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15 selected topics for e-learning technologies (dtv)

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15 selected topics for e-learning technologies (dtv)

  1. 1. Timothy K. Shih Selected Topics for e- Learning Technologies (Digital TV and MHP)
  2. 2. Digital TV technologies • Outline – Part1: Introduction to DTV – Part2: DTV receivers – Part3: MHP middleware – Part4: Interactive TV
  3. 3. Introduction to DTV
  4. 4. Introduction to DTV • Outline – DTV overview – Characteristic of DTV industry – DTV standard overview
  5. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 17. DTV overview • DTV Advanced Functions – MHP (Multimedia Home Platform) • A middleware • More applications than audio/video • Java-like applications
  18. 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. 19. Characteristic of DTV industry • Huge difference among different DTV markets – 1. Different DTV standards – 2. Different ecological dispersion – 3. Different market demands
  20. 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. 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. 22. Characteristic of DTV industry • DTV standards in the world wide
  23. 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. 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. 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. 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. 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. 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. 29. DTV receivers
  30. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 44. MHP middleware
  45. 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. 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. 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. 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. 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. 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. 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. 52. Interactive TV
  53. 53. outline • Research about interactive TV • The requirements • The proposed system or model • The evaluation or results • conclusion
  54. 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. 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. 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. 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. 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. 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. 60. Generic architecture for interactive VoD (cont’d) The generic interactive architecture
  61. 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. 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. 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. 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. 65. Applications of MiTV • TV guide on pocket PC
  66. 66. Applications of MiTV (cont’d) • TV guide on a tablet
  67. 67. The pop-up information • Showing logos on mobile devices instead of on screen can keep the completeness of view area.
  68. 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. 69. Some examples of interactive TV games (cont’d) • Using hand-writing to answer quiz.
  70. 70. Example of an interactive game meant for kids
  71. 71. Example of TV shopping
  72. 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. 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. 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. 75. Digital TV commerce solution • Interactive solution
  76. 76. System architecture of the integrated system for live data insertion • System architecture
  77. 77. Software based implementation flow • Dataflow diagram
  78. 78. The HotMedia TV Live
  79. 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. 80. Interactive content creation engine (cont’d) • A sample of the converted HTML
  81. 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. 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. 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. 84. System architecture requirements • User experience • Developer experience • Core architecture • Adaptability
  85. 85. Classic architecture • User Interface software components
  86. 86. Evaluation themes • Here are some interesting terms they defined to evaluate UI software tools. – Focus – threshold – Ceiling – Path of least resistance
  87. 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. 88. The architecture models • Graphical architecture model and MHP setup
  89. 89. The proposed system • Navigator application
  90. 90. The proposed system (cont’d) • Teletext application
  91. 91. The proposed system (cont’d) • SMIL television application
  92. 92. Summary

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