© agency.com ltd 2000 a technical view of itv service creation sten lawætz presentation from...
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© AGENCY.COM LTD 2000
A technical view of iTV A technical view of iTV service creationservice creation
Sten LawSten Lawætzætz
Presentation from October 2000Presentation from October 2000
© AGENCY.COM LTD 2000
Presentation overviewPresentation overview 1. Broadcast technology1. Broadcast technology
Signal encoding and transmissionSignal encoding and transmission
2. Set-top box technology2. Set-top box technology Hardware, middleware, applicationsHardware, middleware, applications
3. Service application technology3. Service application technology Programming languages, programming Programming languages, programming
modelsmodels Service developmentService development workflowworkflow
4. Challenges4. Challenges
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A warning:A warning: Terminology is similar to traditional Terminology is similar to traditional
networking technologynetworking technology packets, streams, applicationspackets, streams, applications
...but 80% is slightly different...but 80% is slightly different TLAs abound (and mean different things)TLAs abound (and mean different things)
SMS, BAT, PAT, PID, TID, QAM, MUX ...SMS, BAT, PAT, PID, TID, QAM, MUX ...
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An iTV service - the big pictureAn iTV service - the big picture
HostConnection
DVB
equpiment
ApplicationServer
STB
VideoAudio
etc.Transmission
Database
Modempool
Flow Server
Encryption
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1. Broadcast technology1. Broadcast technology Video/audio compression standard Video/audio compression standard
algorithmsalgorithms
Transport layer specification (MPEG2 TS)Transport layer specification (MPEG2 TS)
Transmission meta-data (PSI/SI)Transmission meta-data (PSI/SI)
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Video/audio compressionVideo/audio compression Lossy compression, redundancy eliminationLossy compression, redundancy elimination
Time-difference coding (frame-based)Time-difference coding (frame-based)
VideoVideo DCT (discrete cosine transform)DCT (discrete cosine transform) I/P/B framesI/P/B frames macro-blocksmacro-blocks
AudioAudio MPEG1 layer 3 psycho-acoustical codingMPEG1 layer 3 psycho-acoustical coding 'mp3' format'mp3' format
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Transport streamsTransport streams TS roughly = 1 analog TV channelTS roughly = 1 analog TV channel
Formatted as MPEG2 packets (188 bytes)Formatted as MPEG2 packets (188 bytes)
Elementary streams (PES - packetized ES)Elementary streams (PES - packetized ES) VideoVideo AudioAudio TeletextTeletext Data...Data...
Multiplexed into the transport streamMultiplexed into the transport stream Merged on packet-level to fill up Merged on packet-level to fill up
bandwidthbandwidth
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Transport stream exampleTransport stream example Elementary streams merged with each otherElementary streams merged with each other
Audio component
Teletext component
Data / Application component
Video component
Stream
System Information
SI Stream
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Modulation techniquesModulation techniques QPSK - quarternary phase-shift keying QPSK - quarternary phase-shift keying
(sattelite)(sattelite)
QAM - quadrature amplitude modulation QAM - quadrature amplitude modulation (cable)(cable)
COFDM - coded ortogonal frequency division COFDM - coded ortogonal frequency division multiplexing (terrestrial)multiplexing (terrestrial)
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Transport stream meta-data Transport stream meta-data (MPEG2)(MPEG2) Similar to a directory (FAT for DOS-Similar to a directory (FAT for DOS-
dinosaurs)dinosaurs)
SI (service information)SI (service information)
PSI (program specific information)PSI (program specific information)
Tables of tuplesTables of tuples NIT, PMT, PAT, BAT, TDT, SDT, etc.NIT, PMT, PAT, BAT, TDT, SDT, etc.
Conditional access informationConditional access information
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Head-end hardwareHead-end hardware Video/audio sourcesVideo/audio sources
encoders, video servers, audio serversencoders, video servers, audio servers
MultiplexingMultiplexing service filtering, re-multiplexingservice filtering, re-multiplexing statistical multiplexingstatistical multiplexing
DistributionDistribution ATM, SDH, satellite relayATM, SDH, satellite relay
Modulation and RF gearModulation and RF gear Modulators, up-converters / combiners / filtersModulators, up-converters / combiners / filters
Data injectionData injection SI/PSI injectionSI/PSI injection Application data injectionApplication data injection
object carouselsobject carousels
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Right, how does it look then?Right, how does it look then? Tele Danmark iTV serversTele Danmark iTV servers
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The transmission chain The transmission chain revisitedrevisited
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2. Set-top box technology2. Set-top box technology Set-top box architectureSet-top box architecture
Essentially audio/video decoder hardware Essentially audio/video decoder hardware w. overlay graphicsw. overlay graphics
RTOS (real-time operating system)RTOS (real-time operating system) Middleware with API and application Middleware with API and application
environmentenvironment
"The great thing about standards is that "The great thing about standards is that there are so many of them"there are so many of them"
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Set-top box hardware Set-top box hardware componentscomponents CPUCPU
StorageStorage RAMRAM EEPROMEEPROM Flash RAMFlash RAM HarddisksHarddisks
DevicesDevices Smart-card readersSmart-card readers Tuners/demodulators/demuxersTuners/demodulators/demuxers MPEG decoding chipsets w. On-Screen Display MPEG decoding chipsets w. On-Screen Display
(OSD)(OSD) Return path modems (PSTN, ISDN, Cable, MMDS)Return path modems (PSTN, ISDN, Cable, MMDS) External buses (par/ser/SCSI/ethernet)External buses (par/ser/SCSI/ethernet)
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Set-top box schematicallySet-top box schematically
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Example STB hardware profileExample STB hardware profile Tele Danmark Kabel TV 'Selector'Tele Danmark Kabel TV 'Selector'
Sagem series 3000 IRD HardwareSagem series 3000 IRD Hardware 2 MB RAM2 MB RAM 2 MB Flash RAM2 MB Flash RAM 8 KB EEPROM (bootstrap)8 KB EEPROM (bootstrap) single tuner/demodulator/demuxsingle tuner/demodulator/demux IBM MPEG-decoding chipsetIBM MPEG-decoding chipset
256 color OSD256 color OSD PowerPC CPUPowerPC CPU Dual smart-card readerDual smart-card reader PSTN modem (14400 baud)PSTN modem (14400 baud) RS-232 / Centronics portsRS-232 / Centronics ports
OpenTV EN1 middlewareOpenTV EN1 middleware
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STB software architectureSTB software architecture JavaTV layered architectureJavaTV layered architecture
Applies to most other middleware Applies to most other middleware architecturesarchitectures E.g.: Swap ‘JavaTV’ for ‘OpenTV’E.g.: Swap ‘JavaTV’ for ‘OpenTV’
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Middleware / Operating systemMiddleware / Operating system Currently deployed systemsCurrently deployed systems
OpenTV (OpenTV)OpenTV (OpenTV) PowerTV (PowerTV)PowerTV (PowerTV) DigiCypher II (Scientific Atlanta)DigiCypher II (Scientific Atlanta) JavaTV (Sun)JavaTV (Sun) MediHiway (Canal+ technologies)MediHiway (Canal+ technologies) Betanova (Beta-research, D-box)Betanova (Beta-research, D-box) Liberate (Liberate)Liberate (Liberate) WebTV (Microsoft)WebTV (Microsoft) MHEG (eg. Philips)MHEG (eg. Philips)
Linux/OS9/VxWorksLinux/OS9/VxWorks
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API models (as in MHP)API models (as in MHP) Declarative (high-level)Declarative (high-level)
MHEGMHEG
Procedural (low-level)Procedural (low-level) OpenTVOpenTV PowerTVPowerTV MediaHiwayMediaHiway JavaTVJavaTV
Mixed modelsMixed models Liberate (html, javascript w. extensions)Liberate (html, javascript w. extensions) WebTVWebTV
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Programming languagesProgramming languages Procedural languagesProcedural languages
C/C++ (OpenTV, Betanova, Digicypher II)C/C++ (OpenTV, Betanova, Digicypher II) Java (JavaTV)Java (JavaTV)
Scripting languagesScripting languages PanTalk (MediaHiway)PanTalk (MediaHiway) HTML / Javascript (Liberate, WebTV)HTML / Javascript (Liberate, WebTV)
Declarative languagesDeclarative languages MHEG-5MHEG-5
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Application capabilities Application capabilities (OpenTV)(OpenTV) General data processingGeneral data processing
OSD renderingOSD rendering shape controlshape control
MPEG decoder controlMPEG decoder control video/audio playbackvideo/audio playback MPEG chipset commandsMPEG chipset commands
Peripheral controlPeripheral control Return path (modem)Return path (modem)
CA system interactionCA system interaction Tuner/de-mux controlTuner/de-mux control
ZappingZapping SI accessSI access
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Example: OpenTV Example: OpenTV programming modelprogramming model Single-tasking, single threadingSingle-tasking, single threading
API basedAPI based Windows API, X WindowsWindows API, X Windows
Event driven programmingEvent driven programming Don't call us, we'll call youDon't call us, we'll call you
Display tree manipulationDisplay tree manipulation
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Example: OpenTV iTV Example: OpenTV iTV applicationsapplications OpenTV iTV service demonstrationOpenTV iTV service demonstration
PortalPortal EPGEPG GamesGames
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3. Service development3. Service development Not just an STB applicationNot just an STB application
The components for 'real' interactive The components for 'real' interactive services:services: STB application (consumer front-end)STB application (consumer front-end) Application server (business logic)Application server (business logic) Subscriber Management Systems (access Subscriber Management Systems (access
control)control) Content delivery systems (transmission Content delivery systems (transmission
equipment)equipment) Content management systems (Content Content management systems (Content
authoring)authoring)
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Service development processService development process a) Concept specification a) Concept specification
b) System architecture designb) System architecture design
c) Graphical UI designc) Graphical UI design
d) OpenTV application design/iplementationd) OpenTV application design/iplementation Coding, graphic resource creationCoding, graphic resource creation
e) Content provisioninge) Content provisioning Back-end data acquisition and packagingBack-end data acquisition and packaging
f) Application server business logicf) Application server business logic Legacy system integrationLegacy system integration
g) Integration workg) Integration work
h) Deployment, operation and maintenanceh) Deployment, operation and maintenance
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Development tools used at Development tools used at AGENCY.COM iTVAGENCY.COM iTV Resource editingResource editing
Graphics editor (e.g Photoshop)Graphics editor (e.g Photoshop) Video editors (e.g. Premiere)Video editors (e.g. Premiere)
Application developmentApplication development HTML editorsHTML editors C/C++ compilers (e.g. GNU, Sun)C/C++ compilers (e.g. GNU, Sun) XML editors and parsersXML editors and parsers Custom processing systems (e.g. LISP, Custom processing systems (e.g. LISP,
XSL)XSL)
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Back-end technologies usedBack-end technologies used Base server platformsBase server platforms
Sun / Solaris UNIX serversSun / Solaris UNIX servers Windows NT PC serversWindows NT PC servers
Application serversApplication servers Oracle application serverOracle application server Custom built systemsCustom built systems
Database serversDatabase servers Oracle RDBMS, SyBase, InformixOracle RDBMS, SyBase, Informix
Platform specific systemsPlatform specific systems Streaming servers, flow serversStreaming servers, flow servers
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4. Challenges4. Challenges Creating content for the TVCreating content for the TV
Three-tier vs. two-tier networkingThree-tier vs. two-tier networking
Multi-platform issuesMulti-platform issues
Future direction of the STBFuture direction of the STB
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Creating content for the TVCreating content for the TV Presentation limitationsPresentation limitations
Screen size (640 x 480 [720 x 568] interlaced)Screen size (640 x 480 [720 x 568] interlaced) Viewer distance > 3 metersViewer distance > 3 meters
Navigation principle limitationsNavigation principle limitations No pointing deviceNo pointing device No 'back'-buttonNo 'back'-button
Performance limitationsPerformance limitations Limited storageLimited storage Limited CPU powerLimited CPU power
Design limitationsDesign limitations Network operator imposed 'branding'Network operator imposed 'branding'
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The fundamental difference The fundamental difference between W3 and iTVbetween W3 and iTV The three-tier networking modelThe three-tier networking model
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The multi-platform issueThe multi-platform issue Potentially hundreds of different tech profilesPotentially hundreds of different tech profiles
Data delivery path, return pathData delivery path, return pathBandwidth issues, format issues Bandwidth issues, format issues
(DVB/ATSC)(DVB/ATSC) Middleware, APIs and VMsMiddleware, APIs and VMs
Programming model, performance, Programming model, performance, functionalityfunctionality
STB hardware capabilitiesSTB hardware capabilitiesTuners, harddisks, storageTuners, harddisks, storage
Application serversApplication serversSecond tier fixed frameworksSecond tier fixed frameworks
The multi-platform challenge:The multi-platform challenge: Single content source, multiple target Single content source, multiple target
platformsplatforms
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Future directions on STBsFuture directions on STBs TV is still king -> streaming media rulesTV is still king -> streaming media rules
The interactive bit is still an add-onThe interactive bit is still an add-on
Slow convergence on standards (eg. MHP)Slow convergence on standards (eg. MHP) Diversity of proprietary systemsDiversity of proprietary systems
Blurring of the STB conceptBlurring of the STB concept Games consoles, 'the home entertainment Games consoles, 'the home entertainment
center'center'
Consumer broadband technologyConsumer broadband technology xDSL, the end of cable TV?xDSL, the end of cable TV?
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The challenges to changeThe challenges to change STB deployment inertiaSTB deployment inertia
millions of STBs already out theremillions of STBs already out there software errors have large impact on software errors have large impact on
acceptanceacceptance
Three-tiered distributionThree-tiered distribution The network operator's roleThe network operator's role
Proprietary technology prevailsProprietary technology prevails
Extremely complex technologyExtremely complex technology compared to WWWcompared to WWW
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SummarySummary 1. Broadcast technology1. Broadcast technology
Signal encoding and transmissionSignal encoding and transmission
2. Set-top box technology2. Set-top box technology Hardware, middleware, applicationsHardware, middleware, applications
3. Service application technology3. Service application technology Programming languages, programming Programming languages, programming
modelsmodels Service developmentService development workflowworkflow
4. Challenges4. Challenges
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Questions?Questions?
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Efterbehandling af Célia Efterbehandling af Célia Quico’s specialeQuico’s speciale Hvad er godt?Hvad er godt?
Hvad mangler du?Hvad mangler du?
Hvad har du brug for at vi uddyber?Hvad har du brug for at vi uddyber?
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Opgave til næste ugeOpgave til næste uge Start på en matrix over Start på en matrix over
TDC SelectorTDC Selector ViasatViasat Canal DigitalCanal Digital (Digitalt jordbaseret tv)(Digitalt jordbaseret tv)
Væsentlige teknologiske træk/begrænsninger ved den Væsentlige teknologiske træk/begrænsninger ved den enkelte operatørs platformenkelte operatørs platform STB specifikationerSTB specifikationer Mulighed for skalering af video/multiple streams Mulighed for skalering af video/multiple streams
osv.osv.
Jeg sender en Excel skabelon ud i aftenJeg sender en Excel skabelon ud i aften