1. Timothy K. Shih
Selected Topics for e-
Learning Technologies
(Digital TV and MHP)

2. Digital TV technologies
• Outline
– Part1: Introduction to DTV
– Part2: DTV receivers
– Part3: MHP middleware
– Part4: Interactive TV

3. Introduction to DTV

4. Introduction to DTV
• Outline
– DTV overview
– Characteristic of DTV industry
– DTV standard overview

5. DTV overview
• What does DTV mean?
– Higher Picture Resolution
• High definition program
– Multicasting
• More programs at the same channel and bandwidth
– Better Picture Quality
• Less noise
– New Type of Broadcasting Service
• Interactions

6. DTV overview
• Digital receivers
– STB v.s. iDTV
– STB (Set-top box)
• standalone
• Two separate remote control
• Cheap products
– iDTV (Integrated DTV)
• Integrating STB to TV
• STB is a part of DTV
• Future trend

7. DTV overview
• Viewing Experience with DTV
– Basic Functions
• Channel Scanning
• Channel Organization
• Channel Change Banner
• Now/Next Information
• Parental Guidance
• PIP/POP
• Teletext, ClosedCaption

8. DTV overview
• Viewing Experience with DTV (cont’d)
– – Advanced Functions
• EPG (Electronic Program Guide)
• PVR (Personal Video Recording)
• SSU (System Software Update)
• PayTV(CA/CI)
• Interactive TV (MHP)
• Mobile TV

9. DTV overview
• DTV Basic Functions
– Channel Scanning
• Different settings for Satellite/Cable/Terrestrial DTV receivers
• Automatically/manually scan
– Channel Organization
• Channel list
• Channel edit
• Favorite list
• Sort, delete, hide, …
• Lock/unlock channels

10. DTV overview
• DTV Basic Functions
– Channel change banner
• Program name, description
• Date/time, duration
• HD/SD, Dolby, Aspect ratio,
• Parental rating, subtitling
– Now/Next information

11. DTV overview
• DTV Basic Functions
– Parental Guidance
• by program rating
• by channel
• by time
– PIP & POP
• Picture in picture
• Picture out picture
• One tuner v.s. twin tuners

12. DTV overview
• DTV Basic Functions
– Teletext (TT)
• The users can access text information on TV.
– Closed Caption (CC)
• The caption is separated with video frames.
• MPEG-II allows different caption streams.

13. DTV overview
• DTV Advanced Functions
– EPG (Electronic Program Guide)
• Displaying program information: name, start
time/duration, description.
• Present/Following (now/next) v.s. Scheduled (weekly)
EPG
• Display one dimensionally or two dimensionally

14. DTV overview
• DTV Advanced Functions
– PVR (Personal Video Recording)
• Recording
• Time-based, EPG-based
• One time, periodically
– Playback
• Normal, FF, FR, Repeat
– Time shifting
– Stream Editing
• DVB-SSU (System Software Update)
– Over-the-air software update

15. DTV overview
• DTV Advanced Functions
– PayTV
• The access to services inside TS is
• allowed only when subscription
– CA (Conditional Access)
• Smart card verification system
• Middleware porting is needed
• Different STB for different CA providers:
• Nagravision, Viaccess, Irdeto, etc.
• Cheap but not compatible

16. DTV overview
• DTV Advanced Functions
– CI (Common Interface)
• Common PCMCIA interface for different
• CA modules
• Same STB for different CA smart cards
• Expensive but compatible

17. DTV overview
• DTV Advanced Functions
– MHP (Multimedia Home Platform)
• A middleware
• More applications than audio/video
• Java-like applications

18. Characteristic of DTV
industry
• Characteristics of DTV Industry
– A lot of industries are involved.
• Major components of the DTV system
– Content/Service Provider
• TV program, Movie industry, Music industry, Game industry,
• information industry,etc.
• Digital studio, storage, broadcasting equipments.
– Transmission Channel
• Satellite, Cable, terrestrial, fixed/mobile network
• Communication equipments
– Terminal devices
• TV, Set-Top Box, PC/NB, cellular, PDA, vehicle device, etc.
• IC(tuner/decoder/display), Panel, Storage, software, OS, etc.

19. Characteristic of DTV
industry
• Huge difference among different DTV
markets
– 1. Different DTV standards
– 2. Different ecological dispersion
– 3. Different market demands

20. Characteristic of DTV
industry
• DTV Standards
– ATSC: USA, Canada, Mexico, South Korea
– DVB: Europe, Australia, New Zealand,
Taiwan, etc.
– ISDB: Japan
– DMB-TH: China (2006/8)

21. Characteristic of DTV
industry
• Ecological dispersion (Satellite、Cable、
Terrestrial)
– USA
• 85% users watching cable TV.
– Taiwan
• over 85% users watching cable TV
– India, Indonesia , middle of Asia:
• Satellite TV
– In Europe, Japan and China
• urban : Terrestrial TV
• Suburban : Satellite TV

22. Characteristic of DTV
industry
• DTV standards in the world wide

23. Characteristic of DTV
industry
• Market Demands
– Picture Quality
• HDTV markets
• SDTV markets
– TV Size
• Large size of TV
• TV smaller than 30”
– Functionality
• PayTV
– CA, CI
• interactive DTV
– (MHP, OpenCable, …)
• PVR
• Various customization
– Integration
• Integrated with other consumer products, like HDD, DVD.
• Popular in Japan, Korea.

24. DTV Standard Overview
• ATSC standard
– Video: MPEG-II MP@HL (main profile, high level)
– Audio: MPEG-I layer I,II, Dolby AC-3
– System layer: MPEG-ll TS + PSIP
– Modulation: 8-VSB (terrestrial), 16-VSB(cable)
– Interactive middleware: DASE(old) ACAP(new)
• Main Features
– HDTV
• ATSC system supports 18 formats with 6 HDTV, 9 EDTV, 3 SDTV.
– Dolby AC-3
• ATSC boasts “theater quality" audio because it uses the Dolby Digital AC3 format to provide
5.1-channel surround sound.
– Low transmission power
• VSB requires half transmission power compared with COFDM, so ATSC signal coverage is
larger than DVB-T with same power.
• Good for N. America where many places are rural with lower population density.

25. DTV Standard Overview
• DVB standard
– Video: MPEG-II MP@ML (main profile, main level)
– Audio: MPEG-I layer I, II
– System layer: MPEG-ll TS + SI
– Modulation: COFDM (DVB-T/H), QAM(DVB-C), QPSK(DVB-S)
– Channel Bandwidth: 6/7/8MHz (ATSC 6MHz with fixed 19.39bps)
– Interactive middleware: MHP (Multimedia Home Platform)
• Main Features (DVB-T)
– SFN (Single Frequency Network):
• Since it is better at handling multipath, same channel freq can be used for adjacent areas. The
spectrum allocation is efficient.
– Mobile Reception
• Due to Guard Band and the better multipath handling in COFDM, it is good for mobile
reception.
– Two-way communication support
• DVB has standardized return channels RCS/C/T to provide bidirectional communication
which is good for interactive DTV.

26. DTV Standard Overview
• ISDB standard
– Include ISDB-T, ISDB-C, ISDB-S
– Video: MPEG-II
– Audio: MPEG-II AAC (allows 5.1 audio output)
– System Layer: MPEG-ll TS + ARIB STD B-10
– Modulation: DPSK, QPSK, QAM, OFDM
– Channel Bandwidth: 6MHz (3.7 ~23.2Mbps )
• Main Features
– ISDB-S is 1.5 times more efficient than DVB-S. (ISDB-S could
transmit at 51 Mbps with a single transponder, while DVB-S allows
at about 34 Mbps)
– ISDB-T has the most flexibility and efficiency for mobile and
portable reception, compared with DVB-T and ATSC.

27. DTV Standard Overview
• Mobile TV standards
– DVB-H (digital video broadcasting-handheld )
• Derived from DVB-T with improvement on low power consumption, mobile
reception, IP data casting.
– T-DMB (digital multimedia broadcasting)
• Derived from DAB. Used by South Korea.
– MediaFLO (Media Forward Link Only)
• Qualcomm’s technology to broadcast data to portable devices.
• FLO means transmission path is one-way, from tower to device.
• Verizon Wireless (second-largest wireless network in the U.S.) and Cingular
(merged by AT&T Wireless and become the largest wireless carrier in the U.S. )
announced to deploy MediaFLO in US.
– DVB-SH (digital video broadcasting-Satellite handheld Feb. 2007)
• to deliver IP based media content and data to handheld terminals like mobile
phones and PDAs via satellite.

28. DTV Standard Overview
• Profile and level
DTV broadcasting applications
• DVB: MP@ML (main profile at main level).
• ATSC: MP@HL (main profile at high level).

29. DTV receivers

30. What does a DTV receiver
do?
• Receives digital TV programs from a cable, satellite
or terrestrial network
• Decodes transport streams
• Outputs signals to television
– More interactions can be done
– Ex. Running applications on STB

31. Block diagram of a typical
receiver
Tuner Front-end
Smart card /
CA Module
MPEG-2
decoder
CPU
Middleware
SDRAM
Flash memory
Graphics
processor
Descrambler
MPEG-2
demultiplexer

32. The Front End
• Receiver
– Converting analog signal to digital one.
– Including the tuner and the front end
• The tuner
– Receives frequency-specified signal
– Demodulates the signal
– Turns the analog signal into a digital bitstream
• The front-end
– Error correction
– Removing packetization in the stream
– Outputs an MPEG-2 transport stream

33. The Demultiplexer
• Decoding information in TS for STB
– Elements in the current channel
• Audio and video streams
• Broadcast data streams
• Service information
– Service information for the network
• Passing streams to corresponding components
– Service information and data streams to the CPU
– Audio and video to the MPEG decoder

34. The MPEG Decoder
• Decoding audio and video streams and displaying them on
the screen
• Supporting graphical overlays
– Cursor, graphics
– Some receivers support up to five graphics planes
• Background, video, two graphics planes, cursor
• Supporting scaling, clipping and repositioning video
– But this may be limited

35. The CPU
• Deal with other tasks in the system
– Decoding and handling service information
– Decoding broadcast data streams
– User interaction
– Running built-in or downloaded applications
• Often integrated with the MPEG-2 decoder and other components
• Typical CPUs
– STMicroelectronics 551x family
– NEC EMMA2
– ATI Xilleon
– Broadcom BCM3560

36. Conditional access (CA)
• Anti-piracy system for pay-TV
– Decrypts data from input streams
• Depending what was encrypted by the network operator
– Worked on specified devices
• integrating with the receiver
• Smart card or similar device
• Each STB usually has one CA system integrated
– This is enough for most pay-TV systems
– The box is tied with the subscription, so only used on one network
and one CA system

37. Conditional Access (CA)
• Some CA systems require special hardware support
• Some network operators are now using pure software CA systems
– May still use smart cards for authentication
• CA systems may do more than just encryption
– Pair a smart card to a single receiver
• Smart card can not be moved to other receivers
– Provide a way of uniquely identifying the receiver
• Smart card serial number
– Prevent STBs moving to other household
• Second STB
• Every household must have their own subscription

38. Conditional Access (CA)
• Integrated CA systems are unsuitable for some markets
• May use a pluggable CA module instead
– Entire decryption solution on a PCMCIA card
– Smart card plugs in to PCMCIA card
– Used on retail systems to allow use with any network
• This has several limitations
– More expensive (PCMCIA card)
– Few vertical markets will use pluggable CA modules
– Less secure, in the case of DVB-CI
• Not all CA systems will support pluggable modules

39. Return channel
• Communicating with the network operator or service operator
– Ordering pay-per-view services, home shopping, home banking
• May be used for general network access
– Web browsing, email, chat
• Many types in use
– PSTN modem (usually 56K)
– Cable modem and ADSL modem
– Exotic technologies such as GSM, DVB RCS (return channel via
satellite)
– Not every receiver will have a return channel
– The cost is relatively high.
– It’s not necessary for all services.

40. Middleware
• A common software platform for application development
– Usually in C or Java
– Basic features
• Graphics & video manipulation, return channel access, access to
service information, etc.
• Provided middleware platforms today
– OpenTV (OpenTV Core)
– NDS (NDS Core)
– Canal+ (MediaHighway)
– PowerTV (PowerTV)
– Microsoft (Microsoft TV)
– Nagravision-Kudelski (Tsunami)
• Open middleware platforms
– MHP, OCAP, ACAP, JavaTV, ARIB-B23

41. Integration
• Cost is a major factor in STB manufacture
– Lots of competition
– Typical cost is ~100 USD to the network operator for a standard STB
• Retail is more expensive
• Many components get integrated to save cost
– Tuner and front end
– Demultiplexer/MPEG decoder/CPU/graphics processor
• Most current STBs are one- or two-chip solutions
– Depends on features needed

42. Block diagram of a typical
receiver
Tuner
Smart card /
CA Module
MPEG-2
decoder
CPU
Middleware
SDRAM
Flash memory
Graphics
processor
Descrambler
MPEG-2
demultiplexer
Front-end
Standard STB with pay-TV
support (integrated)
BOM Cost: ~80 USD
Integrated into front-end
Integrated into CPU

43. Block diagram of a basic
receiver
μController
SDRAM
ROM
Free-to-Air ‘zapper’ box
BOM Cost: ~30-40 USD
MPEG-2
decoder
SDRAM
MPEG-2
demultiplexer
Tuner /
Front-end

44. MHP middleware

45. What Is MHP?
• An open standard for interactive digital television
• Defined by DVB
• Related open standards
– DVB, MPEG, JavaTV
• Providing interactive functionality to develop application

46. What Is MHP?
• MHP is:
– A platform definition
– A set of Java APIs
– A set of HTML document type definitions
– A set of compatibility tests
• It is also:
– Compatible with current DVB-based solutions
– Freely available (specification available on the web)
• MHP has been adopted in many countries
– Germany, Finland, Singapore, Korea, Australia and others
– Included in the US OpenCable standard
• Many other broadcasters & content developers working with MHP

47. What Is MHP?
• Three main standards are related to MHP
– MHP 1.0.x (1.0.0 – 1.0.3)
• The original MHP specification plus updates
• The most commonly deployed version of MHP
– MHP 1.1.x
• Adds some new elements
• HTML support, stored applications, Internet client APIs, smart
card APIs
• Still a work in progress
– Globally Executable MHP (GEM)
• A subset of MHP 1.0.2
• Designed to form the basis of other DTV middleware standards
• Currently used by OCAP, ACAP and ARIB B23

48. Types of MHP Application
• Information services
– super teletext, etc.
• Show-related interactivity
– online quiz show, online voting, etc.
• Games
• T-commerce and banking
• Internet access

49. Building MHP Services
• Applications are built in Java or HTML
– Most of products use Java only
• Transported in a DVB transport stream
– Transport stream with DVB tables
• Transported in IP connection

50. What Can An Application
Do?
• MHP application can be supported by follow APIs
– Most of standard Java APIs
– Extensions for TV-specific functionality
– APIs for accessing return channel
– APIs for controlling and communicating applications
• HTML application support for latest internet standards
– XHTML, CSS 2.0, ECMAScript

51. MHP deployment
• MHP 1.0.2 deployed in:
– Finland
– Germany
– Italy
– South Korea
• Other countries will follow soon
– Australia, USA (through OCAP)
• MHP 1.1 is not currently deployed
– Too many problems remaining
– Not enough need for the additional features
• Usually other ways to get what you need

52. Interactive TV

53. outline
• Research about interactive TV
• The requirements
• The proposed system or model
• The evaluation or results
• conclusion

54. Research about interactive
TV
• Four papers are presented here
– Interactive TV: VoD meets the Internet
– MiTV: rethinking interactive TV
– An integrated live interactive content insertion
system for digital TV commerce
– Open graphical framework for interactive TV

55. The introduction
• Interactive TV: VoD meets the Internet
– Shim, S.S.Y.; Yen-Jen Lee;
– Computer , Volume: 35 , Issue: 7 , July 2002
– Pages:108 - 109

56. What is interactive TV?
• Television commerce combines the
interactive power of the internet with
traditional TV programming.
• Two ways to deliver VoD services:
– Focus on TV
– Focus on PC

57. Generic architecture for
interactive VoD
• Back-end-service
– Video server platform
• Support unicast or multicast at broadband rates.
• Consist of a streaming server engine , real-time
streaming file system , etc.
– Security manager
• User profiles and usage histories
– Program scheduler
• Responding to user interaction

58. Generic architecture for
interactive VoD (cont’d)
• Database
– To store metadata and are used on video
retrieval.
• Service applications
– E-commerce transaction
– Messaging platform

59. Generic architecture for
interactive VoD (cont’d)
• Client platform
– There are various device to present multimedia
stream to client side.
– Web-based management and rendering
applications can reside in an STB , a PC or a
PDA.
– The details will be discussed in the next section.

60. Generic architecture for
interactive VoD (cont’d)
The generic interactive architecture

61. Combining other devices to
interactive TV
• MiTV: rethinking interactive TV
– Bing, J.; Dubreuil, J.; Espanol, J.; Julia, L.; Lee,
M.; Loyer, M.; Serghine, M.;
– Virtual Systems and Multimedia, 2001.
Proceedings. Seventh International Conference
on , 25-27 Oct. 2001
– Pages:365 - 369

62. Traditional interface for iTV
• The shortage of traditional iTV
– When Interactive event happened , the audience
can not carry on browsing the original program.
– Co-watchers
– Feedback
• Answering questions
– Entering data
• No suitable devices

63. A new interaction paradigm
• A natural device that comes with the TV is its
remote.
• The switch mode is efficient for TV with
100+ channel (change channels by forward
and back ).
• Using mobile devices like PDA or tablet to
replace remote control may be a better way.

64. The foundations
• The CAB (Collaobrative Architecture of
BravoBrava! )infrastructure.
• It’s used for established communications
between the mobile devices and interactive
TV.
• Based on Microsoft’s DCOM architectures.

65. Applications of MiTV
• TV guide on pocket PC

66. Applications of MiTV
(cont’d)
• TV guide on a tablet

67. The pop-up information
• Showing logos on mobile devices instead of
on screen can keep the completeness of view
area.

68. Some examples of
interactive TV games
• The audience can join a interactive TV game by receiving
information and sending their answers by tablet or PDA.

69. Some examples of interactive
TV games (cont’d)
• Using hand-writing to answer quiz.

70. Example of an interactive
game meant for kids

71. Example of TV shopping

72. The third part
• An integrated live interactive content
insertion system for digital TV commerce
– Liang-Jie Zhang; Jen-Yao Chung; Lurng-Kuo
Liu; Lipscomb, J.S.; Qun Zhou;
– Multimedia Software Engineering, 2002.
Proceedings. Fourth International Symposium on
, 11-13 Dec. 2002
– Pages:286 - 293

73. introduction
• MPEG-2 is the video format used in digital TV. there are
three types of digital TV formats:
– ATSC
• Advanced television systems committee scheme
– DVB
• Digital video broadcast
– ARIB
• Association of radio industries an business

74. Introduction (cont’d)
• The problem of effectively organize the
interactive content and deliver its data in a
timely fashion to an mpeg-2 data injector.
• This paper proposed an improved method for
inserting interactive content into a live TV.

75. Digital TV commerce
solution
• Interactive solution

76. System architecture of the
integrated system for live data
insertion
• System architecture

77. Software based
implementation flow
• Dataflow diagram

78. The HotMedia TV Live

79. Interactive content
creation engine (ICCE)
• The authors provide an ICCE engine to
convert the online product list on the e-
commerce server.
• And combine some control (java script) to
the web part in interactive TV.

80. Interactive content
creation engine (cont’d)
• A sample of the
converted HTML

81. Scheduling
• Time-action mapping list
– 10/10/2000, 10:21:30, 3
– 10/10/2000, 10:40:30, 5
• Event-action mapping list
– PROGRAM_START, 5
– PROGRAM_END, 4
– COMMERCIAL_END, 3
– COMMERCIAL_START, 4

82. The final part
• Open graphical framework for interactive TV
– Cesar, P.; Vierinen, J.; Vuorimaa, P.;
– Multimedia Software Engineering, 2003.
Proceedings. Fifth International Symposium on ,
10-12 Dec. 2003
– Pages:21 - 28

83. introduction
• This paper focus on development of
framework and emphasize on cross platform
• So they choose JAVA for implementation
and Linux platform for performance.

84. System architecture
requirements
• User experience
• Developer experience
• Core architecture
• Adaptability

85. Classic architecture
• User Interface software components

86. Evaluation themes
• Here are some interesting terms they defined
to evaluate UI software tools.
– Focus
– threshold
– Ceiling
– Path of least resistance

87. The digital television
standard
• Various DVB , they are popular in Europe
– DVB-S (satellite)
– DVB-T (terrestrial)
– DVB-C (cable)
– DVB-MHP (multimedia home platform )

88. The architecture models
• Graphical architecture model and MHP setup

89. The proposed system
• Navigator application

90. The proposed system
(cont’d)
• Teletext application

91. The proposed system
(cont’d)
• SMIL television application

92. Summary