The High-Definition Multi-media Interface (HDMI) is an industry-supported, uncompressed, all-digital audio/video interface with 5 Gbps of available bandwidth.

HDMI provides an interface between any compatible digital audio/video source, such as a set-top box, DVD player, and A/V receiver and a compatible digital audio and/or video monitor, such as a digital television (DTV).

The benefits of HDMI over traditional analog connections include:

• All-digital rendering of video without the losses associated with analog interfaces and their unnecessary digital-to-analog conversions.
• Lower cost: a single HDMI connection replaces 3 video connections for high definition video and 6 audio connections for high-resolution audio.
• Audio: HDMI supports multiple audio formats, from standard stereo to multi-channel surround-sound.
• Ease-of-use: HDMI combines video and multi-channel audio into a single cable, eliminating the cost, complexity, and confusion of multiple cables currently used in A/V systems.
• Intelligence: HDMI supports two-way communication between the video source (such as a DVD player) and the DTV, enabling new functionality.

HDMI has the capacity to support existing enhanced and high-definition video formats including 480p, 720p, 1080i, and even 1080p as well as standard definition formats such as NTSC or PAL.

The standard Type A HDMI connector has 19 pins and a higher resolution Type B also exists but is not yet in common use. Type B has 29 pins, allowing it to carry an expanded video channel for use with high-resolution displays. Type-B is designed to support resolutions higher than 1080i.

HDMI is backwards-compatible with the single-link Digital Visual Interface (DVI) commonly found on older HD televisions and set top devices through the use of a suitable adapter or cable, but the audio and remote control features of HDMI will not be available.

Additionally, without support for HDCP, the video quality and resolution may be downgraded by the player unit. Type B HDMI is similarly backwards-compatible with dual-link DVI.

In addition to carrying uncompressed video, HDMI is defined to carry 8-channels, of 192kHz, 24-bit uncompressed audio. HDMI can also carry compressed audio formats such as Dolby or DTS.

HDMI cables specifications are designed to use standard copper cable construction with certain levels of required performance and it is expected that HDMI cables can be expected to perform flawlessly in cables up to 15 meters in length.

The HDMI Founders include leading consumer electronics manufacturers Hitachi, Matsushita Electric Industrial (Panasonic), Philips, Sony, Thomson (RCA), Toshiba, and Silicon Image.

Learn more at the HDMI site http://www.hdmi.org/index.asp