Цифрлік теледидар стандарты: ISDB-T International

Technical standard for digital televisions

ISDB T International, also known in Brazil as Sistema Brasileiro de Televisão Digital (SBTVD; ), is a technical standard for digital television broadcast used in Brazil, Argentina, Peru, Botswana, Chile, Honduras, Venezuela, Ecuador, Costa Rica, Paraguay, Philippines, Bolivia, Nicaragua, El Salvador and Uruguay, based on the Japanese ISDB T standard. ISDB T International launched into commercial operation on 2 December 2007, in São Paulo, Brazil. It is similar to ISDB T, except it utilizes the H.264 video codec rather than MPEG 2, and replaces BML with Ginga—a middleware supporting Nested Context Language (NCL) and Java based interactive TV applications. 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 (ANATEL) with support from the Telecommunication's Research and Development Centre (CPqD). The study group was composed of members of ten other Brazilian ministries, the National Institute for Information Technology (ITI), several Brazilian universities, broadcast professional organizations, and manufacturers of broadcast/reception devices. The objective of the group was to develop and implement a digital terrestrial television standard in Brazil, addressing not only technical and economical issues, but also and mainly 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 that is 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; b) Implementation of Digital TV Work Group and final definition of SBTVD standard.

Some months after Presidential Act number 5.820, in November 2006, the SBTVD Forum was created to lead and coordinate technical discussions about the standard, to create all related documentation (in conjunction with ABNT (Associação Brasileira de Normas Técnicas; Brazilian Association for Technical Standards)) and to plan further developments.

Samsung was the first company to do a public demonstration of SBTVD transmissions and receivers on June 19, 2007, although other companies claimed to have receivers ready at the time. At their showroom in São Paulo, two Full HD LCD sets were shown: one with a built in tuner and another connected to a prototype set top box. The tuner and set top box were developed in Brazil, at Samsung's research center in Manaus, Amazonas. 1seg broadcasting to mobile devices was also shown. The signal was a test reel from Rede Globo, broadcast at 1080i (the standard does not define 1080p) consisting of short clips from soap operas, talk shows, soccer games from recent years and footage of the Brazilian Carnival in Rio de Janeiro along with some scenic views. All content was natively HD, some of which was shot with high definition cameras experimentally placed in many of the studios where Globo produces its programs. The 2007 Pan American Games were also experimentally broadcast in high definition by Globo. Broadcasts of the event could be seen both from Samsung's show room and electronics megastores that received digital tuners to show and demonstrate the technology to the public.

Regular SBTVD broadcasts started on December 2, 2007, initially in São Paulo. By January 2008, the system had also launched in these other Brazilian cities: Rio de Janeiro, Belo Horizonte, Goiânia, Porto Alegre, Curitiba, Campinas, Cuiabá, Salvador, Florianópolis, Vitória, Uberlândia, São José do Rio Preto, Teresina, Santos, Brasília, Campo Grande, Fortaleza, Recife, João Pessoa, Sorocaba, Mogi das Cruzes, Ribeirão Preto, Manaus, Belém, Joinville, Aracaju, Londrina, São Luís, Araraquara and Natal. In the beginning, from the broadcasters' point of view, the DTV implementation in Brazil seemed to be very successful if compared with the implementation process in other countries. After 16 months, the digital TV signal covered almost 50% of the Brazilian population. The country successfully finished the transition from analog to digital TV in December 2018, when analog TV was phased out in most regions where it was still broadcasting. Citizens with low income who still had old TV sets (i. e. unable to receive digital TV) were given set top boxes to enable them to continue watching TV. However, there are some less populated regions where the regulator accepted phasing out to be postponed to 2023. A new push in set top box and DTV sets sales was expected with the final specification of Ginga middleware that will allow interactive use of TV. Ginga 1.0 (a first implementation of Ginga) was already released for use by set top box/DTV manufacturers, using NCL (Nested Context Language)/Lua as its declarative programming language. That part of Ginga is called Ginga NCL. However, the complete Ginga middleware specification was planned to present the declarative NCL module and procedural Java module to allow programmers, manufacturers and users to take the best from the two environments: declarative and procedural. The Java part of Ginga, called Ginga J, had its specification approved by the SBTVD Forum in April 2009. The same forum declared that the APIs set developed by Sun Microsystems, called Java DTV, is the standard for SBTVD system, after negotiations with Sun Microsystems to reduce royalties in 15%. Hence, the royalty cost defined by Sun for Java DTV is much more affordable than that charged by GEM APIs owners (GEM middleware is used in DVB T the European DTV standard). That will benefit development of interactive set top boxes and TV sets keeping them cheaper than if GEM was used as middleware or even if GEM APIs were used with Ginga J. In the 3rd quarter 2009 the first set top boxes and TV sets with complete Ginga middleware (Ginga NCL and Ginga J) were available in the market. That date match with the release of first interactive programs to be broadcast by television companies. At launch on December 2, 2007, set top boxes were available for prices ranging between R$900 (~US$450) and R$1200 (~US$600), inhibiting sales. But after 8 months the prices dropped quickly to around R$300 (~US$150). The Federal Government announced subsidies worth 1 billion Reais (~US$556 million) so these prices faced a new reduction phase. By May 2009 a 42 inch LCD TV full HD (1920×1080) with built in digital TV tuner and special characteristics such as double presentation rate (120 Hz) and exceptional contrast (50.000:1) was being sold for R$3,600.00 (~US$1,800.00) in São Paulo City, a very impressive price reduction for such a quality product, and other basic devices present even lower prices. However, until September 2009 the smallest TV that could be bought with an integrated digital tuner was a 32 inch LCD TV. This was slowing down the adoption of digital TV in Brazil, since most people that watch FTA TV cannot afford buying expensive LCD TVs, and 21 and 29 inch CRT TVs were still very popular among the low income population and could be bought for about R$400–600 (US$200–300). From 2010 on, it was mandated that all TV sets sold in Brazil to be ISDB T compatible. Furthermore, in the period between 2009 and 2013, Brazil's economy improved, which encouraged family consumption. This, associated with a rapid drop in prices of LCD and LED backlit TVs quickly led to a more widespread usage of DTV. In December 2018, Brazil phased out analog transmissions in most of the country, leaving some regions to phase out analog transmissions to 2023. A massive distribution program of set top boxes to low income citizens who still had old TV sets (therefore unable to receive ISDB T) was performed between 2015 and 2018. As of 2021, LED backlit TV are much more affordable (like in most of the world), a 40" LED backlit TV can be bought for about US$300.00. Sales of mobile receivers (for laptops, mobile DTV sets and mobile phones with a built in DTV receiver) were increasing very fast and it seems that mobility was perceived by consumers as a more attractive SBTVD/ISDB T feature than HD or Full HD definition. The SBTVD/ISDB T standard allows a very impressive mobile reception, with high quality and steady image, without noise, excellent audio and very robust reception even in the presence of signal reflection, electromagnetic or impulsive interference. Peru, Argentina, Chile and Venezuela were planning the deployment before announcing their analog shutdown date.

This innovative feature of the ISDB T standard allows a consumer to watch three different programs at once, or in a sports match, it is possible to watch the game from the point of view of different cameras. The Brazilian Ministry of Communication prevented commercial broadcast companies from using this feature; only public DTV channels are allowed to use it. This decision was taken because Multiprogram could allow unauthorized use of the TV broadcast band. To start with, the Ministry of Communication informed that legal support was being created to the allow the use of such a feature, but later decided that the feature will be blocked until new studies are performed. TV Globo and ABRA (Association of Broadcasting Companies) are pushing the Ministry to keep the Multiprogram feature blocked because it will impact the current TV business model, reducing revenues from advertising. However, once users see the benefit of the Multiprogram feature, some organizations are asking that the Ministry of Communication will allow its use by all broadcasters. Some broadcasters, using a different business model from that used by TV Globo, are asking the Federal Superior Court to decide if the Multiprogram blockage is legal. Only federal government TV channels are allowed to use Multiprogram in Brazil today. TV Cultura, a public television station from the state of São Paulo, obtained special authorization (for educational purposes only) and is currently using this feature to broadcast four different video programs. Besides the HDTV and the one segment (handheld) streams, an additional archive program (Multicultura) and the Virtual University channel (UNIVESP) have been on air since August 2009. In Japan Multiprogram has been successful with the launch of ISDB T there.

Brazilian broadcasters defend the use of the current analog TV VHF band for the "return channel", the channel that allows digital TV sets to send data to broadcasters as part of an interactive TV service. That 700 MHz band enables the return channel using WiMAX technology, which would be another option to be added to the regular ones (ADSL Internet, Cable Internet, GSM EDGE, GSM 3G, WiFi or dial). That idea was to be presented to the Brazilian Government in the WiMAX Forum in June 2009, in the hope of creating an international standard for the return channel.

The Brazilian and Japanese governments are working together to show the benefits of SBTVD (ISDB Tb) standard to all South American countries, focusing specially on the social benefits of digital inclusion through DTV and quality of image, sound and robustness of ISDB T system as well as mobility and interaction.