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HDMI Simplified
What is HDMI ?
HDMI (High-Definition Multimedia Interface) is an uncompressed, all-digital audio/video format transmitted over a single cable. HDMI supports high definition video resolutions of up to 4096x2160 and 8 channels of digital audio. HDMI features include up to 340Mhz signal bandwidth, data speeds up to 10.2Gbps, Deep Color, Audio Return Channel and most recently option Ethernet capability among other features. HDMI supports two-way communication between the audio source (such as a DVD player) and the audio rendering device (such as an A/V receiver), enabling new functionality such as automatic configuration and one-touch play.
Version 1.4
The latest version of the HDMI specification is 1.4 and was released on May 28, 2009, with HDMI 1.4 products starting to hit shelves in late 2009/early 2010.
HDMI 1.4 increases the maximum resolution to 4K x 2K (3840x2160p at 24Hz/25Hz/30Hz and 4096x2160p at 24Hz, which is a resolution used with digital theaters); an HDMI Ethernet Channel, which allows for a 100 Mb/s Ethernet connection between the two HDMI connected devices; and introduces an Audio Return Channel, 3D Over HDMI, a new Micro HDMI Connector, expanded support for color spaces, and an Automotive Connection System. High Speed HDMI 1.3 cables can support all HDMI 1.4 features except for the HDMI Ethernet Channel.
HDMI Feature Comparison Chart
HDMI Version sRGB YCbCr 8 channel LPCM/192 kHz/24-bit audio capability 1080p video at full resolution Consumer Electronic Control (CEC) DVD Audio support xvYCC Ethernet Channel Audio Return Channel 4K x 2K/24 Resolution Support
Common Applications
HDMI is now the leading format in home theater is the primary connection on all high definition flat screen LCD and LED displays, DVD players, cable boxes and other video source and display products. HDMI is also appearing on some computers and video projectors. The recently introduced micro version will bring the format to PDA's and smart phones in the near future
How to choose the right HDMI Cable for your Application
HDMI Connection Types: First, there are presently four HDMI connector types. Type A and Type B are defined in the HDMI 1.0 specification, Type C is defined in the HDMI 1.3 specification, and Type D is defined in the HDMI 1.4 specification.
Type A: Nineteen pins, with bandwidth to support all SDTV, EDTV, and HDTV modes. Type A is electrically compatible with single-link DVI-D. This is the common HDMI connector most often used. Type B: This connector has 29 pins and can carry double the video bandwidth of Type A, for use with very high-resolution future displays such as (3840x2400). Type B is electrically compatible with dual-link DVI-D, but has not yet been used in any products. Type C: A Mini connector defined in the HDMI 1.3 specification, it is intended for portable devices. It is smaller than the Type A plug connector but has the same 19-pin configuration. The differences are that all positive signals of the differential pairs are swapped with their corresponding shield, the DDC/CEC Ground is assigned to pin 13 instead of pin 17, the CEC is assigned to pin 14 instead of pin 13, and the reserved pin is 17 instead of pin 14. The Type C Mini connector can be connected to a Type A connector using a Type A-to-Type C cable. Type D: A Micro connector defined in the HDMI 1.4 specification, it keeps the standard 19 pins of Types A and C but shrinks the connector size to something resembling a micro-USB connector. The Type D connector isPerformance Levels: Separating Fact From Fiction
While the signal itself is digital, it is still being transmitted over an analog medium so cable construction will play a role in your resolution output-especially over long distances. Keep in mind with HDMI cables, standard quality is enough for most uses-especially short lengths under 15 feet. Larger gauge cables with premium construction are well suited to longer length applications and professional environments where reliability and durability are critical. Construction will also have an impact on cost as more copper for larger gauges and more or preferred (and more effective) shielding methods will add to the purchase price. Look for well shielded cables, usually double or triple shielding with braided shielding over spiral or foil as a general rule. Also, be sure to get an ATC certified HDMI cable to ensure the cable meets the latest HDMI specifications (though be aware not all lengths are tested.).
That said, do not let anyone try to justify spending $50 or more for a short length HDMI cable as retail brands often do. You are just throwing your money away. Fancy all metal gold plated connectors and braided jackets are ploys to dramatically increase the price with zero performance benefit. On the other end of spectrum, use common sense and be very wary of anyone telling you that you can get professional or premium quality for $1.50 either. That bargain won't seem as attractive when you have to endure the additional aggravation and expense of downtime and a second purchase to replace a poorly made cable from some internet importer selling cheap knock-offs from China. No matter whom you buy from, be sure to buy from a reputable choice.
Standard HDMI Cable
Standard HDMI cables are usually 30 or 28 gauge, sometimes with a ferrite core to supplement the lower-cost shielding method. These are perfectly fine for general purpose use and short runs usually 15ft or less.
Premium Professional Grade HDMI Cable
Image Premium professional HDMI cables are typically constructed of 28 gauge or larger construction and feature double shielding or better to provide a 90% or higher shielding coverage which helps protect against EMI and RFI interference. Professional HDMI cables will many times also utilize a heavier mold construction for increased durability-important for those installing cables and using them in more demanding environments.
Super Premium HDMI Cable
Image Super Premium HDMI cables usually feature a larger 24 or 22 gauge gauge construction and will often times feature triple shielding. These are very well suited for heavy-duty applications such as system integration and staging environments. These are the cable of choice for longer runs above 25ft.
Related Products: HDMI Cables, HDMI Splitters, HDMI Extenders, HDMI Adapters, DisplayPort Cables, DVI Cables
HDMI Pin-Out HDMI Female Receptacle
Pin 1 TMDS Data2+ Pin 2 TMDS Data2 Shield Pin 3 TMDS Data2- Pin 4 TMDS Data1+ Pin 5 TMDS Data1 Shield Pin 6 TMDS Data1- Pin 7 TMDS Data0+ Pin 8 TMDS Data0 Shield Pin 9 TMDS Data0- Pin 10 TMDS Clock+ Pin 11 TMDS Clock Shield Pin 12 TMDS Clock- Pin 13 CEC Pin 14 Reserved (N.C. on device) Pin 15 SCL (I²C Serial Clock for DDC) Pin 16 SDA (I²C Serial Data Line for DDC) Pin 17 DDC/CEC Ground Pin 18 +5 V Power (max 50 mA) Pin 19 Hot Plug Detect What functionality was added to each version of HDMI?
The following provides an overview of major functionality added to each version of HDMI:
HDMI 1.1:
- Support for DVD Audio.
HDMI 1.2:
- Adds features and capabilities that increase HDMI's appeal for use in both the CE and PC industries. Specifically, the features and modifications for HDMI 1.2 include: Support for One Bit Audio format, such as SuperAudio CD's DSD (Direct Stream Digital), changes to offer better support for current and future PCs with HDMI outputs, including: availability of the widely-used HDMI Type A connector for PC sources and displays with full support for PC video formats, ability for PC sources to use their native RGB color space while retaining the option to support the YCbCr CE color space, requirement for HDMI 1.2 and later displays to support future low-voltage (i.e., AC-coupled) sources, such as those based on PCI Express I/O technology.
HDMI 1.2a:
- Consumer Electronic Control (CEC) features and command sets and CEC compliance tests are now fully specified.
- Creation of version 1.2a of the HDMI Compliance Test Specification (CTS), which includes a CEC Supplement. HDMI CTS 1.2a has been updated for technical consistency with HDMI Specification 1.2a as well as to the recently released HDMI Specification 1.2.
- Significantly, CTS 1.2a contains additional cable and connector testing and Authorized Testing Center (ATC) submission requirements. Specifically, under CTS 1.2a, the Adopter shall submit for testing to the ATC any new HDMI cable whose length exceeds previously tested cables.
- Additionally, HDMI Licensing, LLC will maintain a list of approved connectors. For a device to pass CTS 1.2a testing at an ATC, all connectors on such device must appear on the approved connector list. To add a connector to this list, the vendor must submit to the ATC or HDMI Licensing, LLC full and passing testing results.
HDMI 1.3:
- Higher speed: HDMI 1.3 increases its single-link bandwidth to 340 MHz or 10.2 Gbps (for Cat 2) to support the demands of future HD display devices, such as higher resolutions, Deep Color and high frame rates. In addition, built into the HDMI 1.3 specification is the technical foundation that will let future versions of HDMI reach significantly higher speeds.
- Deep Color: HDMI 1.3 supports 10-bit, 12-bit and 16-bit (RGB or YCbCr) color depths, up from the 8-bit depths in previous versions of the HDMI specification, for stunning rendering of over one billion colors in unprecedented detail.
- Broader color space: HDMI 1.3 adds support for "x.v.Color™" (which is the consumer name describing the IEC 61966-2-4 xvYCC color standard), which removes current color space limitations and enables the display of any color viewable by the human eye.
- New mini connector: With small portable devices such as HD camcorders and still cameras demanding seamless connectivity to HDTVs, HDMI 1.3 offers a new, smaller form factor connector option.
- Lip Sync: Because consumer electronics devices are using increasingly complex digital signal processing to enhance the clarity and detail of the content, synchronization of video and audio in user devices has become a greater challenge and could potentially require complex end-user adjustments. HDMI 1.3 incorporates automatic audio synching capabilities that allows devices to perform this synchronization automatically with total accuracy.
- New HD lossless audio formats: In addition to HDMI's current ability to support high-bandwidth uncompressed digital audio and all currently-available compressed formats (such as Dolby® Digital and DTS®), HDMI 1.3 adds additional support for new lossless compressed digital audio formats Dolby TrueHD and DTS-HD Master Audio™.
HDMI 1.4:
- HDMI Ethernet Channel
The HDMI 1.4 specification adds a data channel to the HDMI connection, enabling high-speed, bi-directional communication. Connected devices that include this feature can send and receive data via 100 Mb/sec Ethernet, making them instantly ready for any IP-based application. The HDMI Ethernet Channel allows internet-enabled HDMI devices to share an internet connection via the HDMI link, with no need for a separate Ethernet cable. It also provides the connection platform that will allow HDMI-enabled components to share content between devices.- Audio Return Channel
The new specification adds an audio channel that will reduce the number of cables required to deliver audio "upstream" from a TV to an A/V receiver for processing and playback. In cases where a TV features an internal content source, such as a built-in tuner or DVD player, the Audio Return Channel allows the TV to send audio data upstream to the A/V receiver via the HDMI cable, eliminating the need for an extra cable.- 3D Over HDMI
The 1.4 version of the specification defines common 3D formats and resolutions for HDMI-enabled devices, enabling 3D gaming and other 3D video applications. The specification standardizes the input/output portion of the home 3D system, facilitating 3D resolutions up to dual-stream 1080p.- 4K x 2K Resolution Support
The new specification enables HDMI devices to support extremely high HD resolutions, effectively four times the resolution of a 1080p device. Support for 4K x 2K allows the HDMI interface to transmit digital content at the same resolution as the state-of-the-art Digital Cinema systems used in many movie theaters.- Expanded Support For Color Spaces
HDMI now supports color spaces designed specifically for digital still cameras, enabling more accurate color rendering when viewing digital photos. By supporting sYCC601, Adobe®RGB, and Adobe®YCC601, HDMI display devices are capable of displaying more accurate, life-like colors when connected to a digital camera.- HDMI Micro Connector (Type D)
The HDMI Micro Connector is a significantly smaller 19-pin HDMI connector supporting up to 1080p resolutions for portable devices such as cell phones, portable media players, and digital cameras. This new connector is approximately 50% smaller than the size of the existing HDMI Mini connector.- Automotive Connection System (Type E)
The Automotive Connection System is a cabling specification designed to be used for in-vehicle HD content distribution. The HDMI 1.4 specification provides a solution designed to meet the rigors and environmental issues commonly found in automobiles, such as heat, vibration and noise. Using the Automotive Connection System, car manufacturers now have a viable solution for HD distribution within a vehicle.
Are all of the new HDMI versions backward compatible with previous versions?
Yes, all HDMI versions are fully backward compatible with all previous versions.
What version of HDMI does a consumer need to view 1080p content?
HDMI has always supported 1080p resolution, starting from version 1.0 in 2002. However, as with many functions that HDMI enables (such as DVD-Audio and SACD), it is up to the manufacturer to choose whether to implement 1080p in the device. Some TV and device manufacturers have chosen not to implement 1080p in their products because 1080p content has not been widely available, and because changing the internal electronics of the device to support 1080p would increase cost.
Viewing 1080p resolution requires at minimum that the HDTV have a display supporting the 1080p pixel resolution. Today, many HDTVs use display technologies (such as PDP, LCD, and microdisplay screens) designed for 720p pixel resolution. In the past, some 1080p HDTVs supported only 720p or 1080i on the HDMI input, then perform video processing to up-convert the 720p/1080i signal to 1080p. This is now changing, as 1080p content is becoming increasingly available, and HDTVs fully supporting 1080p in the display and HDMI electronics became more popular in the market in early 2006. True 1080p HDTVs are currently offered in the market by a variety of TV manufacturers.
Do you need a new version of HDMI to play Blu-ray and HD-DVD content in high definition?
All versions of the HDMI specification support the ability to watch HD-DVD / Blu-ray content in high definition up to 1080p resolution. However, there may be non-HDMI reasons that prevent some devices from accessing content in high definition, including lack of HDCP support.
Are HDMI 1.0, 1.1 and 1.2 compatible with the next generation videogame consoles implementing 1080p and HDMI's new Deep Color capability?
The HDMI specification has supported 1080p content since version 1.0, and each new revision of the HDMI specification is fully backward compatible with previous revisions.
In June 2006, the HDMI Founders announced HDMI 1.3 and new capabilities to support Deep Color (up to 16-bit color RGB color) and new lossless audio formats (such as Dolby TrueHD and DTS-HD Master Audio). PCs and video game consoles in particular are expected to be capable of delivering content that takes advantage of HDMI's latest capabilities. When such sources are interfaced to older HDMI HDTVs, the source should automatically select the highest quality video and audio performance supported by the HDTV.Can HDMI cables contribute to devices not working properly together?
The vast majority of image quality or interoperability issues with HDMI devices are related to the software (firmware) used for device communication and content protection, and have nothing to do with the HDMI cable. In particular, these issues are often caused by the software related to HDCP handshaking, or from devices improperly handling the device capability information read through HDMI (e.g. the device has an incorrect EDID, or an inability to properly read an EDID). It is fairly uncommon for the cable to be the cause of HDMI compatibility problems. In fact, the robustness of the HDMI specification has been verified by the fact that we have not found a compliant HDMI cable that is the root cause of HDMI playback issues with compliant devices.What is the most common compatibility problem among devices with HDMI connections?
The most common compatibility problems have to do with HDCP. Probably the most common failure is the lack of an HDCP repeater function or failure to perform the authentication reliably in all types of usage scenarios. We are increasingly seeing HDCP becoming less and less of a problem as manufacturers iron out the kinks in later generation devices and as cable operators download upgraded firmware to their set-top boxes. In addition, as of November, 2006, the HDMI Founders required all HDMI devices implementing HDCP to undergo a new mandatory compliance testing program of the HDCP functions. This is based on the HDCP Compliance Test Specification.What is HDCP?
Some cable TV set-top boxes with HDMI outputs don't deliver a picture to displays with HDMI inputs. What is the problem, and is there a solution?
HDCP stands for High Definition Content Protocol and is a copy protection scheme to eliminate the possibility of capturing content sent digitally from the source to the display. The format is designed by Intel with help of Silicon Image, the company that distributes the chips to enable the scheme, HDCP enables a secure connection between devices such as DVD players and HDTV set-top-boxes using an authentication and key exchange procedure before video and audio is presented. If your video source sends DVI or HDMI™ signal that is HDCP encrypted, your display must also be HDCP compliant. Otherwise, the signal will result in what we call "sparkles" or snow. All PureLink DVI and HDMI Switching Systems are HDCP compliant. Be sure to check HDCP compliance when you purchase any AV equipment.
In some cases, the set-top box software does not activate or support the HDMI port. In other cases, cable TV set-top boxes don't work correctly when used in conjunction with an A/V receiver (but will typically function correctly when connected directly to a TV or monitor). Investigation of some of these devices reveals that this is caused by an error in the way these set-top box devices implement HDCP. Specifically, some of those boxes do not support "HDCP repeaters" (devices that pass along the signal to another device) such as an A/V receiver or switch. We believe that this may be a problem in the initial versions of these products, and in some cases there is new firmware available that fixes this issue in HDMI (newer versions may already have this fix). We have been actively working with manufacturers to resolve these problems. We suggest that users contact their cable operator and request the new software to address these issues. As noted above, cable operators are increasingly downloading the available firmware upgrades required to fix this error.
If an HDMI accessory device (i.e. switch box, cable booster) does not have a dedicated power supply, is it still compliant and will it work?
An HDMI device that has active electronics should have a provision for external power in order to be compliant (e.g. a receptacle to allow the use of a standard power adapter, sometimes called a power "brick"). Here we are drawing a distinction between "active" devices that actually have some powered electronics, and "passive" devices, such as some switches (more on those later).
Some active devices, such as actively powered HDMI cables or in-line signal extender boxes, will by default attempt to power their electronics by taking power from the 5V line (+5V power) available on the HDMI connector. The HDMI specification requires all source devices to provide at least 55mA (milliamps) on the 5V line for the purpose of reading the EDID of a display. While 55mA is not enough current to operate most HDMI accessory devices (which typically require about 100 to 150mA), most source devices on the market today provide significantly more current on the 5V line than the HDMI specification requires. As a result, the vast majority of accessory devices can operate when interfaced with a source device that provides more than the required current (i.e. over 100-150mA) on the 5V line. However, manufacturers should provide a provision for their powered HDMI accessory devices to obtain external power, and consumers are encouraged to look for this external power provision when purchasing such products.
Looking to the future, not all HDMI devices may provide this much power over the 5V line. For example, as HDMI expands into more and more portable applications (cameras, camcorders, laptops, etc.), power consumption is often much more of an issue, and such devices may not power the 5V line with the > 100mA required by such "active" devices. Again, consumers should consider ensuring that their active HDMI accessory device purchases have a provision for external power for this reason.
What version of HDMI does a consumer need to view 1080p content?
HDMI has always supported 1080p resolution, starting from version 1.0 in 2002. However, as with many functions that HDMI enables (such as DVD-Audio and SACD), it is up to the manufacturer to choose whether to implement 1080p in the device. Some TV and device manufacturers have chosen not to implement 1080p in their products because 1080p content has not been widely available, and because changing the internal electronics of the device to support 1080p would increase cost.
Viewing 1080p resolution requires at minimum that the HDTV have a display supporting the 1080p pixel resolution. Today, many HDTVs use display technologies (such as PDP, LCD, and microdisplay screens) designed for 720p pixel resolution. In the past, some 1080p HDTVs supported only 720p or 1080i on the HDMI input, then perform video processing to up-convert the 720p/1080i signal to 1080p. This is now changing, as 1080p content is becoming increasingly available, and HDTVs fully supporting 1080p in the display and HDMI electronics became more popular in the market in early 2006. True 1080p HDTVs are currently offered in the market by a variety of TV manufacturers.
Do you need a new version of HDMI to play Blu-ray and HD-DVD content in high definition?
All versions of the HDMI specification support the ability to watch HD-DVD / Blu-ray content in high definition up to 1080p resolution. However, there may be non-HDMI reasons that prevent some devices from accessing content in high definition, including lack of HDCP support.
Are HDMI 1.0, 1.1 and 1.2 compatible with the next generation videogame consoles implementing 1080p and HDMI's new Deep Color capability?
The HDMI specification has supported 1080p content since version 1.0, and each new revision of the HDMI specification is fully backward compatible with previous revisions.
In June 2006, the HDMI Founders announced HDMI 1.3 and new capabilities to support Deep Color (up to 16-bit color RGB color) and new lossless audio formats (such as Dolby TrueHD and DTS-HD Master Audio). PCs and video game consoles in particular are expected to be capable of delivering content that takes advantage of HDMI's latest capabilities. When such sources are interfaced to older HDMI HDTVs, the source should automatically select the highest quality video and audio performance supported by the HDTV.
Does HDMI support Dolby 5.1 audio and high-resolution audio formats?
Yes. From the start, HDMI was defined to carry 8-channels, of 192kHz, 24-bit uncompressed audio, which exceeds all current consumer media formats. In addition, HDMI can carry any flavor of compressed audio format such as Dolby or DTS. (Such compressed formats are the only multi-channel or high-resolution audio formats that can be carried across the older S/PDIF or AES/EBU interfaces.) Additionally, most existing HDMI sources can output any compressed stream, and the newer sources can output uncompressed 6-channel, 96kHz audio from a DVD-Audio disk. There are A/V receivers on the market that can accept and process the 6- or 8-channel audio from HDMI.
Does HDMI support Dolby Digital, DTS, and high-resolution audio formats?
Yes. From the start, HDMI was defined to carry 8-channels of 192kHz, 24-bit uncompressed audio, which exceeds all current consumer media formats. In addition, HDMI can carry any currently available flavor of compressed audio format such as Dolby (including Dolby Digital EX 7.1, Dolby Digital Plus 7.1, Dolby TrueHD) or DTS (including DTS-ES 6.1 and DTS-HD Master Audio). Such compressed formats are the only multi-channel or high-resolution audio formats that can be carried across the older S/PDIF or AES/EBU interfaces. HDMI 1.3 adds additional support for new lossless digital surround audio formats Dolby TrueHD and DTS-HD Master Audio. Additionally, most existing HDMI sources can output any compressed stream, and the newer sources can output uncompressed 6-channel, 96kHz audio from a DVD-Audio disk. There are A/V receivers on the market that can accept and process the 6- or 8-channel audio over HDMI.
Is HDMI backward compatible with DVI (Digital Visual Interface)?
Yes, HDMI is fully backward compatible with DVI compliant devices. HDMI DTVs will display video received from existing DVI-equipped products, and DVI-equipped TVs will display video from HDMI sources. However, some older PCs with DVI are designed only to support computer monitors, not televisions. Consumers buying a PC with DVI should make sure that it specifically includes support for television formats and not just computer monitors.
Also, consumers may want to confirm that the DVI interface supports High-bandwidth Digital Content Protection (HDCP), as content that requires HDCP copy protection will require that both the HDMI and DVI devices support HDCP to properly view the video content.
*Source www.hdmi.org
