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DVB

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The official logo of the DVB Project, often used to signify compliance with DVB standards.

Digital Video Broadcasting(DVB) is a set of internationalopen standardsfordigital television.DVB standards are maintained by theDVB Project,an international industry consortium,[1]and are published by a Joint Technical Committee (JTC) of theEuropean Telecommunications Standards Institute(ETSI),European Committee for Electrotechnical Standardization(CENELEC) andEuropean Broadcasting Union(EBU).

Transmission[edit]

DVB systems distribute data using a variety of approaches, including:

These standards define thephysical layeranddata link layerof the distribution system. Devices interact with the physical layer via a synchronous parallel interface (SPI), synchronous serial interface (SSI) orasynchronous serial interface(ASI). All data is transmitted inMPEG transport streamswith some additional constraints (DVB-MPEG). A standard for temporally-compressed distribution to mobile devices (DVB-H) was published in November 2004.

These distribution systems differ mainly in themodulationschemes used and error correcting codes used, due to the different technical constraints. DVB-S (SHF) usesQPSK,8-PSK or 16-QAM.DVB-S2 uses QPSK, 8-PSK, 16-APSK or 32-APSK, at the broadcasters decision. QPSK and 8-PSK are the only versions regularly used. DVB-C (VHF/UHF) usesQAM:16-QAM, 32-QAM, 64-QAM, 128-QAM or 256-QAM. Lastly, DVB-T (VHF/UHF) uses 16-QAM or 64-QAM (or QPSK) in combination with(C)OFDMand can supporthierarchical modulation.

The DVB-T2 specification was approved by the DVB Steering Board in June 2008 and sent to ETSI for adoption as a formal standard. ETSI adopted the standard on 9 September 2009.[2]The DVB-T2 standard gives more robust TV reception and increases the possible bit rate by over 30% for single transmitters (as in the UK) and will increase the maximum bit rate by over 50% in largesingle-frequency networks(as in Germany andSweden).

DVB has established a 3D TV group (CM-3DTV) to identify "what kind of 3D-TV solution does the market want and need, and how can DVB play an active part in the creation of that solution?" The CM-3DTV group held a DVB 3D-TV Kick-off Workshop in Geneva on 25 January 2010, followed by the first CM-3DTV meeting the next day.[3]DVB now defines a new standard for 3D video broadcast:DVB 3D-TV.

Modes and features of latest DVB-x2 system standards in comparison:

DVB-S2 DVB-T2 DVB-C2
Inputinterface Multipletransport streamandgeneric stream encapsulation(GSE) Multiple transport stream and generic stream encapsulation (GSE) Multiple transport stream and generic stream encapsulation (GSE)
Modes Variable coding& modulation andadaptive coding& modulation Variable coding & modulation[4] Variable coding & modulation and adaptive coding & modulation
FEC LDPC+BCH1/4, 1/3, 2/5, 1/2, 3/5, 2/3, 3/4, 4/5, 5/6, 8/9, 9/10 LDPC + BCH 1/2, 3/5, 2/3, 3/4, 4/5, 5/6 LDPC + BCH 1/2, 2/3, 3/4, 4/5, 5/6, 8/9, 9/10[5]
Modulation Single carrier,PSKorAPSK,multiple streams OFDM absolute OFDM[6]
Modulation schemes QPSK, 8-PSK, 16-APSK, 32-APSK QPSK, 16-QAM,64-QAM, 256-QAM 16- to 4096-QAM
Guard interval Not applicable 1/4, 19/256, 1/8, 19/128, 1/16, 1/32, 1/128 1/64 or 1/128
Fourier transform size Not applicable 1k, 2k, 4k, 8k, 16k, 32kDFT 4kInverse FFT[7]
Interleaving Bit-Interleaving Bit- time- and frequency-interleaving Bit- time- and frequency-interleaving
Pilots Pilot symbols Scattered and continual pilots Scattered and continual pilots

Content[edit]

Digital videocontent is encoded usingdiscrete cosine transform(DCT) basedvideo coding standards,such as theH.26xandMPEGformats.Digital audiocontent is encoded usingmodified discrete cosine transform(MDCT) basedaudio coding standards,such asAdvanced Audio Coding(AAC),Dolby Digital(AC-3) andMP3.

Besidesdigital audioanddigital videotransmission, DVB also defines data connections (DVB-DATA -EN301 192) withreturn channels(DVB-RC) for several media (DECT,GSM,PSTN/ISDN,satelliteetc.) and protocols (DVB-IPTV:Internet Protocol;DVB-NPI: network protocol independent).

Older technologies such asteletext(DVB-TXT) andvertical blanking intervaldata (DVB-VBI) are also supported by the standards to ease conversion. However, for many applications more advanced alternatives like DVB-SUB for subtitling are available.

Encryption and metadata[edit]

Theconditional accesssystem (DVB-CA) defines aCommon Scrambling Algorithm(DVB-CSA) and a physicalCommon Interface(DVB-CI) for accessingscrambledcontent. DVB-CA providers develop their wholly proprietary conditional access systems with reference to these specifications. Multiple simultaneous CA systems can be assigned to a scrambled DVB program stream providing operational and commercial flexibility for the service provider.

DVB is also developing a Content Protection and Copy Management system for protecting content after it has been received (DVB-CPCM), which is intended to allow flexible use of recorded content on a home network or beyond, while preventing unconstrained sharing on the Internet. DVB-CPCM has been the source of much controversy in the popular press and it is said that CPCM is the DVB's answer to the failed AmericanBroadcast Flag.[8]

DVB transports includemetadatacalled Service Information (DVB-SI, ETSI EN 300 468, ETSI TR 101 211) that links the various elementary streams into coherent programs and provideshuman-readabledescriptions forelectronic program guidesas well as for automatic searching and filtering. The dating system used with this metadata suffers from ayear 2038 problemin which due to the limited 16 bits andmodified Julian dayoffset used will cause an overflow issue similar to theyear 2000 problem.By comparison, the rivalDigiCipher 2basedATSCsystem will not have this issue until 2048 due in part to 32 bits being used.[citation needed]

Recently, DVB has adopted a profile of the metadata defined by theTV-AnytimeForum (DVB-TVA, ETSI TS 102323). This is an XML Schema based technology and the DVB profile is tailored for enhancedPersonal Digital Recorders.DVB lately also started an activity to develop a service forIPTV(DVB-IPI, ETSI TR 102033, ETSI TS 102034, ETSI TS 102814) which also includes metadata definitions for a broadband content guide (DVB-BCG, ETSI TS 102 539).

Software platform[edit]

TheDVB Multimedia Home Platform(DVB-MHP) defines aJava-based platform for the development of consumer video system applications. In addition to providing abstractions for many DVB andMPEG-2concepts, it provides interfaces for other features like network card control, application download, and layered graphics.

Return channel[edit]

DVB has standardized a number of return channels that work together with DVB(-S/T/C) to create bi-directional communication. RCS is short forReturn Channel Satellite,and specifies return channels inC,KuandKafrequency bands with return bandwidth of up to 2Mbit/s. DVB-RCT is short forReturn Channel Terrestrial,specified by ETSI EN 301958.

Service discovery[edit]

The DVB-I standard (ETSI TS 103 770) defines an internet-based request and response mechanism to discover and access audiovisual services delivered over traditional digital broadcast transmissions or Internet Protocol networks and present them in a unified way.[9]

Adoption[edit]

DTT broadcasting systems.

DVB-S and DVB-C were ratified in 1994. DVB-T was ratified in early 1997. The first commercial DVB-T broadcasts were performed by theUnited Kingdom'sDigital TV Groupin late 1998. In 2003Berlin,Germanywas the first area to completely stop broadcasting analogue TV signals. Most European countries are fully covered by digital television and many have switched offPAL/SECAMservices.

DVB standards are used throughoutEurope,as well as inAustralia,South AfricaandIndia.They are also used for cable and satellite broadcasting in mostAsian,Africanand manySouth Americancountries. Some have chosen ISDB-T instead of DVB-T and a few (United States,Canada,MexicoandSouth Korea) have chosen ATSC instead of DVB-T.

Africa[edit]

Kenya[edit]

DVB-T broadcasts were launched by thePresident of Kenya,Mwai Kibakion 9 December 2009. Broadcasts are usingH.264,with theUniversity of Nairobisupplying the decoders.Kenyahas also been broadcasting DVB-H since July 2009, available on selectedNokiaandZTEhandsets on theSafaricomand other GSM networks.[10]

Madagascar[edit]

Since 2011, the pay TV operator Blueline[11]launched a DVB-T service branded BluelineTV.[12]It supplies both smart cards and set-top-boxes.

South Africa[edit]

Since 1995, the pay TV operatorDStvused the DVB-S standard to broadcast its services. In 2010, it started a DVB over IP service, and in 2011 it started DStv mobile using the DVB-H standard.[13]

In late 2010, the South African cabinet endorsed a decision by aSouthern African Development Community(SADC) task team to adopt the DVB-T2 standard.[14]

Asia[edit]

Hong Kong[edit]

InHong Kong,several cable TV operators such asTVB Pay VisionandCable TVhave already started using DVB-S or DVB-C. The government however has adopted theDMB-T/Hstandard, developed inmainland China,for its digital terrestrial broadcasting services which has started since 31 December 2007.[15]

Iran[edit]

On 17 March 2009, DVB-H and DVB-T H.264/AAC broadcasting started inTehranby theIRIB.DVB-T broadcasting is now widely available in other cities such asIsfahan,Mashhad,Shiraz,Qom,TabrizandRashtas well.

Israel[edit]

DVB-T broadcasts usingH.264commenced inIsraelon 1 June 2009 with the broadcast trial and the full broadcast began on 2 August 2009. Analog broadcasts were originally planned to end in 18 months after the launch, but analog broadcasts were switched off on 31 March 2011 instead.

During 2010, DVB-T broadcasts have become widely available in most of Israel and an EPG was added to the broadcasts.[16]

Japan[edit]

With the exception ofSKY PerfecTV!,Japanuses different formats in all areas (ISDB), which are however quite similar to their DVB counterparts. SkyPerfect is a satellite provider using DVB on its 124 and 128 degrees east satellites. Its satellite at 110 degrees east does not use DVB, however.

Malaysia[edit]

InMalaysia,a new pay television stationMiTVbegan service in September 2005 usingDVB-IPTVtechnology while lone satellite programming providerASTROhas been transmitting in DVB-S since its inception in 1996. Free-to-air DVB-T trials began in late 2006 with a simulcast of both TV1 and TV2 plus a new channel called RTM3/RTMi. In April 2007, RTM announced that the outcome of the test was favourable and that it expected DVB-T to go public by the end of 2007. However, the system did not go public as planned. As of 2008, the trial digital line-up has expanded to include a music television channel calledMuzik Aktif,and a sports channel called Arena, with a news channel called Berita Aktif planned for inclusion in the extended trials soon. Also, high definition trials were performed during the Beijing Olympics and the outcome was also favourable. It was announced that the system would go public in 2009.

In 2009, MiTV closed down, changed its name to U-Television and announced that it was changing to scrambled DVB-T upon relaunch instead of theDVB-IPTVsystem used prior to shutting down. However, RTM's digital network again did not go public, although around this time TVs that are first-generation DVB-T capable went on sale. The government has since announced that they will be deploying DVB-T2 instead in stages starting in mid-2015 and analog shutoff has been delayed to April 2019.

Philippines[edit]

In thePhilippines,DVB-SandDVB-S2are the two broadcast standards currently used by satellite companies, whileDVB-Cis also used by some cable companies. The government adoptedDVB-Tin November 2006 for digital terrestrial broadcasting but a year later, it considered other standards to replace DVB-T. The country has chosen theISDB-Tsystem instead ofDVB-T.

Taiwan[edit]

InTaiwan,some digital cable television systems use DVB-C, though most customers still use analogue NTSC cable television. The government planned adopting ATSC or the Japanese ISDB-T standard as NTSC's replacement. However, the country has chosen the European DVB-T system instead. Public Television Service (PTS) and Formosan TV provide high definition television. The former has the channel HiHD; the latter uses its HD channel for broadcasting MLB baseball.

Europe[edit]

Cyprus[edit]

Cyprususes DVB-T with MPEG-4 encoding. Analogue transmission stopped on 1 July 2011 for all channels exceptCyBC 1.

Denmark[edit]

InDenmark,DVB-T replaced the analog transmission system for TV on 1 November 2009. Danish national digital TV transmission has been outsourced to the company Boxer TV A/S,[17]acting as gatekeeper organization for terrestrial TV transmission in Denmark.[18][19]However, there are still several free channels fromDR.

Finland[edit]

DVB-T transmissions were launched on 21 August 2001. The analogue networks continued alongside the digital ones until 1 September 2007, when they were shut down nationwide. Before the analogue switchoff, the terrestrial network had three multiplexes: MUX A, MUX B and MUX C. MUX A contained the channels of the public broadcasterYleisradioand MUX B was shared between the two commercial broadcasters:MTV3andNelonen.MUX C contained channels of various other broadcasters. After the analogue closedown, a fourth multiplex named MUX E was launched. All of theYleisradio(YLE) channels are broadcast free-to-air, likewise a handful of commercial ones includingMTV3,Nelonen,Subtv,Jim,Nelonen Sport,Liv,FOX,TV5Finland,AVAandKutonen.There are also several pay channels sold byPlusTV.

Italy[edit]

In Italy, DVB-S started in 1996 and the final analogue broadcasts were terminated in 2005. The switch-off from analogue terrestrial network to DVB-T started on 15 October 2008. Analogue broadcast was ended on 4 July 2012 after nearly four years of transition in phases.

Netherlands[edit]

In theNetherlands,DVB-S broadcasting started on 1 July 1996, satellite provider MultiChoice (nowCanalDigitaal) switched off the analogue service shortly after on 18 August 1996. DVB-T broadcasting started April 2003, and terrestrial analog broadcasting was switched off December 2006. It was initially marketed byDigitennebut later byKPN.Multiplex 1 contains theNPO 1,NPO 2andNPO 3national TV channels, and a regional channel. Multiplexes 2~5 have the other encrypted commercial and international channels. Multiplex 1 also broadcasts the radio channels Radio 1, Radio 2, 3 FM, Radio 4, Radio 5, Radio 6, Concertzender, FunX and also a regional channel. As of June 2011, the Dutch DVB-T service had 29 TV channels and 20 radio channels (including free to air channels). DVB-T2 will be introduced during 2019/2020.

Norway[edit]

InNorway,DVB-T broadcasting is marketed under RiksTV (encrypted pay channels) andNRK(unencrypted public channels). DVB-T broadcasting via the terrestrial network began in November 2007, and has subsequently been rolled out one part of the country at a time. The Norwegian implementation of DVB-T is different from most others, as it usesH.264withHE-AACaudio encoding, while most other countries have adapted the less recentMPEG-2standard. Notably most DVB software for PC has problems with this, though in late 2007 compatible software was released, likeDVBViewerusing thelibfaad2library.Sonyhas released several HDTVs (Bravia W3000, X3000, X3500, E4000, V4500, W4000, W4500, X4500) that support Norway's DVB-T implementation without use of a separateset-top box,and Sagem ITD91 HD, Grundig DTR 8720 STBs are others.

Poland[edit]

Currently,Polanduses the DVB-T2 standard with HEVC encoding. Analogue broadcast switch-off started on 7 November 2012 and was completed on 23 July 2013.[20]

Portugal[edit]

Portugalfollows the DVB-T implementation, using H.264 with AAC audio encoding. It has been live since 29 April 2009 and the switch-off date for all analog signals was on 26 April 2012.

Romania[edit]

Romaniastarted digital terrestrial broadcasting in 2005 but it was virtually unknown by many people in Romania due to the lack of content, cable TV and satellite TV being far more popular, however it was the first platform to deliver HD content. Today, Romania is using DVB-T2 as terrestrial standard, but also DVB-S/S2, and DVB-C which is extremely popular. The only analogue broadcast remains on cable. Romania adopted the DVB-T2 standard in 2016 after a series of tests with mpeg2, mpeg4 on DVB-T, and has today fully implemented DVB-T2. DVB-C, which was introduced in late 2005, still remains with mpeg2 on SD content and mpeg4 on HD content. DVB-S (introduced in 2004 focus sat being the first such platform) is used in basic packages with standard definition content, while DVB-S2 set top boxes are provided for both SD and HD content.

Russia[edit]

Fully switched to digital in 2019,Russiauses the DVB-T2 standard for broadcasting 2 channel packs with about ten main national radio and TV channels (Channel One,Rossiya 1/2/K/24,NTV,Radio Mayak,Radio Rossiietc.

Spain[edit]

Quiero TVstarted digital terrestrial broadcasting in 2000 aspay television.The platform closed three years later after gaining 200,000 subscribers. The frequencies used by Quiero TV were used from 2005 to simulcastfree-to-airanalogue broadcast as DVB-T, under the name "TDT". The service started with 20 free-to-air national TV channels as well as numerous regional and local channles. Analogue broadcast ended on 2010 after getting 100% digital coverage. Some of the analogue frequencies were used to increase the number of channels and simulcast some of them in HD. Since February 14th, 2024, all channels will be required to broadcast exclusively in HD. Frequencies of SD channels will be used to simulcast some of them in 4K using DVB-T2.

United Kingdom[edit]

In the UK DVB-T has been adopted for broadcast of standard definition terrestrial programming, as well as a single DVB-T2 multiplex for high-definition programming. The UK terminated all analogue terrestrial broadcasts by the end of 2012. The vast majority of channels are availablefree-to-airthrough theFreeviewservice. DVB-T was also used for the now-defunctONDigital/ITV DigitalandTop Up TVservice.

All satellite programming (some of which is available free-to-air viaFreesatorfree-to-viewviaFreesat from Sky;the remainder requires a subscription toSky), is broadcast using either DVB-S or DVB-S2.

Subscription-based cable television fromVirgin Mediauses DVB-C.

North America[edit]

InNorth America,DVB-Sis often used in encoding andvideo compressionof digital satellite communications alongsideHughes DSS.UnlikeMotorola'sDigiCipher 2standard, DVB has a wider adoption in terms of the number of manufacturers of receivers. Terrestrial digital television broadcasts in Canada, Mexico, El Salvador, Honduras, and the United States use ATSC encoding with8VSBmodulation instead of DVB-T withCOFDM.Television newsgathering links from mobile vans to central receive points (often on mountaintops or tall buildings) use DVB-T with COFDM in the 2 GHz frequency band.

Oceania[edit]

Australia[edit]

InAustralia,DVB broadcasting is marketed under theFreeviewbrand name, and more recently 'Freeview Plus', denoting the integration of onlineHbbTVand EPG in certain DVB devices. Regular broadcasts began in January 2001 using MPEG 2 video and MPEG 1 audio[clarification needed]in SD and HD.

Changes to broadcasting rules have enabled broadcasters to offer multi-channeling, prompting broadcasters to use H.264 video with MPEG 1[clarification needed]or AAC audio encoding for some secondary channels.

Specifications for HD channels now differ depending on the broadcaster. ABC, Nine and Ten use 1920x1080i MPEG 4 video withDolby Digitalaudio. Seven and SBS use 1440x1080i MPEG 2 video with Dolby Digital and MPEG 1[clarification needed]respectively.[21]

New Zealand[edit]

InNew Zealand,DVB broadcasting is marketed under theFreeviewbrand name. SDMPEG-2DVB-S broadcasts via satellite began on 2 May 2007 and DVB-T (terrestrial) broadcasts began April 2008 broadcasting in HD H.264 video with HE-AAC audio.

South America[edit]

Colombia[edit]

Since 2008,Colombiahas adopted as a public policy the decision to migrate from the analog television implemented in 1954 toDigital Terrestrial Television(DVB-T2). This measure allows the viewers access to the open television (OTA) of public and private channels, with video quality inHD.As planned, analogue television broadcasts will end in 2021.

DVB compliant products[edit]

Companies that manufacture a product which is compliant to one or more DVB standards have the option of registering a declaration of conformity for that product. Wherever the DVB trademark is used in relation to a product – be it a broadcast, a service, an application or equipment – the product must be registered with the DVB project office.[22]

Related standards[edit]

Other international standards for digital broadcasting and reception includeATSC,originally from the US, andISDB,originally from Japan.

See also[edit]

References[edit]

  1. ^"DVB - Digital Video Broadcasting".www.dvb.org.Retrieved1 April2018.
  2. ^"Work Programme: Details of 'DEN/JTC-DVB-228' Work Item Schedule".ETSI.Retrieved29 August2010.
  3. ^"DVB - Digital Video Broadcasting - DVB 3D TV Kick-Off Workshop".Archived fromthe originalon 15 January 2010.Retrieved12 January2010.
  4. ^"Digital Video Broadcasting (DVB); Frame structure channel coding and modulation for a second generation digital terrestrial television broadcasting system (DVB-T2)"(PDF).DVB consortium. February 2011.
  5. ^"Digital Video Broadcasting (DVB); Frame structure channel coding and modulation for a second generation digital transmission system for cable systems (DVB-C2)"(PDF).DVB consortium. 7 May 2010.
  6. ^"Digital Video Broadcasting (DVB); Implementation Guidelines for a second generation digital cable transmission system (DVB-C2)"(PDF).DVB consortium. 19 November 2010.
  7. ^"DVB-C2 The second generation transmission technology for broadband cable"(PDF).Dirk Jaeger, Philipp Hasse, Joerg Robert, Institut fuer Nachrichtentechnik at Technische Universitaet Braunschweig. 8 April 2009. Archived fromthe original(PDF)on 2 April 2012.Retrieved24 January2013.
  8. ^"Europe's Broadcast Flag".Electronic Frontier Foundation. 29 September 2005. Archived fromthe originalon 13 October 2005.Retrieved15 August2007.
  9. ^"Digital Video Broadcasting (DVB): Service Discovery and Programme Metadata for DVB-I"(PDF).ETSI.November 2020.
  10. ^"Digital TV a reality in Kenya".Nation Media.Retrieved9 December2009.
  11. ^"Blueline Madagascar".www.blueline.mg.Retrieved1 April2018.
  12. ^BluelineTV
  13. ^"The MultiChoice Group".2 March 2023.
  14. ^"SA to adopt European TV standard: report".24.com.Retrieved18 January2011.
  15. ^"Digital TV".www.digitaltv.gov.hk.Archived fromthe originalon 21 July 2011.Retrieved1 April2018.
  16. ^"About - DVB".www.dvb.org.Retrieved1 April2018.
  17. ^"Fleksible tv-pakker og bredbånd hos Boxer - Tv-udbyder med valgfrihed".www.boxertv.dk.Retrieved1 April2018.
  18. ^"Kulturministeriets hjemmeside"(PDF).www.kum.dk.Retrieved1 April2018.
  19. ^"Kulturministeriets hjemmeside".www.kum.dk.Archived fromthe originalon 8 October 2009.Retrieved1 April2018.
  20. ^"General information about the digital broadcasting system in Poland".Ministry of Administration and Digitalization of Poland.Retrieved13 August2013.
  21. ^"ABC HD is now live".Australian Broadcasting Corporation.Retrieved27 December2016.
  22. ^Benoit, Herve. (2009).Digital Television: Satellite, Cable, Terrestrial, IPTV, Mobile TV in the DVB Framework.Taylor & Francis.ISBN978-1-136-02714-7.OCLC1024255874.

External links[edit]