Black Box Explains…HDMI
High-Defintion Multimedia Interface (HDMI) is the standard digital interface for HDTV. It was the first digital interface to combine uncompressed HD video up to eight channels of uncompressed digital audio, and intelligent format and command data in a single cable. It is now the de facto standard for consumer electronics and HD video, although it is beginning to face competition from the newer DisplayPort (DP) interface. In addition, HDMI also uses TMDS signaling, like DVI, and is backward compatible.
HDMI also supports multiple audio formats, from standard stereo to multichannel surround sound. In addition, the interface provides two-way communications between the video source and HDTV, enabling simple, remote, point-and-click configurations.
HDMI supports high-bandwidth digital content protection (HDCP), which prevents distribution and copying of digital audio and video content sent over HDMI cable. If a device between the source and the display supposrts HDMI but not HDCP, the transmission won't work if the content is copyright protected.
HDMI is backward compatible with DVI equipment because it uses transition-minimized differential signaling (TMDS). A DVI-to-HDMI adapter can be used without a loss of video quality to enable the connection. Because DVI only supports video signals, not audio, the DVI device simply ignores the extra audio data.
However, dual link is not common in HDMI. DVI displays usually also are not able to display HDCP protected and/or component encoded (YCbCr) HDMI signals.