send & receive audio/video & PC signal Classroom unit Complex video codec with many A/V inputs. Allow you to build videoconference & multi video conference infrastructure 250 ca ca ca.

19 Tips for Getting Started Test every videoconference location thoroughly. Testing will help to identify and address equipment and networking issues in advance. Testing gives end users additional experience with the equipment. Testing allows the videoconferencing experience to be successful and positive for users. Murphy s Law: If something can go wrong, it will.

20 Videoconferencing Etiquette Plan your videoconference Send the agenda and handouts in advance Allow a few minutes for call start up and shut down time Stick to time limits Remember to mute the microphone (when unused) Take turns speaking and allow time for audio delay Avoid Can You hear me? Can You hear me? Check camera lighting and video quality Prepare your powerpoint in a simply & clear way Use a location banner

21 Video conference Key points Save money & Time Avoid flights, travel, jetlag, transfers etc. High quality With good equipment and good network connectivity you can reach a very good quality E-Learning Video conference allows you to make and watch remote presentations and lessons Create partnerships Helps you grow and consolidate partnerships and distance collaboration

22 Video conference Limitations Limitations are linked to network troubles Firewalls Port Blocking Bandwidth NOT! Dial Up Modem MAYBENAT Hidden IP Address Cable Modem/DSL Yes!!! Internet2

23 About MISCBO Surgical room Policlinico S.Orsola-Malpighi Tech room MISCBO auditorium Other centres w orldwide

24 About MISCBO 2 MISCBO IRRCAD (Strasbourg FR), 2007

25 About MISCBO 3

26 About MISCBO 4

27 About MISCBO 5 On demand videos Easy to view Large compatibility No particular connections needed No space/time limitations Full play/pause control High quality Good teaching & learning possibilities

28 That s all Folks! Thanks a lot for your attention Infos? [email protected]