HDMI Part 1 - A Digital Interface Solution
There is a lot to talk about HDMI for one article, so I will cover the subject in 10 articles each addressing a different area of HDMI. This first article is about specs and versions. A special request made by Shane Sturgeon, our Magazine Chief Technologist & Co-Publisher, gave me the idea of covering other areas of HDMI not well covered by the press that often prompt Magazine readers to ask for help on the Tips list and the Forum.
HDMI, What is it for you?
Many people talk about HDMI as a cable, or as a spec, or as a chip, as a simplification of digital connectivity, as the end of HD content protected viewing for 10 million early adopters of HDTVs with only component analog connections, as a de-facto standard adopted by hundreds of manufacturers, as a connection that sometimes causes more problems than it resolves, etc. Well, it is all of the above; and depending on a person's agenda, he/she might be very unyielding about some of that list and entirely ignoring the others.
HDMI, How was it created?
On December 9, 2002, the seven founders of HDMI (High-Definition Multimedia Interface) announced the 1.0 specification of this connectivity standard, the enhanced, more robust form of DVI (see below). The seven founders are Hitachi, Matsushita, Philips, Silicon Image, Sony, Thomson, and Toshiba.
The standard supports HD uncompressed video, 8-channel digital audio (reportedly up to 192 KHz), and some control signals, all on a single cable (15 mm, 19 pin), while using less than half the available bandwidth of HDMI. HDMI was created with the same video capacity as DVI, or up to five Gbps of bandwidth, double what a HD signal would require, and is backward compatible with DVI by using an adapter, although that is for the video part only since DVI does not handle audio. With the newest version of HDMI announced in June of 2006, HDMI has doubled its bandwidth capacity to 10.2 Gbps.
HDMI is quickly replacing DVI and is being implemented already on many products, and is becoming the de-facto standard for transporting uncompressed signals over a cable.
HDCP (High-bandwidth Digital Content Protection)
This article is not intended to cover the details of HDCP.
The HDCP 1.0 specification was developed by Intel with contributions from Silicon Image in February 2000 to protect DVI outputs from being copied by providing a secure link between a video source and a display device.
HDCP offers authentication, encryption, and renewability. The Motion Picture Association of America (MPAA) endorsed HDCP as the standard for the secure transmission of HD signals over DVI, and is used on HDMI as well.
A Quick Summary of the Ancestor (DVI)
The DVI (Digital Visual Interface) 1.0 specification was introduced in April 1999 by the Digital Display Working Group integrated by Silicon Im...
RSS Feeds