High Definition Multimedia Interface (HDMI®) is a connection system used with digital audio and video. An HDMI® cable is a specially designed cable capable of transmitting uncompressed digital video and audio simultaneously. This type of cable is used to connect digital input sources to digital televisions, receivers and computer monitors.
An HDMI® cable.
To view high-definition video, Blu-Ray™ and eight-channel digital audio, an HDMI® compatible TV, source and cable are required. One HDMI® cable is a replacement for two analog cables, video and sound. HDMI supports any TV or PC video format, ranging from standard to high definition.
Used in most modern HDTVs, high definition video devices are connected via HDMI® cables.
The first HDMI® product was developed in 2002 to meet the requirements of a high quality digital audio and visual system. HDMI® specifications have been adopted by a wide variety of computer, television and electronics manufacturers. These standards were developed by an association of consumer electronics manufacturing firms, in cooperation with major film and music distribution companies.
There are two different types of HDMI® cable available for purchase, category one and two. The different categories only apply to HDMI® version 1.3 and above, which became available in October 2008. These cables are also backward compatible with HDMI®.
Category one HDMI® cables are labeled as standard cable and are ideal for transmitting 720p or 1080i audio and video signals. Category two cables are also called High Speed HDMI® cables and are capable of carrying 720p, 1080i and 1600p audio and video signals. Only Category Two cables are guaranteed to work with a cable length greater than 16 feet (4.8 meters).
When selecting an HDMI® cable, cable length is an important consideration. Due to signal attenuation, there is a limit to the length of an HDMI® cable before performance is affected. If the cable is too long, the digital signal will be too weak and the images on the screen will flicker.
Problems related to signal loss due to excessive cable length can be resolved by using HDMI® extenders, repeaters or equalizers. All these devices can be used to connect HDMI® cables to each other. With the use of these connecting devices, the cable length can be extended without any loss of signal strength.
The maximum possible length depends on the category of cable used. Category five and six cables can increase the total cable length by up to 164 feet (50 meters). If a fiber optic-based HDMI® extender is used, the total possible cable length increases to 328 feet (100 meters).
An HDMI cable is used to connect a digital receiver to a television.