Next-Gen HDMI Expands Range of Applications

The High-Definition Multimedia Interface (HDMI) has become indispensible for equipment handling high-definition television (HDTV) imagery, such as flatscreens and digital videodisc (DVD) players. The next-generation specification will be released in the first half of 2009 (Table 1), according to the policy statement announced in January 2009 by HDMI Licensing LLC of the US, the group responsible for drawing up the specs. There are two main points, namely an expanded range of HDMI application sectors, and function expansion.

Newly targeted application sectors include compact, mobile equipment such as mobile phones, and automotive equipment like car navigation systems. The organization believes that these and other sectors will see rising demand for HDTV imagery capability in the future. New connector specifications will be defined for the new application sectors, such as compact and automotive equipment.

For example, connector dimensions will be even smaller for compact equipment. The connector specification used for mobile gear now is the Type C, as defined in the existing Ver 1.3a HDMI specification. Type C can be used on camcorders, but there have been complaints from the industry that it is still too big for compact digital cameras, mobile phones, etc. The next-generation connector will keep the same 19 pins, but be considerably smaller. The industry has already been buzzing with rumors about the new, smaller connector, and the announcement officially confirmed them.

4K x 2K Resolution
Functional expansions in HDMI are moving in three directions: (1) support for 4096 x 2160 pixels ("4K x 2K") resolution, three-dimensional (3D) imagery etc; (2) enhanced network functions; and (3) expanded audio functions.

Improved imagery support (1) will be implemented through a boosted max data transfer rate. Under the existing Ver 1.3a spec, the max data rate for a pair of signal lines is 3.4Gbps, which means the max data rate for a cable is 10.2Gbps. The next-gen spec includes plans to increase this max data transfer rate.

Enhanced network functions (2) will allow Ethernet data to be transferred over the same single HDMI cable. Some audio-visual (AV) equipment, such as liquid crystal display (LCD) TVs and Blu-ray Disc players, already come with both HDMI and Ethernet terminals. By adding Ethernet support to the HDMI spec, the hope is that the number of required terminals can be cut.

In addition to the above, HDMI Licensing is also expected to define new design guidelines for Consumer Electronics Control (CEC) functionality, to enhance home networking functions. Hopefully, this will facilitate cooperative operation with other equipment also equipped with CEC functions.

Enhanced audio (3) is support for 5.1-channel audio data via the same HDMI cable. Conventionally, output to AV receivers, bass speakers, etc, was through Sony Philips Digital InterFace (S/PDIF) cable. The new capability is intended to eliminate the need for the S/PDIF digital audio interface terminal.

By Tadashi Nezu, Nikkei Electronics Asia