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High-definition television

Projection screen in a home theater, displaying a high-definition television image.

High-Definition television (HDTV) refers to the broadcasting of television signals with a higher resolution than traditional formats (NTSC, SECAM, PAL) allow. Except for early analog formats inEurope and Japan, HDTV is broadcast digitally, and therefore its introduction sometimes coincides with the introduction of digital television (DTV): this technology was first introduced in the USA during the 1990s, by the Digital HDTV Grand Alliance (grouping together AT&T, General Instrument, MIT, Philips, Sarnoff, Thomson, and Zenith).

HDTV is defined as 1080 active interlaced lines, or 720 progressive lines. 16 : 9 aspect ratio in ITU-R BT.709. The term "high-definition" can refer to the resolution specifications themselves, or to media capable of similar sharpness such as movie film.

Notation

In the context of HDTV, the formats of the broadcasts are referred to using a notation describing:
* The number of lines in the vertical display resolution.
* Whether progressive frames (p) or interlaced fields (i) are used.
* The number of frames or fields per second.

For example, the format 720p60 is 1280 × 720 pixels, progressive encoding with 60 frames per second (60 hertz known as Hz). The format 1080i50 is 1920 × 1080 pixels, interlaced encoding with 50 fields (25 frames) per second. Often the frame or field rate is left out, indicating only the resolution and type of the frames or fields. Sometimes the rate is then to be inferred from the context, in which case it can usually be assumed to be either 50 or 60, except for 1080p which is often used to denote either 1080p24, 1080p25 or 1080p30.

A frame or field rate can also be specified without a resolution. For example 24p means 24 progressive frames per second and 50i means 25 interlaced frames per second, consisting of 50 interlaced fields per second.

Most HDTV systems support some standard resolutions and frame or field rates. The most common are noted below.

Changes in Notation

It should be noted that the terminology described above was invented for digital systems in the 1990s. Before that, analog TV had no true "pixels" to measure horizontal resolution, and vertical scan-line count included off-screen scan lines with no picture information while the CRT beam returned to the top of the screen to begin another field. Thus NTSC was considered to have "525 lines" even though only 480 of them had a picture (625/576 for PAL). Similarly the Japanese MUSE system was called "1125 line", but is only 1035i by today's measuring standards. This change was made because digital systems have no need of blank retrace lines unless the signal was converted to analog to drive a CRT.

Standard resolutions

Visual comparison of common TV display resolutions.

Note: This diagram lists only a few common video resolutions based on specification. For real life video resolutions, subject to interlace artifacts, please view the diagram at the end of this article or the display resolution article.
* NTSC is 720 x 480 non-square pixels
* PAL is 720 x 576 non-square pixels (Note that the image above appears to be incorrect with regard to PAL vs. NTSC horizontal resolution.)

NTSC uses pixels that are narrower than square (0.912), PAL uses pixels that are wider than square (1.094). This is referred to as the CCIR-601 standard for digital video.

Standard frame or field rates

* 24p (cinematic film)
* 25p
* 30p
* 50p
* 60p
* 50i (PAL/SECAM)
* 60i (NTSC)

Comparison to SDTV

HDTV has at least twice the resolution of SDTV, thus allowing much more detail to be shown compared to analog television or regular . In addition, the technical standards for broadcasting HDTV are also able to handle 16:9 aspect ratio pictures without using letterboxing, thus further increasing the effective resolution for such content.

Close-up view

Image:Raster graphic fish 40X46squares hdtv-example.jpg|HDTV at four times the resolution of SDTV.Image:Raster graphic fish 20x23squares sdtv-example.jpg|SDTV resolution.

Format considerations

The optimum format for a broadcast depends on the type of media used for the recording and the characteristics of the content. The field and frame rate should match the source, as should the resolution. On the other hand, a very high resolution source may require more bandwidth than is available in order to be transmitted without loss of fidelity. The lossy compression that is used in all digital HDTV storage/transmission systems will then cause the received picture to appear distorted when compared to the uncompressed source.

Photographic film destined for the theater typically has a high resolution and is photographed at 24 frame/s. Depending on the available bandwidth and the amount of detail and movement in the picture, the optimum format for video transfer is thus either 720p24 or 1080p24. When shown on television in countries using PAL, film must be converted to 25 frames per second by speeding it up by 4.1%. In countries using the NTSC standard, (60 fps) a technique called 3:2 pulldown is used. One film frame is held for three video fields, (1/20 of a second) and then the next is held for two video fields (1/30 of a second) and then the process repeats, thus achieving the correct film rate with two film frames shown in 1/12 of a second. (See also: Telecine)

Older (pre-HDTV) recordings on video tape such as Betacam SP are often either in the form 480i60 or 576i50. These may be upconverted to a higher resolution format (720i), but removing the interlace to match the common 720p format may distort the picture or require filtering which actually reduces the resolution of the final output. (See also: Deinterlacing)

Non-cinematic HDTV video recordings are recorded in either 720p or 1080i format. The format depends on the broadcast company if destined for television broadcast; however, in other scenarios the format choice will vary depending on a variety of factors. In general, 720p is more appropriate for fast action as it uses progressive fields, as opposed to 1080i which uses interlaced fields and thus can have a degradation of image quality with fast motion. In addition, 720p is used more often with internet distribution of HD video, as all computer monitors are progressive, and most graphics cards do a poor job of de-interlacing video in real time. 720p Video also has lower storage and decoding requirements than 1080i or 1080p, and few people possess displays capable of displaying the 1920x1080 resolution without scaling. 720p appears at full resolution on a common 1280x1024 LCD, which can be found for under $250. An LCD capable of native 1080p resolution costs close to a thousand dollars.

In North America, Fox, ABC, and ESPN (ABC and ESPN are both owned by Disney) currently broadcast 720p content. NBC, Universal HD (both owned by General Electric), CBS, HBO-HD, INHD, HDNet and TNT currently broadcast 1080i content.

Technical details

One of the first DVB-S2 tuner cards.

MPEG-2 is most commonly used as the compression codec for digital HDTV broadcasts. Although MPEG-2 supports up to 4:2:2 YCbCr chroma subsampling and 10-bit quantization, HD broadcasts use 4:2:0 and 8-bit quantization to save bandwidth. Some broadcasters also plan to use MPEG-4. Some German broadcasters already use MPEG-4 together with DVB-S2 (ProSieben, Sat1 and Three Premiere Channels). Although MPEG-2 is more widely used at present, it seems likely that in the future all European HDTV may be MPEG-4 and Ireland and Norway, which have not yet started any Digital Television, is considering MPEG4 for SD Digital as well as HDTV on Terrestrial broadcasts.

HDTV is capable of "theater-quality" audio because it uses the Dolby Digital (AC-3) format to support "5.1" surround sound.

The pixel aspect ratio of native HD signals is a "square" 1.0, or 1 pixel length = 1 pixel width. New HD compression and recording formats such as HDV use rectangular pixels for more efficient compression and to open HDTV acquisition for the consumer market.

For more technical details see the articles on HDV, ATSC, DVB, and ISDB, respectively.

Within television studios and other production and distribution facilities, HD-SDI SMPTE 292M interconnect standard (a nominally 1.485 Gbit/s, 75-ohm serial digital interface) is used to route uncompressed HDTV signals. The native bitrate of HDTV formats cannot be supported by 6-8MHz standard-definition television channels for over-the-air broadcast and consumer distribution media, hence the widespread use of compression in consumer applications. SMPTE 292M interconnects are generally unavailable in consumer equipment, partially due to the expense involved in supporting this format, and partially because consumer electronics manufacturers are required (typically by licensing agreements) to provide encrypted digital outputs on consumer video equipment, for fear that this would aggravate the issue of video piracy.

Newer dual-link HD-SDI signals are needed for the latest 4:4:4 camera systems (Sony HDC-F950 & Thomson Viper), thereby one link/coax cable contains the 4:2:2 YCbCr info and the other link/coax contains the 0:2:2 additional CbCr information.

Advantages of HDTV expressed in non-engineering terms

#All commercial HD is digital, so the signal will either deliver an excellent picture, a picture with noticeable pixelation, a series of still pictures, or no picture at all. You would never get a snowy or washed out image from a weak signal, effects from signal interference, such as herringbone patterns, or vertical rolling.#Most HD programming and films will be presented in the 16:9 proportioned, semi-widescreen format (though some films created in even wider ratios will still display "letterbox" bars on the top and bottom of even 16:9 sets.) Older films and programming that retain their 4:3 ratio display will be presented in a version of letterbox commonly called "pillar box", displaying bars on the right and left of 16:9 sets (rendering the term "fullscreen" a misnomer). Or, one can usually choose to enlarge the image to fill the screen, however this option will display a distorted, stretched-out picture. #The colors will generally look more realistic, due to their greater bandwidth.#The visual information is about 2-5 times more detailed overall. The gaps between scanning lines are smaller or invisible. Legacy TV content that was shot and preserved on 35 mm film can now be viewed at nearly the same resolution as that at which it was originally photographed. #Two new pre-recorded disc formats support HDTV resolutions, namely HD DVD and Blu-ray (which both support up to 1080p). Players for both systems are expected to be backward-compatible with DVDs, however the two formats are not compatible with each other.#The increased clarity and detail make larger screen sizes more comfortable and pleasing to watch.#Dolby Digital 5.1 sound is broadcast along with standard HDTV video signals allowing full surround sound capabilities. (standard television signals broadcast basic stereo audio signals)

Early systems

The British 405-line system was the first to advertise itself as high definition and see widespread use. Most patents were expiring by the end of World War II leaving the market wide open and no worldwide standard for television agreed upon. The world used analog PAL, NTSC, SECAM and other standards for over half a century. Also, France used a different television system with over 755 interlaced lines of vertical resolution.

Japan was the only country where commercial analog HDTV was launched and had some success. In other places such as Europe's analog (HD-MAC) HDTV failed. Finally, although the United States experimented with analog HDTV (there were about 10 proposed formats), it soon moved towards a digital approach.

Contemporary systems

Asia

Hong Kong

Due to the city's cramped living conditions, flat panel widescreen TV monitors are very popular in Hong Kong. Many people enjoy widescreen DVD movies on their TVs despite the lack of HD broadcasts. While the local authorities have flagged end-2006 as the deadline for a decision to be made on which HDTV standard Hong Kong will adopt, there are political and business considerations. The mainland Chinese government will likely want to be able to jam TV signals from Hong Kong, so that Chinese citizens near the border cannot receive uncensored content from Hong Kong. Currently, analog TV signals from Hong Kong are delayed a few seconds before being relayed inland, such that content on banned topics such as Falun Gong and the Tiananmen Square Protests of 1989 can be blocked. By the same token, Hong Kong broadcasters are keen to use whichever standard China adopts, since doing so would allow them to transmit into the lucrative Southern China market and would lessen the need for costly format conversion.

Japan

Japan had pioneered HDTV for decades with an analog implementation. The old system is not compatible with the new digital standards. Japan terrestrial broadcast of HD via ISDB-T started in December 2003. It is reported that two million HD receivers have been sold in Japan already.

Republic of Korea

After a long controversy between the government and broadcasters, ATSC was chosen over DVB-T. From 2005, digital services are available across the entire country.

It is required that at least 10 hours of HD content to be broadcast on a weekly basis during the first year of commercial digital service.

Singapore

On Wednesday, May 31, 2006, Singapore kicked off the HDTV trials officially. Two Singaporean broadcasters were involved, Mediacorp (broadcasting HD in DVB-T) and Starhub CableVision (DVB-C). Both broadcast in 1080i , but at 50 Hz, inline with the traditional PAL frequency Singapore uses. Triallists were selected from applicants who have been applying since 2 weeks before May 31st 2006, and there are a total of 1,000 participants on the trial. These trials will end at the end of the year, presumably then, or before that, Starhub and Mediacorp will open it up to all subscribers to receive HD.

Australia

Australia started HD broadcasting in January 2001, but only in August 2003 was HD content mandated. Most cities in Australia that have a population of 40,000 or greater have at least one terrestrial DTV channel available (for example, Albany, Western Australia, has had DTV available since May 2005). However, most Australian DTV broadcasters are still experimenting with HDTV transmission and DTV delivery.

Europe

Commercial HDTV services began in 2004 with Euro1080, a Belgian MPEG2/DVB-S pay channel. As for 2006, there has been a slow but steady increase in the number of HD channels available to European viewers in many countries. Although most of these channels are pay TV, there are some free to air HD stations available (Pro 7 & SAT.1), as well as technical transmissions by satellite.

HD Ready logo

The UK's first HDTV service began on 2 December 2005 when Telewest, a cable TV company now part of NTL, distributed HDTV programs to 400 customers in the south London area. On 10 March 2006 NTL confirmed that HDTV was available nationally in the former Telewest areas. Sky High-Definition became available to subscribers from 1 May 2006.

Throughout 2006, the British Broadcasting Corporation (BBC) has been running http://www.bbc.co.uk/digital/tv/hdtv.shtml HDTV broadcast tests across digital platforms in preparation for the launch of BBC HD. Broadcasts on BBC HD will include the BBC drama series Bleak House and Hotel Babylon, Planet Earth, the 2006 FIFA World Cup tournament and selected 2006 Wimbledon matches. As of July 2006, the BBC transmissions were using H.264/MPEG-4 AVC at 1080i but with a horizontal resolution of 1440 pixels (see HDV) rather than the standard 1920 pixels. More information is available from the BBC Press OfficeIn autumn, the new Polish digital platform ITI Neovision will start 3 commercial HD stations, where one of them show all Premier League matches. It will also introduce DVR, VOD and MHP. The video of a press conference is availbable from the [1].

A label "HD-ready" has been created to inform consumers of the benefits of High Definition. The purpose of the label is to create a single norm to simplify the purchase of a HDTV in Europe. Compliant sets accept all current SD and HD resolutions at 50- and 60-hertz rates, they need to have a native resolution of at least 720 lines at a 16:9 aspect ratio.

North America

Canada

In Canada, on November 22 2003, CBC had their first broadcast in HD, in the form of the Heritage Classic outdoor NHL game between the Edmonton Oilers and the Montreal Canadiens. Bell ExpressVu, a Canadian satellite company, Rogers Cable and Videotron provide somewhat more than 21 HDTV channels to their subscribers including TSN HD, SportsNet HD, Discovery HD (Canadian Edition), The Movie Network HD, and several U.S. stations plus some PBS feeds and a couple of pay-TV movie channels. CTV Toronto broadcast in HD along with its western counterpart, BC CTV. They were also the first to broadcast a terrestrial HD digital ATSC signal in Canada. Global joined the crowd in late 2004. Other networks are continuing to announce availability of HD signals. CHUM Limited's Citytv in Toronto was the first HDTV broadcaster in Canada; however, now most cable and satellite subscribers across Canada can access multiple channels in HDTV with major American and Canadian affiliate stations broadcasting HDTV signals with no CANCON overlay for advertising. Typically these channels are NBC HD, ABC HD, CBS HD, FOX HD, TSN HD, Sportsnet HD, CBC HD etc. as of Summer 2006. CBC HD officially launched their HDTV programming on March 5 2005. CBC HD broadcasts the first game of their Hockey Night In Canada Saturday double header in HDTV. The 2006 NHL Playoff games have seen an increased amount of HDTV coverage as well. StarChoice, another Canadian satellite provider, currently offers its subscribers 14 HDTV channels at no extra cost. Shaw Cable has found limited success with HDTV implementation since the cost of a HD PVR is near the $650 CAD mark. Monthly rentals for this equipment have helped HDTV adoption rates.

Mexico

Mexican television company Televisa made experimental HDTV broadcasts in the early-1990s, in collaboration with Japan's NHK. Some events now broadcast in high definition.

During the first half of 2005, at least one cable provider in Mexico City (Cablevision) has begun to offer 5 HDTV channels to subscribers purchasing a digital video recorder (DVR).

In 2005, TV Azteca signed a deal with Harris Corporation's broadcast communications division for digital TV transmitters and HDTV encoding equipment to bring high-definition TV to nine Mexican cities.

The launch will be carried out in two phases. By the third quarter of 2006, HDTV transmissions will be available in Mexico's largest markets: Mexico City, Guadalajara and Monterrey. Phase Two of the national rollout will bring HDTV services to six cities along the Mexico-U.S. border (Matamoros, Reynosa, Nuevo Laredo, Ciudad Juarez, Mexicali and Tijuana) through the first half of 2006. This rollout takes advantage of HDTV receivers already in place thanks to an earlier HDTV rollout by stations on the American side of the border.

Also, TV Azteca has planned to broadcast the Mexican football tournament in HDTV. And almost all retailers have started shipping televisions with HDTV tuners.

XETV in Tijuana, Baja California - across the border from San Diego, California - is on the air in HDTV using 720p format. This affiliate of the American Fox TV Network is on UHF channel 23 broadcasting from Mt. San Antonio in Tijuana, Mexico with 403,000 watts, directed primarily northward at San Diego. In January 2006, Televisa's XEFB-TV and Multimedios' XHAW-TV in Monterrey, Nuevo Leon began HDTV transmissions on UHF channels 48 and 50, respectively. In February 2006, Televisa's XHUAA in Tijuana began its HDTV transmissions on channel 20. Unfortunately they have no HDTV programs. Channel 20 broadcasts an upconverted version of the programs of XHUAA's analog signal on channel 57. In Guadalajara, Televisa channels 2 (XHGA HD),4 (XHG HD) and 9 (XEWO HD) are available in 1080i format, TV Azteca channels 31 and 33 broadcast in 480i format.

United States



In the United States, HDTV specifications are defined by the ATSC. An HDTV-compatible TV usually uses a 16:9 aspect ratio display with an integrated ATSC tuner. Lower-resolution sources like regular DVDs may be upscaled to the native resolution of the TV. It is estimated that by the end of 2006, 10% of American TVs will be HDTVs, but in the same survey, 83% of Americans are not satisified with the HDTV they are getting. The FCC has mandated that all broadcast must be in digital starting on February 17, 2009. The original deadline of January 1, 2006 was abolished when it was realized that TV stations and customers would not be able to meet the earlier deadline.

South America

Argentina

While HDTV-ready TVs sales are increasing in this country, no single HD feed is available right now.The government is still deciding which format will be used, but chances are American's ATSC will be chosen.Directv and local cable company "Cablevision" may also offer HDTV decoders and channel pack later this year.

Brazil

Since 2001 native 480p TVs are commercialized in Brazil mainly for DVD video support. In 2003 the first 1080i models were introduced (being capable to rescaling 720p) and native 720p LCD monitors in 2004 reached the market.

The Brazilian government took a while to ponder which standard to choose, but at June 29 2006 the President Luis Inácio Lula da Silva signed a decree choosing ISDB as a national standard, strangely based on something not so transmission-related - the promise of construction of a semiconductor factory in the country financed by NEC, Sony, Panasonic and Toshiba.

The transition to ISDB will take 9 years so far, the manufacturers will adopt the new standard for the new TV's and also will be available a converter to buy, so the people can continue using their ISDB-incompatible TV's with the new transmission system.

The Japanese government studies the implementation of few improvements on the standard suggested by Brazilian researchers. These new features are very unlikely to be adopted in Japan due to incompatibility problems, but are being considered to be used in future implementations in other countries including Brazil itself.

Uruguay

While HDTV-ready TV sets are available at the country, a few factors seem to constraint the development of the new technology in the near term:
* Prices for LCD, Plasma and DLP based TV sets can be two times more expensive in Uruguay than in the region, or four times more expensive than the US, while wages are also lower than in the region. Some DLP based display can cost up to U$S 7000 in Uruguay. There have been few examples, if any, of CRT-based HDTV sets. Taxes seem to play a huge factor in the high prices.
* The cable industry has then few incentives to provide other services beyond basic TV services: Internet-by-cable and cable-telephony have been either strictly prohibited by law or by high taxes on equipment that make a bussines case for newer technologies unfeasible. Digital Cable has stared rolling out, with an initial 100% increase of monthly cost for the SD digital service. High HDTV tv-set prices do not help. Some of the cable companies for the largest markets are also owned by the largest local TV content providers, which also as of 2006 have not started producing any HDTV content publicly.
* DirecTV might be in the better standing to provide HDTV content, given that they have experience and content from the US and given that they serve the whole continent. But DirecTV's policy in Uruguay has been that of providing "leftover" equipment from Argentina to its customers in Uruguay (i.e.: First generation RCA receivers), which as of now do not support HDTV content, or Dolby AC-3 Sound. Uruguayan DirecTV customers have no way of buying an alternative DirecTV set, other than the provided by DirecTV representatives.
* Uruguay argued to have some hope on neighboring countries reaching an agreement on an HDTV standard, but so far that does not seem to be the case. Brazil has adopted the ISDB System, while Argentina and Uruguay have historically used european-standard based TV systems (PAL-N 625/50Hz). Now, Argentina seems to be closing on the ATSC standard, and no news are out from Uruguayan URSEC authorities on which road they will get. The TV sets being sold in Uruguay seem to be closer to ATSC HDTV-based standards (60Hz systems). If a 50 Hz standard is adopted, consumers that bought 60Hz might get hurt if there is a lack of compatibility on the sets being sold. Most of the DVD based content in the country is NTSC/60Hz based, while the TV standard in use is PAL/50Hz based. Most of the analog TV sets sold are PAL-N,PAL-M and NTSC capables, while most DVD players are multiregion. Authorities are not asking the retailers to identify to which standard the HDTV sets sold adhere to, or require them to warn consumers that Uruguay has not yet set on a a given HDTV standard. Most tech-savvy consumers feel uneasy about buying (either for themselves or hinting friends) such high-priced TV sets with such a large set of doubts surrounding HDTV standards in the country.

Recording, compression

HDTV can be recorded to D-VHS (Digital-VHS), W-VHS (analog MUSE only), to an HDTV-capable digital video recorder such as DirecTV's high-definition TiVo or Dish Network's DVR 921, 942 or VIP622, or to a computer equipped with an HDTV capture card. In the U.S., the only current archival option is D-VHS. D-VHS digitally records a 28.2-Mbit stream onto a classic VHS tape, using a FireWire (IEEE 1394) digital transport to carry a compressed MPEG-2 Transport Stream from the tuning device to the recorder.

However, the massive amount of data storage required to archive uncompressed streams make it unlikely that an uncompressed storage option will appear in the consumer market soon. Realtime MPEG-2 compression of an uncompressed digital HDTV signal is also prohibitively expensive for the consumer market at this time, but should become inexpensive within several years (although this is more relevant for consumer HD camcorders than recording HDTV). Analog tape recorders with bandwidth capable of recording analog HD signals such as W-VHS recorders are no longer produced for the consumer market and are both expensive and scarce in the secondary market.

As part of the FCC's "plug and play" agreement, cable companies are required to provide customers that rent HD set-top boxes with a set-top box with "functional" Firewire (IEEE 1394) upon request. None of the direct broadcast satellite providers have offered this feature on any of their supported boxes, but some cable TV companies have. As of July 2004, boxes are not included in the FCC mandate. This content is protected by encryption known as 5C. . This encryption can prevent someone from recording content at all or simply limit the number of copies.

Table of terrestrial HDTV transmission systems

Main characteristics of three DTTV systems
SystemsATSC DVB-T ISDB-T
Source coding
Video Main Profile syntax of ISO/IEC 13818-2 (MPEG-2 – Video)
AudioATSC Standard A/52 (Dolby AC-3)ISO/IEC 13818-2 (MPEG-2 – Layer II Audio) and Dolby AC-3ISO/IEC 13818-7 (MPEG-2 – AAC Audio)
Transmission system
Channel coding-Outer codingR-S (207, 187, t = 10) R-S (204, 188, t = 8)
Outer interleaver52 R-S block 12 R-S block
Inner codingrate 2/3 Trellis code PCC: rate 1/2, 2/3, 3/4, 5/6, 7/8; constraint length = 7, Polynomials (octal) = 171, 133
Inner interleaver12 to 1 Trellis codebit-wise, frequencybit-wise, frequency, selectable time
Data randomization 16-bit PRBS
Modulation8-VSB and 16-VSBCOFDM
QPSK, 16QAM and 64QAM
Hierarchical modulation: multi-resolution constellation (16QAM and 64QAM)
Guard interval: 1/32, 1/16, 1/8 & 1/4 of OFDM symbol
Two modes: 2k and 8k FFT
BST-COFDM with 13 frequency segments
DQPSK, QPSK, 16QAM and 64QAM
Hierarchical modulation: choice of three different modulations on each segment
Guard interval: 1/32, 1/16, 1/8 & 1/4 of OFDM symbol
Three modes: 2k, 4k and 8k FFT

References

* United States Federal Standard 1037C
* DTV channel protection ratios
* DVB HDTV standard
*Images formats for HDTV, article from the EBU Technical Review .
*High Definition for Europe - a progressive approach, article from the EBU Technical Review .
*High Definition (HD) Image Formats for Television Production, technical report from the EBU
*Digital Terrestrial HDTV Broadcasting in Europe , technical report from the EBU
* TV Azteca Plans HDTV Mexican Rollout

References

See also

* Advanced Television Systems Committee (ATSC)
* ATSC tuner
* Integrated Services Digital Broadcasting
* DVB (Digital Video Broadcasting)
* Digital television
* HDTV input and colorspace (YPbPr/YCbCr).
* HD ready
* SDTV (Standard Definition Television)
* Ultra-High Definition Video (UHDV)
* Middleware High Definition support: OpenTV HD

External links


* DTV government Resource US Government HDTV and DTV official site
* HDTV Information Consumer information about HDTV
* ATSC
* CDTV Canadian Digital Television official website



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