T.Sharon-A.Frank 1 Multimedia Various Applications

2 T.Sharon-A.Frank Contents , MM-Mail and Internet Fax Voice Response Systems Computer Messaging Services A/V Streaming Video On Demand (VOD) Video/Multimedia Conferencing Virtual Reality (VR)

3 T.Sharon-A.Frank Download A/V vs. Streaming A/V Copy to system Download and then play A/V View/Listen locally Special Protocol Streaming A/V View/Listen while loading

4 T.Sharon-A.Frank Playing media over Web via download

5 T.Sharon-A.Frank Streaming media using Web and Media server

6 T.Sharon-A.Frank Audio/Video Streaming A technique for transferring data such that it can be processed as a steady and continuous stream. Data can be displayed before entire file has been received. If data arrives quicker than display, need a buffer. If data arrives slower than display, poor quality, jerky display.

7 T.Sharon-A.Frank Use of buffering with Media server The media player buffers input from the media server and plays from the buffer rather than directly from the network.

8 T.Sharon-A.Frank Multimedia Streaming Delivering a multimedia file from a server to a client – the delivery occurs over a network. There are two different types of streaming: 1.Progressive download – the client begins playback of the multimedia file as it is delivered where the file is ultimately stored on the client computer. 2.Real-time streaming – the multimedia file is delivered to – but not stored on – the client’s computer.

9 T.Sharon-A.Frank Real-time Streaming There are two types of Real-time streaming: 1.Live streaming – used to deliver a live event while it is occurring. 2.On-demand (stored) streaming – used to deliver media streams such as movies, archived lectures, etc. The events are not delivered in real-time.

10 T.Sharon-A.Frank Audio/Video Applications 1)Streaming On-demand audio/video: Famous radio broadcasts, full-length movies (VOD), prerecorded TV shows, music video clips, archived class lectures, etc… 2) Streaming Live audio/video: Internet radio talk show, live webcasts, etc… 3) Real-time interactive audio/video: Internet telephony (VoIP), video conferencing, MM conferencing, distributed interactive worlds, etc…

11 T.Sharon-A.Frank Video On Demand (VOD) TV Guide Set-Top Box or Desktop HSN Switches Video Redistributers Video Servers

12 T.Sharon-A.Frank VOD using different local distribution technologies (a) ADSL (b) Cable TV

13 T.Sharon-A.Frank Near Video On Demand (N-VOD) Near video on demand can have a new stream starting at regular intervals, in this example every 5 minutes (9000 frames).

14 T.Sharon-A.Frank Near Video On Demand (N-VOD) Time Movie C Movie B Movie A Transmission of AABBACBC Subscriber requests for movies

15 T.Sharon-A.Frank Content Distribution Networks (CDNs) Stream large files (e.g., video, MM presentations) from single origin server in real-time. Solution: replicate content at hundreds of servers throughout Internet: –Content downloaded to CDN servers ahead of time. –Placing content “close” to user avoids impairments (loss, delay) of sending content over long paths. –CDN server typically in edge/access network. –Uses DNS system to re-route requests.

16 T.Sharon-A.Frank How do CDNs work? CDN (e.g., Akamai) customer is the content provider (e.g., CNN). CDN replicates customers’ content in CDN servers. When provider updates content, CDN updates all the servers. origin server in North America CDN distribution node CDN server in S. America CDN server in Europe CDN server in Asia

17 T.Sharon-A.Frank CDN Distribution Tree

18 T.Sharon-A.Frank Multimedia Conferencing

19 T.Sharon-A.Frank What is it used for? Social Encounters Job Interviews Business Meetings Distance Learning Medical Consultation

20 T.Sharon-A.Frank Conference Types Chat Conference (IRC, Chat) Audio Conference (WebPhones) Video Conference (VC Tools) –Bi-party Conference –Multiparty Conference (Reflector, MeetingPoint): »Group Communication »Needs Floor Control

21 T.Sharon-A.Frank Audio Conference Why use the POTS when you can get it so much better on the Internet?

22 T.Sharon-A.Frank Video Conference IVS-Rendezvous

23 T.Sharon-A.Frank Multimedia Conference via Skype

24 T.Sharon-A.Frank The Meeting Room Conference

25 T.Sharon-A.Frank VC Hardware Cameras Screens Speakers and Microphones Other Aids (Electronic Board, Remote Control)

26 T.Sharon-A.Frank VC Software/Tools Chat Video/Audio tools Whiteboard Data/File Transfer Application Showing Application Sharing

27 T.Sharon-A.Frank Whiteboard

28 T.Sharon-A.Frank TelePresence Conference Set of technologies allowing a person to feel as if they were present, at a location other than their own one. Requires good lighting and screens installed with speakers. Transmits the user's position, movements, and voice to the remote location. Enables the same transfer for both ends, allowing interactive dialogue. Delivers an 'in person' experience, allowing meetings without travelling.

29 T.Sharon-A.Frank An Example TelePresence Conference

30 T.Sharon-A.Frank Virtual Reality (VR) Usage Create an illusion of imagined reality or augmented reality: Entertainment Training –Flight simulators –Driving simulators

31 T.Sharon-A.Frank Virtual Reality Examples

32 Strictly, an immersive sensory experience of a synthetic world –Head-mounted displays, data gloves, haptic interfaces, etc. More modestly, 3D graphics that can be explored: –Draggable panorama, objects that can be moved round –VRML, QuickTime VR. Virtual Reality

33 T.Sharon-A.Frank VR CAVE Example

34 T.Sharon-A.Frank Augmented Reality

35 T.Sharon-A.Frank Mediated Reality

36 T.Sharon-A.Frank Mediated Reality Examples