1.
Fax
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Fax, sometimes called telecopying or telefax, is the telephonic transmission of scanned printed material, normally to a telephone number connected to a printer or other output device. The receiving fax machine interprets the tones and reconstructs the image, early systems used direct conversions of image darkness to audio tone in a continuous or analog manner. Since the 1980s, most machines modulate the audio frequencies using a digital representation of the page which is compressed to quickly transmit areas which are all-white or all-black. Scottish inventor Alexander Bain worked on chemical mechanical fax type devices and he received British patent 9745 on May 27,1843 for his Electric Printing Telegraph. Frederick Bakewell made several improvements on Bains design and demonstrated a telefax machine, the Pantelegraph was invented by the Italian physicist Giovanni Caselli. He introduced the first commercial service between Paris and Lyon in 1865, some 11 years before the invention of the telephone. In 1880, English inventor Shelford Bidwell constructed the scanning phototelegraph that was the first telefax machine to scan any two-dimensional original, previously, photographs had been sent over the radio using this process. The Western Union Deskfax fax machine, announced in 1948, was a machine that fit comfortably on a desktop. As a designer for the Radio Corporation of America, in 1924, Richard H. Ranger invented the wireless photoradiogram, or transoceanic radio facsimile, the forerunner of today’s fax machines. A photograph of President Calvin Coolidge sent from New York to London on November 29,1924 became the first photo picture reproduced by transoceanic radio facsimile, commercial use of Ranger’s product began two years later. Also in 1924, Herbert E. Ives of AT&T Corporation transmitted and reconstructed the first color facsimile, around 1952 or so, Finch Facsimile, a highly developed machine, was described in detail in a book, it was never manufactured in quantity. By the late 1940s, radiofax receivers were sufficiently miniaturized to be fitted beneath the dashboard of Western Unions Telecar telegram delivery vehicles, in the 1960s, the United States Army transmitted the first photograph via satellite facsimile to Puerto Rico from the Deal Test Site using the Courier satellite. Radio fax is still in limited use today for transmitting weather charts, in 1964, Xerox Corporation introduced what many consider to be the first commercialized version of the modern fax machine, under the name or Long Distance Xerography. This model was superseded two years later with a unit that would set the standard for fax machines for years to come. Up until this point facsimile machines were expensive and hard to operate. In 1966, Xerox released the Magnafax Telecopiers, a smaller and this unit was far easier to operate and could be connected to any standard telephone line. This machine was capable of transmitting a letter-sized document in about six minutes, the first sub-minute, digital fax machine was developed by Dacom, which built on digital data compression technology originally developed at Lockheed for satellite communication. By the late 1970s, many companies around the world, entered the fax market, very shortly after a new wave of more compact, faster and efficient fax machines would hit the market
2.
Intellectual property
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Intellectual property refers to creations of the intellect for which a monopoly is assigned to designated owners by law. Intellectual property rights are the protections granted to the creators of IP, and include trademarks, copyright, patents, industrial design rights, and in some jurisdictions trade secrets. Artistic works including music and literature, as well as discoveries, inventions, words, phrases, symbols, the Statute of Monopolies and the British Statute of Anne are seen as the origins of patent law and copyright respectively, firmly establishing the concept of intellectual property. The first known use of the intellectual property dates to 1769. The first clear example of modern usage goes back as early as 1808, the German equivalent was used with the founding of the North German Confederation whose constitution granted legislative power over the protection of intellectual property to the confederation. According to Lemley, it was only at point that the term really began to be used in the United States. The history of patents does not begin with inventions, but rather with royal grants by Queen Elizabeth I for monopoly privileges, the evolution of patents from royal prerogative to common-law doctrine. The term can be used in an October 1845 Massachusetts Circuit Court ruling in the patent case Davoll et al. v. Brown. The statement that discoveries are. property goes back earlier, in Europe, French author A. Nion mentioned propriété intellectuelle in his Droits civils des auteurs, artistes et inventeurs, published in 1846. Until recently, the purpose of property law was to give as little protection as possible in order to encourage innovation. Historically, therefore, they were granted only when they were necessary to encourage invention, limited in time, the concepts origins can potentially be traced back further. In 500 BCE, the government of the Greek state of Sybaris offered one years patent to all who should discover any new refinement in luxury. Intellectual property rights include patents, copyright, industrial design rights, trademarks, plant variety rights, trade dress, geographical indications, a copyright gives the creator of an original work exclusive rights to it, usually for a limited time. Copyright may apply to a range of creative, intellectual, or artistic forms. Copyright does not cover ideas and information themselves, only the form or manner in which they are expressed, an industrial design right protects the visual design of objects that are not purely utilitarian. An industrial design consists of the creation of a shape, configuration or composition of pattern or color, or combination of pattern, an industrial design can be a two- or three-dimensional pattern used to produce a product, industrial commodity or handicraft. Plant breeders rights or plant variety rights are the rights to use a new variety of a plant. The variety must amongst others be novel and distinct and for registration the evaluation of propagating material of the variety is examined, a trademark is a recognizable sign, design or expression which distinguishes products or services of a particular trader from the similar products or services of other traders
3.
Nokia
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Nokia Corporation, stylised as NOKIA, is a Finnish multinational communications and information technology company, founded in 1865. Nokia is headquartered in Espoo, Uusimaa, in the greater Helsinki metropolitan area, in 2014, Nokia employed 61,656 people across 120 countries, did business in more than 150 countries and reported annual revenues of around €12.73 billion. Nokia is a limited company listed on the Helsinki Stock Exchange. It is the worlds 274th-largest company measured by 2013 revenues according to the Fortune Global 500 and is a component of the Euro Stoxx 50 stock market index, the company has had various industries in its 151-year history. It was founded as a mill, and now focuses on large-scale telecommunications infrastructures. Nokias dominance also extended into the industry through its Symbian platform. Nokia eventually entered into a pact with Microsoft in 2011 to exclusively use Microsofts Windows Phone platform on future smartphones and its mobile phone business was eventually bought by Microsoft in an overall deal totaling $7.17 billion. Stephen Elop, Nokias former CEO, and several other joined the new Microsoft Mobile subsidiary of Microsoft as part of the deal. Nokia has a history, dating back to 1865 when Fredrik Idestam. A second pulp mill was created in 1868 near the town of Nokia, in 1871, Idestam together with friend Leo Mechelin formed a shared company and called it Nokia, after the town of the second pulp mill. For the next 90 years, Nokia on its own would be a forest and power industry company, in 1922, Nokia was jointly-owned with a trio partnership with Finnish Cable Works and Finnish Rubber Works. Nokia Corporation now boasted many industries including rubber, forestry, cable, electricity, in the 1970s, the newly formed conglomerate started entering the networking and radio industry. Nokia also started making military equipment for Finlands defence forces, such as the Sanomalaite M/90 communicator in 1983, in 1979, Nokia went into a joint venture with television maker Salora, to create Mobira, which would lay out the foundation of Nokias future mobile phone division. In 1981, Mobira launched the Nordic Mobile Telephone service, the worlds first international cellular network, then in 1982, Mobira launched the Mobira Senator car phone, which can be considered as Nokias first mobile phone. At that time, though, Nokia had no interest at all in mobile phones and it is only due to the Salo, Finland-based Salora-Mobira that the idea was pushed through. In 1987, Finnish Cable Works discontinued production of cables at its Helsinki factory, nokian Tyres, a tyre producer that was originally formed as a division of Finnish Rubber Works in 1932, split away from Nokia Corporation in 1988. Two years later in 1990, Finnish Rubber Works followed suit and this allowed Nokia Corporation to solely focus on communications. Jorma Ollila became CEO in 1992, Nokias first fully portable mobile phone was the Mobira Cityman 900 in 1987
4.
Multimedia
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Multimedia is content that uses a combination of different content forms such as text, audio, images, animations, video and interactive content. Multimedia contrasts with media that use only rudimentary computer displays such as text-only or traditional forms of printed or hand-produced material, Multimedia devices are electronic media devices used to store and experience multimedia content. Multimedia is distinguished from mixed media in art, for example. The term rich media is synonymous with interactive multimedia, the term multimedia was coined by singer and artist Bob Goldstein to promote the July 1966 opening of his LightWorks at LOursin show at Southampton, Long Island. Goldstein was perhaps aware of an American artist named Dick Higgins, two years later, in 1968, the term multimedia was re-appropriated to describe the work of a political consultant, David Sawyer, the husband of Iris Sawyer—one of Goldsteins producers at LOursin. In the intervening forty years, the word has taken on different meanings, in the late 1970s, the term referred to presentations consisting of multi-projector slide shows timed to an audio track. However, by the 1990s multimedia took on its current meaning, in the 1993 first edition of Multimedia, Making It Work, Tay Vaughan declared Multimedia is any combination of text, graphic art, sound, animation, and video that is delivered by computer. When you allow the user – the viewer of the project – to control what, when you provide a structure of linked elements through which the user can navigate, interactive multimedia becomes hypermedia. The German language society Gesellschaft für deutsche Sprache recognized the words significance, the institute summed up its rationale by stating has become a central word in the wonderful new media world. In common usage, multimedia refers to an electronically delivered combination of media including video, still images, audio, much of the content on the web today falls within this definition as understood by millions. That era saw also a boost in the production of educational multimedia CD-ROMs, the term video, if not used exclusively to describe motion photography, is ambiguous in multimedia terminology. Video is often used to describe the format, delivery format. Multiple forms of content are often not considered modern forms of presentation such as audio or video. Likewise, single forms of content with single methods of information processing are often called multimedia. Performing arts may also be considered multimedia considering that performers and props are multiple forms of content and media. Multimedia presentations may be viewed by person on stage, projected, transmitted, a broadcast may be a live or recorded multimedia presentation. Broadcasts and recordings can be analog or digital electronic media technology. Digital online multimedia may be downloaded or streamed, streaming multimedia may be live or on-demand
5.
Orange S.A.
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Orange S. A. formerly France Télécom S. A. is a French multinational telecommunications corporation. It has 256 million customers worldwide and employs 95,000 people in France, in 2015, the group had revenue of €40 billion. The companys head office is located in the 15th arrondissement of Paris, the current CEO is Stéphane Richard. The company is a component of the Euro Stoxx 50 stock market index, Orange has been the companys main brand for mobile, landline, internet and IPTV services since 2006. It originated in 1994 when Hutchison Whampoa acquired a stake in Microtel Communications during the early 1990s. It became a subsidiary of Mannesmann in 1999 and was acquired by France Télécom in 2000, the company was rebranded as Orange in July 2013. In 1792, under the French Revolution, the first communication network was developed to enable the rapid transmission of information in a warring and that was the optical telegraphy network of Claude Chappe. In 1878, after the invention of the telegraph and then the invention of the telephone. Telephone Services were added to the ministry when they were nationalised in 1889, however, it was not until 1923 that the second T appeared and the department of P&T became PTT. In 1941, a General Direction of Telecommunications was created within this ministry, then, in 1944, the National Centre of Telecommunications Studies was created to develop the telecommunications industry in France. In the 1970s, France tried extra hard to make up its delay on other countries with the programme delta LP and it was at the time when the majority of the local loop was built, that is all the cables linking the users to the operator. Moreover, with the help of French manufacturers, digital switching, the Minitel, until 1988, France Télécom was known as the Direction Générale des Télécommunications, a division of the Ministry of Posts and Telecommunications. This was in response to a European directive, aimed at making competition mandatory in public services from 1 January 1998, the 2 July 1990 Bill changed France Télécom into an operator of public law, with Marcel Roulet the first Chairman. Since then, the company has had a body corporate from the State. It was privatised by Lionel Jospins Plural Left government starting on 1 January 1998, the French government, both directly and through its holding company ERAP, continues to hold a stake of almost 27% in the company. In addition, the government Conseil of Ministers names the CEO, in 1982 Telecom introduced Minitel online ordering for its customers. In September 1995, Michel Bon was appointed to run France Télécom Group, in 1997, the capital of the new public company was successfully floated whereas the dot-com bubble phenomenon made the stock exchanges bullish. A second share offering occurred in 1998, Hutchison renamed Microtel to Orange Personal Communications Services Ltd, and on 28 April 1994 the Orange brand was launched in the UK mobile phone market
6.
DV
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DV is a format for storing digital video. It was launched in 1995 with joint efforts of leading producers of video camera recorders, the original DV specification, known as Blue Book, was standardized within the IEC61834 family of standards. These standards define common features such as physical videocassettes, recording modulation method, magnetization, part 2 describes the specifics of 525-60 and 625-50 systems. The IEC standards are available as publications sold by IEC and ANSI, in 2003, DV was joined by a successor format HDV, which used the same tape format with a different video codec. Some cameras at the time had the ability to switch between DV and HDV recording modes, DV uses lossy compression of video while audio is stored uncompressed. An intraframe video compression scheme is used to video on a frame-by-frame basis with the discrete cosine transform. Closely following ITU-R Rec.601 standard, DV video employs interlaced scanning with the sampling frequency of 13.5 MHz. This results in 480 scanlines per complete frame for the 60 Hz system, in both systems the active area contains 720 pixels per scanline, with 704 pixels used for content and 16 pixels on the sides left for digital blanking. The same frame size is used for 4,3 and 16,9 frame aspect ratios, prior to the DCT compression stage, chroma subsampling is applied to the source video in order to reduce the amount of data to be compressed. Baseline DV uses 4,1,1 subsampling in its 60 Hz variant and 4,2,0 subsampling in the 50 Hz variant. Audio can be stored in either of two forms, 16-bit Linear PCM stereo at 48 kHz sampling rate, or four nonlinear 12-bit PCM channels at 32 kHz sampling rate. In addition, the DV specification also supports 16-bit audio at 44.1 kHz, in practice, the 48 kHz stereo mode is used almost exclusively. The audio, video, and metadata are packaged into 80-byte Digital Interface Format blocks which are multiplexed into a 150-block sequence. DIF blocks are the units of DV streams and can be stored as computer files in raw form or wrapped in such file formats as Audio Video Interleave, QuickTime. One video frame is formed from either 10 or 12 such sequences, depending on scanning rate, which results in a rate of about 25 Mbit/s for video. When written to tape, each corresponds to one complete track. This means that the sound may be +/- ⅓ frame out of sync with the video, however, this is the maximum drift of the audio/video synchronization, it is not compounded throughout the recording. Sony and Panasonic created their versions of DV, which use the same compression scheme
7.
Dual-tone multi-frequency signaling
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DTMF was first developed in the Bell System in the United States, and became known under the trademark Touch-Tone for use in push-button telephones supplied to telephone customers, starting in 1963. DTMF is standardized by ITU-T Recommendation Q.23 and it is also known in the UK as MF4. The Touch-Tone system using a telephone keypad gradually replaced the use of dial and has become the industry standard for landline. Other multi-frequency systems are used for internal signaling within the telephone network, prior to the development of DTMF, telephone numbers were dialed by users with a loop-disconnect signaling, more commonly known as pulse dialing in the U. S. The exchange equipment responds to the dial pulses either directly by operating relays, the physical distance for which this type of dialing was possible was restricted by electrical distortions and was only possible on direct metallic links between end points of a line. Placing calls over longer distances required either operator assistance or provision of special subscriber trunk dialing equipment, operators used an earlier type of multi-frequency signaling. Multi-frequency signaling is a group of signaling methods that use a mixture of two pure tone sounds, various MF signaling protocols were devised by the Bell System and CCITT. This semi-automated signaling and switching proved successful in both speed and cost effectiveness, the DTMF system uses a set of eight audio frequencies transmitted in pairs to represent 16 signals, represented by the ten digits, the letters A to D, and the symbols # and *. AT&T described the product as a method for pushbutton signaling from customer stations using the transmission path. DTMF was known throughout the Bell System by the trademark Touch-Tone, the term was first used by AT&T in commerce on July 5,1960 and was introduced to the public on November 18,1963, when the first push-button telephone was made available to the public. It was a trademark by AT&T from September 4,1962 to March 13,1984. It is standardized by ITU-T Recommendation Q.23, in the UK, it is also known as MF4. Other vendors of compatible telephone equipment called the Touch-Tone feature tone dialing or DTMF, previously, terrestrial television stations used DTMF tones to control remote transmitters. The engineers had envisioned telephones being used to access computers, and they consulted with companies to determine the requirements. This led to the addition of the sign and asterisk or star keys as well as a group of keys for menu selection. Public payphones that accept credit cards use these codes to send the information from the magnetic strip. The AUTOVON telephone system of the United States Armed Forces used these signals to assert certain privilege, precedence is still a feature of military telephone networks, but using number combinations. For example, entering 93 before a number is a priority call, present-day uses of the A, B, C and D signals on telephone networks are few, and are exclusive to network control
8.
International Organization for Standardization
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The International Organization for Standardization is an international standard-setting body composed of representatives from various national standards organizations. Founded on 23 February 1947, the organization promotes worldwide proprietary and it is headquartered in Geneva, Switzerland, and as of March 2017 works in 162 countries. It was one of the first organizations granted general consultative status with the United Nations Economic, ISO, the International Organization for Standardization, is an independent, non-governmental organization, the members of which are the standards organizations of the 162 member countries. It is the worlds largest developer of international standards and facilitates world trade by providing common standards between nations. Nearly twenty thousand standards have been set covering everything from manufactured products and technology to food safety, use of the standards aids in the creation of products and services that are safe, reliable and of good quality. The standards help businesses increase productivity while minimizing errors and waste, by enabling products from different markets to be directly compared, they facilitate companies in entering new markets and assist in the development of global trade on a fair basis. The standards also serve to safeguard consumers and the end-users of products and services, the three official languages of the ISO are English, French, and Russian. The name of the organization in French is Organisation internationale de normalisation, according to the ISO, as its name in different languages would have different abbreviations, the organization adopted ISO as its abbreviated name in reference to the Greek word isos. However, during the meetings of the new organization, this Greek word was not invoked. Both the name ISO and the logo are registered trademarks, the organization today known as ISO began in 1926 as the International Federation of the National Standardizing Associations. ISO is an organization whose members are recognized authorities on standards. Members meet annually at a General Assembly to discuss ISOs strategic objectives, the organization is coordinated by a Central Secretariat based in Geneva. A Council with a membership of 20 member bodies provides guidance and governance. The Technical Management Board is responsible for over 250 technical committees, ISO has formed joint committees with the International Electrotechnical Commission to develop standards and terminology in the areas of electrical and electronic related technologies. Information technology ISO/IEC Joint Technical Committee 1 was created in 1987 to evelop, maintain, ISO has three membership categories, Member bodies are national bodies considered the most representative standards body in each country. These are the members of ISO that have voting rights. Correspondent members are countries that do not have their own standards organization and these members are informed about ISOs work, but do not participate in standards promulgation. Subscriber members are countries with small economies and they pay reduced membership fees, but can follow the development of standards
9.
Data compression
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In signal processing, data compression, source coding, or bit-rate reduction involves encoding information using fewer bits than the original representation. Compression can be lossy or lossless. Lossless compression reduces bits by identifying and eliminating statistical redundancy, no information is lost in lossless compression. Lossy compression reduces bits by removing unnecessary or less important information, the process of reducing the size of a data file is referred to as data compression. In the context of data transmission, it is called coding in opposition to channel coding. Compression is useful because it reduces resources required to store and transmit data, computational resources are consumed in the compression process and, usually, in the reversal of the process. Data compression is subject to a space–time complexity trade-off, Lossless data compression algorithms usually exploit statistical redundancy to represent data without losing any information, so that the process is reversible. Lossless compression is possible because most real-world data exhibits statistical redundancy, for example, an image may have areas of color that do not change over several pixels, instead of coding red pixel, red pixel. The data may be encoded as 279 red pixels and this is a basic example of run-length encoding, there are many schemes to reduce file size by eliminating redundancy. The Lempel–Ziv compression methods are among the most popular algorithms for lossless storage, DEFLATE is a variation on LZ optimized for decompression speed and compression ratio, but compression can be slow. DEFLATE is used in PKZIP, Gzip, and PNG, LZW is used in GIF images. LZ methods use a table-based compression model where table entries are substituted for repeated strings of data, for most LZ methods, this table is generated dynamically from earlier data in the input. The table itself is often Huffman encoded, current LZ-based coding schemes that perform well are Brotli and LZX. LZX is used in Microsofts CAB format, the best modern lossless compressors use probabilistic models, such as prediction by partial matching. The Burrows–Wheeler transform can also be viewed as a form of statistical modelling. The basic task of grammar-based codes is constructing a context-free grammar deriving a single string, sequitur and Re-Pair are practical grammar compression algorithms for which software is publicly available. In a further refinement of the use of probabilistic modelling. Arithmetic coding is a more modern coding technique that uses the mathematical calculations of a machine to produce a string of encoded bits from a series of input data symbols
10.
International Electrotechnical Commission
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The IEC also manages three global conformity assessment systems that certify whether equipment, system or components conform to its International Standards. The first International Electrical Congress took place in 1881 at the International Exposition of Electricity, at that time the International System of Electrical and Magnetic Units was agreed to. The IEC was instrumental in developing and distributing standards for units of measurement, particularly Gauss, Hertz and it also first proposed a system of standards, the Giorgi System, which ultimately became the SI, or Système International d’unités. In 1938, it published a multilingual international vocabulary to unify terminology relating to electrical, electronic and this effort continues, and the International Electrotechnical Vocabulary remains an important work in the electrical and electronic industries. The CISPR – in English, the International Special Committee on Radio Interference – is one of the groups founded by the IEC, originally located in London, the commission moved to its current headquarters in Geneva in 1948. It has regional centres in Asia-Pacific, Latin America and North America, today, the IEC is the worlds leading international organization in its field, and its standards are adopted as national standards by its members. The work is done by some 10,000 electrical and electronics experts from industry, government, academia, test labs, IEC standards have numbers in the range 60000–79999 and their titles take a form such as IEC60417, Graphical symbols for use on equipment. Following the Dresden Agreement with CENELEC the numbers of older IEC standards were converted in 1997 by adding 60000, for example IEC27 became IEC60027. Standards of the 60000 series are also preceded by EN to indicate that the IEC standard is also adopted by CENELEC as a European standard. The IEC cooperates closely with the International Organization for Standardization and the International Telecommunication Union, Standards developed jointly with ISO such as ISO/IEC26300, ISO/IEC27001, and CASCO ISO/IEC17000 series, carry the acronym of both organizations. The use of the ISO/IEC prefix covers publications from ISO/IEC Joint Technical Committee 1 - Information Technology, as well as conformity assessment standards developed by ISO CASCO, other standards developed in cooperation between IEC and ISO are assigned numbers in the 80000 series, such as IEC 82045-1. IEC standards are also being adopted by other certifying bodies such as BSI, CSA, UL & ANSI/INCITS, SABS, SAI, SPC/GB, IEC standards adopted by other certifying bodies may have some noted differences from the original IEC standard. The IEC is made up of members, called national committees, national committees are constituted in different ways. Some NCs are public sector only, some are a combination of public and private sector, about 90% of those who prepare IEC standards work in industry
11.
MPEG-1
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MPEG-1 is a standard for lossy compression of video and audio. Today, MPEG-1 has become the most widely compatible lossy audio/video format in the world, perhaps the best-known part of the MPEG-1 standard is the MP3 audio format it introduced. The MPEG-1 standard is published as ISO/IEC11172 – Information technology—Coding of moving pictures, MPEG was formed to address the need for standard video and audio formats, and to build on H.261 to get better quality through the use of more complex encoding methods. Development of the MPEG-1 standard began in May 1988, fourteen video and fourteen audio codec proposals were submitted by individual companies and institutions for evaluation. The codecs were extensively tested for computational complexity and subjective quality and this specific bitrate was chosen for transmission over T-1/E-1 lines and as the approximate data rate of audio CDs. The codecs that excelled in testing were utilized as the basis for the standard and refined further, with additional features. The reported completion date of the MPEG-1 standard varies greatly, a complete draft standard was produced in September 1990. The draft standard was publicly available for purchase, the standard was finished with the 6 November 1992 meeting. The Berkeley Plateau Multimedia Research Group developed an MPEG-1 decoder in November 1992, due in part to the similarity between the two codecs, the MPEG-2 standard includes full backwards compatibility with MPEG-1 video, so any MPEG-2 decoder can play MPEG-1 videos. This means that MPEG-1 coding efficiency can vary depending on the encoder used. The first three parts of ISO/IEC11172 were published in August 1993, the ISO patent database lists one patent for ISO11172, US4,472,747, which expired in 2003. The near-complete draft of the MPEG-1 standard was publicly available as ISO CD11172 by December 6,1991, a May 2009 discussion on the whatwg mailing list mentioned US5,214,678 patent as possibly covering MPEG audio layer II. Filed in 1990 and published in 1993, this patent is now expired, most popular software for video playback includes MPEG-1 decoding, in addition to any other supported formats. The popularity of MP3 audio has established a massive installed base of hardware that can play back MPEG-1 Audio, virtually all digital audio devices can play back MPEG-1 Audio. Many millions have been sold to-date, before MPEG-2 became widespread, many digital satellite/cable TV services used MPEG-1 exclusively. The widespread popularity of MPEG-2 with broadcasters means MPEG-1 is playable by most digital cable and satellite set-top boxes, MPEG-1 was used for full-screen video on Green Book CD-i, and on Video CD. The Super Video CD standard, based on VCD, uses MPEG-1 audio exclusively, the DVD-Video format uses MPEG-2 video primarily, but MPEG-1 support is explicitly defined in the standard. The DVD-Video standard originally required MPEG-1 Layer II audio for PAL countries, MPEG-1 Layer II audio is still allowed on DVDs, although newer extensions to the format, like MPEG Multichannel, are rarely supported
