High-Definition Multimedia Interface® (HDMI®) 1.4 is a version of HDMI® that brought several new features and abilities to entertainment systems that utilize HDMI®. These include Ethernet data and audio return channels added to the HDMI® cable, a smaller 19-pin connector cable, higher resolution support, and definitions for three-dimensional (3-D) format and resolutions. The improvements introduced in HDMI® 1.4 were primarily aimed at reducing the amount of cables necessary to properly set up advanced home entertainment systems, and to prepare for advancements in home entertainment such as high definition televisions (HDTVs) with resolutions beyond 1080p and those incorporating 3-D technology.
First released in 2002, HDMI® was developed to create an audio-video cable for HDTVs that would be backward-compatible with digital visual interface (DVI) connectors that were primarily in use at the time. The original version of HDMI® was designed to be compatible with DVI and could be used with an adapter without signal loss. Since then, multiple versions of HDMI® have been released, each with upgrades and new technology to increase the usefulness and improve the abilities of HDMI® enabled devices.
With HDMI® 1.4, released in 2009, devices were enabled to further communicate with each other through a properly set up system and to utilize advances in technology for years to follow. With the additions of Ethernet and audio return channels to HDMI® cables in HDMI® 1.4, fewer cables are required to properly set up a home entertainment system. The Ethernet channel allows bi-directional data streams between devices and an HDTV. This means that a properly set up system, with Internet Protocol (IP) enabled devices need only have a single Internet connection between the HDTV and the Internet. The Ethernet channel in the HDMI® 1.4 cable can allow transfer rates up to 100 megabytes per second (Mb/sec) between the Internet and the HDTV as well as the devices plugged in to the HDTV.
HDMI® 1.4 also introduced an audio return channel in the cable that eliminated the need for a separate audio cable to allow data to go “upstream” from an HDTV to an audio receiver device. This was primarily helpful for users with an HDTV that had a built-in tuner or digital versatile disc (DVD) player who needed to send audio information from the HDTV to a receiver for elaborate home entertainment systems. This advancement reduces the need for a separate cable to allow audio data to travel out from an HDTV to a receiver.
A micro HDMI® connector was also introduced with HDMI® 1.4 that is about half the size of previous mini connectors and allowed for better resolution, up to 1080p, in portable devices. HDMI® 1.4 also established support for HDTVs with resolutions up to four times greater than 1080p. Referred to as 4K x 2K, or about 4,000 lines wide by 2,000 lines high, or simply 4K, these resolutions are about equivalent to what is found in commercial theaters using digital cinema projectors.
HDMI® 1.4 established the first standards for 3-D support in HDTVs. Though HDMI® 1.4 set several standards and protocols for 3-D displays, further specifications and mandatory formats were established in HDMI® 1.4a, released in March of 2010. Both releases were aimed at preparing HDMI® compatible devices for use with HDTVs developed to support and allow 3-D movie viewing, gaming, and broadcasting.