High-Definition Multimedia Interface (HDMI) is a

proprietary {{Short pages monitor Gbit/s as well. These changes increase the aggregate bandwidth from (3 × ) to (4 × ), a 2.66× improvement in bandwidth. In addition, the data is transmitted more efficiently by using a 16b/18b encoding scheme, which uses a larger percentage of the bandwidth for data rather than DC balancing compared to the TMDS scheme used by previous versions (88.% compared to 80%). This, in combination with the 2.66× bandwidth, raises the maximum data rate of HDMI 2.1 from to 42.Gbit/s. Subtracting overhead for FEC, the usable data rate is approximately , around 2.92× the data rate of HDMI 2.0. The bandwidth provided by HDMI 2.1 is enough for 8K resolution at approximately 50Hz, with 8bpc RGB or 4:4:4 color. To achieve even higher formats, HDMI 2.1 can use

Display Stream Compression Display Stream Compression (DSC) is a VESA-developed video compression algorithm designed to enable increased display resolutions and frame rates over existing physical interfaces, and make devices smaller and lighter, with longer battery life. ...

(DSC) with a compression ratio of up to . Using DSC, formats up to 8K () 120Hz or 10K () 100Hz at 8bpc RGB/4:4:4 are possible. Using with 4:2:2 or 4:2:0 chroma subsampling in combination with DSC can allow for even higher formats. HDMI 2.1a was released on February 15, 2022, and added support for Source-Based Tone Mapping (SBTM). HDMI 2.1b was released on August 10, 2023.

Version 2.2

HDMI 2.2 was announced on January 6, 2025. It will be released in the first half of 2025. The maximum allowed bit rate is increased to and support to Latency Indication Protocol (LIP) for improving audio and video synchronization.

Version comparison

Main specifications

Refresh frequency limits for common resolutions

The maximum limits for TMDS transmission are calculated using standard data rate calculations. For FRL transmission, the limits are calculated using the capacity computation algorithm provided by the HDMI Specification. All calculations assume uncompressed RGB video with CVT-RB v2 timing. Maximum limits may differ if compression (i.e. DSC) or 4:2:0 chroma subsampling are used. Display manufacturers may also use non-standard blanking intervals (a Vendor-Specific Timing Format as defined in the HDMI Specification) rather than CVT-RB v2 to achieve even higher frequencies when bandwidth is a constraint. The refresh frequencies in the below table do not represent the absolute maximum limit of each interface, but rather an estimate based on a modern standardized timing formula. The minimum blanking intervals (and therefore the exact maximum frequency that can be achieved) will depend on the display and how many secondary data packets it requires, and therefore will differ from model to model.

Refresh frequency limits for standard video

HDMI 1.0 and 1.1 are restricted to transmitting only certain video formats, defined in EIA/CEA-861-B and in the HDMI Specification itself. HDMI 1.2 and all later versions allow any arbitrary resolution and frame rate (within the bandwidth limit). Formats that are not supported by the HDMI Specification (i.e., no standardized timings defined) may be implemented as a vendor-specific format. Successive versions of the HDMI Specification continue to add support for additional formats (such as 4K resolutions), but the added support is to establish standardized timings to ensure interoperability between products, not to establish which formats are or are not permitted. Video formats do not require explicit support from the HDMI Specification in order to be transmitted and displayed. Individual products may have heavier limitations than those listed below, since HDMI devices are not required to support the maximum bandwidth of the HDMI version that they implement. Therefore, it is not guaranteed that a display will support the refresh rates listed in this table, even if the display has the required HDMI version. Uncompressed 8bpc (24bit/px) color depth and RGB or 4:4:4 color format are assumed on this table except where noted.

Refresh frequency limits for HDR10 video

HDR10 requires 10bpc (30bit/px) color depth, which uses 25% more bandwidth than standard 8bpc video. Uncompressed 10bpc color depth and RGB or 4:4:4 color format are assumed on this table except where noted.

Feature support

The features defined in the HDMI Specification that an HDMI device may implement are listed below. For historical interest, the version of the HDMI Specification in which the feature was first added is also listed. All features of the HDMI Specification are optional; HDMI devices may implement any combination of these features. Although the "HDMI version numbers" are commonly misused as a way of indicating that a device supports certain features, this notation has no official meaning and is considered improper by HDMI Licensing. There is no officially-defined correlation between features supported by a device and any claimed "version numbers", as version numbers refer to historical editions of the HDMI Specification document, not to particular classes of HDMI devices. Manufacturers are forbidden from describing their devices using HDMI version numbers, and are required to identify support for features by listing explicit support for them, but the HDMI forum has received criticism for lack of enforcement of these policies. * Full HD

Blu-ray Disc Blu-ray (Blu-ray Disc or BD) is a Digital media, digital optical disc data storage format designed to supersede the DVD format. It was invented and developed in 2005 and released worldwide on June 20, 2006, capable of storing several hours of ...

and

HD DVD HD DVD (short for High Density Digital Versatile Disc) is an obsolete high-density optical disc format for storing data and playback of high-definition video.

video (version 1.0) * Consumer Electronic Control (CEC) (version 1.0) *

DVD-Audio DVD-Audio (commonly abbreviated as DVD-A) is a digital format for delivering high-fidelity audio content on a DVD. DVD-Audio uses most of the storage on the disc for high-quality audio and is not intended to be a video delivery format. The ...

(version 1.1) *

Super Audio CD Super Audio CD (SACD) is an optical disc format for audio storage introduced in 1999. It was developed jointly by Sony and Philips Electronics and intended to be the successor to the compact disc (CD) format. The SACD format allows multiple a ...

( DSD) (version 1.2) * Auto

Lip-Sync Lip sync or lip synch (pronounced , like the word ''sink'', despite the spelling of the participial forms ''synced'' and ''syncing''), short for lip synchronization, is a technical term for matching a speaking or singing person's lip movements ...

Correction (version 1.3) *

Dolby TrueHD Dolby TrueHD is a lossless, multi-channel audio codec developed by Dolby Laboratories for home video, used principally in Blu-ray Disc and compatible hardware. Dolby TrueHD, along with Dolby Digital Plus (E-AC-3) and Dolby AC-4, is one of th ...

DTS-HD Master Audio DTS-HD Master Audio (DTS-HD MA; known as DTS++ before 2004) is a multi-channel, lossless audio codec developed by DTS as an extension of the lossy DTS Coherent Acoustics codec (DTS CA; usually itself referred to as just DTS). Rather than be ...

bitstream capable (version 1.3) * Updated list of CEC commands (version 1.3a) * 3D video (version 1.4) * Ethernet channel (100Mbit/s) (version 1.4) * Audio return channel (ARC) (version 1.4) * 4 audio streams (version 2.0) * Dual View (version 2.0) * Perceptual quantizer HDR EOTF (SMPTE ST 2084) (version 2.0a) *

Hybrid log–gamma The hybrid log–gamma (HLG) transfer function is a transfer function jointly developed by the BBC and NHK for high dynamic range (HDR) display. It is backward compatible with the transfer function of SDR (the gamma curve). It was approved as ARIB ...

(HLG) HDR EOTF (version 2.0a) * Static HDR metadata ( SMPTE ST 2086) (version 2.0a) * Dynamic HDR metadata ( SMPTE ST 2094) (version 2.0b) * Enhanced audio return channel (eARC) (version 2.1) * Variable Refresh Rate (VRR) (version 2.1) * Quick Media Switching (QMS) (version 2.1) * Quick Frame Transport (QFT) (version 2.1) * Auto Low Latency Mode (ALLM) (version 2.1) * Display Stream Compression (DSC) (version 2.1) * Source-Based Tone Mapping (SBTM) (version 2.1a)

Display Stream Compression

'' (DSC) is a

VESA VESA (), formally known as Video Electronics Standards Association, is an American standards organization, technical standards organization for computer display standards. The organization was incorporated in California in July 1989To retrieve ...

-developed video compression algorithm designed to enable increased display resolutions and frame rates over existing physical interfaces, and make devices smaller and lighter, with longer battery life.

Applications

Blu-ray Disc and HD DVD players

and

HD DVD HD DVD (short for High Density Digital Versatile Disc) is an obsolete high-density optical disc format for storing data and playback of high-definition video.

, introduced in 2006, offer high-fidelity audio features that require HDMI for best results. HDMI 1.3 can transport

Dolby Digital Plus Dolby Digital Plus, also known as Enhanced AC-3 (and commonly abbreviated as DDP, DD+, E-AC-3 or EC-3), is a digital audio compression scheme developed by Dolby Labs for the transport and storage of multi-channel digital audio. It is a successo ...

, and

bitstreams in compressed form. This capability allows for an

AV receiver An audio/video receiver (AVR) or a stereo receiver is a consumer electronics component used in a home theater, home audio, or hi-fi system. Its purpose is to receive audio and video signals from a number of sources, and to process them and prov ...

with the necessary decoder to decode the compressed audio stream. The Blu-ray specification does not include video encoded with either deep color or xvYCC; thus, HDMI 1.0 can transfer Blu-ray discs at full video quality. The HDMI 1.4 specification (released in 2009) added support for 3D video and is used by all Blu-ray 3D compatible players. The Blu-ray Disc Association (BDA) spokespersons have stated (Sept. 2014 at IFA show in Berlin, Germany) that the Blu-ray, Ultra HD players, and 4K discs are expected to be available starting in the second half to 2015. It is anticipated that such Blu-ray UHD players will be required to include a HDMI 2.0 output that supports HDCP 2.2. Blu-ray permits secondary audio decoding, whereby the disc content can tell the player to mix multiple audio sources together before final output. Some Blu-ray and HD DVD players can decode all of the audio

codec A codec is a computer hardware or software component that encodes or decodes a data stream or signal. ''Codec'' is a portmanteau of coder/decoder. In electronic communications, an endec is a device that acts as both an encoder and a decoder o ...

s internally and can output LPCM audio over HDMI. Multichannel LPCM can be transported over an HDMI connection, and as long as the

implements multichannel LPCM audio over HDMI and implements

HDCP High-bandwidth Digital Content Protection (HDCP) is a form of digital copy protection developed by Intel Corporation to prevent copying of digital audio and video content as it travels across connections. Types of connections include DisplayPort ...

, the audio reproduction is equal in resolution to HDMI 1.3 bitstream output. Some low-cost AV receivers, such as the Onkyo TX-SR506, do not allow audio processing over HDMI and are labelled as "HDMI pass through" devices. Virtually all modern AV Receivers now offer HDMI 1.4 inputs and outputs with processing for all of the audio formats offered by Blu-ray Discs and other HD video sources. During 2014 several manufacturers introduced premium AV Receivers that include one, or multiple, HDMI 2.0 inputs along with a HDMI 2.0 output(s). However, not until 2015 did most major manufacturers of AV receivers also support HDCP 2.2 as needed to support certain high quality UHD video sources, such as Blu-ray UHD players.

Digital cameras and camcorders

Most consumer camcorders, as well as many digital cameras, are equipped with a mini-HDMI connector (type C connector). Some cameras also have 4K capability, although cameras capable of

HD video High-definition video (HD video) is video of higher resolution and quality than standard-definition. While there is no standardized meaning for ''high-definition'', generally any video image with considerably more than 480 vertical scan lines (N ...

often include an HDMI interface for playback or even

live preview Live preview is a feature that allows a digital camera's display screen to be used as a viewfinder. This provides a means of previewing framing and other exposure before taking the photograph. In most such cameras, the preview is generated by ...

, the

image processor An image processor, also known as an image processing engine, image processing unit (IPU), or image signal processor (ISP), is a type of media processor or specialized digital signal processor (DSP) used for image processing, in digital cameras o ...

and the video processor of cameras usable for uncompressed video must be able to deliver the full

image resolution Image resolution is the level of detail of an image. The term applies to digital images, film images, and other types of images. "Higher resolution" means more image detail. Image resolution can be measured in various ways. Resolution quantifies ...

at the specified

frame rate Frame rate, most commonly expressed in frame/s, or FPS, is typically the frequency (rate) at which consecutive images (Film frame, frames) are captured or displayed. This definition applies to film and video cameras, computer animation, and moti ...

in real time without any missing frames causing jitter. Therefore, usable uncompressed video out of HDMI is often called "clean HDMI".

Personal computers

Personal computer A personal computer, commonly referred to as PC or computer, is a computer designed for individual use. It is typically used for tasks such as Word processor, word processing, web browser, internet browsing, email, multimedia playback, and PC ...

(PCs) with a DVI interface are capable of video output to an HDMI-enabled monitor. Some PCs include an HDMI interface and may also be capable of HDMI audio output, depending on specific hardware. For example, Intel's motherboard chipsets since the 945G and NVIDIA's

GeForce GeForce is a brand of graphics processing units (GPUs) designed by Nvidia and marketed for the performance market. As of the GeForce 50 series, there have been nineteen iterations of the design. In August 2017, Nvidia stated that "there are o ...

8200/8300 motherboard chipsets are capable of 8-channel LPCM output over HDMI. Eight-channel LPCM audio output over HDMI with a video card was first seen with the ATI Radeon HD 4850, which was released in June 2008 and is implemented by other video cards in the ATI Radeon HD 4000 series.

Linux Linux ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, pac ...

can drive 8-channel LPCM audio over HDMI if the video card has the necessary hardware and implements the

Advanced Linux Sound Architecture Advanced Linux Sound Architecture (ALSA) is a software framework and part of the Linux kernel that provides an application programming interface (API) for sound card device drivers. Some of the goals of the ALSA project at its inception were ...

(ALSA). The ATI Radeon HD 4000 series implements ALSA. Cyberlink announced in June 2008 that they would update their PowerDVD playback software to allow 192 kHz/24-bit Blu-ray Disc audio decoding in Q3-Q4 of 2008. Corel's WinDVD 9 Plus currently has 96 kHz/24-bit Blu-ray Disc audio decoding. Even with an HDMI output, a computer may not be able to produce signals that implement

, Microsoft's Protected Video Path, or Microsoft's Protected Audio Path. Several early graphic cards were labelled as "HDCP-enabled" but did not have the hardware needed for HDCP; this included some graphic cards based on the ATI X1600 chipset and certain models of the NVIDIA Geforce 7900 series. The first computer monitors that could process HDCP were released in 2005; by February 2006 a dozen different models had been released. The Protected Video Path was enabled in graphic cards that had HDCP capability, since it was required for output of Blu-ray Disc and HD DVD video. In comparison, the Protected Audio Path was required only if a lossless audio bitstream (such as Dolby TrueHD or DTS-HD MA) was output. Uncompressed LPCM audio, however, does not require a Protected Audio Path, and software programs such as PowerDVD and WinDVD can decode Dolby TrueHD and DTS-HD MA and output it as LPCM. A limitation is that if the computer does not implement a Protected Audio Path, the audio must be downsampled to 16-bit 48 kHz but can still output at up to 8 channels. No graphic cards were released in 2008 that implemented the Protected Audio Path. The

Asus ASUSTeK Computer Inc. (, , , ; stylized as ASUSTeK or ASUS) is a Taiwanese Multinational corporation, multinational computer, phone hardware and electronics manufacturer headquartered in Beitou District, Taipei, Taiwan. Its products include deskto ...

Xonar HDAV1.3 became the first HDMI sound card that implemented the Protected Audio Path and could both bitstream and decode lossless audio (Dolby TrueHD and DTS-HD MA), although bitstreaming is only available if using the ArcSoft TotalMedia Theatre software. It has an HDMI 1.3 input/output, and Asus says that it can work with most video cards on the market. In September 2009,

AMD Advanced Micro Devices, Inc. (AMD) is an American multinational corporation and technology company headquartered in Santa Clara, California and maintains significant operations in Austin, Texas. AMD is a hardware and fabless company that de ...

announced the ATI

Radeon HD 5000 series The Evergreen series is a family of graphics processing unit, GPUs developed by Advanced Micro Devices for its Radeon line under the ATI Technologies, ATI brand name. It was employed in Radeon HD 5000 graphics card series and competed directly w ...

video cards, which have HDMI 1.3 output (deep color, xvYCC wide gamut capability and high bit rate audio), 8-channel LPCM over HDMI, and an integrated HD audio controller with a Protected Audio Path that allows bitstream output over HDMI for AAC, Dolby AC-3, Dolby TrueHD and DTS-HD Master Audio formats. The ATI Radeon HD 5870 released in September 2009 is the first video card that allows bitstream output over HDMI for Dolby TrueHD and DTS-HD Master Audio. The AMD

Radeon HD 6000 series The Northern Islands series is a family of GPUs developed by Advanced Micro Devices (AMD) forming part of its Radeon-brand, based on the 40 nm process. Some models are based on TeraScale 2 (VLIW5), some on the new TeraScale 3 (VLIW4) intr ...

implements HDMI 1.4a. The AMD

Radeon HD 7000 series The Radeon HD 7000 series, codenamed "Southern Islands", is a family of GPUs developed by AMD, and manufactured on TSMC's 28 nm process. The primary competitor of Southern Islands was Nvidia's GeForce 600 series (also manufactured at TS ...

implements HDMI 1.4b. In December 2010, it was announced that several computer vendors and display makers including

Intel Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California, and Delaware General Corporation Law, incorporated in Delaware. Intel designs, manufactures, and sells computer compo ...

, AMD,

Dell Dell Inc. is an American technology company that develops, sells, repairs, and supports personal computers (PCs), Server (computing), servers, data storage devices, network switches, software, computer peripherals including printers and webcam ...

Lenovo Lenovo Group Limited, trading as Lenovo ( , zh, c=联想, p=Liánxiǎng), is a Chinese multinational technology company specializing in designing, manufacturing, and marketing consumer electronics, personal computers, software, servers, conv ...

Samsung Samsung Group (; stylised as SΛMSUNG) is a South Korean Multinational corporation, multinational manufacturing Conglomerate (company), conglomerate headquartered in the Samsung Town office complex in Seoul. The group consists of numerous a ...

, and LG would stop using

LVDS Low-voltage differential signaling (LVDS), also known as TIA/EIA-644, is a technical standard that specifies electrical characteristics of a differential, serial signaling standard. LVDS operates at low power and can run at very high speeds u ...

(actually,

FPD-Link Flat Panel Display Link, more commonly referred to as FPD-Link, is the original high-speed digital video interface created in 1996 by National Semiconductor (now within Texas Instruments). It is a free and open standard for connecting the outp ...

) from 2013 and legacy DVI and

VGA Video Graphics Array (VGA) is a video display controller and accompanying de facto graphics standard, first introduced with the IBM PS/2 line of computers in 1987, which became ubiquitous in the IBM PC compatible industry within three years. T ...

connectors from 2015, replacing them with

DisplayPort DisplayPort (DP) is a digital interface used to connect a video source, such as a Personal computer, computer, to a display device like a Computer monitor, monitor. Developed by the Video Electronics Standards Association (VESA), it can also car ...

and HDMI. On August 27, 2012, Asus announced a new monitor that produces its native resolution of 2560×1440 via HDMI 1.4. On September 18, 2014, Nvidia launched GeForce GTX 980 and GTX 970 (with GM204 chip) with HDMI 2.0 support. On January 22, 2015, GeForce GTX 960 (with GM206 chip) launched with HDMI 2.0 support. On March 17, 2015, GeForce GTX TITAN X (GM200) launched with HDMI 2.0 support. On June 1, 2015, GeForce GTX 980 Ti (with GM200 chip) launched with HDMI 2.0 support. On August 20, 2015, GeForce GTX 950 (with GM206 chip) launched with HDMI 2.0 support. On May 6, 2016, Nvidia launched the GeForce GTX 1080 (GP104 GPU) with HDMI 2.0b support. On September 1, 2020, Nvidia launched the GeForce RTX 30 series, the world's first discrete graphics cards with support for the full bandwidth with Display Stream Compression 1.2 of HDMI 2.1.

Gaming consoles

Beginning with the

seventh generation of video game consoles The seventh generation of home video game consoles began on November 22, 2005, with the release of Microsoft's Xbox 360 home console. This was followed by the release of Sony's PlayStation 3 on November 17, 2006, and Nintendo's Wii on November ...

, most consoles support HDMI. Video game consoles that support HDMI include the

Xbox 360 The Xbox 360 is a home video game console developed by Microsoft. As the successor to the Xbox (console), original Xbox, it is the second console in the Xbox#Consoles, Xbox series. It was officially unveiled on MTV on May 12, 2005, with detail ...

(except most pre-2007 models) (1.2a),

Xbox One The Xbox One is a home video game console developed by Microsoft. Announced in May 2013, it is the successor to Xbox 360 and the third console in the Xbox#Consoles, Xbox series. It was first released in North America, parts of Europe, Austra ...

(1.4b), Xbox One S (2.0a),

Xbox One X The Xbox One is a home video game console developed by Microsoft. Announced in May 2013, it is the successor to Xbox 360 and the third console in the Xbox series. It was first released in North America, parts of Europe, Australia, and South ...

(2.0b),

PlayStation 3 The PlayStation 3 (PS3) is a home video game console developed and marketed by Sony Computer Entertainment (SCE). It is the successor to the PlayStation 2, and both are part of the PlayStation brand of consoles. The PS3 was first released on ...

(1.3a),

PlayStation 4 The PlayStation 4 (PS4) is a home video game console developed by Sony Interactive Entertainment. Announced as the successor to the PlayStation 3 in February 2013, it was launched on November 15, 2013, in North America, November 29, 2013, in ...

(1.4b), PlayStation 4 Pro (2.0a),

Wii U The Wii U ( ) is a home video game console developed by Nintendo as the successor to the Wii. Released in late 2012, it is the first eighth-generation video game console and competed with Microsoft's Xbox One and Sony's PlayStation 4. The W ...

(1.4a),

Nintendo Switch The is a video game console developed by Nintendo and released worldwide in most regions on March 3, 2017. Released in the middle of the Eighth generation of video game consoles, eighth generation of home consoles, the Switch succeeded the ...

(1.4b), Nintendo Switch (OLED model) (2.0a),

Xbox Series X and Series S The Xbox Series X and Xbox Series S are the fourth generation of consoles in the Xbox series, succeeding the previous generation's Xbox One. Released on November 10, 2020, the higher-end Xbox Series X and lower-end Xbox Series S are part o ...

(2.1),

PlayStation 5 The PlayStation 5 (PS5) is a home video game console developed by Sony Interactive Entertainment. It was announced as the successor to the PlayStation 4 in April 2019, was launched on November 12, 2020, in Australia, Japan, New Zealand, North ...

(2.1), And

Nintendo Switch 2 The is a hybrid video game console developed by Nintendo, released in most regions on June5, 2025. Like the original Nintendo Switch, Switch, it can be used as a Handheld game console, handheld, as a Tablet computer, tablet, or connected via ...

Tablet computers

Some

tablet computer A tablet computer, commonly shortened to tablet, is a mobile device, typically with a mobile operating system and touchscreen display processing circuitry, and a rechargeable battery in a single, thin and flat package. Tablets, being computers ...

s implement HDMI using Micro-HDMI (type D) port, while others like the Eee Pad Transformer implement the standard using mini-HDMI (type C) ports. All

iPad The iPad is a brand of tablet computers developed and marketed by Apple Inc., Apple that run the company's mobile operating systems iOS and later iPadOS. The IPad (1st generation), first-generation iPad was introduced on January 27, 2010. ...

models have a special A/V adapter that converts Apple's

Lightning connector Lightning is a proprietary computer bus and power connector, created and designed by Apple Inc. It was introduced on September 12, 2012, in conjunction with the iPhone 5, to replace its predecessor, the 30-pin dock connector. The Lightning c ...

to a standard HDMI (type A) port. Samsung has a similar proprietary thirty-pin port for their Galaxy Tab 10.1 that could adapt to HDMI as well as USB drives. The Dell Streak 5 smartphone/tablet hybrid is capable of outputting over HDMI. While the Streak uses a PDMI port, a separate cradle adds HDMI compatibility. Some tablets running

Android OS Android is an operating system based on a modified version of the Linux kernel and other open-source software, designed primarily for touchscreen-based mobile devices such as smartphones and tablets. Android has historically been developed b ...

provide HDMI output using a mini-HDMI (type C) port. Most new laptops and desktops now have built in HDMI as well.

Mobile phones

Many mobile phones can produce an output of HDMI video via a micro-HDMI connector, SlimPort, MHL or other adapter.

Legacy compatibility

HDMI can only be used with older analog-only devices (using connections such as

SCART SCART (also known as or , especially in France, 21-pin EuroSCART in marketing by Sharp Corporation, Sharp in Asia, Euroconector in Spain, EuroAV or EXT, or EIA Multiport in the United States, as an EIA interface) is a French-originated standard ...

, RCA, etc.) by means of a

digital-to-analog converter In electronics, a digital-to-analog converter (DAC, D/A, D2A, or D-to-A) is a system that converts a digital signal into an analog signal. An analog-to-digital converter (ADC) performs the reverse function. DACs are commonly used in musi ...

, as the interface does not carry any analog signals (unlike DVI, where devices with DVI-I ports accept or provide either digital or analog signals). Cables are available that contain the necessary electronics, but it is important to distinguish these ''active'' converter cables from ''passive'' HDMI to VGA cables (which are typically cheaper as they don't include any electronics). The passive cables are ''only'' useful if a user has a device that is generating or expecting HDMI signals on a VGA connector, or VGA signals on an HDMI connector; this is a non-standard feature, not implemented by most devices.

HDMI Alternate Mode for USB Type-C

The HDMI Alternate Mode for

USB-C USB-C, or USB Type-C, is a 24-pin reversible Electrical connector, connector (not a Communication protocol, protocol) that supersedes previous USB hardware#Connectors, USB connectors (also supersedes Mini DisplayPort and Lightning (connector) ...

allows HDMI-enabled sources with a USB-C connector to directly connect to standard HDMI display devices, without requiring an adapter. The standard was released in September 2016, and supports all HDMI 1.4b features such as video resolutions up to

Ultra HD Ultra-high-definition television (also known as Ultra HD television, Ultra HD, UHDTV, UHD and Super Hi-Vision) today includes 4K resolution#Resolutions, 4K UHD and 8K resolution#Resolutions, 8K UHD, which are two digital video formats with an ...

30 Hz and CEC. Previously, the similar

Alternate Mode could be used to connect to HDMI displays from USB Type-C sources, but where in that case active adapters were required to convert from DisplayPort to HDMI, HDMI Alternate Mode connects to the display natively. The Alternate Mode reconfigures the four SuperSpeed differential pairs present in USB-C to carry the three HDMI TMDS channels and the clock signal. The two Sideband Use pins (SBU1 and SBU2) are used to carry the HDMI Ethernet and Audio Return Channel and the Hot Plug Detect functionality (HEAC+/Utility pin and HEAC−/HPD pin). As there are not enough reconfigurable pins remaining in USB-C to accommodate the DDC clock (SCL), DDC data (SDA), and CECthese three signals are bridged between the HDMI source and sink via the USB Power Delivery 2.0 (USB-PD) protocol, and are carried over the USB-C Configuration Channel (CC) wire. This is possible because the cable is electronically marked (i.e., it contains a USB-PD node) that serves to tunnel the DDC and CEC from the source over the Configuration Channel to the node in the cable, these USB-PD messages are received and relayed to the HDMI sink as regenerated DDC (SCL and SDA signals), or CEC signals. As stated at CES in January 2023, HDMI Alternate Mode for USB Type-C is no longer being updated as there are no known products using this protocol, reducing its relevance in the current market. This will reduce consumer confusion as

Alternate Mode is the primary video protocol of choice over USB-C. HDMI Alt Mode - USB Type-C pin mapping

Relationship with DisplayPort

The

audio/video interface was introduced in May 2006 by the

Video Electronics Standards Association VESA (), formally known as Video Electronics Standards Association, is an American technical standards organization for computer display standards. The organization was incorporated in California in July 1989To retrieve the information, sear ...

(VESA). Historically, HDMI Licensing LLC was publicly dismissive of DisplayPort's position in the industry, with its president stating in a 2009 interview that "there are certainly some PCs that have DisplayPort connectors on them, but these are niche applications that have not taken hold in the market." In recent years, DisplayPort connectors have become a common feature of premium products—displays, desktop computers, and video cards; most of the companies producing DisplayPort equipment are in the computer sector. The DisplayPort website states that DisplayPort is expected to complement HDMI, but 100% of HD and UHD TVs had HDMI connectivity. DisplayPort supported some advanced features which are useful for multimedia content creators and gamers (e.g., 5K, Adaptive-Sync), which was the reason most GPUs have DisplayPort. These features were added to the official HDMI specification slightly later, but with the introduction of HDMI 2.1, these gaps are already leveled off (e.g., VRR /

Variable Refresh Rate Variable refresh rate (VRR) refers to a dynamic display that can continuously and seamlessly change its refresh rate without user input. A display supporting a variable refresh rate usually supports a specific range of refresh rates (e.g. 30 Hertz ...

). DisplayPort uses a self-clocking, micro-packet-based protocol that allows for a variable number of differential pair lanes as well as flexible allocation of bandwidth between audio and video, and allows encapsulating multi-channel compressed audio formats in the audio stream. DisplayPort 1.2 supports multiple audio/video streams, variable refresh rate (

FreeSync FreeSync is an adaptive synchronization technology that allows LCD and OLED displays to support a variable refresh rate aimed at avoiding tearing and reducing stuttering caused by misalignment between the screen's refresh rate and the content's ...

), and Dual-mode transmitters compatible with HDMI 1.2 or 1.4. Revision 1.3 increases overall transmission bandwidth to with the new HBR3 mode featuring per lane; it requires Dual-mode with mandatory HDMI 2.0 compatibility and

2.2. Revision 1.4 added Display Stream Compression (DSC), support for the BT.2020 color space, and

HDR10 HDR10 Media Profile, more commonly known as 'HDR10'', is an open high-dynamic-range video (HDR) standard announced on 27 August 2015, by the Consumer Electronics Association. It is the most widespread HDR format. HDR10 is not Backward compatibil ...

extensions from CTA-861.3, including static and dynamic metadata. Revision 1.4a was published in April 2018, updating DisplayPort's DSC implementation from 1.2 to 1.2a. Revision 2.0 increased overall bandwidth from 25.92 to , enabling increased resolutions and refresh rates, increasing the resolutions and refresh rates with HDR support, and other related improvements. Revision 2.1 was published in October 2022, incorporating the new DP40 and DP80 cable certifications, which require proper operation at the UHBR10 (40Gbit/s) and UHBR20 (80Gbit/s) speeds introduced in version 2.0, and a bandwidth management feature to enable DisplayPort tunnelling to coexist with other I/O data traffic more efficiently over a USB4/USB Type-C connection. The DisplayPort features an adapter detection mechanism enabling dual-mode operation and the transmission of TMDS signals allowing the conversion to DVI and HDMI 1.2/1.4/2.0 signals using a passive adapter. The same external connector is used for both protocolswhen a DVI/HDMI passive adapter is attached, the transmitter circuit switches to TMDS mode. DisplayPort Dual-mode ports and cables/adapters are typically marked with the DisplayPort++ logo.

Thunderbolt A thunderbolt or lightning bolt is a symbolic representation of lightning when accompanied by a loud thunderclap. In Indo-European mythology, the thunderbolt was identified with the 'Sky Father'; this association is also found in later Hel ...

ports with mDP connector also supports Dual-mode passive HDMI adapters/cables. Conversion to dual-link DVI and

component video Component video is an analog video signal that has been split into two or more component channels. In popular use, it refers to a type of component analog video (CAV) information that is transmitted or stored as three separate signals. Compo ...

(VGA/YPbPr) requires active powered adapters. The USB 3.1 type-C connector is increasingly the standard video connector, replacing legacy video connectors such as mDP, Thunderbolt, HDMI, and VGA in mobile devices. USB-C connectors can transmit DisplayPort video to docks and displays using standard USB type-C cables or type-C to DisplayPort cables and adapters; USB-C also supports HDMI adapters that actively convert from DisplayPort to HDMI 1.4 or 2.0. DisplayPort Alternate Mode for USB type-C specification was published in 2015. USB type-C chipsets are not required to include Dual-mode, so passive DP-HDMI adapters do not work with type-C sources. A specification for "HDMI Alternate Mode for USB type-C" was released in 2016, but was discontinued in 2023, with HDMI Licensing Administration stating they knew of no adapter having ever been produced. DisplayPort is royalty-free, though

patent pool In patent law, a patent pool is a consortium of two or more companies agreeing to cross-license patents relating to a particular technology. The creation of a patent pool can save patentees and licensees time and money, and, in case of blocking pa ...

administrator Via LA attempts to collect a $0.20 per-device charge for a bulk license to patents it regards as essential to the DisplayPort specification, while HDMI has an annual fee of US$10,000 and a per unit royalty rate of between $0.04 and $0.15. HDMI has had a few advantages over DisplayPort, such as ability to carry Consumer Electronics Control (CEC) signals since its first generation (DisplayPort 1.3, introduced in 2014, is the earliest DisplayPort generation which can carry CEC signals).

Relationship with MHL

Mobile High-Definition Link (MHL) is an adaptation of HDMI intended to connect mobile devices such as smartphones and tablets to high-definition televisions (HDTVs) and displays. Unlike DVI, which is compatible with HDMI using only passive cables and adapters, MHL requires that the HDMI socket be MHL-enabled, otherwise an active adapter (or

dongle A dongle is a small piece of computer hardware that connects to a port on another device to provide it with additional functionality, or enable a pass-through to such a device that adds functionality. In computing, the term was initially synony ...

) is required to convert the signal to HDMI. MHL is developed by a

consortium A consortium () is an association of two or more individuals, companies, organizations, or governments (or any combination of these entities) with the objective of participating in a common activity or pooling their resources for achieving a ...

of five consumer electronics manufacturers, several of which are also behind HDMI. MHL pares down the three TMDS channels in a standard HDMI connection to a single one running over any connector that provides at least five pins. This lets existing connectors in mobile devicessuch as

micro-USB The initial versions of the USB standard specified connectors that were easy to use and that would have high life spans; revisions of the standard added smaller connectors useful for compact portable devices. Higher-speed development of the USB ...

be used, avoiding the need for additional dedicated video output sockets. The USB port switches to MHL mode when it detects a compatible device is connected. In addition to the features in common with HDMI (such as

encrypted

uncompressed In information theory, data compression, source coding, or bit-rate reduction is the process of encoding information using fewer bits than the original representation. Any particular compression is either lossy or lossless. Lossless compression ...

high-definition video High-definition video (HD video) is video of higher resolution and quality than standard-definition. While there is no standardized meaning for ''high-definition'', generally any video image with considerably more than 480 vertical scan lines ( ...

and eight-channel

surround sound Surround sound is a technique for enriching the fidelity and depth of sound reproduction by using multiple audio channels from speakers that surround the listener ( surround channels). Its first application was in movie theaters. Prior to ...

), MHL also adds the provision of power charging for the mobile device while in use, and also enables the TV remote to control it. Although support for these additional features requires connection to an MHL-enabled HDMI port, power charging can also be provided when using active MHL to HDMI adapters (connected to standard HDMI ports), provided there is a separate power connection to the adapter. Like HDMI, MHL defines a

Alternate Mode to support the MHL standard over USB-C connections. Version 1.0 supported 720p/1080i 60 Hz (RGB/4:4:4 pixel encoding) with a bandwidth of . Versions 1.3 and 2.0 added support for

1080p 1080p (1920 × 1080 progressively displayed pixels; also known as Full HD or FHD, and BT.709) is a set of HDTV high-definition video modes characterized by 1,920 pixels displayed across the screen horizontally and 1,080 pixels down the sc ...

60 Hz ( 4:2:2) with a bandwidth of in PackedPixel mode. Version 3.0 increased the bandwidth to to support

(3840 × 2160) 30 Hz video, and also changed from being frame-based, like HDMI, to packet-based. The fourth version, superMHL, increased bandwidth by operating over multiple TMDS differential pairs (up to a total of six) allowing a maximum of . The six lanes are supported over a reversible 32-pin superMHL connector, while four lanes are supported over USB-C Alternate Mode (only a single lane is supported over micro-USB/HDMI).

(DSC) is used to allow up to 8K Ultra HD (7680 × 4320) 120 Hz HDR video, and to support Ultra HD 60 Hz video over a single lane.

Footnotes

References

External links

HDMI Licensing, LLC.

Dolby Podcast Episode 60 – March 26, 2009
art one of a two-part discussion with Steve Venuti, President, and Jeff Park, Technology Evangelist, of HDMI Licensing.
Dolby Podcast Episode 62 – April 23, 2009
art two of a two-part discussion with Steve Venuti, President, and Jeff Park, Technology Evangelist, of HDMI Licensing. {{DEFAULTSORT:Hdmi Audiovisual connectors Audiovisual introductions in 2002 Computer connectors Computer display standards Digital display connectors High-definition television Japanese inventions Television technology Television terminology Television transmission standards Video signal Serial buses