Glasses

Scraping, fracturing, or breakage of the lenses require time-consuming and costly professional repair, though modern plastic lenses are almost indestructible and very scratch-resistant. Recording at 100 Mbits/s, it uses a better color compression method to give better color representation than a standard DV25 or MiniDV cassette and less compression artifacts. The lenses themselves can also become greasy or trap vapour when eating hot food or swimming or walking in rain, reducing visibility significantly. Broadcast-level HD cameras often record to hard-drives via a raw input/output or to tape or flash disks in formats that support higher bitrates than MiniDV cassettes such a DVCPro HD. Even though the late-20th century saw the creation of light frames, such as those made of titanium, very flexible frames, and new lens materials and optical coatings, glasses can still cause problems during rigorous sports. All major Camcorder vendors provide camcorders in this segment. Another unpopular aspect of glasses is their inconvenience. It records MPEG-2TS compressed HDTV video on standard DV media (DV or MiniDV cassette tape) and transfers it using Firewire.

Some people who find that wearing glasses may look nerdy turn to contact lenses instead, especially under peer pressure. The standard for consumer/prosumer HDTV acquisition is High-Definition Video (HDV). This conception probably comes from an era when most people were illiterate and the first people to wear glasses were those who did a lot of reading. Some DVD manufacturers such as Philips are licensing the DivX codec in order to play 720p/1080i content recorded on standard consumer DVD-R discs. An example of halo effect is seen in the stereotype that those who wear glasses are intelligent or, especially in teen culture, even geeks and nerds. This upconversion process can improve the perceived picture quality of standard-definition video. In popular culture, glasses were all the disguise Superman and Wonder Woman needed to hide in plain view as alter egos Clark Kent and Diana Prince, respectively. These players, however, are not considered to be true HD DVD players since they include only an integrated scaler to upconvert the standard-definition DVD video to high-definition video.

And of course John Lennon wore his round "granny glasses" from some of his time with the Beatles to his assassination in 1980. There are now some DVD players that will output enhanced or high-definition signals from standard-definition DVDs. Masaharu Morimoto wears glasses to separate his professional persona as a chef from his stage persona as Iron Chef Japanese. Although they disagree about physical format technology, both the HD DVD and Blu-ray factions have selected the same three video codecs to be mandatory in their designs: specifically, MPEG-2 Part 2, VC-1, and H.264. British comedic actor Eric Sykes, who became profoundly deaf as an adult, wears glasses that contain no lenses, but are in fact a bone-conducting hearing aid. The Blu-ray format has already gained a majority support from almost every major movie studio in the USA, while the HD DVD format has received support from a smaller consortium of companies, many of whom have also pledged support for Blu-ray anyway. Drew Carey continued to wear glasses for the same reason after getting corrective laser eye surgery. A more likely possibility is that the PlayStation 3 console (manufactured by Sony, the main advocate of Blu-ray discs) will gain a major lead in sales for Blu-ray players when it launches in 2006.

British soap star Anne Kirkbride had the same problem: her character on Coronation Street, Deirdre Barlow, became so well-known for her big frames that she was expected to wear them at social gatherings and in international tours, even though Kirkbride has always worn contact lenses. A possible outcome of a messy format war could be the emergence of combo players, as the physical disc sizes are identical. American Senator Barry Goldwater continued to wear lensless horn-rimmed spectacles after being fitted with contact lenses because he was not recognizable without his trademark glasses. As a result, this will likely lead to certain films becoming available only on one format. For some celebrities, glasses form part of their identity. Both sides of the HD disc camp are likely to leverage studio partners against each other through exclusive arrangements. Glasses can be a major part of personal expression, from the extravagance of Elton John and Dame Edna Everage, from Groucho Marx to John Denver to Lisa Loeb all the way to the varied professional personas of eyeglass-wearing knowledge workers. A format war is now very likely between the DVD Forum's HD DVD (formerly "Advanced Optical Disc") standard and the Blu-ray Disc Association's Blu-ray disc standard.

On the other hand, many people are attracted to people who wear glasses, and glasses are available in a wide range of styles, materials, and even designer labels. Recently, the DVD Forum and the Blu-ray Disc Association failed to agree on standards for high-definition 12-cm discs. Contact lenses also provide much improved peripheral vision. It was unclear to On2 and the arbitrator whether the Chinese government ever approved the EVD proposal as a standard. Glasses are often regarded as unattractive, and many people prefer to wear contact lenses for that reason. On2 filed multiple breach of contract claims for arbitration, but in March of 2005 the arbitrator ruled that E-World had not broken the contract and owed nothing to On2. Many people have several pairs of glasses, one for each task or distance, with specific glasses for reading, computer use, and television watching. Soon after the announcement that VP6 would be used on EVD, negotiations between On2 and E-World (the consortium pushing EVD to become a standard) broke down.

Others have lenses specifically intended for use with computer monitors at a fixed distance. studio will commit to movies in this format without some form of copy-protection, which is not yet specified. Some modern multifocal lenses give a smooth transition between these lenses, unnoticeable by most wearers. It is unlikely any major U.S. These were originally separate lenses, as invented by Benjamin Franklin. Very few titles were made available in any market for this format, although it is presumed that many would be needed to drive purchase of incompatible players. Traditional multifocal lenses have two or three distinct viewing areas, each requiring a conscious effort of refocusing. A low cost for the codec itself is not a significant advantage over DVD, however, as the standalone hardware players will be incompatible with standard DVD-Video unless the manufacturer pays the royalties for the technologies necessary to make the player DVD-compatible.

As people age, their ability to focus is lessened and many decide to use multiple-focus lenses, bifocal or even trifocal to cover all the situations in which they use their sight. As China starts to dominate manufacturing of TV and DVD units, the country's choice of standards becomes more important for everyone. Lenses can be ground to specific eyes, but in most cases standard off-the-shelf prescriptions suffice, but require custom-fitting to particular frames. As an advantage, VP6 would not require royalties on recorded media (although royalties would be charged for player devices at a similar cost as for other codecs). Magnifying lenses for reading that are used to treat mild hypermetropia and presbyopia can be bought off the shelf, but most glasses are made to a particular prescription, based on degree of myopia or hypermetropia combined with astigmatism. As reported, this was a result of China's desire to avoid royalties on WM9 or AVC. Glasses can be very simple. VP6 was reported by On2 to have been chosen by China for use in the Enhanced Versatile Disc (EVD) format initiative.

None of these conditions is considered a disease. H.264 is also used by some for encoding video podcasts. As most people age the crystalline lens of the eye loses elasticity resulting in presbyopia, which limits their ability to focus on nearby objects. Since many movie trailers are released in QuickTime format, when movie distributors started releasing HD trailers on the web the format they chose was H.264. Some would say "the rays of light converge at an imaginary point behind the retina." Astigmatism is a condition in which parallel rays of light entering the eye converge at two separate locations, either before and/or after the retina. H.264 has made significant progress towards becoming a widespread video format on the internet thanks to Apple Computer's QuickTime software supporting the format as of version 7. Hyperopia is a condition in which parallel rays of light entering the eye do not converge prior to reaching the retina. Example of broadcasters concerns.

Myopia is a condition in which parallel rays of light entering the eye converge before reaching to retina. However, this is currently a rumour and has not yet been challenged. Emmetropia, the condition of ideal focus is described as two parallel rays of light entering the eye and converging on or at the retina. In fact, there is some concern in the community that Microsoft may have appropriated itself the H.264 standard, modified and improved upon it and are trying to resell the solution as VC-1, without providing dues to the MPEG-LA. Glasses fitted with corrective lenses are a common means of correcting focus problems such as myopia (nearsightedness, short-sightedness) and hyperopia (farsightedness, long-sightedness). The main areas of dominance of VC-1 seem currently to be in the Blu-Ray DVD (HD DVD have not yet announced support for VC-1) and, for obvious reason, the home PCs. Virtual reality glasses and helmets have separate video screens for each eye and a method for determining the direction the head is turned. It has been thought for a while that VC-1 was better adapted for the IPTV world than H.264, but press announcements have also already been made by some of the largest STB manufacturers like Amino, Pace, Kreatel demonstrating solutions based on H.264 standards.

One kind of electronic 3D spectacles uses electronic shutters. So far, only a handful of very minor broadcasters are seriously considering VC-1. Another kind of 3D glasses uses polarized filters. H.264 was chosen for several reasons: The standard was validated as an open standard at least a year before VC-1 was seriously considered as a potential open standard, and, then, there is a lot of uncertainty on the levies Microsoft may want to impose once the algorithm is adopted. 3D glasses made of cardboard and plastic are distributed at 3D movies. H.264 as a standard has already been selected and adopted by the biggest broadcasters in the USA (DirecTV, DISH Network) and Europe (BSkyB, Premiere, Canal+, TPS, ...). The classic 3D glasses have one red lens and one blue lens. Other codecs are in contention such as AVC (MPEG-4 part 10, also known as H.264, approved by the ITU-T and MPEG standards bodies in early-2003) and the VP6 and now VP7 codecs from On2 Technologies.

Classic 3D glasses create the illusion of three dimensions when viewing specially prepared images. The codec has been submitted to SMPTE and is in SMPTE's standardization process with an intent for it to become an official SMPTE standard known as VC-1 in the near-future. The illusion of three dimensions on a two dimensional surface can be created by providing each eye with different visual information. As of the start of 2005, Microsoft recommends a 3.0 GHz processor with 512 MB of RAM and a 128-MB video card for 1080p playback on Windows XP, though they are now commercially available DVD players, like the KiSS DP-600, that will play back WMV HD DVD ROMs in high definition on HDTV sets. Polarized sunglasses may present some difficulties for pilots in that reflections from water and other structures often used to gauge altitude may be removed, or instrument readings on liquid crystal displays may be blocked. Since then, more titles have become available in this format, such as the acclaimed surf documentary Step Into Liquid. Popular among fishermen and hunters, polarized sunglasses allow wearers to see into water when normally glare or reflected light would be seen. As of November 2003, this format required a significant amount of processing power to encode and decode and the only commercially-available movie that used the codec was the Terminator 2: Extreme Edition DVD (see 1).

Polarization filters remove horizontal rays of light, which can cause glare. It remains to be seen if the codec will be adopted for widespread use, if only as a Wi-Fi industry standard. Light polarization is an added feature that can be applied to sunglass lenses. Microsoft is marketing its high-definition Windows Media 9 Series codec as WMV HD. Still, they offer the convenience of not having to carry both clear glasses and sunglasses to those who frequently go indoors and outdoors during the course of a day. In an attempt to provide a bitrate-compatible high-definition format for high-definition video on standard DVD-ROMs, Microsoft introduced their Windows Media 9 Series codec with the ability to compress a high-definition bitstream into the same space as a conventional NTSC bitstream (approximately 5 to 9 megabits per second for 720p and higher). Unfortunately, many car windshields protect the passengers from UV light, while not shielding from bright visible light, making photochromic lenses ineffective where they are most needed. It is expected to have a big impact on the HDTV market.

Glasses with photosensitive lenses, called photochromic lenses, become darker in the presence of UV light. Sony will include a Blu-ray player in PlayStation 3, and it will be released during 2006. Sunglasses vary greatly and many offer more style than protection. Blu-ray uses a blue-laser optical disc with an MPEG-2 or MPEG-4 codec. It is possible to have lenses that look very dark and yet offer little ultraviolet protection. Blu-ray technology is currently available only in Japan with a Japanese satellite/terrestrial tuner, but is expected to be released in other world markets in 2006. Due to changes in the atmosphere, ultraviolet levels are much higher than in the past and ultraviolet protection for eyes and skin is even more important. HD programming may be recorded on optical disc using Blu-ray or on HD DVD.

Good sunglasses should also protect against ultraviolet light. D-Theater is currently a small niche market even within the niche HDTV community, and it appears as if the final D-Theater title was published in 2004. plano) lenses that are darkened to provide protection against bright visible light. This format is superior to broadcast HDTV due to its higher bandwidth and, of course, the ability to do non-realtime optimization of the encoding, which is not possible with broadcast HDTV. Sunglasses may be made with either prescription or non-prescription (i.e. Comprising less than 100 titles and utilizing a 28-Mbit/s MPEG2 stream at 720p or 1080i with either Dolby Digital 5.1 or DTS encoding, D-Theater is an encrypted D-VHS format, and only D-Theater capable D-VHS players can play back these tapes. Main article: Sunglasses. Aside from scarce Japanese analog MUSE-encoded laser discs that are no longer produced, as of 2005 the only current available prerecorded HD media is D-Theater.

Corrective glasses with plastic lenses can often be used in the place of safety glasses in many environments; this is one advantage that they have over contact lenses. This encryption can prevent someone from recording content at all or simply limit the number of copies. The pictured wraparound safety glasses are evidence of this style change with the close fitting nature of the wraparound dispensing with the need for side shields. This content is protected by encryption known as 5C. Recent safety glasses have tended to be given a more stylish design, in order to encourage their use. As of July 2004, boxes are not included in the FCC mandate. They may provide less eye protection than goggles, face shields or other forms of eye protection, but their light weight increases the likelihood that they will actually be used. None of the DBS providers have offered this feature on any of their supported boxes.

Some safety glasses are designed to fit over corrective glasses or sunglasses. 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. The lenses of safety glasses can also be shaped for correction. 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. For example, those used in medicine may be expected to protect against blood splatter while safety glasses in a factory might have stronger lenses and a stronger frame with additional shields at the temples. 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). Safety glasses can vary in the level of protection they provide. 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.

Although safety lenses may be constructed from a variety of materials that vary in impact resistance, certain standards suggest that they maintain a minimum 1mm thickness at the thinest point regardless of material. 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. Safety glasses are usually made with shatter-resistant plastic lenses to protect the eye from flying debris. In the U.S., the only current archival option is D-VHS. Lenses made to conform to the prescription of an ophthalmologist or optometrist are called prescription lenses and are used to make prescription glasses. HDTV can be recorded to D-VHS (Data-VHS), W-VHS, to an HDTV-capable digital video recorder such as DirecTV's high-definition TiVo or Dish Network's DVR 921 or 942, or to a computer equipped with an HDTV capture card. Glasses correcting for myopia will have negative diopter strengths. Lower-resolution sources like regular DVDs may be upscaled to the native resolution of the TV.

Over-the-counter reading glasses are typically rated at +1.00 to +3.00 diopters. An HDTV-compatible TV usually uses a 16:9 aspect ratio display with an integrated ATSC tuner. The power of a lens is generally measured in diopters. In the United States, HDTV specifications are defined by the ATSC. Corrective lenses modify the focal length of the eye to alleviate the effects of shortsightedness (myopia), longsightedness (hyperopia) or astigmatism. Viewers without HDTV sets will continue to receive their television programming through analog transmission approaches. Either of these designs offers dramatically better ability to withstand the stresses of daily wear and the occasional accident. Viewers with HDTV sets will receive picture resolution six times sharper than standard definition analog sets.

Other frames have spring-loaded hinges. 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. For instance, it is now possible to purchase frames made of special memory metal alloys that return to their correct shape after being bent. San Antonio in Tijuana, Mexico with 403,000 watts, directed primarily northward at San Diego. Despite the increasing popularity of contact lenses and laser corrective eye surgery, glasses remain very common and their technology has not stood still. This affiliate of the American Fox TV Network is on UHF channel 23 broadcasting from Mt. These designs were not immediately successful, however, and various styles with attached handles such as scissors glasses and lorgnettes remained fashionable throughout the 18th and into the early 19th century. XETV in Tijuana, Baja California - across the border from San Diego, California - is on the air in HDTV using 720p format.

The modern style of glasses, held by temples passing over the ears, was developed in 1727 by the British optician Edward Scarlett. And one retailer, Elektra, started shipping televisions with HDTV receivers to support this broadcast. Girolamo Savonarola suggested that eyepieces could be held in place by a ribbon passed over the wearer's head, this in turn secured by the weight of a hat. Also, TV Azteca has planned to broadcast the Mexican football tournament in HDTV. Early eyepieces were designed to be either held in place by hand or by exerting pressure on the nose (pince-nez). Phase Two of the national rollout will bring HDTV services to six additional cities (Matamoros, Reynosa, Nuevo Laredo, Ciudad Juarez, Mexicali and Tijuana) through the first half of 2006. Over time, the construction of spectacle frames also evolved. By the third quarter of 2006, HDTV transmissions will be available in Mexico City, Guadalajara and Monterrey.

The first lenses for correcting astigmatism were constructed by the British astronomer George Airy in 1827. The launch will be carried out in two phases. The American scientist Benjamin Franklin, who suffered from both myopia and presbyopia, invented bifocals in 1784 to avoid having to regularly switch between two pairs of glasses. 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. However, it was not until 1604 that Johannes Kepler published in his treatise on optics and astronomy, the first correct explanation as to why convex and concave lenses could correct presbyopia and myopia. 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). Nicholas of Cusa is believed to have discovered the benefits of concave lens in the treatment of myopia (nearsightedness). Some events are now broadcast in high definition.

These early spectacles had convex lenses that could correct the farsightedness (presbyopia) that commonly develops as a symptom of aging. Mexican television company Televisa made experimental HDTV broadcasts in the early-1990s, in collaboration with Japan's NHK. Bacon's published writings describe the magnifying glass (which he did not invent), but make no mention of glasses. 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. Other stories, possibly legendary, credit Roger Bacon with the invention. From 2005, digital services are available in all the country. In 1738, a Florentine historian named Domenico Manni reported that a tombstone in Florence credited one Salvino d'Armato (died 1317) with the invention of glasses. After a long controversy between the government and broadcasters, ATSC was chosen over DVB-T.

Based on this evidence, Redi credited another Dominican monk, Fra Alessandro da Spina of Pisa, with the re-invention of glasses after their original inventor kept them a secret, a claim contained in da Spina's obituary record. It is reported that two million HD receivers have been sold in Japan already. In 1676, Franciscus Redi, a professor of medicine at the University of Pisa, wrote that he possessed a 1289 manuscript whose author complains that he would be unable to read or write were it not for the recent invention of glasses, and a record of a sermon given in 1305, in which the speaker, a Dominican monk named Fra Giordano da Rivalto, remarked that glasses had been invented less than twenty years previously, and that he had met the inventor. Japan terrestrial broadcast of HD via ISDB-T started in December 2003. The identity of the original inventor is unknown, although a possible source is the Arabs, who may have had magnifying lenses in the 10th century. The old system is not compatible with the new digital standards. Glasses were possibly invented in northern Italy, most likely in the late 1280s. Japan had pioneered HDTV for decades with an analog implementation.

. The purpose of the label is create a single norm to simplify the purchase of a HDTV in Europe. Sunglasses protect against high levels of visible and ultraviolet light. A label "HD-ready" has been created to inform consumers of the benefits of High Definition. Safety glasses are a kind of eye protection against flying debris or visible and near visible light or radiation. Although most of these channesl are pay tv, there are some free to air hd stations available(Prosieben & Sat 1), as well as technical transmissions by satellite. Corrective spectacles have lenses shaped to correct vision abnormalities, such as myopia. As for 2006, there has been a slow but steady increase in the number of HD channels available to european viewers in many countries.

Hydrophobic coatings designed to ease cleaning are also available, as are anti-reflective coatings intended to improve night vision and make the wearer's eyes more visible. Commercial HDTV services began in 2004 with Euro1080, an Belgian MPEG2/DVB-S pay channel. Scratch-resistant coatings can be applied to most plastic lenses giving them similar scratch resistance to glass. CBC officially launched HDTV programming on March 5, 2005. Some plastics have a greater index of refraction than most types of glass, allowing thinner lenses for a given prescription. as of early-2005. Some plastics also have more advantageous optical properties than glass, such as better transmission of visible light and greater absorption of ultraviolet light. CHUM Limited's Citytv in Toronto was the first HDTV broadcaster in Canada, however very few shows are shown in HDTV beyond the well-known ones such as CSI, ER, etc.

Glasses were originally made from glass, but many are now made from plastic (often polycarbonate or CR-39) due to the danger of breakage and the greater weight of glass lenses. Other networks are continuing to announce availability of HD signals. In hipster slang they are cheaters. Global joined the crowd in late-2004. Spectacles is often shortened to specs. They were also the first to broadcast a terrestrial HD digital ATSC signal in Canada. Glasses are more often called eyeglasses in North American English, occasionally spectacles in British English, and (rarely) frames or lenses. CTV Toronto broadcast in HD along with its western counterpart, BC CTV.

Historical types include the pince nez, monocle, and lorgnette. stations plus some PBS feeds and a couple of pay-TV movie channels. Modern glasses are typically supported by pads on the bridge of the nose and by temples placed over the ears. 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. Special glasses are used for viewing three-dimensional images or experiencing virtual reality. 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. Glasses, spectacles, or eyeglasses are frames bearing lenses worn in front of the human eyes, sometimes for purely aesthetic reasons but normally for vision correction or eye protection. A complete testbed is expected for 2006 (see http://sbtvd.cpqd.com.br/ for updates).

Eyeglasses were a common part of the hipster persona, for example Dizzy Gillespie. Brazilian universities, research and government institutions are discussing the best policies for a digital television system for use in Brazil. Cheaters is used in the hipster argot. However, most Australian DTV broadcasters are still experimenting with HDTV transmission and DTV delivery. Lenses is also sometimes used to refer to framed eyepieces, although it is not common. 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 for almost a year as of May, 2005). Frames is sometimes used to refer to framed eyepieces, although it is not common. Australia started HD broadcasting in January 2001, but only in August 2003 was HD content mandated.

In contrast, glass eye refers to a cosmetic prosthetic artificial eye that replaces a missing eye. See also: COUNCIL DIRECTIVE 92/38/EEC of 11 May 1992. Eye glasses or eyeglasses is a word used in North American English. The HD-MAC standard was abandoned in 1993, and since then all EU and EBU efforts have focused on the DVB system (Digital Video Broadcasting), which allows both SDTV and HDTV. Also in frequent use is the shortened form, specs. Thus, analogue HDTV could not replace conventional SDTV (terrestrial) PAL/SECAM, making HD-MAC sets unattractive to potential consumers. Spectacles is widely used in Britain and occasionally in the US, in addition to use by professional opticians. HD-MAC could be used only by cable and satellite providers, where there is a wider bandwidth available.

Compare with other meanings of the word glass. Another reason for HD-MAC's failure is that it was not realistic to use 36 MHz for a high-definition signal in terrestrial broadcasting (SDTV uses 6-, 7- (VHF), or 8-MHz (UHF)). Pair of glasses (or just glasses) is commonly used in Britain and in North America. HD-MAC (the high-definition variant of MAC) was left for transcontinental satellite links, however. Owing to the advance of technology and the launch of middle-powered satellites by SES Astra, broadcasters could avoid MAC, and lower transmission costs. It was required that all high-powered satellite broadcasters use MAC from that year.

However, it never became popular among broadcasters. The European Commission established a European standard for uncompressed digital HDTV in a 1986 directive (MAC). It broadcasts the same programs as BS-digital channel 103, but will end sometime in 2007. Though Japan has since switched to a digital HDTV system based on ISDB, the original MUSE-based BS Satellite channel 9 (NHK BS Hi-vision) is still being broadcast.

The Japanese MUSE system, developed by NHK Science and Technical Research Laboratories (STRL) in the 1980s, employed filtering tricks to reduce the original source signal to decrease bandwidth utilization. Japan began broadcasting analog HDTV signals in the early 1990s using an interlaced resolution of 1035 lines (1035i). Japan has the earliest working HDTV system still in use, with design efforts going back to 1979. It was transmitted only on VHF channels, and a French 819-line TV channel occupied 14 MHz of bandwidth.

It was used only for black-and-white TV; color TV in 819-line SECAM never went beyond the experimental stage. It was discontinued in 1986. The French "755i" 819-line HDTV system was used in only France, Belgium and Monaco, and in France only for the first French TV channel. When, in the late-1960s, a second TV channel and color TV were introduced in Europe, the UK dropped its 405-line TV system (completely in 1985) and France dropped its 819-line system, making all European countries agree to use 625 lines (576i) for their TV transmissions.

The French 819-line (or 755i) HDTV system was introduced in the 1950s. The French TV system thus became the world's first HDTV system, and, by today's standards, the French system could be called 755i (not all lines could be used for the actual image — some lines were lost during the vertical retrace). The UK used 405 lines, most other countries 625 lines (both numbers include the vertical gap, the actual resolution were lower), but France decided in 1948 to go for 819 lines. in the late-1940s and early-1950s, different countries used different resolutions.

When Europe resumed TV transmissions after WWII, i.e. Most professionals in 3D technology foresee greater use of stereo visuals and animation as HDTV becomes the norm. The Discovery HD channel has already provided a small amount of science programing in 3D. A number of 3D stereoscopic major animation films like Polar Express, Disney's Chicken Little and 6 more scheduled for 2006 release, will be likely to be sold for home display in one or more of the new HD disk systems in 3D.

For more technical details see the articles on HDV, ATSC, DVB, and ISDB, respectively. New HD compression and recording formats such as HDV use rectanglar pixels for more efficient compression and to open HDTV aquisition for the consumer market. The pixel aspect ratio of native HD signals is 1.0, or 1 pixel length = 1 pixel width. HDTV is capable of "theater-quality" audio because it uses the Dolby Digital (AC-3) format to support "5.1" surround sound.

Recommended receiver is Humax PR-HD 1000, but others are announced as well as PCI cards. Some German broadcasters already use MPEG-4 together with DVB-S2 (ProSieben, Sat1 and Three Premiere Channels). Some broadcasters also plan to use MPEG-4. Although MPEG-2 supports up to 4:2:2 YUV chroma subsampling and 10-bit quantization, HD broadcasts use 4:2:0 and 8-bit quantization to save bandwidth.

MPEG-2 is most commonly used as the compression codec for digital HDTV broadcasts. NBC, Universal-HD (both owned by General Electric), CBS, HBO-HD, INHD, HDNet and TNT currently broadcast 1080i content. In North America, Fox, ABC, and ESPN (ABC and ESPN are both owned by Disney) currently broadcast 720p content. An LCD capable of native 1080i resolution still costs over a thousand US dollars.

720p appears at full resolution on a common 1280x1024 LCD, which can be found for under $250. 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. 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 sub-optimal job of de-interlacing video in real time. 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 degredation of image quality with fast motion.

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. Noncinematic HDTV video recordings are recorded in either 720p or 1080i format. (See also: Deinterlacing). 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.

Older (pre-HDTV) recordings on video tape such as Betacam SP are often either in the form 480i60 or 576i50. (See also: Telecine). 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. In countries using the NTSC standard, (60 fps) a technique called 3:2 pulldown is used.

When shown on television in countries using PAL, film must be converted to 25 frames per second by speeding it up by 4%. 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. Photographic film destined for the theatre typically has a high resolution and is photographed at 24 frame/s. The lossy compression that is used in all digital HDTV systems will then cause the picture to be distorted.

On the other hand, a very high resolution may require more bandwidth than is available. The field and frame rate should match the source, as should the resolution. The optimum format for a broadcast depends on the type of media used for the recording and the characteristics of the content. 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.

HDTV has at least twice the resolution of SDTV, thus allowing much more detail to be shown compared to analog television or regular DVD. The most common are:. Most HDTV systems support some standard resolutions and frame or field rates. For example 24p means 24 progressive frames per second and 50i means 25 interlaced frames per second.

A frame or field rate can also be specified without a resolution. It can then usually be assumed to be either 50 or 60, except for 1080p which is only supported as 1080p24, 1080p25 or 1080p30 by consumer HDTV displays. Often the frame or field rate is left out. The format 1080i50 is 1920 × 1080 pixels, interlaced encoding with 50 fields (25 frames) per second.

For example, the format 720p60 is 1280 × 720 pixels, progressive encoding with 60 frames per second. In the context of HDTV, the formats of the broadcasts are referred to using a notation describing:. . This is a confusing use of the terms HD and HDTV.

Even HD-ready sets do not necessarily have enough pixels to display video to the 1080-line (1920x1080) or 720-line (1280x720) HD standards in full resolution without interpolation, and HD-compatible sets are often just standard-definition sets with an HDMI input. They indicate that a TV or display is able to accept video over an HDMI connection, using a new connector design, the main purpose of which seems to be to ensure that digital video is only passed over an interface which, by agreement, incorporates copyright protection. The terms HD ready and HD compatible are being used around the industrial world for marketing purposes. The world used analog PAL, NTSC, SECAM and other standards for over half a century.

Most patents were expiring by the end of World War II leaving the market wide open and no worldwide standard for television agreed upon. It was patent interference lawsuits and deployment issues given the tumultuous financial climate of the late 20's and 30's. Farnsworth, John Logie Baird and Vladimir Zworkin had each developed competing TV systems but resolution was not the issue that separated their substantially different technologies. Historically, the term high-definition television was also used to refer to television standards developed in the 1930s to replace the early experimental systems, although, not so long afterwards, Philo T.

Except for early analog formats in Europe and Japan, HDTV is broadcast digitally, and therefore its introduction sometimes coincides with the introduction of digital television (DTV). High-definition television (HDTV) means broadcast of television signals with a higher resolution than traditional formats (NTSC, SÉCAM, PAL) allow. TV Azteca Plans HDTV Mexican Rollout. High Definition (HD) Image Formats for Television Production, technical report from the EBU.

High Definition for Europe - a progressive approach, article from the EBU technical review . Images formats for HDTV, article from the EBU technical review . DVB HDTV standard. DTV channel protection ratios.

United States Federal Standard 1037C. MUSE had a bit-reduced stereo audio transmission system that was notable in its design as it was not psychoacoustical like Musicam. Considering the technological limitations of the time, MUSE was a very cleverly-designed analog system. Whole-camera pans would result in a loss of 50% of horizontal resolution.

Stationary images were transmitted at full resolution. Moving images were thus blurred in a manner similar to using 16mm movie film for HDTV projection. In the typical setup, three picture elements on a line were actually derived from three separate scans. The increased clarity, and detail make larger screen sizes more comfortable and pleasing to watch.

Both systems will usually play current DVDs, and attempt to extract a near-HDTV-quality image from them, but they are not compatible with each other. One is called HD DVD, the other is Blu-ray. Two new pre-recorded disc formats will be available in spring 2006. The gaps between scaning lines are smaller or gone.

The visual information is about 2-5 times more detailed overall. The colors will generally look more realistic, due to the cleaner signal. Most HD programming and films will be presented in the 16x9 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. You would never get a snowy, washed out, image, or vertical rolling.

All commercial HD is digital, so the signal will either deliver a good picture, a picture with large pixelation, a series of frozen pictures, or no picture. 60i (NTSC). 50i (PAL). 60p.

50p. 30p. 25p. 24p (cinematic film).

NTSC is typically 720x480. Number of frames or fields per second. Progressive frames (p) or interlaced fields (i). The number of lines in the display resolution.