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HDMI | What is HDMI (High Definition Multimedia Interface)

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What is HDMI (High Definition Multimedia Interface)

HDMI is the modern standard interface for audio/video (A/V) connectivity, which stands for High-Definition Multimedia Interface. Generally, it is a connector that is used for connecting your audio-video devices together. The first HDMI equipment went under production in the early 21st century in 2003. The below picture represents how the HDMI cable looks.

What is HDMI

HDMI technology is now widely used in consumer devices, including the devices such as DVD player, HDTV, Blu-ray player, cable boxes, video game consoles, audio receivers, and Projector use the HDMI technology. For audio and video data, other types of A/V connections need separate cables, whereas a single HDMI cable carries an uncompressed digital signal that is sufficient for HD audio and video presentations. For instance, for audio and video, an analog component cable connection requires a total of five cables, two for audio and three for video. On the other hand, a single HDMI cable has the ability to transmit the same information digitally.

As compared to analog cables, HDMI cables are signal noise and less prone to interference, as it is a digital connection. Also, HDMI performs conversions from the digital-to-analog and analog-to-digital, whereas most of the components like digital cable boxes and DVD players process information digitally. Therefore, as compared to other types of connections, HDMI typically produces the best quality sound and picture. HDMI cables cost more to manufacture; therefore, they are often more expensive comparing analog cables. But HDMI cable offers the benefit in terms of working, as a single HDMI cable can work of multiple analog cables.

The single all-purpose connection provides the benefit in terms of easily connecting and disconnecting devices with the help of simplifying its setup. It also has the ability to support digital commands that make it capable of allowing devices to communicate with each other. For instance, if a TV is connected through HDMI to a receiver and when the TV is turned on and off, the receiver can be turned on and off by the TV. And, you can also configure the receiver settings visually with the help of using your TV as an interface if your TV is connected through a modern HDMI receiver.

Furthermore, HDMI connectors are available with five different types (A through E) with different specifications and several numbers of pins. The standards have been developed for HDMI by manufacturers, including support for minimum audio capacity and sRGB color space. Additionally, comparing analog technologies, HDMI enables greater bandwidth and also supports encryption techniques.

Different lengths of HDMI cables?

There are various lengths available of HDMI cable in the market. Its length can run from one foot up to 50 feet; however, it is not recommending to purchase over 25-foot cable. Because users may face a problem of signal degradation or signal loss if they buy more than a 25-foot cable.

A history of HDMI

In the early 16 April 2002, the founders of the technology first began to work on the HDMI first version, HDMI 1.0. This idea was to create a new standard at that time that would be backward compatible with a video-only standard, called DVI. At the time, a video-only standard could be found on many monitors.

Those founders who were working on the versions of HDMI, were actually not new in their field. Instead, they were a group of international companies, and for the next few decades of video and audio transfer, they wanted to develop a new standard. Although RCA, Sony, Panasonic, Philips, Toshiba, and more companies were included in the original founders of HDMI, like Disney, Universal, Warner Bros., and more tech also provided support of content.

Other goals for HDMI were also. For instance, the founders wanted to make it easier to use for consumers by making it relatively small and adding biter audio compatibility. In 2003, Silicon Image opened the first HDMI Authorized Testing Center on 23 June 2003, after developing the standard. On 1 May 2004, in Osaka, this standard was followed by another center in Japan. In the same year, 2004, after a few years of developing the standard for the first time, a large number of 5 million HDMI devices were sold. In Caen, France, on 25 May 2005, Philips opened the first ATC in Europe.

In Shenzhen, on 21 November 2005, Silicon opened the first ATC in China. In Bangalore, on 12 June 2008, Philips opened the first ATC in India. In 2004, 5 million HDMI devices were sold, according to In-Stat. In 2005, 17.4 million, 63 million in 2006, and in 2007, 143 million. In 2007, approx. 90% of digital televisions included HDMI, according to In-Stat, and HDMI has become the de facto standard for HDTVs. In 2008, 229 million HDMI devices were sold, estimated by In-Stat.

On 8 April 2008, over 850 PC companies and consumer electronics were adoped by HDMI specification. Over 600 million HDMI devices had installed the HDMI on 7 January 2009, which was announced by HDMI Licensing, LLC. In 2009, 394 million HDMI devices would sell, according to the estimation of In-Stat. It is also estimated by In-Stat that at least one HDMI input would be included in all the digital televisions by the end of 2009. In the Home Theater category, PC Magazine was awarded a Technical Excellence Award for an “innovation in 2008, whose gave too much impact to the world.

HDMI founders, to create an open organization, established the HDMI Forum on 25 October 2011, through which companies that were interested made capable of working in the development of the HDMI specification. Although in the HDMI Forum, there is no limit of allowed companies, they need to pay US$15,000 as an annual fee, and companies who serve on the Board of Directors need to pay an additional annual fee of $5,000.

Also, there were over 1,100 HDMI adapters, this was announced by LLC on the same day HDMI Licensing. And, since the launch of the HDMI standard, over 2 billion HDMI-enabled products had shipped.

Furthermore, over 1,300 HDMI adopters were there, announced by HDMI Licensing, LLC on 8 January 2013, and since the launch of the HDMI standard more than 3 billion HDMI devices had shipped.

What Audio Formats Does HDMI Support?

The minimum standard of uncompressed stereo LPCM audio must be supported by any device with HDMI. Any other formats are optional; hence, the audio types will be limited from available to you on the basis of using hardware by you. The 8-channels of compressed and uncompressed audio are allowed by the HDMI specification at 1-bit, 16, 20, and 24bit; at sample rates of 32kHz, 44, 48, 88.2, 96, 176.4, and 192 kHz. Some formats are given below:

  • DTS 96/24
  • DTS-HD High Resolution
  • DTS-HD Master Audio
  • LPCM (2-ch to 8-ch)
  • Dolby Digital
  • DTS:X
  • DVD-A
  • DSD
  • Dolby Digital Plus
  • Dolby TrueHD
  • Dolby Atmos
  • DTS
  • DTS-ES
  • DTS Express

If your hardware would support, various other formats will also available for you, such as ALAC, WAV, and FLAC. Also, you can check the certification for that device if you really need something different. HDMI will not limit you, but the design of your device can limit you.

What Video Formats Does HDMI Support?

HDMI has the ability to support more video formats, includes 720p, 1080p, 1440p, 4k, and 8k. For using that video resolution, your hardware must have the capability of supporting that HDMI standard.

There is a need to remember a thing; some devices may still come within the limit as designed by manufacturers. They may also design the devices in such a way that may add support for a format, which is not in the HDMI specification.

HDMI Version Video Formats
HDMI 1.0-1.1
HDMI 1.2-1.2a
HDMI 1.3-1.4b
HDMI 2.0-2.0b
HDMI 2.1

When uses HDMI?

Generally, HDMI is the best connection when you are going to use to link most modern audio/video devices together. Older devices may not have an HDMI port, but most of the devices that made in recent years have this connection. For sending the video and the audio signals, it requires one cable; sometimes, you will be unable to use HDMI to attach all your devices because of some situations. For case, one one device, you may use a DVI connector and an HDMI connector on another. With the help of DVI to HDMI adapters, there is an option to change one end of a cable from one connector type to another. As represented in the below image:

What is HDMI

Therefore, a normal HDMI cable can be used, you only need to plug the adapter into the DVI connection. But remembr that through this, you will only be able to transmit the picture. In contrast to HDMI, DVI only has the ability to support video signals. In this example, like coaxial or optical audio, you will only be able to send the audio. All HDMI devices have the capability of supporting HDCP.

How can we choose the best HDMI Cable?

When you are going to purchase a new cable, there are too many variations of the cable for selecting among them. You may feel impossible to select the best HDMI cable because there are different prices, different specifications, different colors, different materials, and different lengths of the cable. But you can concentrate on the points that are given below. These important objects may help you out to find the best HDMI cable.

Length: Determine the length of the cable is a very important factor. You must take few times to consider the cable length; first think where you want to run cable and how far that will be. As a rule of thumb, the signal can be weak through a very long cable, and it might be hard to run the cable in a limited area. Therefore, select the length of the cable according to your requirements.

Color: It depends upon the users which colors of cable they want to buy as it is not sure that color will make much difference to the sound and picture. Some people choose an unobtrusive color that can help easily camouflaged among their other equipment. However, the availability of black color is much high.

Price: The HDMI cable is available at different-different prices on the market. If you like, you can get a really expensive one. However, as compared to a decent quality budget cable, it will not perform additional. Twisted Veins HDMI cables are popular if you want a braided model.

Specifications: In modern times, category 2 ‘high speed’ HDMI cable is more requirable by most people. It offers users the surety that a cable has the ability to transmit all current audio formats and transmit data up to 4K resolutions. There is also an available Ultra-High-Speed HDMI cable that can run the highest rates at 8K.

Different types of HDMI Cables

The two types of HDMI cable are as follows:

Standard cables

For supporting bandwidth of about 2.23 Gbps, these cables perform at pixel speeds of 75 Mhz, also known as Category 1 HDMI cables. This is appropriate to carry an uncompressed 1080i signal.

High-Speed cables

For supporting bandwidth of about 10.2 Gbps, these cables perform at pixel speeds of 340 MHz, also known as Category 2 HDMI cables. These cables have the capability of handling the newer WQXGA and 1440p resolutions.

Advantages of HDMI

There are various advantages of using HDMI cable, which are as follows:

Higher Quality: HDMI offers better quality video at low brightness scenes with the best resolutions and enables lossless transmission. Thus, as compared to their analog counterparts, they provide much better video quality because there is conversion involved. Also, they have the ability to display sharper to high contrast details like text, etc.

Authentication and Encryption: HDMI standard ensures that the devices are authorized as it supports an authentication mechanism, which helps the HDMI-enabled sources to send the content insecure manner. They also offer surety by enabling authentication; the data, which is sent through the people, cannot be taped into the cables by people to copy or pirate that data.

Deep Colors: HDMI can render over one billion colors in good detail that supports 10-bit, 12 bit and 16-bit (RGB or YCbCr) color depths.

Single Cable: Unlike other analog cables, HDMI is able to carry audio, video, and control information through a single cable. Therefore, it makes it easy to implement an audio-video control system.

Compatibility with DVI: DVI has the capability to send HD content to display devices as HDMI is backward compatible with the DVI interface.

CEC: CEC enables devices connected via HDMI to communicate with each other as it is a communication link, which stands for Consumer Electronics Control. For instance, a single manufacturer provides multiple DVD players that can talk with each other.

Disadvantages of HDMI

An HDMI also contains numerous disadvantages some are discussed below:

Distance Limitations: HDMI Cat1 cables have the maximum distance of up to 35 meters for full capacity, and HDMI Cat2 cables are up to 10 meters. They need extenders if you cross the defined limit. There are some extenders available for HDMI, such as Coaxial extenders, UTP cable extenders, Fiber extenders, HDMI cable extenders, etc. Also, audio/video processors, Switches, Distribution amplifiers function as repeaters. But the way of extending HDMI cables may increase limitations.

Multiple locations: The HDMI cables have limitations in terms of running in multiple applications. They are complex in order to run in many different locations. As compared to the distance limitations of HDMI, there are more difficulties in such situations.

EDID: EDID also has a complexity that is used in the automatic identification of audio formats and resolutions and stands for Extended Display Identification Data. In multiple location deployment scenarios, EDID and HDMI specifications provide limited guidance.

Multi-Channel Audio: HDMI sources are not able to transmit two-channel stereo and multi-channel signals in one go, while they can transmit multi-channel audio sources. There are several devices that support different audio formats, which leads to becomes a problem with multi-room installations with HDMI.

Switching Delays: Due to authentication delays, sometimes, blank screens can be caused. Also, the screen flashing errors can be there.

Field Termination: It also includes disadvantages in terms of field terminations of HDMI cables. In the field, like their analog counterparts, they are not able to easily terminate.

Costly: As compared to analog counterparts, HDMI cables are more costly.

DVI Compatibility: Although HDMI devices are capable of supporting DVI interfaces, due to carries only video signals by DVI, HDMI devices need a separate audio cable. In such types of conditions, it also requires an HDMI-DVI connector.

Where are the HDMI ports on the back of the computer?

On the back of the computer, the HDMI ports are located on the motherboard or the video card. But there is a need to remember that HDMI connectors are not included on all types of computers. They may have DVI, VGA technology, or Display Port.

What is HDMI


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