1. MADUF
Interactivity
WP 4.3, WP 4.4, WP 4.6
UGent-MMLab
VUB-ETRO
UGent-IBCN
UGent-WiCa
Afsluitevent 20/03/2008

2. 2/12
Overview
 What is interaction?
 Interactivity platforms
 Synchronization media streams – applications
 Synchronization architecture
 Object-based interactivity

3. 3/12
WP 4.6 What is Interaction?
 Not only switching channels and digitext
 Interaction
 Local
 Quality adaptation
 Subtitle selection, audio channel selection
 Remote
 ESG
 Side information
 Voting, live quiz, VOD,…
 Has impact on device, server and communication
 Return channel needed (e.g. UMTS, SMS, Bluetooth)
 Extra information has to be sent through broadcast

4. 4/12
WP 4.6 Interactivity on mobile devices
Complexiteit
Functionaliteit

5. 5/12
WP 4.3 Synchronization for applications
 Problems:
 No existing specification/solution for mobile devices
 MHP and JAVA TV API focus on more advanced devices
 JSR 272 specification is not ready (current status: Proposed Final Draft 2)
 Java MIDP 2.0 does not support dynamic application management
 No open framework for synchronization
 Main Goal:
 Design of a synchronization framework
 Support for the MADUF architecture

6. 6/12
WP 4.3 Synchronization framework
 A client-server architecture
 A server component is added to the headend
 Extra middleware is installed on the clients
 The server component
 Provides synchronization by analyzing
 RTCP Sender Reports to calculate the time offset of the occurrence of an
event with respect to the A/V decoder clocks
 SDP files for clock rate parameters
 Steers the Application Management middleware (based on ESG)
 Steers the client applications by using an Event-Trigger mechanism
 Event: description of a specific action
 Trigger: the occurrence of an event
 Network Time Protocol (NTP) as time basis (≠ Normal Playing Time)

7. 7/12
WP 4.3 Synchronization framework
 Standard DVB-H/IP Datacast headend as starting point
MPEG2 TS
H264/AAC RTP /UDP/ IP
SDI
IP
SDP
XML
IP
ESG
File

8. 8/12
WP 4.3 Synchronization framework
 The Interactivity Server integrated in the headend
RDP
IP
IP
SDP
ESG
IP

9. 9/12
WP 4.4 Object-based interactivity
 Requirements for standards:
 Clickable region specification
 Action specification
 Scene description
 Synchronization
 Requirements satisfied by:
 MPEG LASeR/SAF
 Designed for mobile use (low bandwidth)
 2 implementations tested (both with restrictions)
 GPAC
 Streamezzo

10. 10/12
WP 4.4 GPAC Demo
 Features offline video streams but supports realtime streaming
 Effectively only runs on PC
 PoC – 2 demo’s
 Mosaic
 Choose TV channel by click
 Return to mosaic
 Casino
 Information bar with scrolling information
 Clickable information bar shows clickable region
 Clickable region activates popup on information bar

11. 11/14
WP 4.4 GPAC Demo

12. 12/14
WP 4.4: Streamezzo Demo
 Features offline video streams but supports realtime streaming
 Runs on PC, as well as on PDA and smartphone
 Contains 3 phases
 Mosaic
 Choose channel by click
 Channel
 Adapt sound volume and video quality
 Switch channels
 Return to mosaic
 Game
 Question with possibility to send sms

13. 13/14
WP 4.4: Streamezzo Demo

14. 14/14
Conclusion
 Many approaches are possible to implement interactivity
 Applications and multimedia can be synchronized without
major changes in the DVB-H headend
 MPEG/LASeR is promising, implementation still
problematic