HDMI is the High-Definition Multimedia Interface used as a standard for HDTV televisions and home theater systems. HDMI carries a 5 Gbps bandwidth through at least 19 wires placed together as a cable. This makes the signal extremely reliable because the bandwidth used doubles what is actually needed for multi-channel video and audio.
HDMI is the technology used to replace component video, S-Video and composite video. It is an uncompressed, completely digital signal unlike the analog sign of its predecessors. HDMI doesn’t use analog conversion so the picture quality isn’t distorted like the other types of interfaces.
There are two different types of HDMI; Type A and Type B. Type A has 19 wires and Type B currently has 29. Type B was developed for, and is currently being used by, the motion picture industry. It offers the highest quality of digital signals. Unlike the cables previously used, the HDMI cables are capable of surround sound from eight different digital audio channels.
HDMI is compatible with standard and enhanced video formats, HD and DVI. Using a high-end card with DVI ports and a DVI/HDMI cable, HDMI can easily be connected to a DVI connector. As long as the cables are within their 5-meter limitations, you will never experience any type of signal distortion or unreliability.
More and more HDTVs are being shipped with multiple HDMI interfaces. Starting in 2005, most of them had at least one; which was soon deemed as not as reliable as multiple interfaces. Two or three are now being used to support multiple devices that may be connected.
The benefits of HDMI greatly outnumber that of analog connections. Not only are the image quality much greater, but the audio is also to the highest degree of superiority. Since HDMI only uses one cable it eliminates the clutter that multiple cables cause. HDMI is also highly versatile and is even able to auto-correct itself. Even with all of this, HDMI is very low-cost solution.
HDMI supports 720p, 1080i, and 1080p HD video formats as well as the standard formats NTSC and PAL. In audio, it supports stereo and multi-channel surround sound.