HDMI

The HDMI founders were Hitachi, Panasonic, Sanyo (as a Panasonic affiliate), Philips, Silicon Image (now Lattice Semiconductor), Sony, Thomson (now Vantiva), and Toshiba. Intel contributed the HDCP copy protection system. The new format won the support of motion picture studios Fox, Universal, Warner Bros. and Disney, along with content distributors DirecTV, EchoStar (Dish Network) and CableLabs. At the time, DVI-HDCP (DVI with HDCP) and DVI-HDTV (DVI-HDCP using the CEA-861-B video standard) were being used on HDTVs. HDMI 1.0 was designed to improve on DVI-HDTV by using a smaller connector and adding audio capability, enhanced YCbCr| capability, and consumer electronics control functions. The first ATC in Japan was opened by Panasonic on May 1, 2004, in Osaka. The first ATC in Europe was opened by Philips on May 25, 2005, in Caen, France. The first ATC in China was opened by Silicon Image on November 21, 2005, in Shenzhen. The first ATC in India was opened by Philips on June 12, 2008, in Bangalore. The HDMI website contains a list of all the ATCs. According to In-Stat, the number of HDMI devices sold was 5 million in 2004, 17.4 million in 2005, 63 million in 2006, and 143 million in 2007. HDMI has become the de facto standard for HDTVs, and according to In-Stat, around 90% of digital televisions in 2007 included HDMI. In-Stat has estimated that 229 million HDMI devices were sold in 2008. On April 8, 2008, there were over 850 consumer electronics and PC companies that had adopted the HDMI specification (HDMI adopters). On January 7, 2009, HDMI Licensing, LLC announced that HDMI had reached an installed base of over 600 million HDMI devices. In 2008, PC Magazine awarded a Technical Excellence Award in the Home Theater category for an "innovation that has changed the world" to the CEC portion of the HDMI specification. Ten companies were given a Technology and Engineering Emmy Award for their development of HDMI by the National Academy of Television Arts and Sciences on January 7, 2009. On October 25, 2011, the HDMI Forum was established by the HDMI founders. On January 8, 2013, HDMI Licensing, LLC announced that there were over 1,300 HDMI adopters and that over 3 billion HDMI devices had shipped since the launch of the HDMI standard. The day also marked the 10th anniversary of the release of the first HDMI specification. ==Specifications==

The HDMI specification defines the protocols, signals, electrical interfaces and mechanical requirements of the standard. The maximum pixel clock rate for HDMI 1.0 is 165 MHz, which is sufficient to allow 1080p and WUXGA (1920×1200) at 60Hz. HDMI 1.3 increases that to 340 MHz, which allows for higher resolution (such as WQXGA, 2560×1600) across a single digital link. An HDMI connection can either be single-link (type A/C/D) or dual-link (type B) and can have a video pixel rate of 25 MHz to 340 MHz (for a single-link connection) or 25 MHz to 680 MHz (for a dual-link connection). Video formats with pixel rates below 25 MHz (like 480i at 13.5 MHz) are transmitted over TMDS links using a pixel-repetition scheme. On July 15, 2013, the CEA announced the publication of CEA-861-F, a standard that can be used by video interfaces such as DVI, HDMI, and LVDS. CEA-861-F adds the ability to transmit several Ultra HD video formats and additional color spaces. As such, any closed caption stream must be decoded and included as an image in the video stream(s) prior to transmission over an HDMI cable to appear on the DTV. This limits the caption style (even for digital captions) to only that decoded at the source prior to HDMI transmission. This also prevents closed captions when transmission over HDMI is required for upconversion. For example, a DVD player that sends an upscaled 720p/1080i format via HDMI to an HDTV has no way to pass Closed Captioning data so that the HDTV can decode it, as there is no line 21 VBI in that format. Communication channels HDMI has three physically separate communication channels, which are the VESA DDC, TMDS and the optional CEC. by using only one of their remote controls (for example by controlling a television set, set-top box, and DVD player using only the remote control of the TV). CEC also allows for individual CEC-enabled devices to command and control each other without user intervention. CEC wiring is mandatory, although implementation of CEC in a product is optional. HDMI Ethernet and Audio Return Channel Introduced in HDMI 1.4, HDMI Ethernet and Audio Return Channel (HEAC) adds a high-speed bidirectional data communication link (HEC) and the ability to send audio data upstream to the source device (ARC). HEAC utilizes two lines from the connector: the previously unused Reserved pin (called HEAC+) and the Hot Plug Detect pin (called HEAC−). If only ARC transmission is required, a single mode signal using the HEAC+ line can be used, otherwise, HEC is transmitted as a differential signal over the pair of lines, and ARC as a common mode component of the pair. ARC supports stereo PCM and compressed codecs Dolby Digital, Dolby Digital Plus and DTS up to 5.1 channels, with Dolby Atmos metadata in Dolby codecs. eARC (Enhanced Audio Return Channel) was introduced in 2017 with the HDMI 2.1 standard. eARC has higher bandwidth (37 Mbps) and adds support for uncompressed surround sound, Dolby TrueHD and DTS-HD Master Audio passthrough with support for up to 32 channels. eARC requires an "Ultra High Speed", "Premium High Speed with Ethernet", or "High Speed with Ethernet" HDMI cable. HDMI Ethernet Channel (HEC) HDMI Ethernet Channel technology consolidates video, audio, and data streams into a single HDMI cable, and the HEC feature enables IP-based applications over HDMI and provides a bidirectional Ethernet communication at . Compatibility with DVI HDMI is backward compatible with single-link Digital Visual Interface digital video (DVI-D or DVI-I, but not DVI-A or dual-link DVI). No signal conversion is required when an adapter or asymmetric cable is used, so there is no loss of video quality. A further complication is that there is a small amount of display equipment, such as some high-end home theater projectors, designed with HDMI inputs but not HDCP-compliant. Any DVI-to-HDMI adapter can function as an HDMI-to-DVI adapter (and vice versa). Typically, the only limitation is the gender of the adapter's connectors and the gender of the cables and sockets it is used with. Features specific to HDMI, such as remote-control and audio transport, are not available in devices that use legacy DVI-D signalling. However, many devices output HDMI over a DVI connector (e.g., ATI HD 2000-series and Nvidia GTX 200-series video cards), and some multimedia displays may accept HDMI (including audio) over a DVI input. Exact capabilities beyond basic compatibility vary. Adapters are generally bi-directional. Content protection (HDCP) High-bandwidth Digital Content Protection (HDCP) is a newer form of digital rights management (DRM). Intel created the original technology to make sure that digital content followed the guidelines set by the Digital Content Protection group. HDMI can use HDCP to encrypt the signal if required by the source device. Content Scramble System (CSS), Content Protection for Recordable Media (CPRM) and Advanced Access Content System (AACS) require the use of HDCP on HDMI when playing back encrypted DVD Video, DVD Audio, HD DVD and Blu-ray Discs. The HDCP repeater bit controls the authentication and switching/distribution of an HDMI signal. According to HDCP Specification 1.2 (beginning with HDMI CTS 1.3a), any system that implements HDCP must do so in a fully compliant manner. HDCP testing that was previously only a requirement for optional tests such as the "Simplay HD" testing program is now part of the requirements for HDMI compliance. HDCP accommodates up to 127 connected devices with up to 7 levels, using a combination of sources, sinks and repeaters. A simple example of this is several HDMI devices connected to an HDMI AV receiver that is connected to an HDMI display. though a fair use and non-disclosure form must usually be signed with a registering agency before use. Connectors There are five HDMI connector types. Type A/B are defined in the HDMI 1.0 specification, type C is defined in the HDMI 1.3 specification, and type D/E are defined in the HDMI 1.4 specification. ; Type A; Standard : The plug (male) connector outside dimensions are 13.9 mm × 4.45 mm, and the receptacle (female) connector inside dimensions are 14 mm × 4.55 mm. measuring only 5.83 mm × 2.20 mm ; Type E; Automotive : The Automotive Connection System has a locking tab to keep the cable from vibrating loose and a shell to help prevent moisture and dirt from corroding the pins. The HDMI alternate mode lets a user connect the reversible USB-C connector with the HDMI source devices (mobile, tablet, laptop). This cable connects to video display/sink devices using any of the native HDMI connectors. This is an HDMI cable, in this case a USB-C to HDMI cable. Cables An HDMI cable is composed of four shielded twisted pairs, with a characteristic impedance of 100 Ω (±15%), plus seven separate conductors. HDMI cables with Ethernet differ in that three of the separate conductors instead form an additional shielded twisted pair (with the CEC/DDC ground as a shield). and certification is difficult to achieve for lengths beyond 13 m. HDMI 1.3 defines two cable categories: Category 1-certified cables, which have been tested at 74.25 MHz (which would include resolutions such as 720p60 and 1080i60), and Category 2-certified cables, which have been tested at 340 MHz (which would include resolutions such as 1080p60 and 4K30). Category 1 HDMI cables are marketed as "Standard" and Category 2 HDMI cables as "High Speed". Category 1 and 2 cables can either meet the required parameter specifications for inter-pair skew, far-end crosstalk, attenuation and differential impedance, or they can meet the required non-equalized/equalized eye diagram requirements. HDMI cables are certified to guarantee a certain level of performance at an Authorized Testing Center (ATC). As of the HDMI 2.2 specification, the following certifications are defined for HDMI cables in consumer applications: Separate certifications also exist for "automotive" Standard and High Speed HDMI cables, which use a different connector with a latching mechanism. Extenders Long cables can cause instability of HDCP and blinking on the screen due to the weakened DDC signal that HDCP requires. An extender can be used to address this instability. An HDMI extender is a single device (or pair of devices) powered with an external power source or from the 5VDC from the HDMI source. • Standard HDMI cables • Active HDMI cables use electronics within the cable to boost the signal and allow for HDMI cables of up to . There is a standard for AV over single-Ethernet-cable, HDBaseT, which is used by some extenders as the on-wire format. HDBaseT has a maximum reach of 100 meters. • HDMI extenders that are based on dual Category 5/Category 6 cable can extend HDMI to . HDMI adopters While earlier versions of HDMI specs are available to the public for download, only adopters have access to the latest standards (HDMI 1.4b/2.1). Only adopters have access to the compliance test specification (CTS) that is used for compliance and certification. Compliance testing is required before any HDMI product can be legally sold. • Adopters have IP rights under Adopter Agreement. • Adopters receive the right to use HDMI logos and trademarks on their products and marketing materials. • Adopters are listed on the HDMI website. • Products from adopters are listed and marketed in the official HDMI product finder database. • Adopters receive more exposure through combined marketing, such as the annual HDMI Developers Conference and technology seminars. HDMI fee structure There are two annual fee structures associated with being an HDMI adopter: • High-volume (more than 10,000 units) HDMI Adopter Agreement per year. • Low-volume (10,000 units or fewer) HDMI Adopter Agreement plus a flat per unit administration fee. The annual fee is due upon the execution of the Adopter Agreement, and must be paid on the anniversary of this date each year thereafter. The royalty fee structure is the same for all volumes. The following variable per-unit royalty is device-based and not dependent on number of ports, chips or connectors: • for each end-user licensed product • if the HDMI logo is used on the product and promotional material, the per-unit fee drops from to . • if HDCP is implemented and HDMI logo is used, the per-unit fee drops from to . Use of HDMI logo requires compliance testing. Adopters need to license HDCP separately. The HDMI royalty is only payable on licensed products that will be sold on a stand-alone basis (i.e., that are not incorporated into another licensed product that is subject to an HDMI royalty). For example, if a cable or IC is sold to an adopter who then includes it in a television subject to a royalty, then the cable or IC maker would not pay a royalty, and the television manufacturer would pay the royalty on the final product. If the cable is sold directly to consumers, then the cable would be subject to a royalty. ==Versions==

(in Silicon Valley) HDMI devices and cables are designed based on the HDMI Specification, a document published by HDMI Licensing (through version 1.4b) or the HDMI Forum (from version 2.0 onward). The HDMI Specification defines the minimum baseline requirements that all HDMI devices must adhere to for interoperability, as well as a large set of optional features that HDMI devices may support. The specification is periodically updated to add clarifications or define new capabilities that HDMI devices may implement. Each new version of the specification expands the list of possible features, but does not mandate support for new features in all devices or establish any "classes" of HDMI products which must support certain capabilities. Version numbers do not refer to classes or tiers of products with certain levels of feature support, and as such, HDMI specification "version numbers" are not a method of describing support for specific features or describing the capabilities of an HDMI device or cable. In 2009, HDMI Licensing banned the use of "version numbers" in labeling HDMI products. Instead, HDMI devices should explicitly declare which features and capabilities they support. For HDMI cables, a speed rating system was established since feature support is not dependent on the cable (apart from inline Ethernet and ARC); the cable only affects the maximum possible speed of the connection. Version 1.1 HDMI 1.1 was released on May 20, 2004, and added support for DVD-Audio. Version 1.2 HDMI 1.2 was released on August 8, 2005, and added the option of One Bit Audio, used on Super Audio CDs, at up to 8 channels. To make HDMI more suitable for use on PC devices, version 1.2 also removed the requirement that only explicitly supported formats be used. It added the ability for manufacturers to create vendor-specific formats, allowing any arbitrary resolution and refresh rate rather than being limited to a pre-defined list of supported formats. In addition, it added explicit support for several new formats including 720p at 100 and 120 Hz and relaxed the pixel format support requirements so that sources with only native RGB output (PC sources) would not be required to support output. HDMI 1.2a was released on December 14, 2005 and fully specifies Consumer Electronic Control (CEC) features, command sets and CEC compliance tests. Like previous versions, it uses TMDS encoding, giving it a maximum video bandwidth of (sufficient for at 144Hz or at 75Hz). It added support for 10bpc, 12bpc, and 16bpc color depth (30, 36, and 48bit/px), called deep color. It also added support for the xvYCC color space, in addition to the ITU-R BT.601 and BT.709 color spaces supported by previous versions, and added the ability to carry metadata defining color gamut boundaries. It also optionally allows output of Dolby TrueHD and DTS-HD Master Audio streams for external decoding by AV receivers. It incorporates automatic audio syncing (audio video sync) capability. HDMI 1.3a was released on November 10, 2006, and had cable and sink modifications for HDMI type C, source termination recommendations, and removed undershoot and maximum rise/fall time limits. It also changed CEC capacitance limits, and CEC commands for timer control were brought back in an altered form, with audio control commands added. It also added the optional ability to stream SACD in its bitstream DST format rather than uncompressed raw DSD. Version 1.4 HDMI 1.4 was released on June 5, 2009, and first came to market after Q2 of 2009. Retaining the bandwidth of the previous version, HDMI 1.4 defined standardized timings to use for 40962160 at 24Hz, 38402160 at 24, 25, and 30Hz, and added explicit support for 19201080 at 120Hz with CTA-861 timings. It also added an HDMI Ethernet Channel (HEC) that accommodates a Ethernet connection between the two HDMI connected devices so they can share an Internet connection, introduced an audio return channel (ARC), 3D Over HDMI, a new Micro HDMI Connector, an expanded set of color spaces with the addition of sYCC601, Adobe RGB and Adobe YCC601, and an Automotive Connection System. HDMI 1.4 defined several stereoscopic 3D formats including field alternative (interlaced), frame packing (a full resolution top-bottom format), line alternative full, side-by-side half, side-by-side full, 2D + depth, and 2D + depth + graphics + graphics depth (WOWvx). HDMI 1.4 requires that 3D displays implement the frame packing 3D format at either 720p50 and 1080p24 or 720p60 and 1080p24. HDMI 1.4a has defined mandatory 3D formats for broadcast, game, and movie content. containing only minor clarifications to the 1.4a document. HDMI 1.4b is the last version of the standard that HDMI LA is responsible for. All later versions of the HDMI Specification are produced by the HDMI Forum, created on October 25, 2011. Version 2.0 HDMI 2.0, referred to by some manufacturers as HDMI UHD, was released on September 4, 2013. HDMI 2.0 uses TMDS encoding for video transmission like previous versions, giving it a maximum video bandwidth of . This enables HDMI 2.0 to carry 4K video at 60 Hz with 24 bit/px color depth. Other features of HDMI 2.0 include support for the Rec. 2020 color space, up to 32 audio channels, up to 1536 kHz audio sample frequency, dual video streams to multiple users on the same screen, up to four audio streams, 4:2:0 chroma subsampling, 25 fps 3D formats, support for the 21:9 aspect ratio, dynamic synchronization of video and audio streams, the HE-AAC and DRA audio standards, improved 3D capability, and additional CEC functions. HDMI 2.0a was released on April 8, 2015, and added support for High Dynamic Range (HDR) video with static metadata. HDMI 2.0b was released March 2016. HDMI 2.0b initially supported the same HDR10 standard as HDMI 2.0a as specified in the CTA-861.3 specification. Version 2.1 HDMI 2.1 was officially announced by the HDMI Forum on January4, 2017, and was released on November 28, 2017. It adds support for higher resolutions and higher refresh rates, including 4K 120Hz and 8K 60Hz. HDMI 2.1 also introduces a new HDMI cable category called Ultra High Speed (referred to as 48G during development), which certifies cables at the new higher speeds that these formats require. Ultra High Speed HDMI cables are backwards compatible with older HDMI devices, and older cables are compatible with new HDMI 2.1 devices, though the full bandwidth is only supported with the new cables. Some systems may not be able to use HDMI 2.1 because the HDMI Forum is preventing its use in open source implementations (such as Linux open source drivers). Users of those systems may need to use DisplayPort instead to access high resolutions and speeds. The following features were added to the HDMI 2.1 Specification: • Maximum supported format is 10K at 120Hz • Dynamic HDR for specifying HDR metadata on a scene-by-scene or even a frame-by-frame basis • Note: While HDMI 2.1 did standardize transport of dynamic HDR metadata over HDMI, in actuality it only formalized dynamic metadata interfaces already utilized by Dolby Vision and HDR10+ in HDMI 2.0, which is why neither Dolby Vision nor HDR10+ require HDMI 2.1 to function properly. • Display Stream Compression (DSC) 1.2 is used for video formats higher than 8K with 4:2:0 chroma subsampling • High Frame Rate (HFR) for 4K, 8K, and 10K, which adds support for refresh rates up to 120Hz • Enhanced Audio Return Channel (eARC) for object-based audio formats such as Dolby Atmos and DTS:X • Enhanced refresh rate and latency reduction features: • Variable Refresh Rate (VRR) reduces or eliminates lag, stutter and frame tearing for more fluid motion in games • Quick Media Switching (QMS) for movies and video eliminates the delay that can result in blank screens before content begins to be displayed • Quick Frame Transport (QFT) reduces latency by bursting individual pictures across the HDMI link as fast as possible when the link's hardware supports more bandwidth than the minimum amount needed for the resolution and frame rate of the content. With QFT, individual pictures arrive earlier and some hardware blocks can be fully powered off for longer periods of time between pictures to reduce heat generation and extend battery life. • Auto Low Latency Mode (ALLM)Allows the HDMI source device to direct the display to optimize either for low latency at the expense of image quality or for image quality at the expense of latency, presumably according to the content. Video formats that require more bandwidth than (4K 60Hz 8bpc RGB), such as 4K 60Hz 10bpc (HDR), 4K 120Hz, and 8K 60Hz, may require the new "Ultra High Speed" or "Ultra High Speed with Ethernet" cables. 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 (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. Version 2.2 HDMI 2.2 was announced on January 6, 2025, it was released on June 25, 2025. The maximum allowed bit rate is increased to and Latency Indication Protocol (LIP) support is added for improving audio and video synchronization. Version comparison Main specifications ==Resolution and refresh frequency limits==

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 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 and HD DVD video (version 1.0) • Consumer Electronic Control (CEC) (version 1.0) • DVD-Audio (version 1.1) • Super Audio CD (DSD) (version 1.2) • Auto Lip-Sync Correction (version 1.3) • Dolby TrueHD / DTS-HD Master Audio bitstream capable (version 1.3) • Updated list of CEC commands (version 1.3a) • 3D video (version 1.4) • Hybrid log–gamma (HLG) HDR EOTF (version 2.0a) 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. ==Applications==

Blu-ray Disc and HD DVD players Blu-ray Disc and HD DVD, introduced in 2006, offer high-fidelity audio features that require HDMI for best results. HDMI 1.3 can transport Dolby Digital Plus, Dolby TrueHD, and DTS-HD Master Audio bitstreams in compressed form. 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 codecs internally and can output LPCM audio over HDMI. Multichannel LPCM can be transported over an HDMI connection, and as long as the AV receiver implements multichannel LPCM audio over HDMI and implements HDCP, 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 often include an HDMI interface for playback or even live preview, the image processor and the video processor of cameras usable for uncompressed video must be able to deliver the full image resolution at the specified frame rate in real time without any missing frames causing jitter. In addition, to be used as a video source, such as for streaming or switching, the camera must also be capable of removing the UI elements from the image. Therefore, usable uncompressed video out of HDMI without the device's UI elements is often called "clean HDMI". Personal computers Personal computers (PCs) with a DVI interface are capable of video output to an HDMI-enabled monitor. For example, Intel's motherboard chipsets since the 945G and NVIDIA's GeForce 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 can drive 8-channel LPCM audio over HDMI if the video card has the necessary hardware and implements the Advanced Linux Sound Architecture (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 HDCP, 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 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. 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 announced the ATI Radeon HD 5000 series 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. In December 2010, it was announced that several computer vendors and display makers including Intel, AMD, Dell, Lenovo, Samsung, and LG would stop using LVDS (actually, FPD-Link) from 2013 and legacy DVI and VGA connectors from 2015, replacing them with DisplayPort 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, most consoles support HDMI. Video game consoles that support HDMI include the Xbox 360 (except most pre-2007 models) (1.2a), Xbox One (1.4b), Xbox One S (2.0a), Xbox One X (2.0b), PlayStation 3 (1.3a), PlayStation 4 (1.4b), PlayStation 4 Pro (2.0a), Wii U (1.4a), Nintendo Switch (1.4b), Nintendo Switch (OLED model) (2.0a), Xbox Series X and Series S (2.1), PlayStation 5 (2.1), And Nintendo Switch 2 (2.1). Tablet computers Some tablet computers 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 models have a special A/V adapter that converts Apple's Lightning connector 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 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, VGA, RCA, etc.) by means of a digital-to-analog converter or AV receiver, 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 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 30 Hz and CEC. Previously, the similar DisplayPort 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. as there are no known products using this protocol, reducing its relevance in the current market. This will reduce consumer confusion as DisplayPort Alternate Mode is the primary video protocol of choice over USB-C. ==Relationship with DisplayPort==

The DisplayPort audio/video interface was introduced in May 2006 by the Video Electronics Standards Association (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). 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), 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 HDCP 2.2. Revision 1.4 added Display Stream Compression (DSC), support for the BT.2020 color space, and HDR10 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. DisplayPort is royalty-free, though patent pool 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) is required to convert the signal to HDMI. MHL is developed by a consortium 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. 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 HDCP encrypted uncompressed high-definition video and eight-channel surround sound), 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 USB-C 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 60 Hz ( 4:2:2) with a bandwidth of in PackedPixel mode. 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). Display Stream Compression (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. ==HDMI Forum==

On October 25, 2011, the HDMI Forum was established by the HDMI founders to create an open, nonprofit industry consortium so that interested companies can participate in the development of the HDMI specification. All members of the HDMI Forum have equal voting rights, may participate in the Technical Working Group, and if elected can be on the Board of Directors. There is no limit to the number of companies allowed in the HDMI Forum though companies must pay an annual fee of US$15,000 with an additional annual fee of $5,000 for those companies that serve on the Board of Directors. The Board of Directors is made up of 11 companies who are elected every two years by a general vote of HDMI Forum members. All future developments of the HDMI specification take place in the HDMI Forum and are built upon the HDMI 1.4b specification. ==See also==