High-definition television
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High-definition television (HDTV) is a digital television broadcasting system with greater resolution than traditional television systems (NTSC, SECAM, PAL). HDTV is digitally broadcast, because digital television (DTV) requires less bandwidth if sufficient video compression is used. HDTV technology was introduced in the United States in the 1990s by the Digital HDTV Grand Alliance, a group of television companies.<ref>the Grand Alliance includes AT&T, General Instrument, MIT, Philips, Sarnoff, Thomson, and Zenith)</ref><ref name="spectrum">Modèle:Cite journal</ref>
History of high-definition television
In 1949, France launched 819 lines television, first high definition public television network (778 active lines). This 819 lines network remained operational until 1983.[citation needed]
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In 1983, the International Telecommunication Union ITU-R set up a working party (IWP11/6) with the aim of setting a single international HDTV standard. This WP considered many views and through the 1980s served to encourage development in a number of video digital processing areas such as conversion between 30/60 and 25/50 picture rates using motion vectors that led to other outcomes. While a single standard was never finalized, a common aspect ratio of 16:9 was agreed to at the first meeting at the BBC's R & D establishment at Kingswood Warren. Initially the Japanese 5:3 ratio was considered but a proposal to widen it to 5 1/3:3 = 16:9 was accepted. The ITU-R Recommendation BT.709 includes 16:9, colorimetry and the 1080i (1,080 actively-interlaced lines of resolution) and the 1080p (1,080 progressively-scanned lines). It also included the 1440 x 1152 HDMAC scanning format. 720p formats were strongly resisted by some ITU-R members and were not standardized there. Both 1920 x 1080 and 1280 x 720p (720 progressively-scanned lines) systems for a range of frame and field rates are also defined by several SMPTE standards.
No matter how hard developers tried, and despite the over 20 different standards proposed, high definition television lacked the basics of any successful media application; that is the means of distributing it.
Early HDTV commercial experiments such as NHK's MUSE required over four times the bandwidth of a standard definition broadcast, and despite the effort made to shrink the required bandwidth into about 2 times of that of the SDTV's, it still was distributable only by satellite. In addition, recording and reproducing an HDTV signal was also a technical challenge in the early years of HDTV. Nevertheless, the first HDTV sets went on sale in the United States in 1998. However, it was not until the first decade of the new millennium that storage means of enough capacity and computer processing power for dense compression algorithms made commercial applications of HDTV affordable for consumers and profitable for TV channels or the video rental industry.
Digital HDTV was finally viable due to the evolution of TV broadcasting, where the broadcasting systems all over the world were designed from scratch to use digital means of transmission. Thus, through digital compression equipment, and the evolution of standards such as MPEG 2, H264, a single TV channel could be used either for broadcasting up to 5 TV programs of standard definition, or for broadcasting up to 2 channels of high definition.
High-definition television refers to the image resolution and, loosely, to photo- and videographic media capable of such image resolution, i.e. photographic film and digital video. Current HDTV broadcast standards are in the ATSC and DVB specifications. HDTV is capable of cinema-quality audio, because it uses the Dolby Digital (AC-3) format to support the 5.1 surround sound system.
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HDTV sources
The rise in popularity of large screens and projectors has made the limitations of conventional Standard Definition TV (SDTV) increasingly evident. An HDTV compatible television set will not improve the quality of SDTV channels. To display a superior picture, high definition televisions require a High Definition (HD) signal. Typical sources of HD signals are as follows:
- Over the air with an antenna. Most cities in the US with major network affiliates broadcast over the air in HD. To receive this signal an HD tuner is required. Most newer high definition televisions have an HD tuner built in. For HDTV televisions without a built in HD tuner, a separate set-top HD tuner box can be rented from a cable or satellite company or purchased.
- Cable television companies often offer HDTV broadcasts as part of their digital broadcast service. This is usually done with a set-top box or CableCARD issued by the cable company. Alternatively one can usually get the network HDTV channels for free with basic cable by using a QAM tuner built into their HDTV or set-top box. Some cable carriers also offer HDTV on-demand playback of movies and commonly viewed shows.
- Satellite-based TV companies, such as DirecTV and Dish Network (both in North America), Sky Digital (in the UK and Ireland), Bell ExpressVu (in Canada) and NTV Plus (in Russia), offer HDTV to customers as an upgrade. New satellite receiver boxes and a new satellite dish are often required to receive HD content.
- Video game systems, such as the Xbox (NTSC only), Xbox 360, Playstation 2 (Gran Turismo 4) and Playstation 3 can output an HD signal. The Xbox Live Marketplace and Playstation Network services offers HD movies, TV shows, movie trailers, and clips for download to their respective consoles.
- Most newer computer graphics cards have either HDMI or DVI interfaces, which can be used to output images or video to an HDTV.
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Notation
HDTV broadcast systems are defined threefold, by:
- The number of lines in the vertical display resolution.
- The scanning system: progressive scanning (p) or interlaced scanning (i). Progressive scanning redraws an image frame (all of its lines) when refreshing each image. Interlaced scanning redraws the image field (every second line) per each image refresh operation, and then redraws the remaining lines during a second refreshing. Interlaced scanning yields greater image resolution if subject is not moving, but loses up to half of the resolution and suffers "combing" artifacts when subject is moving.
- The number of frames per second or fields per second.
The 720p60 format is 1280 × 720 pixels, progressive encoding with 60 frames per second (60 Hz). The 1080i50 format is 1920 × 1080 pixels, interlaced encoding with 50 fields per second. Sometimes interlaced fields are called half-frames, but they are not, because two fields of one frame are temporally shifted. Frame pulldown and segmented frames are special techniques that allow transmitting full frames by means of interlaced video stream.
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A frame or field rate can also be specified without a resolution. For example 24p means 24 progressive scan 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.
Standard Display Resolutions
Modèle:Contradict Image:Standard video res.svg
Video Format (WxH) | Name | Description |
720×576 | 576i | Used on D1/DV PAL |
704×576 | 576p | Used on EDTV PAL |
720×480 | 480i | Used on DV NTSC |
720×486 | 480i | Used on D1 NTSC (ITU-R 601) |
704×480 | 480p | Used on EDTV NTSC |
When resolution is considered, both the resolution of the transmitted signal and the (native) displayed resolution of a TV set are taken into account. Digital NTSC- and PAL/SECAM-like signals (480i60 and 576i50 respectively) are transmitted at a horizontal resolution of 720 or 704 "pixels".
However these transmitted DTV "pixels" are not square, and have to be stretched for correct viewing. PAL TV sets with an aspect ratio of 4:3 use a fixed pixel grid of 768 × 576 or 720 × 540; with an aspect ratio of 16:9 they use 1440 x 768, 1024 × 576 or 960 × 540; NTSC ones use 640 × 480 and 852 × 480 or, seldom, 720 × 540.
High-Definition Display Resolutions
High Definition usually refers to 720 vertical lines of resolution or more.
Resolution (WxH) | Pixels | Aspect Ratio | Video Format | Description |
1024×768 | 786,432 | 16:9 (non-square pixels) | 720p/XGA | Used on PDP HDTV displays with non square pixels |
1280×720 | 921,600 | 16:9 | 720p/WXGA | Used on Digital television, DLP, LCD and LCOS projection HDTV displays |
1366×768 | 1,049,088 | 16:9 | 720p/WXGA - HDTV standard format | Used on LCD/PDP HDTV displays (HD Ready, HD Ready 720p,1080i) |
1024×1080 | 1,105,920 | 16:9 (non-square pixels) | 1080p | Used on PDP HDTV displays (Full HD, HD Ready 1080p) |
1280×1080 | 1,382,400 | 16:9 (non-square pixels) | 1080p | Used on PDP HDTV displays (Full HD, HD Ready 1080p) |
1920×1080 | 2,073,600 | 16:9 | 1080p - HDTV standard format | Used on all types of HDTV technologies (Full HD, HD Ready 1080p) |
4096x2160 | 8,847,360 | 16:9 | 2160p DCI Cinnema 4k standard format | Quad HDTV, (there is no HD Ready 2160p Quad HDTV format) |
Modèle:Cleanup-section hd1080i.blogspot.com/2006/12/1080i-on-1366x768-resolution-problems.html|title=1366x768 resolution problems on HDTV, HD-Ready, and High Definition TV}}</ref> pixels instead of the ATSC Standard 1280 x 720 pixels. This is due to maximization of manufacturing yield and resolution of VGA, VRAM that comes with a 768 pixel format. Hence, LCD manufacturers adopt the 16:9 ratio compatible for the HD Ready 1080p standard. Nevertheless, every HDTV has an overscan processing chipset to fix resolution scaling and color rendering, eg LG XD Engine, SONY BRAVIA Engine. Only when viewing 1080i/1080p HD contents under HD Ready 1080p where there is true pixel-for-pixel reproduction, and for HD ready LCD TV, do some signals undergo a scaling process which results in a 3-5% loss of picture.//hd1080i.blogspot.com/2006/12/1080i-on-1366x768-resolution-problems.html|title=1366x768 resolution problems on HDTV, HD-Ready, and High Definition TV}}</ref> pixels instead of the ATSC Standard 1280 x 720 pixels. This is due to maximization of manufacturing yield and resolution of VGA, VRAM that comes with a 768 pixel format. Hence, LCD manufacturers adopt the 16:9 ratio compatible for the HD Ready 1080p standard. Nevertheless, every HDTV has an overscan processing chipset to fix resolution scaling and color rendering, eg LG XD Engine, SONY BRAVIA Engine. Only when viewing 1080i/1080p HD contents under HD Ready 1080p where there is true pixel-for-pixel reproduction, and for HD ready LCD TV, do some signals undergo a scaling process which results in a 3-5% loss of picture.
Standard frame or field rates
- 23.976p (allow easy conversion to NTSC)
- 24p (cinematic film)
- 25p (PAL, SECAM DTV progressive material)
- 30p (29.97p in drop frame) (NTSC DTV progressive material)
- 50p (PAL, SECAM DTV progressive material)
- 60p (59.94p in drop frame) (NTSC DTV progressive material)
- 50i (PAL & SECAM)
- 60i (59.94i in drop frame) (NTSC, PAL-M)
Broadcast station format considerations
Close-up view | |
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Image:HDTV example - Fish 40x46 squares.svg | Image:Raster graphic fish 20x23squares sdtv-example.png |
HDTV resolution | SDTV resolution |
At the least, HDTV has twice the linear resolution of standard-definition television (SDTV), thus showing greater detail than either analog television or regular DVD. The technical standards for broadcasting HDTV also handle the 16:9 aspect ratio images without using letterboxing or anamorphic stretching, thus increasing the effective image resolution.
The optimum format for a broadcast depends upon the type of videographic recording medium used and the image's characteristics. The field and frame rate should match the source and the resolution. A very high resolution source may require more bandwidth than available in order to be transmitted without loss of fidelity. The lossy compression that is used in all digital HDTV storage and transmission systems will distort the received picture, when compared to the uncompressed source.
Types of medium
The high resolution photographic film used for cinema projection is exposed at the rate of 24 frames per second. Depending upon available bandwidth and the amount of detail and movement in the image, the optimum format for video transfer is either 720p24 or 1080p24. When shown on television in PAL system countries, film must be projected at the rate of 25 frames per second by accelerating it by 4.1 per cent. In NTSC standard countries, the projection rate is 30 frames per second, a using a technique called 3:2 pull-down. One film frame is held for three video fields (1/20 of a second), and the next is held for two video fields (1/30 of a second) and then the process is repeated, thus achieving the correct film projection rate with two film frames shown in 1/12 of a second. Modèle:Cf.
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. Modèle:Seealso
Non-cinematic HDTV video recordings are recorded in either the 720p or the 1080i format. The format used is set by the broadcaster (if for television broadcast). In general, 720p is more accurate with fast action, because it progressively scans frames, instead of the 1080i, which uses interlaced fields and thus might degrade the resolution of fast images.
720p is used more for Internet distribution of high-definition video, because computer monitors progressively scan; 720p video has lower storage-decoding requirements than either the 1080i or the 1080p.
List of stations
- In Australia, the 576p50 format is also considered a HDTV format, as it has higher vertical resolution through the use of progressive scanning. When Australia started DVB-T in 2001 several networks broadcast high-definition in a 576p format as this could give better quality on 50Hz scanning CRT TVs and was not as demanding on MPEG-2 bit-rate. Now that flat-screens are predominating and these have an interlace to progressive scan conversion there is little difference in picture quality. Also MPEG-2 encoders have improved so the more conventional 720p and 1080i formats are now used. Technically, the 576p format is internationally defined as Enhanced-definition television and many DVD players can provide a 576p signal usually on HDMI outputs.
- In North America, Fox, My Network TV (both owned by the News Corporation), ABC, and ESPN (ABC and ESPN are both owned by Disney) currently broadcast 720p content. NBC, Universal HD (both owned by the NBC Universal subsidiary of General Electric and Vivendi), CBS, The CW (co-owned by CBS and Time Warner), HBO (owned by Time Warner), Showtime (owned by CBS), Starz!, MOJO HD, HDNet ,TNT(owned by Time Warner), CNN (also owned by Time Warner), and Discovery HD Theater currently broadcast 1080i content. In Canada, virtually all over-the-air HD stations broadcast 1080i, as do most cable specialty channels.
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- In the United Kingdom on Sky Digital, there are BBC HD, Sky One HD, Sky Arts HD, Sky Movies HD1 & 2, Sky Sports HD1,2 & X, Discovery HD, National Geographic Channel HD, The History Channel HD & Sky Box Office HD1 & 2. With MTV HD, FX HD, Living HD Rush HD, Ultra HD & Eurosport HD to come in the near future. BBC HD is also available on Virgin Media. The BBC Trust has given provisional approval for a BBC HD channel, which would be broadcast satellite, cable and DTT.
www.bbc.co.uk/bbctrust/consult/open_consultations/hdtv_consult.html Public consultation on the Trust's provisional conclusions on the proposed BBC HD service] is open until 23 October 2007.//www.bbc.co.uk/bbctrust/consult/open_consultations/hdtv_consult.html Public consultation on the Trust's provisional conclusions on the proposed BBC HD service] is open until 23 October 2007.
- In Brazil all 5 major TV networks (Band, Rede Globo, Rede Record, RedeTV! and SBT) and the public television started to broadcast HDTV (1080i) in December 2007. Brazil uses a mixture of the japanese HDTV system with Brazilian tecnology called SBTVD.
Technical details
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 AVC, such as the BBC which is trialing such a system via satellite broadcast, which will save considerable bandwidth compared to MPEG-2 systems. Some German broadcasters already use MPEG-4 AVC together with DVB-S2 (Pro 7, Sat.1 and Premiere). Although MPEG-2 is more widely used at present, it seems likely that in the future all European HDTV may be MPEG-4 AVC, and Norway, which is currently in the progress of implementing digital television broadcasts, is using MPEG-4 AVC for present SD Digital as well as for future HDTV on terrestrial broadcasts. In parts of Sweden the standard is already in use for HDTV terrestrial broadcasting, reaching about 25-30% of the population.
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, in which each pixel's height equals its width. New HD compression and recording formats such as HDV use rectangular pixels to save bandwidth and to open HDTV acquisition for the consumer market. For more technical details see the articles on HDV, ATSC, DVB, and ISDB.
Television studios as well as production and distribution facilities, use HD-SDI SMPTE 292M interconnect standard (a nominally 1.485 Gbit/s, 75-ohm serial digital interface) to route uncompressed HDTV signals. The native bitrate of HDTV formats cannot be supported by 6-8 MHz 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 Cinealta F23 & Thomson Viper), where one link/coax cable contains the 4:2:2 YCbCr info and the other link/coax cable contains the additional 0:2:2 CbCr information.
Advantages of HDTV expressed in non-technical terms
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High-definition television (HDTV) yields a better-quality image than does standard television, because it has a greater number of lines of resolution. Because the signal is a digital signal, it produces neither a snowy nor pale image from a weak signal or signal interference effects, such as herringbone patterns, or vertical rolling. Image colours are more realistic, because of the greater bandwidth. The visual information is some 2-5 times sharper because the gaps between the scan lines are narrower or invisible to the naked eye. Television content photographed and preserved on 35 mm film can be viewed at nearly its original resolution.
The lower-case "i" appended to the numbers denotes interlaced; the lower-case "p" denotes progressive. The interlaced scanning method, the 1,080 lines of resolution are divided into two, the first 540 lines are painted on a frame, the second 540 lines are painted on a second frame, reducing the bandwidth and increasing frame rate to 50-60 frames per second. The progressive scanning method simultaneously displays all 1,080 lines of resolution at 60 frames per second, on a greater bandwidth. (See: An explanation of www.pcworld.ca/Pages/NewsColumn.aspx?id=c0bcc80f0a01040800b24c9ac8d058ee HDTV numbers]//www.pcworld.ca/Pages/NewsColumn.aspx?id=c0bcc80f0a01040800b24c9ac8d058ee HDTV numbers] and www.pcworld.ca/Pages/NewsColumn.aspx?id=c0bcc80f0a01040800b24c9ac8d058ee HDTV numbers]//www.pcworld.ca/Pages/NewsColumn.aspx?id=a419bea40a010408019ac931bd202fb7 laymen's glossary])
Often, the broadcast HDTV video signal soundtrack is Dolby Digital 5.1 surround sound, enabling full, surround sound capabilities, while STBC television signals include either monophonic or stereophonic audio, or both. Stereophonic broadcasts can be encoded with Dolby Surround audio signal.
Disadvantages of HDTV expressed in non-technical terms
This article needs additional citations for verification. Please help improve this article by adding reliable references. Unsourced material may be challenged and removed. (December 2007) |
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.</ref> Also, image quality may be lost if the television is not properly connected to the input device or not properly configured for the input's optimal performance, which may be difficult because of customer confusion regarding connections.//www.widemovies.com/directvcomp.html|title=DirecTV HD Image Quality}}</ref> The operators may use format that is different from the original programming, introducing generation loss artifacts in the process of re-encoding.<ref> DirecTV's HD future is MPEG-4
.</ref> Also, image quality may be lost if the television is not properly connected to the input device or not properly configured for the input's optimal performance, which may be difficult because of customer confusion regarding connections.
As high-definition video broadcasts are digital, the disadvantages of digital video broadcasting also apply here. For example, digital video responds differently to analogue video when subject to interference. As opposed to a lower-quality signal one gets from interference in an analogue television broadcast, interference in a digital television broadcast will freeze, skip, or display "garbage" information. Broadcasters may aggressively compress video to save bandwidth and therefore broadcast more channels - this compression manifests itself as reduced video quality.
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As of 2007, broadcasters may demand, or cable-television operators may elect, to place HD signals in a premium band that requires higher cable fees. That some satellite companies offer the local HD channels as a service at additional cost (transmission comes from satellite) suggests to some broadcasters that on-air broadcasts of local HD signals must be a premium service to subscribers. Viewers may be denied some television channels that they expected, be allowed only access to the non-digital, and obviously sub-standard non-digital signal, or have to install an antenna to receive the digital broadcasts. Such issues more entail economic and legal disputes than they entail technology.
Another disadvantage of HDTV compared to traditional television has been consumer confusion stemming from the different standards and resolutions, such as 1080i, 1080p, and 720p. Complicating the matter have been the changes in television connections from component video, to DVI, then to HDMI. Finally, the HD-DVD vs. Blu-ray Disc high definition storage format war engenders even more animosity for consumers. The confusion has led to slower uptake of the technology as many people wait to see what becomes the "ultimate" de-facto standard.
Early systems
The term high definition described the television systems of the 1930s and 1940s beginning with the British 405-line black-and-white system, introduced in 1936; however, it and the American 525-line NTSC system established in 1941, were high definition in comparison with previous mechanical and electronic television systems. Today, the American 525-line NTSC system and the European 625-line PAL and SECAM systems are standard definition television, whereas the post–WWII French 819-line black-and-white system, was high definition in the contemporary sense, it required more bandwidth and was discontinued in 1986, a year after the final British 405-line broadcast.
Japan is the only country with successful commercial analog HDTV, known as "Hi-vision", featuring a 5:3 aspect ratio screen with 1,125 interlaced lines (1,035 active lines) at the rate of 60 fields per second. Elsewhere, in Europe, analog 1,125-line HD-MAC television failed in its test broadcasts in the early 1990s.
Contemporary systems
1. HDTV Monitor
2. HD satellite receiver
3. Standard satellite dish
4. HDMI cable, DVI-D and audio cables, or audio and component video cables
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High-definition image sources include terrestrial broadcast, direct broadcast satellite, digital cable, high definition discs (BD and HD DVD), internet downloads and the latest generation of video game consoles.
Recording and compression
HDTV can be recorded to D-VHS (Data-VHS), W-VHS (analog only), to a HDTV-capable digital video recorder (for example DirecTV's high-definition Digital video recorder, Sky HD's set-top box, Dish Network's VIP 622 or VIP 722 high-definition Digital video recorder receivers, or TiVo's Series 3 or HD recorders), or an HDTV-ready HTPC. Some cable boxes are capable of receiving or recording two broadcasts at a time in HDTV format, and HDTV programming, some free, some for a fee, can be played back with the cable company's on-demand feature. 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.
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Table of terrestrial HDTV transmission systems
Systems | ATSC | DVB-T | ISDB-T |
---|---|---|---|
Source coding | |||
Video | Main Profile syntax of ISO/IEC 13818-2 (MPEG-2 – Video) | ||
Audio | ATSC Standard A/52 (Dolby AC-3) | As defined in ETSI DVB TS 101 154 - as H.264 AVC and/or ISO/IEC 13818-2 (MPEG-2 – Layer II Audio) and/or Dolby AC-3 | ISO/IEC 13818-7 (MPEG-2 – AAC Audio) |
Transmission system | |||
Channel coding | |||
Outer coding | R-S (207, 187, t = 10) | R-S (204, 188, t = 8) | |
Outer interleaver | 52 R-S block | convolutional (I=12, M=17, J=1) | 12 R-S block |
Inner coding | rate 2/3 Trellis code | PCC: rate 1/2, 2/3, 3/4, 5/6, 7/8; constraint length = 7, Polynomials (octal) = 171, 133 | |
Inner interleaver | 12 to 1 Trellis code | bit-wise, frequency, selectable time | |
Data randomization | 16-bit PRBS | ||
Modulation | 8VSB (Only used for over the air transmission) 16VSB (Designed for cable, but rejected by the cable industry, cable TV uses 64QAM or 256QAM modulation as a de facto standard) | COFDM 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 |
TV resolution
References
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Cited references
General references
- www.pcworld.ca/Pages/NewsColumn.aspx?id=c0bcc80f0a01040800b24c9ac8d058ee HDTV numbers]//www.theinquirer.net/gb/inquirer/news/2007/12/02/brazil-stars-hdtv-transmissions Brazil begins HDTV transmissions with Japanese standard], from The Inquirer
- United States Federal Standard 1037C
- DTV channel protection ratios
- DVB HDTV standard
- www.pcworld.ca/Pages/NewsColumn.aspx?id=c0bcc80f0a01040800b24c9ac8d058ee HDTV numbers]//www.ebu.ch/en/technical/trev/trev_299-ive.pdf Images formats for HDTV], article from the EBU Technical Review .
- www.pcworld.ca/Pages/NewsColumn.aspx?id=c0bcc80f0a01040800b24c9ac8d058ee HDTV numbers]//www.ebu.ch/en/technical/trev/trev_300-wood.pdf High Definition for Europe - a progressive approach], article from the EBU Technical Review .
- www.pcworld.ca/Pages/NewsColumn.aspx?id=c0bcc80f0a01040800b24c9ac8d058ee HDTV numbers]//www.ebu.ch/CMSimages/en/tec_doc_t3299_tcm6-23327.pdf High Definition (HD) Image Formats for Television Production], technical report from the EBU
- www.pcworld.ca/Pages/NewsColumn.aspx?id=c0bcc80f0a01040800b24c9ac8d058ee HDTV numbers]//www.worldscreen.com/archivenews4.php?filename=harris421.htm TV Azteca Plans HDTV Mexican Rollout]_tcm
See also
- 480p, 576p, 720p, 1080i, 1080p
- 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)
- High-definition television in the United Kingdom
- Freesat
- High-definition television in the United States
- HDTV Blur
External links
- www.pcworld.ca/Pages/NewsColumn.aspx?id=c0bcc80f0a01040800b24c9ac8d058ee HDTV numbers]//www.dtv.gov/ US Government HDTV and DTV official site]
- www.pcworld.ca/Pages/NewsColumn.aspx?id=c0bcc80f0a01040800b24c9ac8d058ee HDTV numbers]//www.crtc.gc.ca/ Canadian Radio-television and Telecommunications Commission]
- www.pcworld.ca/Pages/NewsColumn.aspx?id=c0bcc80f0a01040800b24c9ac8d058ee HDTV numbers]//www.ce.org/Press/CEA_Pubs/821.asp CEA'S HDTV Guide]
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