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U-SDI - Signal Interface for 8K/4K Video and 22.2 Multichannel Audio

Technology for transmitting large-volume 8K signals over a single cable


We have developed an ultra high-definition interface,“U-SDI*1”, that can transmit full-specification 8K video signals, which have about 100 times the data volume of Hi-Vision, over a single cable. We have also developed a 22.2 multichannel sound multiplexing device that enables simultaneous transmission of video and sound signals for program production.


●Optical interface to transmit a large volume of signals using a single cable

Transmission of full-specification 8K signals (approx. 144 Gbps) previously required a lot of effort, including connecting about 100 coaxial cables. The U-SDI enables full-specification 8K signals to be transmitted over a single cable and makes it easy to connect production devices such as cameras and recorders by using an optical multicable and its unique signal mapping technology.

●22.2 multichannel sound multiplexing device

We have developed a device*2 to multiplex 22.2 channel sound signals in the auxiliary spaces of video signal mapping. This technology makes it possible for the U-SDI, which previously could transmit only video, to handle sound as well as video.

●Towards an international standard

This interface specification was adopted as a domestic standard*3 at the Association of Radio Industries and Businesses (ARIB) in March 2014. Since then, standardization efforts have been in progress at the Society of Motion Picture and Television Engineers (SMPTE) and the International Telecommunication Union Radiocommunications Sector (ITU-R).

Future plans

We are studying practical applications and ways to reduce the cost of devices equipped with this interface in preparation for the start of 8K broadcasting. We are also developing a method to transmit other data required for program production, such as time codes, and continuing with the international standardization effort.

*1 U-SDI: Ultrahigh-definition Signal/Data Interface
*2 New device: The sound multiplexing technology was adopted as a domestic standard (ARIB STD-B64) in March 2015.
*3 Domestic standard: ARIB STD-B58 “Interface for Ultra-High-Definition TV Production Systems”

Appearance of cable and interface specifications
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