Everyone knows
that High Definition Multimedia Interface (HDMI) cables are the latest and
greatest connection for your high definition setup, but not all HDMI cables are
created equal. Since HDMI was originally
launched in late 2002, there have been seven different versions of the
specification - each one adding more features than the last. All HDMI connections
are compatible with previous versions, but you'll lose newer features when
connecting to an older HDMI port.
HDMI cables have
multiple uses; not only are they the best current method to send a video signal
to your television, but all HDMI cables have the ability to transmit sound in
the same cable. Newer versions of the standard support the full range of
lossless audio formats including Dolby TrueHD, DTS-HD MA, and PCM. Lossless
means the signal being sent is exactly the same as the original with no
compression. HDMI connections are even showing up on computer monitors and
video cards as a replacement for DVI.
 HDMI cables have
a bandwidth of 5Gbps or 10Gbps for the newest version, which is 10x to 20x the
bandwidth of a USB 2.0 cable. What makes the HDMI cables so versatile is that they
have more than enough bandwidth to send an uncompressed HD video signal, as
well as 7.1 audio channels. By not needing to compress the signal, there is no
quality loss in picture or sound.
Even though
there are currently seven different versions of the HDMI standard, consumers don't
really have to be concerned with the different versions until the 5th
iteration. HDMI 1.1 and 1.2 added support for DVD Audio discs and Super Audio
CDs. These niche music formats provide higher music quality than CD, but never
succeeded in becoming a mainstream replacement.
HDMI-CEC
HDMI 1.2a added Consumer
Electronic Control, which allows up to 10 devices connected by HDMI to "talk"
to each other. With future electronics, if you turn your receiver to DVD mode,
it would turn on the DVD player and set the TV to the correct input
automatically. HDMI-CEC would also allow a single remote to control multiple
devices without requiring a universal remote. This may become very useful down
the road but requires all your electronics to be CEC-enabled, many of which are
just starting to hit the market now. To make matters worse, every electronics
manufacturer calls CEC something different; Toshiba CE-Link, Panasonic EZ-Sync,
Sony Bravia Theater Sync, Samsung Anynet+ and LG SimpleLink.
Along came HDMI 1.3
When HDMI 1.3 first hit the market there was a lot of confusion about what the
benefits were and if it was really necessary. Bandwidth was increased from
5Gbps to 10Gbps, which although it was a huge improvement, it isn't really
needed for most current applications. To take advantage of the higher
bandwidth, a new "high speed" HDMI cable is needed. The increased bandwidth
helps to future proof HDMI cables as it now has a fast enough bitrate for
future 1440p displays, or video with high frame rates.
The other big
update with HDMI 1.3 is something that can be taken advantage of right away – providing
you have the equipment to handle it. HDMI 1.3 adds support for Dolby True HD
and DTS-HD Master Audio, which are both lossless audio codecs. To take
advantage of the new audio features you will need a newer receiver capable of
processing the signal and a 5.1 or 7.1 speaker setup. Other features added with
HDMI 1.3 adds Deep Color support, which increases the color depth to over 1
billion colors and Audio Syncing which helps to make sure the audio and video stay
timed correctly while the signals are processed.
HDMI 1.4 on the way?
Don't think that the HDMI engineers called it quits after seven versions. HDMI
1.4 is coming but not a lot of info has surfaced about it. You can expect
another bump in bandwidth, which will enable the capacity for more colors and
increase CEC functionality. More news on HDMI 1.4 will be posted as it gets
closer to release.
HDMI Versions:
1.0
- First
released in December 2002, the maximum bitrate stood at 4.9Gbps.
1.1 - HDMI 1.1
was released a year and a half later in May 2004. The only new feature added
was support for DVD Audio discs
1.2 - Version
1.2 adds support for Super Audio CD (SACD)
1.2a - HDMI 1.2a
adds in the specifications for Consumer Electronic Control (CEC).
1.3 - HDMI 1.3
is the biggest revision to the standard yet and adds a lot of new functionality.
This update added support for Dolby TrueHD and DTS-HD Master Audio. Bandwidth
was increased to 10Gbps. Other features added with HDMI 1.3 are Deep Color
Support and Audio Syncing. HDMI 1.3 is the first revision to the HDMI spec that
requires a new cable.
1.3a - Minor
updates that won't affect most consumers. More functionality for CEC devices
added.
1.3b - No new
consumer features added. Revision to HDMI compliance testing for manufacturers.
Resources:
Why HDMI? What you need to know before going digital
HDMI FAQ
Philip Davis talks about HDMI 1.4
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Re: All HDMIs Are Not Created Equal
