3D HDTV and HDMI Explained
(February 22, 2010) The Internet is replete with bad information regarding 3D ready Blu-ray player/ surround sound receiver/ Full HD 3D TV (FHD3D) HDMI connectivity. Unfortunately, HD Guru is not immune from this: we recently passed along misinformation received in an email from an official Blu-ray Disc Association (BDA) spokesperson, for which we apologize.
To set the record straight HD Guru recently met with Waheed Rasheed, director of product marketing for Silicon Image, the company that created HDMI and its related standards. He provided us with clear and precise information regarding the recently published HDMI standards as they relate to 3D products.
Full HD 3D
Transmitting uncompressed Full High Definition 3D (FHD3D) signals (defined as 1920 x 1080 resolution for both the left and right eye [each frame]) requires connecting a 3D Blu-ray player to a FHD3D TV using a suitable HDMI cable. The FHD3D signal’s bit rate is 6.75 Gbps (gigabits per second). The HDMI 1.4 standard’s maximum bit rate of 10.2Gbps is identical to that of the older HDMI 1.3 standard.
The 1920 x 2205 pixel at 24Hz (see drawing above) FHD3D signal differs from any previous HD or 3D signal. 1920 is the number of active pixels across each frame while 2205 pixels is the vertical resolution of two Full HD frames plus 45 pixels of active blanking separating the FHD left and right frames.
As the drawing illustrates, the signal places the two frames in a configuration known as “over/under”. This is the first and currently only FHD3D TV standard signal and because it is totally new, no non-FHD3D display can accept it.
This is important, as some consumer electronics writers speculate incorrectly that a modification will allow legacy 120Hz and 240Hz LCD displays to handle Blu-ray FHD3D content.
That said, Mitsubishi’s 2007, 2008 and 2009 legacy rear projection sets can be adapted to play these new FHD3D signals. Mitsubishi announced and demonstrated at the 2010 CES a converter box that down-converts the Blu-ray FHD3D HDMI signal (albeit at half resolution [960 x1080] for each eye). The converter box is due to arrive around the same time the first 3D capable Blu-ray players ship this spring.
The new HDMI 1.4 standard also permits another “over/under” 3D configuration at the lower 720p HD resolution (1280×720) at either 60Hz or 50 Hz Blu-ray player output.
All 3D Blu-ray players output FHD3D movies at 24 fps. Both LED LCD and CCFL backlit FH3D HDTVs internally convert the signal to sequential display (alternating left and right frames) at 240Hz (synchronizing with shutter glasses that provide 120 views per second for left and right eyes [120+120 =240]. All announced FHD3D plasma displays internally convert the 3D Blu-ray movie signals from “over/under” to frame sequential at 120 Hz for 60 views per second for each eye.
Surround Sound Receivers
Unfortunately, your current HDMI equipped surround sound receiver will not pass the new FHD3D signal and no upgrades are possible according to both Sony and Denon. Why? A system called EDID (Extended Display Identification Data) currently handles communications between your TV, receiver and source components and it works fine. However, when your new 3D television communicates that it is an FHD3D television, the receiver will not understand because the 3D ID was not part of the standard when your receiver was designed. The receiver will shut off the HDMI signal and your new 3D TV screen will go black.
Your only solution will be to replace your receiver with a new one that’s 3D compatible or use one of a number of available “work arounds”. You can still use your current HDMI receiver with Panasonic’s upcoming 3D Blu-ray player because it includes a separate “audio” only HDMI output. Connect the video HDMI directly to your 3D set and the audio HDMI to your receiver to decode Dolby TruHD or DTS lossless codecs. No other manufacturer has announced this feature. You can also use coax or optical digital from the 3D Blu-ray player but you won’t get lossless audio and you’ll still have to connect the 3D Blu-ray player directly to the 3D HDTV to see the picture.
3D HDMI Cables
Will your existing 1.3 HDMI cables handle the FHD3D signal or will you have to replace them? The only way to really know is to connect it and see if they work. Some will, some won’t. If the cable can handle the 6.75 Gbps FHD3D data rate, it probably will.
There are two types of legacy 1.3 HDMI cables: Category 1 and Category 2. The former must be able to handle at least 2.25 Gbps signals, meaning it may not be able to handle FHD3D signal . Category 2 HDMI 1.3 cables handle signals up to 10.2 Gbps. These will certainly work.
The HDMI 1.4 standard has optional features for both TV and source component makers, including an audio return function and Ethernet connectivity (which allows one Ethernet signal to be carried to other connected components via HDMI if the maker includes this 1.4 feature).
To streamline HDMI cable selection Silicon Image dispensed with the old numerical system and replaced it with the following categories (source: hdmi.org website):
Standard HDMI Cable
The Standard HDMI cable is designed to handle most home applications, and is tested to reliably transmit 1080i or 720p video the HD resolutions that are commonly associated with cable and satellite television, digital broadcast HD, and upscaling DVD players.
Standard HDMI Cable with Ethernet
This cable type offers the same baseline performance as the Standard HDMI Cable shown above (720p or 1080i video resolution), plus an additional, dedicated data channel, known as the HDMI Ethernet Channel, for device networking. HDMI Ethernet Channel functionality is only available if both linked devices are HDMI Ethernet Channel-enabled.
Automotive HDMI Cable
Designed for internal cabling of vehicles equipped with onboard HD video systems. Tested to a more robust performance standard, and capable of withstanding the unique stresses of the motoring environment such as vibration and temperature extremes.
High Speed HDMI Cable
The High Speed HDMI cable is designed and tested to handle video resolutions of 1080p and beyond, including advanced display technologies such as 4K, 3D, and Deep Color. If you are using any of these technologies, or if you are connecting your 1080p display to a 1080p content source, such as a Blu-ray Disc player, this is the recommended cable.
High Speed HDMI Cable with Ethernet
This cable type offers the same baseline performance as the High Speed HDMI Cable shown above (1080p video resolution and beyond), plus an additional, dedicated data channel, known as the HDMI Ethernet Channel, for device networking. HDMI Ethernet Channel functionality is only available if both linked devices are HDMI Ethernet Channel-enabled.
Edited by Michael Fremer
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