Now that we have seen what HDMI cables carry, let’s look at standards and protocols through the last 10 years. The first iteration of HDMI was simply 1.0, as there were future versions as yet to be seen. It included a maximum bandwidth of 4.95 Gigabits per second. That supported 3.96 Gb of video information (1080P @ 60Hz/UXGA) as well as 8 channels of Audio (192 KHz, 24 bit), and some ancillary information. 1.1 added DVD audio. 1.2 added one bit audio, sRGB color support and full CEC features.
HDMI version 1.3 added the single link bandwidth of video to 10.2 Gb per second (more than twice the amount of bandwidth of ver. 1.0). It supported “Deep Color” which included up to 48 bit color resolution (i.e. the necessary extended bandwidth). It included items like “lip syncing” and other proprietary streaming algorithms as well. Version 1.4 included support of 2k and 4k video resolutions (at lower frame rates), as well as 3D and even more video resolutions (split into 2 separate versions of A & B).
HDMI version 2.0, (the most recent) also referred to some as version UHD (Ultra High Definition), supports 4K at 60 fps, and enhanced color and information development, while still using the same HDMI interface cabling.
The original distance limitation for HDMI was around 15 feet (Version 1.0). Wow. One of the factors that controlled this limitation was the use of proprietary cabling, for what was considered an acceptable HDMI interface. That is correct; in order for any device to be true “HDMI” compliant it needs to use acceptable HDMI connectors and cables. Unfortunately at that time, the manufacturers for these “acceptable” HDMI cables and interfaces were less than stellar.
A wire manufacturer (Belden) decided early on that they could improve upon that limitation, and they created a cable that was superior to the standard cabling (larger gauge, more robust) being used in the marketplace. Unfortunately, they also discovered for their new HDMI cables to be acceptable (approved) HDMI cables, they would need the same bandwidth limiting connectors that every other HDMI cable on the marketplace had. Even with those connectors, however; they were able to get significant distance gains over the current industry standard cables. To this date they are one of the longest single run cable manufacturers for HDMI, with runs as long as 100′, successfully, without signal loss or the use of HDMI extenders.
Jim Landis is a system designer for Matern Professional Engineering.