CAV 1 Aula 1 2007 English - Instituto de...

Audiovisual Communications, Fernando Pereira

AUDIOVISUAL

COMMUNICATIONS

AUDIOVISUAL AUDIOVISUAL

COMMUNICATIONSCOMMUNICATIONS

Fernando Pereira


Professor-Students Relationship …ProfessorProfessor--Students Relationship Students Relationship ……


MEEC: Web Page and Mailing ListMEEC: Web Page and Mailing ListMEEC: Web Page and Mailing List

http://http://www.img.lx.it.pt/~fp/cav/com.htmwww.img.lx.it.pt/~fp/cav/com.htm

To subscribe the CAV mailing list send a message

to [email protected]

Mailing list address:

[email protected]


MERC: Web Page and Mailing ListMERC: Web Page and Mailing ListMERC: Web Page and Mailing List

http://http://www.img.lx.it.pt/~fp/cav/com.htmwww.img.lx.it.pt/~fp/cav/com.htm

To subscribe the CAV mailing list send a message

to [email protected]

Mailing list address:

[email protected]


MEEC: Lectures ScheduleMEEC: Lectures ScheduleMEEC: Lectures Schedule

THEORETICAL LECTURES

� 2 lectures of 90 minutes per week - Monday at 17.00 (EA1) and Wednesday at 15.30 h (EA1)

PRACTICAL/LABORATORY LECTURES

� 1 lecture of 2 h per week – Monday at 9.30 h or 11.30 h or Wednesday at 11 h at Laboratório de Telecomunicações 4 (4º floor of Torre Norte)


MERC: Lectures ScheduleMERC: Lectures ScheduleMERC: Lectures Schedule

THEORETICAL LECTURES

� 2 lectures of 90 minutes per week – Tuesday at 14.30 (A5) and Thursday at 14.30h (A5)

PRACTICAL/LABORATORY LECTURES

� 1 lecture of 2 h per week – Tuesday at 16 h in Lab. 1.26 or in ou Room 0.23


Some Theoretical Lectures in EnglishSome Theoretical Lectures in EnglishSome Theoretical Lectures in English

The decision to lecture some theoretical lectures in English has the target to improve the skills of MEEC students and thus their market value considering that:

� English skills are nowadays fundamental for engineers whatever the country they work;

� Even at national level, engineers need a good knowledge of English in terms of reading, listening and speaking;

� The free circulation of people, notably engineers, in the European Union led to the situation that a growing number of MEEC graduates work out of Portugal;

� IST should differentiate itself from other schools by the increased skills it provides to its students and the usage of innovative teaching solutions;

� IST receives many foreign students who cannot follow the lectures in Portuguese;

� IST is part of a CLUSTER which integrates many European universities;

� In general, students have nowadays a good knowledge of written and spoken English.


CAV Studying MaterialCAV Studying MaterialCAV Studying Material

Studying material made available consists in:

� Slide from theoretical lectures (available at CAV Web Page)

� Supporting texts for each chapter

� Available at AEIST Secção de Folhas

� Available at the CAV Web Page

� Collection of exercises with the corresponding solutions (available at CAV Web Page)

� Laboratory guides (available at CAV Web Page)

� Exams from previous years with solutions (available at CAV Web Page)


Evaluation MethodEvaluation MethodEvaluation Method

The CAV evaluation method includes three components, notably:

1. FINAL EXAMINATION held after the end of the lecturing period (with weight 65%);

2. SCIENTIFIC DIVULGATION PAPER about a selected topic, to provide on a date to be set (weight 25%);

3. LABORATORY PARTICIPATION to be evaluated through the filling of a form during the laboratory session (weight 10%).

The final mark is computed by:

Final Mark=int[ 0.65Final Mark=int[ 0.65××××××××Examination_MarkExamination_Mark + 0.25+ 0.25××××××××Paper_MarkPaper_Mark+0.1+0.1××××××××(Sum_Lab_Marks(Sum_Lab_Marks××××××××20/2/Num_Labs)]20/2/Num_Labs)]

where Sum_Lab_Marks is the sum of the lab marks and Num_Labs is the number of lab sessions.


Evaluation Method: Some Rules …Evaluation Method: Some Rules Evaluation Method: Some Rules ……

� EXAMINATION:

� The minimum mark for the examination is 9.5.

� LABORATORY PARTICIPATION:

� The participation in the lab has no minimum mark.

� The mark for each filled lab form is an integer number bewteen o and 2.

� The students not present at a lab session will get a ‘0’ mark for that session.

� DIVULGATION PAPER:

� The minimum mark for the divulgation paper is 9.5.

� The divulgation paper should preferably be written in groups of 3 students.

� The divulgation paper mark is individual even if the paper is a group work.

� The evaluation of the divulgation paper may include a presentation and/or discusson if the

supervising professor finds it necessary.

� FINAL MARK:

� The students with a computed final mark higher than 17 will have to make an oral

examination to confirm the mark; not making this examination, if requested, implies

getting a mark of 17.


About the Divulgation PaperAbout the Divulgation PaperAbout the Divulgation Paper

� The divulgation paper consists in a tutorial and pedagogical text about a relevant topic related to audiovisual communications.

� This paper has to target to stimulate in the students the contact with bibliographical research and also with relevant companies.

� The paper will be produced in two versions:

1.1. Paper version Paper version which shall not have more than 8 PAGES8 PAGES using the

template made available.

2.2. HTML versionHTML version with a similar content of the paper version but exploiting

HTML capabilities typical of Web content, e.g. including video and audio

material and interactivity.

For the year of 2006/2007, the deadline for the divulgation papeFor the year of 2006/2007, the deadline for the divulgation paper is r is

25 May 2007.25 May 2007.


Example Topics for the Divulgation PaperExample Topics for the Divulgation PaperExample Topics for the Divulgation Paper

� Acquisition and visualization of images

� Videotelephony and videoconference

� Digital Video Broadcasting

� Digital Video Disc

� TV Anytime

� Interactive television

� Internet video

� Television in Portugal

� Video on demand

� Automatic music retrieval

� GSM speech coding

� Audio coding

� MP3

� Multimedia content protection

� MP3 versus AAC

� iPod

� iPhone

� Mobile multimedia

� IPTV

� Digital terrestrial television

� Cable TV in Portugal: comparing services

� Digital TV: the competing alternatives

� Video surveillance

� Satellite video

� Video coding: the format war

� Audio coding: the format war

� High definition video

� Digital TV in Portugal: comparing services

� Mobile video in Portugal: comparing services


MEEC: Assigning the Divulgation Paper TopicsMEEC: Assigning the Divulgation Paper TopicsMEEC: Assigning the Divulgation Paper Topics

Starting this Wednesday, at the practical

lecture at 11 am in LT4 !


MERC: Assigning the Divulgation Paper TopicsMERC: Assigning the Divulgation Paper TopicsMERC: Assigning the Divulgation Paper Topics

Starting this Tuesday, at the

practical lecture at 4 pm in Room 0.23 !


MEEC: Lab Registration MEEC: Lab Registration MEEC: Lab Registration

Send message to [email protected] choosing

between Monday (9.30 or 11.30 am) and

Wednesday (11 am).

Assignment by order of arrival !


MERC: Lab Registration MERC: Lab Registration MERC: Lab Registration

Send message to [email protected] with the

names for each group.


Program: a Program: a Quick ReviewQuick Review


ProgramProgramProgram

� 1. Introduction

� 2. Analogue Audiovisual Communication Systems

2.1 Black and white analogue TV

2.2 Colour analogue TV

� 3. Digital Audiovisual Communication Systems

3.1 Facsimile

3.2 Digital imaging

3.3 Videotelephony and videoconference

3.4 Digital video storage

3.5 Digital television

3.6 Advanced audiovisual communication systems

� 4. Trends on Audiovisual Services


Program: an Evolutive PerspectiveProgram:Program: an Evolutive Perspectivean Evolutive Perspective


Audiovisual CommunicationsAudiovisual CommunicationsAudiovisual Communications

Transference of image, audio and video Transference of image, audio and video

information through space, time, or space information through space, time, or space

and time simultaneously. and time simultaneously.


The Importance of the User …The Importance of the User The Importance of the User ……


We All Communicate …We All Communicate We All Communicate ……


Sensations, Perceptions and Emotions …Sensations, Perceptions and Emotions Sensations, Perceptions and Emotions ……


Communicating Since a Long Time Ago …Communicating Since a Long Time Ago Communicating Since a Long Time Ago ……


And After Telecommunicating …And After Telecommunicating And After Telecommunicating ……


What do the Users Want ?What do the Users Want ?What do the Users Want ?

� Information

� Entertainment

� Communication

� Games

� Education

� Shopping

� …


How can Clients be Convinced ?How can Clients be Convinced ?How can Clients be Convinced ?

�Satisfaction of personal needs

�Added value, new capabilities

�Interoperability

�Quality and robustness

�Content variety

�(Low) cost of equipment and usage

�Easy usage


Satisfaction: Quality versus ServiceSatisfaction: Quality versus ServiceSatisfaction: Quality versus Service

The minimum required quality of service depends on the service in question:

� Facsimile

� Digital image (bi-level, grey or colour)

� Analogue TV

� Videotelephony

� Videoconference

� Digital television

� High definition digital television


Personal Communications versus BroadcastingPersonal Communications versus BroadcastingPersonal Communications versus Broadcasting

� Real-time versus download

� Point-to-point versus point-multipoint

� Unidirectional versus bidirectional


Passive versus Interactive ServicesPassive versus Interactive ServicesPassive versus Interactive Services

Critical delay

requirements for

interactive services !


Analogue Communications World …Analogue Communications World Analogue Communications World ……


Digital Communications World …Digital Communications World Digital Communications World ……

Digital representation bitrate

Claude ElwoodClaude Elwood SHANNON, SHANNON, 19161916--20012001

Harry NYQUISTHarry NYQUIST, , 18891889-- 19761976

Channel capacity


Bit Jumping …Bit Jumping Bit Jumping ……


Why is there a Need for Coding ?Why is there a Need for CodingWhy is there a Need for Coding ??

An image is created and consumed as a set of M××××Nluminance and chrominance samples with a certain number of bits per sample (L)

The total number of bits

- and thus bandwidth and memory – needed to digitally represent an image is HUGE !!!

Without coding ...


The Coding Miracle …The Coding Miracle The Coding Miracle ……

Codificador

Descodificador


Digital TV: Only an ExampleDigital TV: Only an ExampleDigital TV: Only an Example

� ITU-R 601 standard: 25 images/s with 720 ×××× 576 luminance

samples and 360 ×××× 576 samples for each chrominance, at 8 bit/sample

[(720 ×××× 576) + 2 ×××× (360 ×××× 576)] ×××× 8 ×××× 25 = 166 Mbit/s

� Practical bitrate: 2 Mbit/s

=> Required Compression Factor: 166/2 ≈≈≈≈ 80

The difference between coding or not implies the existence or not of many largely used services.


The Secret of the Miracle …The Secret of the Miracle The Secret of the Miracle ……

�� REDUNDANCY REDUNDANCY – related to the similarities, correlations and predictability between the samples of images, video or audio.

�� IRRELEVANCYIRRELEVANCY – related to the information inperceptible for the human visual or auditory systems.


The Consequences of the Miracle (1) …The Consequences of the Miracle (1) The Consequences of the Miracle (1) ……


The Consequences of the Miracle (2) …The Consequences of the Miracle (2) The Consequences of the Miracle (2) ……


The Impact of Interoperability …The Impact of Interoperability The Impact of Interoperability ……


Copying: The Snowball EffectCopying: The Snowball EffectCopying: The Snowball Effect


Business Model: The Key to Success ...Business Model: The Key to Success ...Business Model: The Key to Success ...

A business model is the method of doing business by which a product/service can sustain itself - that is, generate revenue.

Some business models are quite simple. Other models can be more complex such as free television. The broadcaster is part of a complex network of

distributors, content creators, advertisers, and listeners or viewers. Who makes money and how much is not always clear at the outset.

� Digital representations and networks give rise to new kinds of business models, since acquiring, transmitting, and storing information (now just bits) became much easier.

� But it is also likely to reinvent ‘old’ models such as auctions. New and interesting variations of old models should be expected in the future.


New Systems and … New Business Models …New Systems and New Systems and …… New Business Models New Business Models ……

iPod may play the following audio formats: MP3, WAV, AAC, Protected AACProtected AAC, AIFF and Apple Lossless).


The Revolution …The Revolution The Revolution ……


Too Much is Too Much …Too Much is Too Much Too Much is Too Much ……


Filtering TV …Filtering TV Filtering TV ……


Looking for

Napoleon ?

Looking for Looking for

Napoleon ?Napoleon ?


Speaking a new ‘Visual Language’ …Speaking a new Speaking a new ‘‘Visual LanguageVisual Language’’ ……


Speaking a new ‘Audio Language’ …Speaking a new Speaking a new ‘‘Audio LanguageAudio Language’’ ……


Simple but Powerful ...Simple but Powerful ...Simple but Powerful ...


The Semantic Jump ...The Semantic Jump ...The Semantic Jump ...

“I want to see the goals of a

Benfica-Sporting ...”

Football goal low-level definition =

� Fast horizontal movement +

� Cheering from the crowd +

� Slow motion repetition +

� Fixed shot of the centre of the

field


Multimedia in PortugalMultimedia in PortugalMultimedia in Portugal

� It is today much easier than before to create and sell audiovisual communication related products (mainly software based).

� Internet helps the success of small, innovative companies created without much investment.

� The competition between companies may stimulate also the operators to embrace more innovative challenges.

� Users are increasingly open to new services.

� International contact is changing old habits and prejudices …

Multimedia technology, in general, is an interesting field for Multimedia technology, in general, is an interesting field for Portuguese young engineers with initiative to launch their own Portuguese young engineers with initiative to launch their own

companies !companies !


About Forecasting …About Forecasting About Forecasting ……

This flat TV ad appeared in 1945 in a English newspaper !

Advices about forecasting:

� You may try o forecast ‘WHAT’ …

� But never try to forecast ‘WHEN’ …

CAV 1 Aula 1 2007 English - Instituto de...

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