January 01, 2006 — Article
HDMI stands for High Defintion Multimedia Interface. Designed to take over from the universal connectors used for the transfer of analog audio video signals. The SCART connector is what you got with every TV as from 1981 and is now falling behind as it isn’t HD compatible.
In essence, SCART gathers together various common analog signal types into a single connector. Previously, each of these would have had their own socket, requiring numerous separate connections (and a “spaghetti” type mass of leads). In Europe, SCART is the most common method of connecting audio-visual equipment together, and has become the standard connector for such devices. Since there isn’t any chance for it to take on High-Definition standards there’s a definite need for a new interface.
The main difference between HDMI and SCART is the former is totally digital. That discards any chance of HDMI>SCART conversion. It’s a brand new start in the world of interfaces.
Devices are manufactured to adhere to various versions of the specification, where each version is given a number, such as 1.0 or 1.3. Each concurrent version of the specification uses the same cables, but increases the throughput and/or capabilities of what can be transmitted over the cable. For example, previously, the maximum pixel rate of the interface was 165Mpixels/second, sufficient for supporting 1080p at 60Hz or WUXGA (1920 x 1080), but HDMI 1.3 increased that to 340Mpixels/second, providing support beyond the highest resolution computer monitors available today. In any case, each version carries its very own specs but you needn’t worry too much about this detail but check out the section below.
HDMI supports any TV or PC video format, including standard, enhanced, or high-definition video, plus multi-channel digital audio on a single cable. It is independent of the various DTV standards such as ATSC, and DVB (-T,-S,-C), as these are encapsulations of the MPEG movie data streams, which are passed off to a decoder, and output as uncompressed video data on HDMI. HDMI encodes the video data into TDMS for transmission digitally over HDMI.
Supports standard and high defintion formats
There are five different versions of the HDMI connector today. The 1.0, 1.1, 1.2, 1.2a and 1.3 which each has its own minor specifications in terms of picture and sound quality. Indeed, if you’re going to be using DVD Audio, you should go for the *1.1 or 1.2 for SACD. The 1.3 version supports audio lossless formats such as * Dolby TrueHD and DTS-HD* as well as the corresponding new color norms.
Thanks to the HDCP, High Bandwidth Digital Content Protection, HDMI is a better protection for artistic content. But be aware that certain TVs, projectors or screens don’t support this format. They may not be able to display a signal coming from a protected source such as HD-DVD or Blu-ray players, the latest games consoles or high-definition numeric TV programs. This remains one of the most controversial aspects of HDMI.
The purchase of a TV or DVD player equipped with HDMI connectors is a sure bet today as it’s a true gage of quality and modernity. Incompatibility issues are becoming less and less frequent but do pay special attention to that aspect before you buy!