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Utilization of Digital Television Technologies for E-learning
LADL Conference
1st LOGOS Open Workshop
20 September 2007
Budapest
Dr. Sándor Bozóki, András Gnandt, György SogrikAntenna Hungária Corp.
LADL 2007 Utilization of Digital Television Technologies for E-learning
E-learning infrastructure based on digital television networks planned in the framework of the LOGOS project
LADL 2007 Utilization of Digital Television Technologies for E-learning
DVB Data Broadcast Configuration- enables delivery of e-learning material as files and packages
Data broadcast
server
Content server
User management
and billing
Data broadcast
management
ISDN/Leased line/
Internet
Content providers
IP/DVB gateway
Video/audio signals
QPSK modulator
QAM/QPSKmodulator
OFDM modulator
MUX
Data broadcast provider Multiplex provider
Data broadcast
server
Content server
User management
and billing
Data broadcast
management
ISDN/Leased line/
Internet
Content providers
IP/DVB gateway
Video/audio signals
QPSK modulator
QAM/QPSKmodulator
OFDM modulator
MUX
Data broadcast provider Multiplex provider
LADL 2007 Utilization of Digital Television Technologies for E-learning
MHP based interactive television• MHP is an open standard API, standards for
interactive television.• MHP works across all DVB transmission
technologies (DVB-S, DVB-T, DVB-C, IPTV).• MHP has a core based around a Java virtual
machine – DVB-J.• The innovation will result in MHP
applications which run as fast as native ones.
• MHP-based iTV technology enables e-learning applications accesible for all digital TV subscribers
LADL 2007 Utilization of Digital Television Technologies for E-learning
MHP API
• Resources are provided to MHP transparently• Portability: no direct addressing of resources,
System software provides an abstract view• Application Manager manages the lifecycle of
applications• API is the interface between applications and
System software
LADL 2007 Utilization of Digital Television Technologies for E-learning
MHP versions• MHP 1.0: Broadcast applications; Data via IP;
Satellite, Cable and Terrestrial support (commercially introduced)
• MHP 1.1: Applications via IP; Smartcard support; VOD support; DVB-HTML support (commercially introduced e.g. in Austria)
• MHP 1.2: DVB-IPTV profile; non-DVB IPTV profile (commercially not available yet)
• The latest versions allow for more sophisticated e-learning applications
LADL 2007 Utilization of Digital Television Technologies for E-learning
MHP profiles• Enhanced Broadcast Profile
– local interactivity, using remote control to interact with broadcast applications
– No return channel• Interactive Broadcast Profile
– IP over the return channel – TCP, UDP– DNS forward resolving protocols
• Internet Access profile– HTTP 1.0 with persistent connection support and not using Keep-Alive
when talking with proxies that doesn’t understand Connection– HTTPS
• IPTV Profile– RTSP– IP Service discovery (checks the signalling of services, no request to do
this more frequently than once per day)• The Internet access through television enables web-like e-learning
experience (but, of course, the processing and presentation capabilities are still lower than in case of PC’s)
LADL 2007 Utilization of Digital Television Technologies for E-learning
MHP profiles considered for e-learning
Enhanced Broadcast Profile Interactive Profile
Standalone learning Available, however only according to the broadcast schedule
Course limitations: * Mainly movie* Some text and pictures, at the same
time with the broadcast* Self-checking (test with Java)Records cannot be created about the
students’ test resultsSelf-educated learning
Available, however only according to the broadcast schedule
Course limitations: * Mainly movie* Some text and pictures, at the same
time with the broadcast* Self-checking with interactive testRecords can be created about the
students based on their test results (can help enhancing the course)
Self-educated learning
Collaborative learning (Instructor-led, facilitated, etc.)
Not available with pure MHP, because there is no communication among the students, nor with the facilitator.
Not available with pure MHP, because there is no communication among the students. Communication with the facilitator is possible through the return channel.
LADL 2007 Utilization of Digital Television Technologies for E-learning
MHP in broadcasting services• Typical applications:
– EPG– Information services (superteletext, running
banners)– Applications synchronized to the TV programs,
like voting, games, (questioning tests for LOGOS) etc.
– Electronic commerce and secure transactions• The methodology of the development and the
basic components of the above applications can be reused for iTV-based e-learning applications
LADL 2007 Utilization of Digital Television Technologies for E-learning
MHP based interactive television head-end systemwhich can serve the delivery of e-learning applications
LADL 2007 Utilization of Digital Television Technologies for E-learning
MHP content formats essential for e-learning
• Picture formats:– JPEG– GIF– PNG– MPEG-2 I-frame
• Text formats:– Monomedia text with UTF-8 character
encoding– DVB-HTML - optional
LADL 2007 Utilization of Digital Television Technologies for E-learning
MHP capabilities for e-learning
• Dynamic HTML pages using scripts and return channel
• Interactivity with defining actions for the remote control
• Sending back information via return channel
LADL 2007 Utilization of Digital Television Technologies for E-learning
Return channel technologies
• PSTN/ISDN, ADSL, GSM, GPRS – most common return channels for DVB services.
• DVB-RCT (Return Channel Terrestrial) – due to lack of frequency, it is not available on the market.
• DVB-RCS (Return Channel Satellite) – terminals capable of two-way satellite communication are still rather expensive.
LADL 2007 Utilization of Digital Television Technologies for E-learning
IPTV infrastructure for e-learning
LADL 2007 Utilization of Digital Television Technologies for E-learning
Set-top-box capabilities
System
Content formats and services supported by the set-top-boxes and handsets on the market
Video Audio Interactive application Supported services(AV decoding, presentation,
VOD, PVR storage)
DVB-T MPEG-2/H.264 MPEG-1 Layer 2/AC-3
MHP AV decoding, NVOD (Near Video On Demand), PPV, EPG, STXT (SuperTeleteXT), voting, chat, shopping, banking
DVB-S MPEG-2/H.264 MPEG-1 Layer 2/AC-3
MHP
DVB-C MPEG-2/H.264 MPEG-1 Layer 2/AC-3
MHP
DVB-H H.264 AAC/AAC+/eAAC HTML (HyperText Markup Language)
AV decoding, PPV (Pay Per View), NVOD
IPTV MPEG-2/H.264/WMT9
MPEG-1 Layer-2/MPEG-1 Layer-3 (MP3)/AC-3
ANT Fresco(sometimes Espial, Opera
and Internet Explorer 6) offering HTML 4 and JavaScript.
A/V decoding, NVOD, PPV, EPG, TSTV (Time Shifted Television), STXT, voting, chat, shopping, banking, VOD
LADL 2007 Utilization of Digital Television Technologies for E-learning
Conclusions• We have designed and integrated a DTV content
delivery platform in the framework of the LOGOS project.
• The limitations of DTV comparable to PC must be taken into account when developing e-learning applications.
• Content distribution via broadcast to many users is more cost-effective than via telecommunication channels.
• Content delivery platform should be assessed with real t-learning content during the tests planned for the next phase of the LOGOS project.
LADL 2007 Utilization of Digital Television Technologies for E-learning
Thank you for your kind attention!
András GnandtAntenna Hungaria Co.
http://[email protected]