lectures on demand: delivering traditional lectures over the web

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Lectures On DEmand:delivering traditional

lectures over the Web.

Marco RonchettiDip. Ingegneria e Scienza

dell'InformazioneUniversità di Trento

Italy

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Lecture available on slidedshare

www.slideshare.com/ronchet

But beware!

Portability issue: some images missing because ppt was on a produced on a mac…

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Video streaming

"Streaming" refers to video that plays while you are connected to the internet.

You don't need to wait for the entire file to download to your computer before you can start watching.

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Bandwith

One hour of video encoded at 300 kbit/s (this is a typical broadband video for 2005 and it's usually encoded in a 320×240 pixels window size) will be:

(3,600 s · 300 kbit/s) / 8,388.608 = 128.7 MiB of storage

Modem users will not be able to view the higher bitrate streams (i.e., Cable/DSL or MPEG2).

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We can watch TV on the Internet

Well, sort of…

QuickTime e unﾪ ( )decompressore TIFF LZW

' .sono necessari per visualizzare quest immagine

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Coming from two perspectives…

Video on the Web Let's use it for teaching!

E-learning Let's use video!

Tech

nolog

y driv

en

Goal d

riven

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What a great idea!

…really?

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Teaching with videos?

Old idea (pre-web) Lectures on TV (1960…) Lectures on Videotapes (1980…)

COSTLY! Booooring… Unpractical Ineffective….

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Teaching with videos?

Don't do it! Unless there is something new…

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Let's not be so pessimistic…

What can we say from an

e-learning perspective?

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What do we use e-learning for?

Help traditional students e.g. provide learning material on-line

Support remote students Make some activity faster

e.g. semi-automatically grading tests Change the way we teach

Make it more collaborative Create a business

Get new markets (e.g. Athabasca) Sell content (e.g. SCORM lectures)

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Where can videos help?

Help traditional students e.g. provide learning material on-line

Support remote students Make some activity faster

e.g. semi-automatically grading tests Change the way we teach

Make it more collaborative Create a business - well, maybe…

Get new markets (e.g. Athabasca) Sell content (e.g. SCORM lectures)

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Traditional and remote students: how?

Modern pedagogy says:

Traditional lecturing is dead.

The lecture model is under attack by people proposing learner centered learning

E-learning is an opportunity for a change

However…

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Traditional and remote students: how?

… what is going on in your classroom?

At our place, we sometimes use a blended approach, much stuff is available through the net,

but the classroom is still there…

Can we make it any better, while the old paradigm still survives?

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Breaking the space-temporal unit

Can we free the student from spatial and temporal constraints?

Classical solutions: Paper-based learning material (FernUniversitaet, OpenUniversity) VHS cassettes (and TV or satellite broadcasting)

New solution: Webcast - but is it different?

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Teaching with videos?

COSTLY! Booooring… Unpractical Ineffective….

Well. Let's see…

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But we just said videos are no good…

… unless something new is there….

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Our experience

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We started in late 2003

Using e-presence:A software developed at KMDI at University of

Toronto, Canada, mostly designed for synchronous webcasting of seminars

Focus on remote interaction

Today (the only?) PD software of this kind in sourceforge

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e-presence today

ePresence Interactive Media is an Open Source Web Conferencing and Webcasting system that delivers video and synchronized presentation media over the internet using multiple streaming formats for multiple platforms. University of Toronto, Canada

http://sourceforge.net/project/showfiles.php?group_id=159579

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What was different?

COSTLY! -> lectures are there anyway… Booooring… -> lectures are not synthetic Unpractical Ineffective…. -> let's see…

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Cognitive interface

The main focus is on the projected slide, a clear voice is very important, the video carries additional information

like gestures, and can show the environment just enough

Navigation is possible

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Logical Architecture

Synchronous (webcast)

Asynchronous (On line, or download - podcast)

Asynchronous(CD - DVD)

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Our experience

Using e-presence we recorded in 1.5 years 9 university courses for a total of approx. 500 hours.

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In our case (2004 data)

Connections available to our students: 77% standard 56K analog modem 22% some kind of fast connection

7% ISDN (128:256 K)15% ADSL (256K) 1% no connection at all.

(but some of the students with slow connection have friends with ADSL)

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Student feedbackEnthusiastic. We were “forced” to

extend the experiment!

5%

63%

total 2nd exam (23 stud.)

1st exam(45 stud.)

students who…

4%6%…followed the course completely off-line

87%51%…used the system to review at least one lecture

75% anticipated using the system often or very often

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Advantages from student’s perspective

Better time management:ability to recover lectures lost due to forced absence

(illness, work or other time-frame incompatibility);ability to better organize their time, deciding not to be

present at some lecture (elective absence); Better understanding

review some critical point (cases of poor understanding of a section due to concentration drop, excessive speed in an explanation or intrinsic difficulty);ability to check the correctness of notes taken during a

lecture;

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Other advantages Miscellaneous

perception by the student of a better service provided by the university;support foreign (italian) students who might

have difficulties with the Italian (English) language;enrichment of the e-learning portfolio;possibility for the teacher to view himself;possibility to reuse lectures (across time, or

in different contexts!)

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We learned that: Synchronous webcasting is not important Alternative distribution channels are

importantDownloadCD/DVD

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Our requirements

the lectures should be easily browsed, with some form of indexing and a direct access to any time-location in the lecture;

lectures should be visible on all major platforms (Windows/Linux/Macintosh)

lectures should be available (in some form) also to students who do not have a large band Internet connection;

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Our requirements

impact on lectures should be minimal;

production costs should be minimal, so as to allow scaling the approach to most courses.Operations must be simple (low level skills!)Post-processing operations must be light (i.e.

almost automatic), and not require much work

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Our requirementsCognitive focus must be more

controllableIt must be also possible to use the

blackboard!Set-up must be lightweight!

agile and light setupeasy transportability

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Our requirementsWe tried to push our requirements in the

e-presence development pipeline

We ended up writing our own software:Lectures On Demand

(Not because of NIS…)

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LodeSupporto della didattica tradizionale

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LODE: the user interface

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Acquisition setup

QuickTime e unﾪ ( )decompressore TIFF LZW

' .sono necessari per visualizzare quest immagine

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Acquisition - User interface

QuickTime e unﾪ ( )decompressore TIFF Non compresso

' .sono necessari per visualizzare quest immagine

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System Architecture

OnStage WebServer

VideoStreamer

DVD

Browser

LODEacquisition

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Portability (End user requirements)

Windows: Internet Explorer or Mozilla Firefox Java and Javascript must be enabled QuickTime plug in

Mac OsX: Mozilla Firefox Java and Javascript must be enabled QuickTime plug in

Linux: No QuickTime plug in available! Partial support

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The system

1st version: Windows - Delphi. Problem: maintainability!

2nd version: Linux version (2003: acquisition - Ubuntu, postprocessing Fedora)

3rd version: moved to a Windows XP (2005) to have a more familiar environment (!). Acquisition and post processing can be done on the same machine.

4th version: client moved to Flash (!)

Available! But: not a product! Installation not simple!

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New Flash version

QuickTime e unﾪ ( )decompressore TIFF LZW

' .sono necessari per visualizzare quest immagine

http://latemar.science.unitn.it/SSSW07/Gangemi-OntologyDesign/content/start.html

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Lode - portabilitySupporto della didattica tradizionaleMac – Win - Linux

Player MP4(Video+audio,n

o slides)

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Lode - portability

Supporto della didattica tradizionaleSymbian based phones

(Nokia N70)

Audio + slides+zoom

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Is it really suitable for m-learning?

5 minute value: ability to use small fragments of time for learning Simplicity: limited display and input capabilities not practical

to transpose a power-point presentation on a PDA; Context dependent information:

location context; the system knows the location where the learner resides and adjusts to it;

temporal context; the system is aware of time dependent data; behavioral context; the system monitors the activities performed by

the learner and responds to them adjusting its behavior; interest specific context: the system modifies its behavior according

to the user’s preferences.

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Is it really suitable for m-learning?

Yes, at the airport…Maybe, we are assessing students…

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Extensions

Additional material attached to a point in the lecture…

Integration of (shared) annotation…Cut and sew to reflect TOPICS instead

of temporal organization…

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Use

We recorded international Summer Schools in Europe and

Asia Courses and events at University of Trento We gave the system to University of

Innsbruck, Austria (not in use yet)

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Assessing costs:

Equipment (easy)Running costs (this is what kills

projects!)

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Assessing costs: initial costs:

Software acquisition(almost) 0 Euro (QuickTime, Java, Javascript, Darwin Streaming

Server, open source components, our sw + one non-free component)

Hardware acquisition:SERVER 1000 EuroACQUISITION STATION 1400-2400 Euro

1 Laptop (Euro 800-1500)1 Digital Camera (Euro 400)1 Radio Microphone (Euro 200-500)

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Assessing costs: running costs setting up the system before lectures (10 min.) running the system during the lecture (2 hours) removing the system after lectures (5 minutes) starting the post-processing: 5 minutes. The post processing would

then go by itself for approx. 1 hours for producing a streams of 1 hour.

ending the post-processing (uploading the video on the web site, producing the master CD): 15 minutes.

35 minutes extra work for a 2 hours lecture

Network ?

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Today: many other similar systems

EyAVideolectures.netWebinars of various sorts…

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Some examples:

http://www.sciencelive.org/component/option,com_mediadb/task,play/idstr,CU-CSF-PC07-05_DarwinCorrespondence/vv,-2/Itemid,26Videolectures.net

http://sdu.ictp.it/eya/about/examples/roomD_2007.04.13_10.00-10.59/index.html http://videolectures.net/iswc07_pell_nlpsw/ http://epresence.kmdi.toronto.edu/Presentation/16

http://epresence.kmdi.toronto.edu/Presentation/193

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Browser independence…

QuickTime e unﾪ ( )decompressore TIFF LZW

' .sono necessari per visualizzare quest immagine

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Questions for you

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Why do you need the video ?

Presence feelingVideo carries useful information (e.g.

gesture)Video carries essential information (e.g.

blackboard!)

=> Video or not, operator or not

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Why do you need the slides ?

Slides carry essential informationSlides are only a help for the teacherYou need more than the slides…

(e.g. videos, live demos etc)

Capture screen (camtasia-like)?

Capture video signal (KMI - OU) ?

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How important is format ?

Browser independence? Intranet solutions General audience

Network independence? Various resolutions Download Other means (DVD…)

Device independence? Mobile learning

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How important is transportability ?

Higly optimized static settings?Light equipment?

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Do you need temporal markers ?

To facilitate navigation? I guess yes, but… How do you create them? (image

recognition?)

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Do you want to users to be able to give feedback/interaction ?

Lecture gradingGeneral annotationTemporally marked annotationReal time interaction (Synchronous

events)

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Can you interfere with the teacher?

Many speakers do not like to be recorded

They do not want to be disturbedThey do not want to adapt (ppt vs latex,

macros in ppt, blackboard?)

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When you'll have lots of stuff…

How will the users find their own way through? Semantic marking Access portal User evaluation/ranking Summaries Keywords Thematic catalogues

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Be clear!

Define your goalsDefine your costsDefine your process

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Can we do more?

Scenario:

Thousands of recorded lectures.

Can we dig in them to extract material for (less formal) learning?

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Needle - search results

QuickTime e unﾪ ( )decompressore TIFF Non compresso

' .sono necessari per visualizzare quest immagine

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Needle - architecture

ASR

Multimodal search!

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Needle - ASR

We used 2 ASR:

-A) a speaker independent research system, used for transcriptions of the Italian parliament

-B) a commercial (dictation) system

-A) gave 60% word accuracy on sample-B) gave 76,6% word accuracy (after speaker training, in simulated environment)

-Why so bad? Mike, but not only…

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Needle - Vocabulary

Research system vocabulary contained 62,879 words

Manual transcription contained 702 terms - 57 not present in vocabulary36 were technical termsRest was english or spanish words, company names, other minor stuff (re-…, diminutives).

Language model is important!We took Java books (11,443 terms before stemming - added to the vocabulary and decreased the unrecognized words from 8% to 3%)

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ASR - is it good?

For information retrieval - yes.

Rare false positive on interesting domain!

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Questions

Is it useful?

Is it effective?

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Scenario100% accurate transcription (manually corrected)

Goal: extract some info from a 2 hour lecture in half of the time…

Assess whether the tool could reduce the learning time and help students in their learning task: we do not aim at claiming or proving that a course delivery mode is better than the other.

Comparing delivery modes (e.g. distance learning with traditional classroom-based instruction) (Sener 2005) for the purpose of establishing the superiority of one delivery mode over another is specious, irrelevant and counterproductive because there is not an uniformity of practice.

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Experiment68 students, after 20 hours of a 50 hour Java course.

Group A: LODE

Group B: NEEDLE

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ExperimentPre-Test: 5 questions, 5 minutes

LODE group: 70 minutes for the lecture, plus24 minutes for the post-test (8 questions): total 94 minutes to

accomplish the task

NEEDLE group: 48 minutes total for responding to the same 8 questions (50% of the time)

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Pre-test results

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Test results

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AnalysisIn the subset of questions, which require students to have a

complete understanding of a part of the lecture both groups performed in the same way.

In answering those questions that also required some reasoning about concepts, group LODE – who had listened to the entire lecture – performed better.

In the questions where the students where asked to provide the right definition for a concept group NEEDLE performed better.

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Further investigationsMultivariate regression:- no significant results

Clustering techniques- Indication that some feature seem to be present -

investigation is still on its way

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Conclusion NEEDLE tool is more geared towards information

finding than towards actual learning.

A similar pattern could be reasonably expected in a similar experiment performed by reading some assigned material versus searching quick answer with Google.

However, our finding seems to show that Needle works very well as a tool for extracting information from a video source.