maduf05 interactivity tom paridaens
TRANSCRIPT
MADUF
Interactivity
WP 4.3, WP 4.4, WP 4.6
Afsluitevent 20/03/2008
UGent-MMLab VUB-ETRO UGent-IBCN UGent-WiCa
Overview
What is interaction?
Interactivity platforms
Synchronization media streams – applications
Synchronization architecture
Object-based interactivity
2/12
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
3/12
WP 4.6 Interactivity on mobile devices 4/12
Complexiteit
Functionaliteit
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
5/12
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)
6/12
WP 4.3 Synchronization framework 7/12
ESG
File
IP
SDP
XML
SDI H264/AAC RTP /UDP/ IP
IP
MPEG2 TS
Standard DVB-H/IP Datacast headend as starting point
WP 4.3 Synchronization framework 8/12
SDP ESG
IP
IP
IP RDP
The Interactivity Server integrated in the headend
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
9/12
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
10/12
WP 4.4 GPAC Demo 11/14
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
12/14
WP 4.4: Streamezzo Demo 13/14
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
14/14