nc33/MultiSpan_SQUAD huggingface dataset:
High-definition_television

In 1958, the Soviet Union developed Тransformator (Russian: Трансформатор, meaning Transformer), the first high-resolution (definition) television system capable of producing an image composed of 1,125 lines of resolution aimed at providing teleconferencing for military command. It was a research project and the system was never deployed by either the military or consumer broadcasting.

Question: In the end what was the Soviet Union's Transformator system used for?
Answer: a research project

Question: When did the Soviet Union develop Transformator?
Answer: 1958

Question: Who developed Transformator in 1958?
Answer: the Soviet Union

Question: How many lines of resolution could an image using the Transformator system have?
Answer: 1,125

Question: What was the goal of the Transformator system?
Answer: providing teleconferencing for military command
High-definition_television

In 1979, the Japanese state broadcaster NHK first developed consumer high-definition television with a 5:3 display aspect ratio. The system, known as Hi-Vision or MUSE after its Multiple sub-Nyquist sampling encoding for encoding the signal, required about twice the bandwidth of the existing NTSC system but provided about four times the resolution (1080i/1125 lines). Satellite test broadcasts started in 1989, with regular testing starting in 1991 and regular broadcasting of BS-9ch commencing on November 25, 1994, which featured commercial and NHK programming.

Question: In what year did NHK first develop consumer HD television with a 5:3 aspect ratio?
Answer: 1979

Question: Who first developed consumer HD television with a 5:3 aspect ratio?
Answer: the Japanese state broadcaster NHK

Question: When did satellite test broadcasts of Hi-Vision start?
Answer: 1989

Question: When did regular broadcasting of BS-9ch start?
Answer: November 25, 1994

Question: When did regular testing of Hi-Vision start?
Answer: 1991
High-definition_television

In 1981, the MUSE system was demonstrated for the first time in the United States, using the same 5:3 aspect ratio as the Japanese system. Upon visiting a demonstration of MUSE in Washington, US President Ronald Reagan was impressed and officially declared it "a matter of national interest" to introduce HDTV to the US.

Question: When was the MUSE system demonstrated in the US first?
Answer: 1981

Question: What aspect ratio did the MUSE system use when demonstrated in 1981?
Answer: 5:3

Question: Which president declared it "a matter of national interest" to introduce HDTV to the US?
Answer: President Ronald Reagan

Question: Which system was demonstrated in the US for the first time in 1981?
Answer: MUSE

Question: Which system was demonstrated in Washington to President Ronald Reagan?
Answer: MUSE
High-definition_television

Several systems were proposed as the new standard for the US, including the Japanese MUSE system, but all were rejected by the FCC because of their higher bandwidth requirements. At this time, the number of television channels was growing rapidly and bandwidth was already a problem. A new standard had to be more efficient, needing less bandwidth for HDTV than the existing NTSC.

Question: Why did the FCC reject systems such as MUSE?
Answer: their higher bandwidth requirements

Question: What was increasing and consuming a lot of bandwidth?
Answer: television channels

Question: Who rejected systems such as MUSE as the new standard for the US?
Answer: the FCC

Question: What was one of the requirements for a new standard system in the US?
Answer: had to be more efficient, needing less bandwidth

Question: What was the existing system at the time?
Answer: NTSC
High-definition_television

The limited standardization of analog HDTV in the 1990s did not lead to global HDTV adoption as technical and economic constraints at the time did not permit HDTV to use bandwidths greater than normal television.

Question: What constraints kept HDTV from being widely adopted in the 90's?
Answer: technical and economic

Question: What was HDTV not permitted to do in the 90's?
Answer: use bandwidths greater than normal television
High-definition_television

Early HDTV commercial experiments, such as NHK's MUSE, required over four times the bandwidth of a standard-definition broadcast. Despite efforts made to reduce analog HDTV to about twice the bandwidth of SDTV, these television formats were still distributable only by satellite.

Question: How much more bandwith was required from early HDTV commercial experiments than an SD broadcast?
Answer: over four times

Question: Efforts were made to reduce analog HDTV to how much of the bandwith of SDTV?
Answer: about twice

Question: Despite the reduced bandwith, HDTV format still had to be distributed how?
Answer: by satellite

Question: What kind of experiments required over four times the bandwith of a SDTV broadcast?
Answer: Early HDTV commercial experiments
High-definition_television

In addition, recording and reproducing an HDTV signal was a significant technical challenge in the early years of HDTV (Sony HDVS). Japan remained the only country with successful public broadcasting of analog HDTV, with seven broadcasters sharing a single channel.

Question: How many broadcasters did Japan have sharing a single channel?
Answer: seven

Question: Which country had successful public analog HDTV broadcasting?
Answer: Japan

Question: What was particularly challenging in the early years of HDTV?
Answer: recording and reproducing an HDTV signal

Question: What accomplishment in early HDTV did Japan have?
Answer: the only country with successful public broadcasting of analog HDTV
High-definition_television

Since 1972, International Telecommunication Union's radio telecommunications sector (ITU-R) had been working on creating a global recommendation for Analog HDTV. These recommendations, however, did not fit in the broadcasting bands which could reach home users. The standardization of MPEG-1 in 1993 also led to the acceptance of recommendations ITU-R BT.709. In anticipation of these standards the Digital Video Broadcasting (DVB) organisation was formed, an alliance of broadcasters, consumer electronics manufacturers and regulatory bodies. The DVB develops and agrees upon specifications which are formally standardised by ETSI.

Question: What does ITU-R stand for?
Answer: International Telecommunication Union's radio telecommunications sector

Question: What does DVB stand for?
Answer: Digital Video Broadcasting

Question: What is the DVB?
Answer: an alliance of broadcasters, consumer electronics manufacturers and regulatory bodies

Question: What is the DVB's role?
Answer: develops and agrees upon specifications

Question: Who standardizes HDTV specifications?
Answer: ETSI
High-definition_television

In 1983, the International Telecommunication Union's radio telecommunications sector (ITU-R) set up a working party (IWP11/6) with the aim of setting a single international HDTV standard. One of the thornier issues concerned a suitable frame/field refresh rate, the world already having split into two camps, 25/50 Hz and 30/60 Hz, largely due to the differences in mains frequency. The IWP11/6 working party considered many views and throughout the 1980s served to encourage development in a number of video digital processing areas, not least conversion between the two main frame/field rates using motion vectors, which led to further developments in other areas. While a comprehensive HDTV standard was not in the end established, agreement on the aspect ratio was achieved.

Question: When did ITU-R start trying to work towards setting a single international HDTV standard?
Answer: 1983

Question: What did ITU-R start trying to do in 1983?
Answer: setting a single international HDTV standard

Question: What was one of the issues with setting a single HDTV standard?
Answer: a suitable frame/field refresh rate

Question: What was used as a conversion between the two main frame/field rates?
Answer: motion vectors

Question: How many frame/field rates were primarily being used in 1983?
Answer: two
High-definition_television

Initially the existing 5:3 aspect ratio had been the main candidate but, due to the influence of widescreen cinema, the aspect ratio 16:9 (1.78) eventually emerged as being a reasonable compromise between 5:3 (1.67) and the common 1.85 widescreen cinema format. An aspect ratio of 16:9 was duly agreed upon at the first meeting of the IWP11/6 working party at the BBC's Research and Development establishment in Kingswood Warren. The resulting ITU-R Recommendation ITU-R BT.709-2 ("Rec. 709") includes the 16:9 aspect ratio, a specified colorimetry, and the scan modes 1080i (1,080 actively interlaced lines of resolution) and 1080p (1,080 progressively scanned lines). The British Freeview HD trials used MBAFF, which contains both progressive and interlaced content in the same encoding.

Question: What aspect ratio was agreed upon due to the influence of widescreen cinema?
Answer: 16:9

Question: Who agreed upon the 16:9 aspect ratio?
Answer: the IWP11/6 working party

Question: What was a leading factor in the 16:9 aspect ratio being chosen?
Answer: widescreen cinema

Question: Which encoding contains both progressive and interlaced content?
Answer: MBAFF

Question: Which aspect ratio was the early favorite?
Answer: 5:3
High-definition_television

It also includes the alternative 1440×1152 HDMAC scan format. (According to some reports, a mooted 750-line (720p) format (720 progressively scanned lines) was viewed by some at the ITU as an enhanced television format rather than a true HDTV format, and so was not included, although 1920×1080i and 1280×720p systems for a range of frame and field rates were defined by several US SMPTE standards.)

Question: What scan format is also included in MBAFF?
Answer: 1440×1152 HDMAC

Question: What was viewed by some as enhanced television format and not true HDTV format?
Answer: a mooted 750-line

Question: A mooted 750-line was seen by some at the ITU as what?
Answer: an enhanced television format

Question: What were 1920x1080i and 1280x720p defined by?
Answer: US SMPTE standards
High-definition_television

HDTV technology was introduced in the United States in the late 1980s and made official in 1993 by the Digital HDTV Grand Alliance, a group of television, electronic equipment, communications companies consisting of AT&T Bell Labs, General Instrument, Philips, Sarnoff, Thomson, Zenith and the Massachusetts Institute of Technology. Field testing of HDTV at 199 sites in the United States was completed August 14, 1994. The first public HDTV broadcast in the United States occurred on July 23, 1996 when the Raleigh, North Carolina television station WRAL-HD began broadcasting from the existing tower of WRAL-TV southeast of Raleigh, winning a race to be first with the HD Model Station in Washington, D.C., which began broadcasting July 31, 1996 with the callsign WHD-TV, based out of the facilities of NBC owned and operated station WRC-TV. The American Advanced Television Systems Committee (ATSC) HDTV system had its public launch on October 29, 1998, during the live coverage of astronaut John Glenn's return mission to space on board the Space Shuttle Discovery. The signal was transmitted coast-to-coast, and was seen by the public in science centers, and other public theaters specially equipped to receive and display the broadcast.

Question: When was HDTV introduced in the US?
Answer: late 1980s

Question: Who made HDTV official in 1993?
Answer: the Digital HDTV Grand Alliance

Question: AT&T, Philips, Zenith, and MIT, among others, made up what group in the 90's?
Answer: the Digital HDTV Grand Alliance

Question: When did the first public HDTV broadcast happen in the US?
Answer: July 23, 1996

Question: What does ATSC stand for?
Answer: Advanced Television Systems Committee
High-definition_television

The first HDTV transmissions in Europe, albeit not direct-to-home, began in 1990, when the Italian broadcaster RAI used the HD-MAC and MUSE HDTV technologies to broadcast the 1990 FIFA World Cup. The matches were shown in 8 cinemas in Italy and 2 in Spain. The connection with Spain was made via the Olympus satellite link from Rome to Barcelona and then with a fiber optic connection from Barcelona to Madrid. After some HDTV transmissions in Europe the standard was abandoned in the mid-1990s.

Question: When did the first HDTV transmissions happen in Europe?
Answer: 1990

Question: What event was the first HDTV broadcast in Europe?
Answer: FIFA World Cup

Question: When did Europe abandon standard transmission?
Answer: mid-1990s

Question: Where was the FIFA World Cup able to be watched in HDTV?
Answer: 8 cinemas in Italy and 2 in Spain
High-definition_television

The first regular broadcasts started on January 1, 2004 when the Belgian company Euro1080 launched the HD1 channel with the traditional Vienna New Year's Concert. Test transmissions had been active since the IBC exhibition in September 2003, but the New Year's Day broadcast marked the official launch of the HD1 channel, and the official start of direct-to-home HDTV in Europe.

Question: When did regular broadcasts start in Europe?
Answer: January 1, 2004

Question: What event was first broadcasted on January 1, 2004?
Answer: Vienna New Year's Concert

Question: The New Year's Day broadcast officially launched which channel?
Answer: HD1

Question: When did test transmissions of HDTV begin in Europe?
Answer: September 2003

Question: Which European company launched HD1?
Answer: Euro1080
High-definition_television

Euro1080, a division of the former and now bankrupt Belgian TV services company Alfacam, broadcast HDTV channels to break the pan-European stalemate of "no HD broadcasts mean no HD TVs bought means no HD broadcasts ..." and kick-start HDTV interest in Europe. The HD1 channel was initially free-to-air and mainly comprised sporting, dramatic, musical and other cultural events broadcast with a multi-lingual soundtrack on a rolling schedule of 4 or 5 hours per day.

Question: Euro1080 was a division of what former company?
Answer: Alfacam

Question: What "chicken or the egg" stalemate prompted Euro1080 to broadcast HDTV channels?
Answer: "no HD broadcasts mean no HD TVs bought means no HD broadcasts ..."

Question: What was Euro1080 hoping to kick-start by broadcasting HDTV channels?
Answer: HDTV interest in Europe

Question: How much did viewers have to pay for the HD1 channel?
Answer: free-to-air

Question: What was on HD1 for 4 or 5 hours per day?
Answer: a multi-lingual soundtrack on a rolling schedule
High-definition_television

These first European HDTV broadcasts used the 1080i format with MPEG-2 compression on a DVB-S signal from SES's Astra 1H satellite. Euro1080 transmissions later changed to MPEG-4/AVC compression on a DVB-S2 signal in line with subsequent broadcast channels in Europe.

Question: What format did the first European HDTV broadcast use?
Answer: 1080i format

Question: What compression did the first European HDTV broadcast use?
Answer: MPEG-2

Question: What signal did the first European HDTV broadcast use?
Answer: DVB-S

Question: What compression did Euro1080 later change to?
Answer: MPEG-4/AVC

Question: What signal did Euro1080 later change to?
Answer: DVB-S2
High-definition_television

Despite delays in some countries, the number of European HD channels and viewers has risen steadily since the first HDTV broadcasts, with SES's annual Satellite Monitor market survey for 2010 reporting more than 200 commercial channels broadcasting in HD from Astra satellites, 185 million HD capable TVs sold in Europe (£60 million in 2010 alone), and 20 million households (27% of all European digital satellite TV homes) watching HD satellite broadcasts (16 million via Astra satellites).

Question: According to the 2010 Satellite Monitor market survey, how many HD capable TV's were sold in Europe?
Answer: 185 million

Question: According to the 2010 Satellite Monitor market survey, how many European households were watching HD broadcasts? 
Answer: 20 million

Question: How many pounds were spent in Europe on HD capable TVs in 2010?
Answer: £60 million

Question: What percentage of European digital satellite TV homes were watching HD broadcasts in 2010?
Answer: 27%

Question: The number of European HD channels and viewers has done what since the first HDTV broadcasts?
Answer: risen steadily
High-definition_television

In December 2009 the United Kingdom became the first European country to deploy high definition content using the new DVB-T2 transmission standard, as specified in the Digital TV Group (DTG) D-book, on digital terrestrial television.

Question: Which European country first deployed HD content using the new DVB-T2 standard?
Answer: the United Kingdom

Question: When did the UK deploy HD content using the new DVB-T2 transmission standard?
Answer: December 2009

Question: What transmission standard did the UK start using in December 2009?
Answer: DVB-T2

Question: What does DTG stand for?
Answer: Digital TV Group
High-definition_television

The Freeview HD service currently contains 10 HD channels (as of December 2013[update]) and was rolled out region by region across the UK in accordance with the digital switchover process, finally being completed in October 2012. However, Freeview HD is not the first HDTV service over digital terrestrial television in Europe;

Question: How many HD channels did the Freeview HD service contain as of December 2013?
Answer: 10

Question: When was the digital switchover process completed in the UK?
Answer: October 2012

Question: Which service contains 10 HD channels and finished its roll out in October 2012?
Answer: Freeview HD

Question: How was the Freeview HD service rolled out in the UK?
Answer: region by region
High-definition_television

If all three parameters are used, they are specified in the following form: [frame size][scanning system][frame or field rate] or [frame size]/[frame or field rate][scanning system].[citation needed] Often, frame size or frame rate can be dropped if its value is implied from context. In this case, the remaining numeric parameter is specified first, followed by the scanning system.

Question: What are the three HDTV parameters?
Answer: [frame size][scanning system][frame or field rate]

Question: Which two parameters can be dropped if its value is implied from context?
Answer: frame size or frame rate

Question: When can the frame size or frame rate parameter specification be dropped?
Answer: if its value is implied from context

Question: When a parameter is dropped, the remaining numeric parameter is specified first, followed by what?
Answer: the scanning system
High-definition_television

For example, 1920×1080p25 identifies progressive scanning format with 25 frames per second, each frame being 1,920 pixels wide and 1,080 pixels high. The 1080i25 or 1080i50 notation identifies interlaced scanning format with 25 frames (50 fields) per second, each frame being 1,920 pixels wide and 1,080 pixels high. The 1080i30 or 1080i60 notation identifies interlaced scanning format with 30 frames (60 fields) per second, each frame being 1,920 pixels wide and 1,080 pixels high. The 720p60 notation identifies progressive scanning format with 60 frames per second, each frame being 720 pixels high; 1,280 pixels horizontally are implied.

Question: What size is each 1920x1080p25 frame?
Answer: 1,920 pixels wide and 1,080 pixels high

Question: The 1920x1080p25 notion identifies progressive scanning format with how many frames per second?
Answer: 25

Question: The 1080i25 or 1080i50 notion identifies interlaced scanning format with how many frames per second?
Answer: 25

Question: The 1080i30 or 1080i60 notion identifies interlaced scanning format with how many frames per second?
Answer: 30

Question: The 720p60 notion identifies progressive scanning format with how many frames per second?
Answer: 60
High-definition_television

For the commercial naming of a product, the frame rate is often dropped and is implied from context (e.g., a 1080i television set). A frame rate can also be specified without a resolution. For example, 24p means 24 progressive scan frames per second, and 50i means 25 interlaced frames per second.

Question: What is usually dropped for the commercial naming of an HDTV product?
Answer: the frame rate

Question: What does 24p mean?
Answer: 24 progressive scan frames per second

Question: What does 50i mean?
Answer: 25 interlaced frames per second

Question: When naming a commercial HDTV product, a frame rate can be specified without what?
Answer: a resolution
High-definition_television

There is no single standard for HDTV color support. Colors are typically broadcast using a (10-bits per channel) YUV color space but, depending on the underlying image generating technologies of the receiver, are then subsequently converted to a RGB color space using standardized algorithms. When transmitted directly through the Internet, the colors are typically pre-converted to 8-bit RGB channels for additional storage savings with the assumption that it will only be viewed only on a (sRGB) computer screen. As an added benefit to the original broadcasters, the losses of the pre-conversion essentially make these files unsuitable for professional TV re-broadcasting.

Question: Is there a single standard for HDTV color support?
Answer: no

Question: Before being converted to RGB, colors are ususally broadcasted using what color space?
Answer: YUV

Question: Colors are typically broadcast using YUV and then converted to what?
Answer: a RGB color space

Question: When transmitted over the internet, colors are typically to what?
Answer: 8-bit RGB channels

Question: What assumption is made with colors being transmitted over the internet?
Answer: it will only be viewed only on a (sRGB) computer screen
High-definition_television

At a minimum, HDTV has twice the linear resolution of standard-definition television (SDTV), thus showing greater detail than either analog television or regular DVD. The technical standards for broadcasting HDTV also handle the 16:9 aspect ratio images without using letterboxing or anamorphic stretching, thus increasing the effective image resolution.

Question: At least how many times more linear resolution does HDTV have over SDTV?
Answer: twice

Question: HDTV increases the effective image resolution by not using what?
Answer: letterboxing or anamorphic stretching

Question: What does SDTV stand for?
Answer: standard-definition television

Question: HDTV handles what aspect ratio without using letterboxing or anamorphic stretching?
Answer: 16:9
High-definition_television

A very high resolution source may require more bandwidth than available in order to be transmitted without loss of fidelity. The lossy compression that is used in all digital HDTV storage and transmission systems will distort the received picture, when compared to the uncompressed source.

Question: If more bandwith is required than is available, a very high resolution source my not be able to transmitted without loss of what?
Answer: fidelity

Question: The compression used in all HDTV storage and transmission systems will do what if resolution is too high?
Answer: distort the received picture

Question: A very high resolution source may require more of what?
Answer: bandwidth
High-definition_television

The optimum format for a broadcast depends upon the type of videographic recording medium used and the image's characteristics. For best fidelity to the source the transmitted field ratio, lines, and frame rate should match those of the source.

Question: A broadcasts optimum format depends on what two things?
Answer: the type of videographic recording medium used and the image's characteristics

Question: For best fidelity to the source, what three things should match the source? 
Answer: transmitted field ratio, lines, and frame rate

Question: For best fidelity to the source, the transmitted field ratio, lines, and frame rate should match what? 
Answer: those of the source

Question: The type of videographic recording medium used and the image's characteristics determine what?
Answer: The optimum format for a broadcast