1080i is an abbreviation referring to a combination of frame resolution and scan type, used in high-definition television and high-definition video. The number "1080" refers to the number of horizontal lines on the screen; the "i" is an abbreviation for "interlaced". A related display resolution is 1080p, which has 1080 lines of resolution; the term assumes a widescreen aspect ratio of 16:9, so the 1080 lines of vertical resolution implies 1920 columns of horizontal resolution, or 1920 pixels × 1080 lines. A 1920 pixels × 1080 lines screen has a total of 2.1 megapixels and a temporal resolution of 50 or 60 interlaced fields per second. This format is used in the SMPTE 292M standard; the choice of 1080 lines originates with Charles Poynton, who in the early 1990s pushed for "square pixels" to be used in HD video formats. Within the designation "1080i", the i stands for interlaced scan. A frame of 1080i video consists of two sequential fields of 540 vertical pixels; the first field consists of all odd-numbered TV lines and the second all numbered lines.
The horizontal lines of pixels in each field are captured and displayed with a one-line vertical gap between them, so the lines of the next field can be interlaced between them, resulting in 1080 total lines. 1080i differs from 1080p, where the p stands for progressive scan, where all lines in a frame are captured at the same time. In native or pure 1080i, the two fields of a frame correspond to different instants, so motion portrayal is good; this is true for interlaced video in general and can be observed in still images taken of fast motion scenes. However, when 1080p material is captured at 25 or 30 frames/second, it is converted to 1080i at 50 or 60 fields/second for processing or broadcasting. In this situation both fields in a frame do correspond to the same instant; the field-to-instant relation is somewhat more complex for the case of 1080p at 24 frames/second converted to 1080i at 60 fields/second. The field rate of 1080i is 60 Hz for countries that use or used System M as analog television system with 60 fields/sec, or 50 Hz for regions that use or used 625-lines television system with 50 fields/sec.
Both field rates can be carried by major digital television broadcast formats such as ATSC, DVB, ISDB-T International. The frame rate can be implied by the context, while the field rate is specified after the letter i, such as "1080i60". In this case 1080i60 refers to 60 fields per second; the European Broadcasting Union prefers to use the resolution and frame rate separated by a slash, as in 1080i/30 and 1080i/25 480i/30 and 576i/25. Resolutions of 1080i60 or 1080i50 refers to 1080i/30 or 1080i/25 in EBU notation. 1080i is directly compatible with some CRT HDTVs on which it can be displayed natively in interlaced form, but for display on progressive-scan—e.g. Most new LCD and plasma TVs, it must be deinterlaced. Depending on the television's video processing capabilities, the resulting video quality may vary, but may not suffer. For example, film material at 25fps may be deinterlaced from 1080i50 to restore a full 1080p resolution at the original frame rate without any loss. Preferably video material with 50 or 60 motion phases/second is to be converted to 50p or 60p before display.
Worldwide, most HD channels on satellite and cable broadcast in 1080i. In the United States, 1080i is the preferred format for most broadcasters, with Inc.. Viacom, AT&T, Comcast owned networks broadcasting in the format. Only Fox-owned television networks and Disney-owned television networks, along with MLB Network and a few other cable networks use 720p as the preferred format for their networks. Many ABC affiliates owned by Hearst Television and former Belo Corporation stations owned by TEGNA, along with some individual affiliates of those three networks, air their signals in 1080i and upscale network programming for master control and transmission purposes, as most syndicated programming and advertising is produced and distributed in 1080i, removing a downscaling step to 720p; this allows local newscasts on these ABC affiliates to be produced in the higher resolution to match the picture quality of their 1080i competitors. Some cameras and broadcast systems that use 1080 vertical lines per frame do not use the full 1920 pixels of a nominal 1080i picture for image capture and encoding.
Common subsampling ratios include 3/4 and 1/2. Where used, the lower horizontal resolution is scaled to capture and/or display a full-sized picture. Using half horizontal resolution and only one field of each frame results in the format known as qHD, which has fram
Canada is a country in the northern part of North America. Its ten provinces and three territories extend from the Atlantic to the Pacific and northward into the Arctic Ocean, covering 9.98 million square kilometres, making it the world's second-largest country by total area. Canada's southern border with the United States is the world's longest bi-national land border, its capital is Ottawa, its three largest metropolitan areas are Toronto and Vancouver. As a whole, Canada is sparsely populated, the majority of its land area being dominated by forest and tundra, its population is urbanized, with over 80 percent of its inhabitants concentrated in large and medium-sized cities, many near the southern border. Canada's climate varies across its vast area, ranging from arctic weather in the north, to hot summers in the southern regions, with four distinct seasons. Various indigenous peoples have inhabited what is now Canada for thousands of years prior to European colonization. Beginning in the 16th century and French expeditions explored, settled, along the Atlantic coast.
As a consequence of various armed conflicts, France ceded nearly all of its colonies in North America in 1763. In 1867, with the union of three British North American colonies through Confederation, Canada was formed as a federal dominion of four provinces; this began an accretion of provinces and territories and a process of increasing autonomy from the United Kingdom. This widening autonomy was highlighted by the Statute of Westminster of 1931 and culminated in the Canada Act of 1982, which severed the vestiges of legal dependence on the British parliament. Canada is a parliamentary democracy and a constitutional monarchy in the Westminster tradition, with Elizabeth II as its queen and a prime minister who serves as the chair of the federal cabinet and head of government; the country is a realm within the Commonwealth of Nations, a member of the Francophonie and bilingual at the federal level. It ranks among the highest in international measurements of government transparency, civil liberties, quality of life, economic freedom, education.
It is one of the world's most ethnically diverse and multicultural nations, the product of large-scale immigration from many other countries. Canada's long and complex relationship with the United States has had a significant impact on its economy and culture. A developed country, Canada has the sixteenth-highest nominal per capita income globally as well as the twelfth-highest ranking in the Human Development Index, its advanced economy is the tenth-largest in the world, relying chiefly upon its abundant natural resources and well-developed international trade networks. Canada is part of several major international and intergovernmental institutions or groupings including the United Nations, the North Atlantic Treaty Organization, the G7, the Group of Ten, the G20, the North American Free Trade Agreement and the Asia-Pacific Economic Cooperation forum. While a variety of theories have been postulated for the etymological origins of Canada, the name is now accepted as coming from the St. Lawrence Iroquoian word kanata, meaning "village" or "settlement".
In 1535, indigenous inhabitants of the present-day Quebec City region used the word to direct French explorer Jacques Cartier to the village of Stadacona. Cartier used the word Canada to refer not only to that particular village but to the entire area subject to Donnacona. From the 16th to the early 18th century "Canada" referred to the part of New France that lay along the Saint Lawrence River. In 1791, the area became two British colonies called Upper Canada and Lower Canada collectively named the Canadas. Upon Confederation in 1867, Canada was adopted as the legal name for the new country at the London Conference, the word Dominion was conferred as the country's title. By the 1950s, the term Dominion of Canada was no longer used by the United Kingdom, which considered Canada a "Realm of the Commonwealth"; the government of Louis St. Laurent ended the practice of using'Dominion' in the Statutes of Canada in 1951. In 1982, the passage of the Canada Act, bringing the Constitution of Canada under Canadian control, referred only to Canada, that year the name of the national holiday was changed from Dominion Day to Canada Day.
The term Dominion was used to distinguish the federal government from the provinces, though after the Second World War the term federal had replaced dominion. Indigenous peoples in present-day Canada include the First Nations, Métis, the last being a mixed-blood people who originated in the mid-17th century when First Nations and Inuit people married European settlers; the term "Aboriginal" as a collective noun is a specific term of art used in some legal documents, including the Constitution Act 1982. The first inhabitants of North America are hypothesized to have migrated from Siberia by way of the Bering land bridge and arrived at least 14,000 years ago; the Paleo-Indian archeological sites at Old Crow Flats and Bluefish Caves are two of the oldest sites of human habitation in Canada. The characteristics of Canadian indigenous societies included permanent settlements, complex societal hierarchies, trading networks; some of these cultures had collapsed by the time European explorers arrived in the late 15th and early 16th centuries and have only been discovered through archeological investigations.
The indigenous population at the time of the first European settlements is estimated to have been between 200,000
Digital television transition
The digital television transition called the digital switchover, the analog switch-off, or the analog shutdown, is the process begun in 2006, in which older analog television broadcasting technology is converted to and replaced by digital television. Conducted by individual nations on different schedules, this involves the conversion of analog terrestrial television to digital terrestrial. However, it involves analog cable conversion to digital cable or internet protocol television, as well as analog to digital satellite television. Terrestrial transition was begun by some countries around 2000. By contrast, satellite transition was well underway or completed in many counties by this time, it is an involved process because the existing analog television receivers owned by viewers cannot receive digital broadcasts. In many countries, a simulcast service is operated where a broadcast is made available to viewers in both analog and digital at the same time; as digital becomes more popular, it is expected.
In most places this has happened, where a broadcaster has offered incentives to viewers to encourage them to switch to digital. In other cases government policies have been introduced to encourage or force the switchover process with regard to terrestrial broadcasts. Government intervention involves providing some funding for broadcasters and, in some cases, monetary relief to viewers, to enable a switchover to happen by a given deadline. Governments can require all receiving equipment sold in a country to support the necessary digital reception'tuner'; the switchover process is being accomplished on different schedules in different countries. In others, the whole country switches on one date, such as the Netherlands, which switched off its analog terrestrial services on 11 December 2006. On 3 August 2003, Berlin became the world's first city to switch off terrestrial analog signals. Luxembourg was the first country to complete its terrestrial switchover, in September 2006. 2001: United Kingdom/Republic of Ireland 2002: Faroe Islands 2006: Luxembourg, Netherlands 2007: Andorra, Sweden, Switzerland 2008: Germany 2009: Denmark, Isle of Man, United States 2010: Belgium, Estonia, Jersey, Latvia, San Marino, Spain, United Kingdom 2011: Austria, Cyprus, Israel, Malta, Turkey, United Kingdom 2012: Czech Republic, Republic of Ireland, Japan, Saudi Arabia, United Arab Emirates, Bahrain, Slovakia, South Korea, United Kingdom 2013: Australia, Bulgaria, North Macedonia, New Zealand, Poland 2014: Serbia, Namibia, Algeria 2015: Belarus, Greece, Morocco, Moldova, Rwanda, Kenya, Ghana, Georgia 2016: Bermuda, Mongolia, Chile, Burundi 2017: Brazil, Sri Lanka Romania Germany Unitymedia 2018: Brazil, Thailand, Uzbekistan 2019: Russia, Singapore, Moldova, Sri Lanka, Costa Rica 2020: Brazil, Morocco, Hong Kong, Thailand, Venezuela, Sudan, Côte d’Ivoire 2021: Dominican Republic, United States, Colombia, Argentina 2022: Canada, El Salvador 2023: Cuba, India, Peru 2023->: Vietnam Unknown: Iran, South Africa, Uruguay The Geneva 2006 Agreement set 17 June 2015 as the date after which countries may use frequencies assigned for analog television transmission for digital services, without being required to protect the analog services of neighbouring countries against interference.
This date was viewed as an internationally mandated analog switch-off date, at least along national borders. The European Commission has recommended that digital switchover should be completed by 1 January 2012 - Commission Recommendation 2009/848/EC, of 28 October 2009. Satellite broadcasting switched to digital much earlier than terrestrial broadcasting; the switchover process is much easier for satellite since only changes to the earth station equipment are needed on the transmission side and consumers are used to having a set top box/decoder. In many places, the satellite switchover was complete before terrestrial switchover was started. Cable on the other hand would switch off months, if not years. Algeria: Digital broadcasting started in 2009, analog signals were switched off on 10 November 2014. Gabon had turned off all analog signals on 17 June 2016. Ghana: Analog switch-off occurre
South Korea the Republic of Korea, is a country in East Asia, constituting the southern part of the Korean Peninsula and lying to the east of the Asian mainland. The name Korea is derived from Goguryeo, one of the great powers in East Asia during its time, ruling most of the Korean Peninsula, parts of the Russian Far East and Inner Mongolia, under Gwanggaeto the Great. South Korea has a predominantly mountainous terrain, it comprises an estimated 51.4 million residents distributed over 100,363 km2. Its capital and largest city is Seoul, with a population of around 10 million. Archaeology indicates that the Korean Peninsula was inhabited by early humans starting from the Lower Paleolithic period; the history of Korea begins with the foundation of Gojoseon in 2333 BCE by the mythic king Dangun, but no archaeological evidence and writing was found from this period. The Gija Joseon was purportedly founded in 11th century BCE, its existence and role has been controversial in the modern era; the written historical record on Gojoseon was first mentioned in Chinese records in the early 7th century BCE.
Following the unification of the Three Kingdoms of Korea under Unified Silla in CE 668, Korea was subsequently ruled by the Goryeo dynasty and the Joseon dynasty. It was annexed by the Empire of Japan in 1910. At the end of World War II, Korea was divided into Soviet and U. S. zones of occupations. A separate election was held in the U. S. zone in 1948 which led to the creation of the Republic of Korea, while the Democratic People's Republic of Korea was established in the Soviet zone. The United Nations at the time passed a resolution declaring the ROK to be the only lawful government in Korea; the Korean War began in June 1950. The war lasted three years and involved the U. S. China, the Soviet Union and several other nations; the border between the two nations remains the most fortified in the world. Under long-time military leader Park Chung-hee, the South Korean economy grew and the country was transformed into a G-20 major economy. Military rule ended in 1987, the country is now a presidential republic consisting of 17 administrative divisions.
South Korea is a developed country and a high-income economy, with a "very high" Human Development Index, ranking 22nd in the world. The country is considered a regional power and is the world's 11th largest economy by nominal GDP and the 12th largest by PPP as of 2010. South Korea is a global leader in the industrial and technological sectors, being the world's 5th largest exporter and 8th largest importer, its export-driven economy focuses production on electronics, ships, machinery and robotics. South Korea is a member of the ASEAN Plus mechanism, the United Nations, Uniting for Consensus, G20, the WTO and OECD and is a founding member of APEC and the East Asia Summit; the name Korea derives from the name Goryeo. The name Goryeo itself was first used by the ancient kingdom of Goguryeo in the 5th century as a shortened form of its name; the 10th-century kingdom of Goryeo succeeded Goguryeo, thus inherited its name, pronounced by the visiting Persian merchants as "Korea". The modern spelling of Korea first appeared in the late 17th century in the travel writings of the Dutch East India Company's Hendrick Hamel.
Despite the coexistence of the spellings Corea and Korea in 19th century publications, some Koreans believe that Imperial Japan, around the time of the Japanese occupation, intentionally standardised the spelling on Korea, making Japan appear first alphabetically. After Goryeo was replaced by Joseon in 1392, Joseon became the official name for the entire territory, though it was not universally accepted; the new official name has its origin in the ancient country of Gojoseon. In 1897, the Joseon dynasty changed the official name of the country from Joseon to Daehan Jeguk; the name Daehan, which means "Great Han" derives from Samhan, referring to the Three Kingdoms of Korea, not the ancient confederacies in the southern Korean Peninsula. However, the name Joseon was still used by Koreans to refer to their country, though it was no longer the official name. Under Japanese rule, the two names Han and Joseon coexisted. There were several groups who fought for independence, the most notable being the Provisional Government of the Republic of Korea.
Following the surrender of Japan, in 1945, the Republic of Korea was adopted as the legal English name for the new country. Since the government only controlled the southern part of the Korean Peninsula, the informal term South Korea was coined, becoming common in the Western world. While South Koreans use Han to refer to the entire country, North Koreans and ethnic Koreans living in China and Japan use the term Joseon as the name of the country; the Korean name "Daehan Minguk" is sometimes used by South Koreans as a metonym to refer to the Korean ethnicity as a whole, rather than just the South Korean state. The history of Korea begins with the founding of Joseon in 2333 BCE by Dangun, according to Korea's foundation mythology. Gojoseon expanded until it controlled parts of Manchuria. Gija Joseon was purportedly founded in the 12th century BC, but its existence and role have been controversial in the modern era. In 108 BCE, the Han dynasty defeated Wiman Joseon and installed four commanderies in the n
Honduras the Republic of Honduras, is a country in Central America. In the past, it was sometimes referred to as "Spanish Honduras" to differentiate it from British Honduras, which became modern-day Belize; the republic of Honduras is bordered to the west by Guatemala, to the southwest by El Salvador, to the southeast by Nicaragua, to the south by the Pacific Ocean at the Gulf of Fonseca, to the north by the Gulf of Honduras, a large inlet of the Caribbean Sea. Honduras was home to several important Mesoamerican cultures, most notably the Maya, before the Spanish invaded in the sixteenth century; the Spanish introduced Roman Catholicism and the now predominant Spanish language, along with numerous customs that have blended with the indigenous culture. Honduras became independent in 1821 and has since been a republic, although it has endured much social strife and political instability, remains one of the poorest countries in the Western Hemisphere. In 1960, the northern part of what was the Mosquito Coast was transferred from Nicaragua to Honduras by the International Court of Justice.
The nation's economy is agricultural, making it vulnerable to natural disasters such as Hurricane Mitch in 1998. The lower class is agriculturally based while wealth is concentrated in the country's urban centers. Honduras has a Human Development Index of 0.625, classifying it as a nation with medium development. When the Index is adjusted for income inequality, its Inequality-adjusted Human Development Index is 0.443. Honduran society is predominantly Mestizo; the nation had a high political stability until its 2009 coup and again with the 2017 presidential election. Honduras has high levels of sexual violence. Honduras has a population exceeding 9 million, its northern portions are part of the Western Caribbean Zone, as reflected in the area's demographics and culture. Honduras is known for its rich natural resources, including minerals, tropical fruit, sugar cane, as well as for its growing textiles industry, which serves the international market; the literal meaning of the term "Honduras" is "depths" in Spanish.
The name could either refer to the bay of Trujillo as an anchorage, fondura in the Leonese dialect of Spanish, or to Columbus's alleged quote that "Gracias a Dios que hemos salido de esas Honduras". It was not until the end of the 16th century. Prior to 1580, Honduras referred to only the eastern part of the province, Higueras referred to the western part. Another early name is Guaymuras, revived as the name for the political dialogue in 2009 that took place in Honduras as opposed to Costa Rica. Hondurans are referred to as Catracho or Catracha in Spanish; the word was coined by Nicaraguans and derives from the last name of the Spanish Honduran General Florencio Xatruch, who in 1857 led Honduran armed forces against an attempted invasion by North American adventurer William Walker. The nickname is considered not derogatory. In pre-Columbian times, modern Honduras was part of the Mesoamerican cultural area. In the west, Mayan civilization flourished for hundreds of years; the dominant state within Honduras' borders was in Copán.
Copán fell with the other Lowland centres during the conflagrations of the Terminal Classic in the 9th century. The Maya of this civilization survive in western Honduras as the Ch'orti', isolated from their Choltian linguistic peers to the west. Remnants of other Pre-Columbian cultures are found throughout the country. Archaeologists have studied sites such as Naco and La Sierra in the Naco Valley, Los Naranjos on Lake Yojoa, Yarumela in the Comayagua Valley, La Ceiba and Salitron Viejo, Selin Farm and Cuyamel in the Aguan valley, Cerro Palenque, Curruste, Despoloncal in the lower Ulua river valley, many others. On his fourth and the final voyage to the New World in 1502, Christopher Columbus landed near the modern town of Trujillo, near Guaimoreto Lagoon, becoming the first European to visit the Bay Islands on the coast of Honduras. On 30 July 1502, Columbus sent his brother Bartholomew to explore the islands and Bartholomew encountered a Mayan trading vessel from Yucatán, carrying well-dressed Maya and a rich cargo.
Bartholomew's men stole the cargo they wanted and kidnapped the ship's elderly captain to serve as an interpreter in the first recorded encounter between the Spanish and the Maya. In March 1524, Gil González Dávila became the first Spaniard to enter Honduras as a conquistador. Followed by Hernán Cortés, who had brought forces down from Mexico. Much of the conquest took place in the following two decades, first by groups loyal to Cristóbal de Olid, by those loyal to Francisco de Montejo but most by those following Alvarado. In addition to Spanish resources, the conquerors relied on armed forces from Mexico—Tlaxcalans and Mexica armies of thousands who remained garrisoned in the region. Resistance to conquest was led in particular by Lempira. Many regions in the north of Honduras never fell to the Spanish, notably the Miskito Kingdom. After the Spanish conquest, Honduras became part of Spain's vast empire in the New World within the Kingdom of Guatemala. Trujillo and Gracias were the first city-capitals.
The Spanish ruled the region for three centuries. Honduras was organized as a province of the Kingdom of Guatemala and the capital was fixed, first at Trujillo on the Atlantic coast, at Comayagua, final
Digital video recorder
A digital video recorder is an electronic device that records video in a digital format to a disk drive, USB flash drive, SD memory card, SSD or other local or networked mass storage device. The term includes set-top boxes with direct to disk recording, portable media players and TV gateways with recording capability, digital camcorders. Personal computers are connected to video capture devices and used as DVRs. Many DVRs are classified as consumer electronic devices. Consumer digital video recorders ReplayTV and TiVo were launched at the 1999 Consumer Electronics Show in Las Vegas, Nevada. Microsoft demonstrated a unit with DVR capability, but this did not become available until the end of 1999 for full DVR features in Dish Network's DISHplayer receivers. TiVo shipped their first units on March 31, 1999. ReplayTV won the "Best of Show" award in the video category with Netscape co-founder Marc Andreessen as an early investor and board member, but TiVo was more successful commercially. Legal action by media companies forced ReplayTV to remove many features such as automatic commercial skip and the sharing of recordings over the Internet, but newer devices have regained these functions while adding complementary abilities, such as recording onto DVDs and programming and remote control facilities using PDAs, networked PCs, Web browsers.
In contrast to VCRs, hard-disk based digital video recorders make "time shifting" more convenient and allow for functions such as pausing live TV, instant replay, chasing playback and skipping over advertising during playback. Many DVRs use the MPEG format for compressing the digital video. Video recording capabilities have become an essential part of the modern set-top box, as TV viewers have wanted to take control of their viewing experiences; as consumers have been able to converge increasing amounts of video content on their set-tops, delivered by traditional'broadcast' cable and terrestrial as well as IP networks, the ability to capture programming and view it whenever they want has become a must-have function for many consumers. At the 1999 CES, Dish Network demonstrated the hardware that would have DVR capability with the assistance of Microsoft software. Which included WebTV Networks internet TV. By the end of 1999 the Dishplayer had full DVR capabilities and within a year, over 200,000 units were sold.
In the UK, digital video recorders are referred to as "plus boxes". Freeview+ have been around in the UK since the late 2000s. British Sky Broadcasting markets a popular combined receiver and DVR as Sky+. TiVo launched a UK model in 2000, is no longer supported, except for third party services, the continuation of TiVo through Virgin Media in 2010. South African based Africa Satellite TV beamer Multichoice launched their DVR, available on their DStv platform. In addition to ReplayTV and TiVo, there are a number of other suppliers of digital terrestrial DVRs, including Thomson, Fusion, Pace Micro Technology, Humax, VBox Communications, AC Ryan Playon and Advanced Digital Broadcast. Many satellite, cable and IPTV companies are incorporating digital video recording functions into their set-top box, such as with DirecTiVo, DISHPlayer/DishDVR, Scientific Atlanta Explorer 8xxx from Time Warner, Total Home DVR from AT&T U-verse, Motorola DCT6412 from Comcast and others, Moxi Media Center by Digeo, or Sky+.
Astro introduced their DVR system, called Astro MAX, the first PVR in Malaysia but was phased out two years after its introduction. In the case of digital television, there is no encoding necessary in the DVR since the signal is a digitally encoded MPEG stream; the digital video recorder stores the digital stream directly to disk. Having the broadcaster involved with, sometimes subsidizing, the design of the DVR can lead to features such as the ability to use interactive TV on recorded shows, pre-loading of programs, or directly recording encrypted digital streams, it can, however force the manufacturer to implement non-skippable advertisements and automatically expiring recordings. In the United States, the FCC has ruled that starting on July 1, 2007, consumers will be able to purchase a set-top box from a third-party company, rather than being forced to purchase or rent the set-top box from their cable company; this ruling only applies to "navigation devices," otherwise known as a cable television set-top box, not to the security functions that control the user's access to the content of the cable operator.
The overall net effect on digital video recorders and related technology is unlikely to be substantial as standalone DVRs are readily available on the open market. In Europe Free-To-Air and Pay TV TV gateways with multiple tuners have whole house recording capabilities allowing recording of TV programs to Network Attached Storage or attached USB storage, recorded programs are shared across the home network to tablet, smartphone, PC, Smart TV. In 2003 many Satellite and Cable providers introduced dual-tuner digital video recorders. In the UK, BSkyB introduced their first PVR Sky+ with dual tuner support in 2001; these machines have two independent tuners within the same receiver. The main use for this feature is the capability to record a live program while watching another live program or
A DVD recorder is an optical disc recorder that uses optical disc recording technologies to digitally record analog or digital signals onto blank writable DVD media. Such devices are available as either installable drives for computers or as standalone components for use in television studios or home theater systems; as of March 1, 2007 all new tuner-equipped television devices manufactured or imported in the United States must include an ATSC tuner. The US Federal Communications Commission has interpreted this rule broadly, including apparatus such as computers with TV tuner cards with video capture ability, videocassette recorders and standalone DVD recorders. NTSC DVD recorders are undergoing a transformation, either adding a digital ATSC tuner or removing over-the-air broadcast television tuner capability entirely. However, these DVD recorders can still record analog video. Standalone DVD recorders have been scarce in the United States due to "restrictions on video recording." DVD recorders supported one of three standards: DVD-RAM, DVD-RW, DVD+RW, none of which are directly compatible.
Most current DVD drives support both the + and - standards, while few support the DVD-RAM standard, not directly compatible with standard DVD drives. Recording speed is denoted in values of X, where 1X in DVD usage is equal to 1.321 MB/s equivalent to a 9X CD-ROM. In practice, this is confined to computer-based DVD recorders, since standalone units record in real time, that is, 1X speed. Recorders use a laser to write DVDs; the reading laser is not stronger than 5 mW, while the writing laser is more powerful. The faster the writing speed is rated, the stronger the laser. DVD burner lasers peak at about 100-400 mW in continuous wave. DVD recorder drives are standard equipment in many computer systems on the market, after being popularized by the Pioneer/Apple SuperDrive. DVD recorder drives can be used in conjunction with DVD authoring software to create DVDs near or equal to commercial quality, are widely used for data backup and exchange; as a general rule, computer-based DVD recorders can handle CD-R and CD-RW media.
More manufacturers have begun to phase out DVD drives from laptop computers in favor of portability and digital media. Most internal drives are designed with SATA interfaces, with parallel ATA becoming rare. External drives use the USB standard for connectivity. DVD recorder drives manufactured since January 2000 are required by the DVD consortium to respect DVD region codes when reading a disc; the drives are incapable of assigning region codes when writing a disc as this is stored on a part of the disc to which PC based and standalone video recorders do not have write access. DVD duplication systems are built out of stacks of drives, connected through a computer-based backplane; when the standalone DVD recorder first appeared on the Japanese consumer market in 1999, early units were expensive, costing between $2500 and $4000 USD. More DVD recorders from notable brands have dropped in price. Early units supported only DVD-RAM and DVD-R discs, but newer units can record to DVD-R, DVD-RW, DVD+R, DVD+RW, DVD-R DL and DVD+R DL.
Certain models include mechanical hard disk drive-based digital video recorders to improve ease of use. Standalone DVD recorders have basic DVD authoring software built in. In 2009, Panasonic introduced the world's first Blu-ray disc recorder, capable of recording both DVDs and Blu-ray discs and featured built in satellite HDTV tuners. A year Panasonic introduced Blu-ray disc recorders with terrestrial HDTV tuners. DVD recorders have technical advantages over VCRs, including: Superior video and audio quality Easy-to-handle smaller form-factor disc media, higher durability compared to magnetic tape Random access to video chapters without rewinding or fast-forwarding Onscreen multilingual subtitles and labeling not available on VCRs Reduced playback wear and tear High-quality digital copying, with little or no generational quality loss Improved editing on rewritable media Playlisting No risk of accidentally recording over existing content or unexpectedly running out of space during recording Easily accessible recordings as a result of chapter menusNote: Blu-ray disc recorders can record full high definition videos on BD-Rs and BD-REs.
Disadvantages include: Slow initial access/load times due to the optical nature of the disc Limited rewritability on DVD-RW/+RW discs. DVD-RAM is better suited for high frequency re-recording Relatively short life of the laser diodes. In addition, DVDs recorded with DVD recorders in the standard DVD format must be finalized to view in other DVD players; this disadvantage does not apply to discs recorded in the newer and more flexible DVD-VR format or the DVD+VR format - the latter being compatible with DVD players. The implementation of MPEG-2 compression used on most standalone DVD recorders is required to compress the picture data in real time, producing results that may not be up to par with professionally rendered DVD video, which can take days to compress. Standard definition VCR replacement DVD video recorders has a set of standard recording modes for fitting 1, 2, 4, 6, 8, 10 hour modes on single layer 12cm discs; these modes are comparable to those found on VHS VCRs usin