November/December 2019

More articles in this issue:

• The Future of Travel
• Innovation Entrepreneur Awards Celebrate Life-Changing Tech
• Health Sensing in Cars
• Quibi CEO Meg Whitman
• Biometrics: You and Only You

CTA develops essential industry standards and recommended practices to enable interoperability between new products and existing devices. CTA has developed a vast number of industry standards that cover topics such as television, augmented/virtual reality, artificial intelligence, cybersecurity, and wearables, but our most popular standard continues to be CTA-861, A DTV Profile for Uncompressed High-Speed Digital Interfaces. You may not know CTA-861, but chances are you’ve used it. The ubiquitous HDMI interface relies on CTA-861.

This standard was first written around the turn of the century, when CTA was still known as the Consumer Electronics Association. The first version of this standard was published in January 2001, but has received many revisions, amendments and extensions throughout the years, and CTA is currently working on the eighth revision, which will result in CTA-861-H.

CTA-861 describes how digital audio/video signals can be sent from one device to another. Digital interfaces, such as HDMI, in consumer electronics products like digital TVs, digital set-top boxes (cable or satellite) and DVD players make use of CTA-861. Devices that send the digital AV signals are called sources, and devices that receive the signals, namely TVs and monitors, are called sinks.

Important Updates

Throughout the years this standard has gone through major changes. Initially it was a video-only standard but was quickly updated to include the carriage of audio. The video resolution specified by the standard has increased over the years, from HD to UHD and beyond. Advanced audio and High Dynamic Range (HDR) video have been accommodated in recent years. Other industry organizations such as the HDMI Forum, the Society of Motion Picture and Television Engineers (SMPTE) and Blu-ray Disc Association (BDA) continue to use and reference CTA-861 to this day.

The revision CTA is working on now, which will eventually result in CTA-861-H, involves many vital updates and modifications that will help the industry. First, it will include two recent extensions that were created soon after the previous version was created. One extension deals with dynamic HDR metadata/colorimetry and the second is focused on audio, adding support for MPEG-H 3DA capabilities, ITU-R BS.2051 System H 22.2 multichannel sound, and audio coding extension types ATRAC-X, MPEG-4 ALS, and Auro-CX. Other major additions include things like the BT.2100 specification update, quantization range update, timing formats and reference updates. These technical upgrades mean more options for better video, color and sound. The estimated completion date for CTA-861-H is mid-2020.

Testing at PlugFest At the request of the industry in 2003, CTA created an interoperability testing event for the industry, known as PlugFest. It was the early days for HDMI, and there were interoperability problems. The event provided a testbed for digital interfaces (DVI, HDMI and IEEE 1394) between cables boxes and TVs. PlugFest is a secure place where companies meet to test their products with other industry products to ensure they are compatible with each other. PlugFests are well-attended and always receive positive feedback.

CTA-861 has been important to the industry for almost 20 years and continues to be one of the leading HDMI-related standards. The industry continues to rely on this standard and CTA is committed to making the necessary updates to keep it relevant.