CP2022 - Multimedia Computer Communication

1. CP2022 - Multimedia Computer Communication Lecture 1 - Communication CP2022 - Multimedia Internet Communication

2. Module teaching team • Module leader – Prof. Andy Sloane • Room MI114 - Extn. 1445 • Email A.Sloane@wlv.ac.uk • Tutorial group lists will appear on the module web page in Week 2 CP2022 - Multimedia Internet Communication

3. Outline Summary • All details are available on the module Website http://www.scit.wlv.ac.uk/~cm1950/CP2022/ • Recommended course text Internet Multimedia by Andy Sloane Palgrave, 2005 ISBN 1-4039-3413-4 CP2022 - Multimedia Internet Communication

4. Weekly schedule • 3-hour block • 1.5 hour Lecture • 1.5 hour Workshop (weeks 1-6) • or Tutorial (Weeks 7-12) • See schedule on web page for details • Attend the tutorial/workshop group assigned on the web page • Make sure you know your assigned marker’s email! CP2022 - Multimedia Internet Communication

5. Outline summary 1 Introduction to communication 2 Computer communication 1 3 Computer communication 2 4 The Internet and WWW 5 Information structure and encoding 6 Mixed information types CP2022 - Multimedia Internet Communication

6. Outline summary 7 HTML and hypertext 8 PC and media exchange standards 9 Media communication standards 10 Business communication 11 Case study 1 - Intranet 12 Course summary (revision) lecture CP2022 - Multimedia Internet Communication

7. Principles of Communication • Communication is The transfer of information • The transfer needs A channel • Multimedia communication uses Multiple channels CP2022 - Multimedia Internet Communication

8. Channels • Examples • Sound travels through the air • Air is the medium used there are many channels • Light and radio waves are electromagnetic radiation • the medium is the “ether” • Different frequencies give different channels CP2022 - Multimedia Internet Communication

9. Choice of channel • Availability of channel • Availability of equipment • Ability to use channel • Ability to understand message • Economic considerations • Time problems CP2022 - Multimedia Internet Communication

10. Matching the channel to the information Example • Tennis match • Score only - use text or speech • More precise information - pictures can illustrate (e.g. racket shape, players, logos etc) • Full transmission of all available information would need video multiple channels if including many camera angles CP2022 - Multimedia Internet Communication

11. Media type and use • More complex information leads to bigger data objects • Communication of these requires bigger channels • i.e. more “capacity” or “bandwidth” CP2022 - Multimedia Internet Communication

12. Information • Data is the “raw” quantity • Information is data with “meaning” and “structure” • Examples DataInformation 2343256 Telephone number of a friend 29WS157QQ UK House number and postcode 2894251992 Product code of a compact disc CP2022 - Multimedia Internet Communication

13. Information structure • Data uses symbols Examples Name Symbols Binary numbers 0 1 Denary numbers 0 1 2 3 4 5 6 7 8 9 English alphabet a b c d e f g h i j k l m n o p q r s t u v w x y z • Symbols can be different but represent similar information E.g Greek, Cyrillic, Arabic or English alphabets all represent sounds CP2022 - Multimedia Internet Communication

14. In computer communication a message might be 234556671+25+23456673+100+23456688+10 This could be Order Part Number Quantity 234556671 25 23456673 100 23456688 10 Digital Information CP2022 - Multimedia Internet Communication

15. Communication of Information • Communication may involve errors • In digital communication where binary is used errors cause • 1 to become 0 and • 0 to become 1 • To detect or correct errors requires extra information (redundancy) CP2022 - Multimedia Internet Communication

16. Models of communication • Models are used to describe the process of communication • In ideal conditions CP2022 - Multimedia Internet Communication

17. Models • Information transfer may be slightly faulty CP2022 - Multimedia Internet Communication

18. Models • Noise affects information transfer CP2022 - Multimedia Internet Communication

19. Models • Data encoding is used to transfer information • Process model CP2022 - Multimedia Internet Communication

20. Models • Mostly multiple levels are used CP2022 - Multimedia Internet Communication

21. Models • Multimedia uses multiple encodings CP2022 - Multimedia Internet Communication

22. Example • Levels of encoding • An electronic mail message • High level • Language of the communication • Written symbols used • Computer representation of the symbols (ASCII) • Electronic binary signals (0 and 1) • Low level CP2022 - Multimedia Internet Communication

23. Principles of communication • Standards • Protocols • Error control, redundancy and accuracy • Channel • Context • Coding CP2022 - Multimedia Internet Communication

24. Standards • These can define a communication in some or all areas Example In an email message • The text will be in a standard language • Message format will be standard • Needs standard protocols for transfer CP2022 - Multimedia Internet Communication

25. Digital communication • All information used by computers is digitally encoded • In multimedia these are Video Audio Speech Sound and music Image Graphics Picture Text Free format Structured information CP2022 - Multimedia Internet Communication

26. Summary • Communication is about information • Information takes many forms • Multimedia communication is about encoding different forms of information on one or more channels with links between the different information types CP2022 - Multimedia Internet Communication