Internet Protocol television is the delivery of television content over Internet Protocol networks. This is in contrast to delivery through traditional terrestrial and cable television formats. Unlike downloaded media, IPTV offers the ability to stream the source media continuously; as a result, a client media player can begin playing the content immediately. This is known as streaming media. Although IPTV uses the Internet protocol it is not limited to television streamed from the Internet. IPTV is deployed in subscriber-based telecommunications networks with high-speed access channels into end-user premises via set-top boxes or other customer-premises equipment. IPTV is used for media delivery around corporate and private networks. IPTV in the telecommunications arena is notable for its ongoing standardisation process. IPTV services may be classified into three main groups: Live television and live media, with or without related interactivity. Many different definitions of IPTV have appeared, including elementary streams over IP networks, MPEG transport streams over IP networks and a number of proprietary systems.
One official definition approved by the International Telecommunication Union focus group on IPTV is: IPTV is defined as multimedia services such as television/video/audio/text/graphics/data delivered over IP based networks managed to provide the required level of quality of service and experience, security and reliability. Another definition of IPTV, relating to the telecommunications industry, is the one given by Alliance for Telecommunications Industry Solutions IPTV Exploratory Group in 2005: IPTV is defined as the secure and reliable delivery to subscribers of entertainment video and related services; these services may include, for example, Live TV, Video On Demand and Interactive TV. These services are delivered across an access agnostic, packet switched network that employs the IP protocol to transport the audio and control signals. In contrast to video over the public Internet, with IPTV deployments, network security and performance are managed to ensure a superior entertainment experience, resulting in a compelling business environment for content providers and customers alike.
The term IPTV first appeared in 1995 with the founding of Precept Software by Judith Estrin and Bill Carrico. Precept developed an Internet video product named IP/TV. IP/TV was an Mbone compatible Windows and Unix-based application that transmitted single and multi-source audio and video traffic, ranging from low to DVD quality, using both unicast and IP multicast Real-time Transport Protocol and Real time control protocol; the software was written by Steve Casner, Karl Auerbach, Cha Chee Kuan. Precept was acquired by Cisco Systems in 1998. Cisco retains the IP/TV trademark. Internet radio company AudioNet started the first continuous live webcasts with content from WFAA-TV in January 1998 and KCTU-LP on 10 January 1998. Kingston Communications, a regional telecommunications operator in the UK, launched Kingston Interactive Television, an IPTV over digital subscriber line service in September 1999; the operator added additional VoD service in October 2001 with a VoD content provider. Kingston was one of the first companies in the world to introduce IPTV and IP VoD over ADSL as a commercial service.
The service became the reference for various changes to UK Government regulations and policy on IPTV. In 2006, the KIT service was discontinued, subscribers having declined from a peak of 10,000 to 4,000. In 1999, NBTel was the first to commercially deploy Internet protocol television over DSL in Canada using the Alcatel 7350 DSLAM and middleware created by iMagic TV; the service was marketed under the brand VibeVision in New Brunswick, expanded into Nova Scotia in early 2000 after the formation of Aliant. IMagic TV was sold to Alcatel. In 2002, Sasktel was the second in Canada to commercially deploy IPTV over DSL, using the Lucent Stinger DSL platform. In 2005, SureWest Communications was the first North American company to offer high-definition television channels over an IPTV service. In 2005, Bredbandsbolaget launched its IPTV service as the first service provider in Sweden; as of January 2009, they are not the biggest supplier any longer. In 2007, TPG became the first internet service provider in Australia to launch IPTV.
By 2010, iiNet and Telstra launched IPTV services in conjunction to internet plans. In 2008, Pakistan Telecommunication Company Limited launched IPTV under the brand name of PTCL Smart TV in Pakistan; this service is available in 150 major cities of the country offering 140 live channels. In 2010, CenturyLink – after acquiring Embarq and Qwest – entered five U. S. markets with an IPTV service called Prism. This was after successful test marketing in Florida. In 2016, Korean Central Television introduced the set-top box called Manbang providing video-on-demand services in North Korea via quasi-internet protocol television. Manbang allows viewers to watch five different TV channels in real-time, read find political information regarding the Supreme Leader and Juche ideology, read articles from state-run news organizations; the technology was hindered by low broadb
Digital television is the transmission of television signals, including the sound channel, using digital encoding, in contrast to the earlier television technology, analog television, in which the video and audio are carried by analog signals. It is an innovative advance that represents the first significant evolution in television technology since color television in the 1950s. Digital TV transmits in a new image format called HDTV, with greater resolution than analog TV, in a wide screen aspect ratio similar to recent movies in contrast to the narrower screen of analog TV, it makes more economical use of scarce radio spectrum space. A transition from analog to digital broadcasting began around 2006 in some countries, many industrial countries have now completed the changeover, while other countries are in various stages of adaptation. Different digital television broadcasting standards have been adopted in different parts of the world; this standard has been adopted in Europe, Asia, total about 60 countries.
Advanced Television System Committee uses eight-level vestigial sideband for terrestrial broadcasting. This standard has been adopted by 6 countries: United States, Mexico, South Korea, Dominican Republic and Honduras. Integrated Services Digital Broadcasting is a system designed to provide good reception to fixed receivers and portable or mobile receivers, it utilizes two-dimensional interleaving. It supports hierarchical transmission of up to three layers and uses MPEG-2 video and Advanced Audio Coding; this standard has been adopted in Japan and the Philippines. ISDB-T International is an adaptation of this standard using H.264/MPEG-4 AVC that been adopted in most of South America and is being embraced by Portuguese-speaking African countries. Digital Terrestrial Multimedia Broadcasting adopts time-domain synchronous OFDM technology with a pseudo-random signal frame to serve as the guard interval of the OFDM block and the training symbol; the DTMB standard has been adopted in the People's Republic including Hong Kong and Macau.
Digital Multimedia Broadcasting is a digital radio transmission technology developed in South Korea as part of the national IT project for sending multimedia such as TV, radio and datacasting to mobile devices such as mobile phones, laptops and GPS navigation systems. Digital TV's roots have been tied closely to the availability of inexpensive, high performance computers, it wasn't until the 1990s. In the mid-1980s, as Japanese consumer electronics firms forged ahead with the development of HDTV technology, as the MUSE analog format was proposed by Japan's public broadcaster NHK as a worldwide standard, Japanese advancements were seen as pacesetters that threatened to eclipse U. S. electronics companies. Until June 1990, the Japanese MUSE standard—based on an analog system—was the front-runner among the more than 23 different technical concepts under consideration. An American company, General Instrument, demonstrated the feasibility of a digital television signal; this breakthrough was of such significance that the FCC was persuaded to delay its decision on an ATV standard until a digitally based standard could be developed.
In March 1990, when it became clear that a digital standard was feasible, the FCC made a number of critical decisions. First, the Commission declared that the new ATV standard must be more than an enhanced analog signal, but be able to provide a genuine HDTV signal with at least twice the resolution of existing television images. To ensure that viewers who did not wish to buy a new digital television set could continue to receive conventional television broadcasts, it dictated that the new ATV standard must be capable of being "simulcast" on different channels; the new ATV standard allowed the new DTV signal to be based on new design principles. Although incompatible with the existing NTSC standard, the new DTV standard would be able to incorporate many improvements; the final standard adopted by the FCC did not require a single standard for scanning formats, aspect ratios, or lines of resolution. This outcome resulted from a dispute between the consumer electronics industry and the computer industry over which of the two scanning processes—interlaced or progressive—is superior.
Interlaced scanning, used in televisions worldwide, scans even-numbered lines first odd-numbered ones. Progressive scanning, the format used in computers, scans lines in sequences, from top to bottom; the computer industry argued that progressive scanning is superior because it does not "flicker" in the manner of interlaced scanning. It argued that progressive scanning enables easier connections with the Internet, is more cheaply converted to interlaced formats than vice versa; the film industry supported progressive scanning because it offers a more efficient means of converting filmed programming into digital formats. For their part, the consumer electronics industry and broadcasters argued that interlaced scanning was the only technology that could transmit the highest quality pictures feasible, i.e. 1,080 lines per picture and 1,920 pixels per line. Broadcasters favored interlaced scanning because their vast archive of interlaced
ISDB-T International, ISDB-Tb or SBTVD, short for Sistema Brasileiro de Televisão Digital, is a technical standard for digital television broadcast used in Brazil, Peru, Chile, Venezuela, Costa Rica, Philippines, Nicaragua, El Salvador and Uruguay, based on the Japanese ISDB-T standard. ISDB-T International launched into commercial operation on December 2, 2007, in São Paulo, Brazil, as SBTVD. ISDB-T International is called ISDB-Tb and differs from original ISDB-T by using H.264/MPEG-4 AVC as a video compression standard, a presentation rate of 30 frames per second in portable devices and powerful interaction using middleware Ginga, composed by Ginga-NCL and Ginga-J modules. The ISDB-T International standard was developed as SBTVD by a study group coordinated by the Brazilian Ministry of Communications and was led by the Brazilian Telecommunications Agency with support from the Telecommunication's Research and Development Centre; the study group was composed of members of ten other Brazilian ministries, the National Institute for Information Technology, several Brazilian universities, broadcast professional organizations, manufacturers of broadcast/reception devices.
The objective of the group was to develop and implement a DTV standard in Brazil, addressing not only technical and economical issues and mitigating the digital divide, that is, to promote inclusion of those living apart from today's information society. Another goal was to enable access to e-government, i.e. to make government closer to the population, since in Brazil 95.1% of households have at least one TV set. In January 2009, the Brazilian-Japanese study group for digital TV finished and published a specification document joining the Japanese ISDB-T with Brazilian SBTVD, resulting in a specification now called "ISDB-T International". ISDB-T International is the system, proposed by Japan and Brazil for use in other countries in South America and around the world; the history of SBTVD development can be divided in two major periods: a) Initial Studies and Tests. Since 1994 a group composed of technicians from Brazilian Society for Television Engineering and Brazilian Association of Radio and Television Broadcasters has been analyzing existing digital TV standards and its technical aspects but the discussion become a robust study only in 1998.
From 1998 to 2000, the ABERT and SET group, supported by Universidade Presbiteriana Mackenzie developed a complete study based on several tests considering not only technical characteristics of each standard but signal quality, both indoor and outdoor. That was the first complete study comparing all three major DTV standards in the world by an independent entity and it was considered a rigorous and robust study by the DTV technical world community; the results of the "Brazilian digital television tests" showed the insufficient quality for indoor reception presented by ATSC and, between DVB-T and ISDB-T, the last one presented superior performance in indoor reception and flexibility to access digital services and TV programs through non-mobile, mobile or portable receivers with impressive quality. In parallel in 1998, the Brazilian Ministry of Communication ordered the National Telecommunication Agency to carry on studies to select and implement a DTV standard in Brazil. Due to the completeness and quality of the ABERT/SET/Mackenzie study, ANATEL considered that as the official result and supported it considering ISDB-T the better standard to be implemented in Brazil.
However the final decision about the standard selected wasn't announced at that moment because of three main points: Some groups of society wanted to be more involved in that decision. In the light of those points, the Brazilian Government, created a more structured discussion group, to review the first studies and to address these new points; the program SBTVD program was deployed on November 26, 2003 by Presidential Act # 4.901, focusing the creation of a reference model for national terrestrial digital TV in Brazil. The National Telecommunications Agency was charged by the Brazilian Ministry of Communications to lead this work with the technical support of CPqD, the contributions of 10 other Brazilian ministries, the National Institute for Information Technology, 25 organizations related to the matter, 75 universities/R&D institutes and electro-electronic manufacturers. More than 1,200 researchers/professionals were mobilized; the DTV Work Group was organized in a structure with 3 areas of development: Development Committee: to define and implement a political and regulatory basis.