UHDTV resolution shown in comparison to HD and SD formats

Ultra High Definition Television (or UHDTV, 4320p, and 8K) is a digital video format proposed by NHK Science & Technology Research Laboratories. It has a resolution of 16 times the number of pixels of the 1080p high-definition television standard, which brings it to roughly the detail level of IMAX.^[1][2] NHK advocates this video format as Super Hi-Vision.

History[link]

SMPTE first released Standard 2036 for UHDTV in 2007.^[4] UHDTV was defined as having two levels called UHDTV1 (3840x2160 or 4K) and UHDTV2 (7680x4320 or 8K).^[4][5] Before 2011, UHDTV allowed for frame rates of 24, 25, 50, and 60 frames per second.^[5] In a ITU-R meeting during 2011, an additional frame rate was added to UHDTV of 120 frames per second.^[6]

NHK researchers had to build their own UHDTV prototype from scratch. In the system demonstrated in September 2003, they used an array of 16 HDTV recorders to capture the 30-minute-long test footage. The camera itself was built with four 2.5 inch (64 mm) CCDs, each with a resolution of only 3840 × 2048. Using two CCDs for green and one each for red and blue, they then used a spatial pixel offset method to bring it to 7680 × 4320.^[7][8] The system was demonstrated at Expo 2005, Aichi, Japan, the NAB 2006 and NAB 2007 conferences, Las Vegas, at IBC 2006 and IBC 2008,^[9] Amsterdam, Netherlands, and CES 2009. A review of the NAB 2006 demo was published in a Broadcast Engineering e-newsletter.^[10]

In November 2005, NHK demonstrated a live relay of a UHDTV program over a distance of 260 km by a fibre optic network. Using dense wavelength division multiplex (DWDM), 24 Gbit/s speed was achieved with a total of 16 different wavelength signals.

On December 31, 2006, NHK demonstrated a live relay of their annual Kōhaku Uta Gassen over IP from Tokyo to a 450 inch (11.4 m) screen in Osaka. Utilizing a codec developed by NHK, the video was compressed from 24 Gbit/s to 180–600 Mbit/s and the audio was compressed from 28 Mbit/s to 7–28 Mbit/s.^[11] Uncompressed, a 20 minute broadcast would require roughly 4 TB of storage. In another indoor demonstration at the NHK Open House, the UHDTV signal was compressed to a 250 Mbit/s MPEG2 stream. This was later input to a 300 MHz wide band modulator and broadcast using a 500 MHz QPSK modulation. This "on the air" transmission had a very limited range (less than 2 metres), but shows the feasibility of a satellite transmission in the 36,000 km orbit.

In 2008, Aptina Imaging announced the introduction of a new CMOS Image sensor specifically designed for the NHK UHDTV project.^[12] During IBC 2008 Japan's NHK, Italy's RAI, BSkyB, Sony, Samsung, Panasonic Corporation, Sharp Corporation, and Toshiba (with various partners) demonstrated the first ever public live transmission of UHDTV, from London to the conference site in Amsterdam.^[13][14]

On September 29, 2010, the NHK partnered up and recorded The Charlatans live in the UK in the UHDTV format, before broadcasting over the internet to Japan.^[15]

On May 19, 2011, SHARP in collaboration with NHK demonstrated a direct-view 85" LCD display capable of 7680 x 4320 pixels at 10 bpp.^[16]

On February 23, 2012, NHK announced that with Shizuoka University they had developed an 8K (7680 x 3840) sensor that could shoot video at 120 frames per second.^[17][18][19]

In April 2012, NHK (in collaboration with Panasonic) announced a 145-inch display (7680 x 4320 at 60 fps), that has 33.2 million 0.417 mm square pixels.^[20]

In May 2012, NHK showed the world's first Ultra High Definition shoulder-mount camera. By reducing the size and weight of the camera, the portability had been improved, making it more maneuverable than previous prototypes, so it can be used in a wide variety of shooting situations. The single-chip sensor uses a Bayer color filter array, where only one color component is acquired per pixel. Researchers at NHK have also developed a high quality up-converter, which estimates the other two color components to convert the output into full resolution video.^[21]

Also, the same month, NHK showed the Ultra High Definition imaging system it has developed in conjunction with Shizuoka University, that outputs 33 MP video at 120 FPS. As Ultra High Definition broadcasts at full resolution are designed for large, wall sized displays, there is a possibility that fast moving subjects may not be clear when shot at 60 FPS, so the option of 120 FPS has been standardized for these situations. To handle the sensor output of approximately 4 billion pixels per second with a data rate as high as 51.2 Gbps, a faster analog-to-digital converter has been developed to process the data from the pixels, and then a high-speed output circuit distributes the resulting digital signals into 96 parallel channels. This 1.5-inch CMOS sensor is smaller and uses less power when compared to conventional Ultra High Definition sensors, and it is also the world's first to support the full specifications of the Ultra High Definition standard.^[22]

The final goal is for UHDTV to be available in domestic homes, though the timeframe for this happening varies between 2015 to 2020 but Japan and China may get it in the 2013-2014 time frame.^[23] BBC intends to trial UHDTV during the 2012 Summer Olympics, erecting 15 m display screens at three locations.^[24]

Standards that deal with UHDTV include:

• Rec. ITU-R BT.1201-1 (2004)
• Rec. ITU-R BT.1706 (2006)
• SMPTE 2036-1 (2009)
• SMPTE 2036-2 (2008)
• SMPTE 2036-3 (2010)

• 

  Prototype Camera head (2006)

• 

  Prototype Camera head (2009)

See also[link]

• 22.2 surround sound - the audio component of UHDTV
• IMAX - a digital theater format that historically has been innovative in creating a more realistic viewing experience
• High Efficiency Video Coding (HEVC)

Notes and references[link]

External links[link]

Official sites of NHK

• NHK Super Hi-Vision
• NHK Science & Technical Research Laboratories
• Annual report 2009 about NHK STRL, Super Hi-Vision research

Video

• The TV format to replace HD BBC News Online

Articles

• What is Ultra HDTV?
• Ultra high resolution television (UHDV) prototype CD Freaks
• Just Like High-Definition TV, but With Higher Definition The New York Times
• Japan demonstrates next-gen TV broadcast Electronic Engineering Times
• Europe gets glimpse of HD future BBC News Online
• Researchers craft HDTV's successor PC World (magazine)
• Super Hi-Vision — research on a future ultra-HDTV system Masayuki Sugawara, EBU Technical Review
• Farewell to the Kingdom of Shadows A filmmaker's first impression of Super Hi-Vision television