Overview of HDMI 2.1
HDMI® Specification 2.1 is the most recent update of the HDMI specification and supports a range of higher video resolutions and refresh rates including 8K60 and 4K120, and resolutions up to 10K. Dynamic HDR formats are also supported, and bandwidth capability is increased up to 48Gbps.
Supporting the 48Gbps bandwidth is the new Ultra High Speed HDMI Cable. The cable ensures high-bandwidth dependent features are delivered including uncompressed 8K video with HDR. It features exceptionally low EMI (electro-magnetic interference) which reduces interference with nearby wireless devices. The cable is backwards compatible and can be used with the existing installed base of HDMI devices.
Q: Where can I download the HDMI 2.1 Specification?
A: The HDMI 2.1 Specification can be downloaded from the HDMI Adopter Extranet.
Q: How do you license the HDMI 2.1 Specification?
A: In order to license the HDMI 2.1 Specification, you must first become an HDMI Adopter and then sign an addendum to the HDMI Adopter Agreement which provides a license to the HDMI 2.1 Specification.
Q: Can non-HDMI Adopters license only the HDMI 2.1 Specification?
A: Companies wishing to use the HDMI 2.1 specification must become an HDMI Adopter and also sign the HDMI 2 Adopter Addendum. They will have access to HDMI 1.4b and HDMI 2.1 Specifications.
Q: If I am a current HDMI 1.4b Adopter, do I have to license HDMI 2.1 Specification?
A: No, Adopters have the option to only license 1.x. HDMI Adopters can sign the HDMI 2 Adopter Addendum to gain access to the HDMI 2.1 specification.
Q: Do HDMI 2.0 Adopters automatically get access to HDMI 2.1 Specification?
A: Yes, it is licensed under the Version 2 addendum.
Q: Will current Adopters be required to pay an additional Annual Fee if they choose to adopt the HDMI 2.1 Specification?
Q: Will there be any new royalty and/or increase in current royalties for products that implement HDMI 2.1 Specification features?
A: No, there is no additional royalty for implementing the HDMI 2.1 Specification.
Q: What is the relationship of HDMI Specification 2.1 to HDMI 2.0b and 1.4b Specifications?
A: The HDMI 2.1 Specification supersedes 2.0b and 2.1 continues to make reference to, and rely upon, HDMI 1.4b Specification.
Q: Is HDMI 2.1 Specification backwards compatible with previous versions of the specification?
High Video Resolutions
Q: Will 8K@60 or 4K@120 require a new cable?
A: Yes, in order to ensure performance and compatibility the Ultra High Speed HDMI Cable is required.
Q: What are the supported resolutions and frame rates?
Q: Is compression used to achieve those resolutions and frame rates?
A: The specification supports both uncompressed and compressed modes. Manufacturers can implement either or both modes. The designations are:
- 4K120A – supports uncompressed mode
- 4K120B – supports compressed mode
- 4K120AB – supports both
- 8K60A – supports uncompressed mode
- 8K60B – supports compressed mode
- 8K60AB – supports both
Q: How do I identify which modes are supported in my products?
A: Manufacturers may use the designations indicated above (e.g. 8K60A, 8K60B, 8K60AB) in their product marketing, advertising, user guides, packaging, website, and on-product.
Q: What type of compression is supported?
A: The specification incorporates VESA DSC 1.2a link compression, which is a visually lossless compression scheme. DSC also can be used to obtain higher resolutions than 8K60/4:2:0/10-bit color, such as 8K60 RGB, 8K120 and even 10K120.
Q: What colorimetry is supported?
A: HDMI 2.1 Specification supports the latest color spaces including BT.2020 with 10, 12, and 16 bits per color component.
Ultra High Speed HDMI Cable
Q: What is an Ultra High Speed HDMI Cable?
A: The Ultra High Speed HDMI Cable is the first cable defined by the HDMI Forum. Ultra High Speed HDMI Cables comply with stringent specifications designed to ensure support for high resolution video modes such as 4Kp50/60/100/120 and 8Kp50/60 as well as new features such as eARC and VRR. Ultra High Speed HDMI Cables exceed the requirements of the latest international EMI standards to significantly reduce the probability of interference with wireless services such as Wi-Fi.
Q: Is the Ultra High Speed HDMI Cable a Category 3 cable?
Q: Is this cable required for delivering HDMI 2.1 Specification features?
A: The cable is the best way to ensure that high-bandwidth dependent features are delivered including the enhanced video and audio performance, and accounting for the new EMI characteristics
Q: What cable(s) do I need to make use of the eARC feature?
A: Ultra High Speed HDMI Cables are designed to support the new eARC feature in addition to the highest resolution video modes. The Standard HDMI Cable with Ethernet and the High Speed HDMI Cable with Ethernet will also support eARC.
Q: When will I be able to purchase an Ultra High Speed HDMI Cable?
A: Schedules for the availability of Ultra High Speed HDMI Cables are determined by the manufacturers of the cables. Manufacturers will be able to ship these cables once the HDMI 2.1 Compliance Test Specification (CTS) is available and a cable has passed compliance testing. The HDMI Forum is actively working on development of these tests and expects them to be available in 1H 2018.
Q: Will existing HDMI High Speed Cables deliver the HDMI 2.1 features also?
A: Existing HDMI High Speed Cables with Ethernet can only deliver some of the new features, and the new Ultra High Speed HDMI Cable is the best way to connect HDMI 2.1 enabled devices to ensure delivery of all the features.
Q: What connectors does the Ultra High Speed HDMI Cable use?
A: It is compatible with HDMI connectors Types A, C and D.
Q: Does the Ultra High Speed HDMI Cable have an Ethernet channel?
A: Yes, it supports the HDMI Ethernet Channel.
Q: Can the Ultra High Speed HDMI Cable work with existing HDMI devices?
A: The cable is backwards compatible and can be used with all existing HDMI devices.
Q: What is the maximum length of this cable?
A: The specification does not indicate a cable length. Cable length depends on the cable manufacturer. It is likely the maximum lengths for passive cables will be approximately 2 to 3 meters.
Q: Are active cables supported in the specification?
A: The specification permits wire, passive, active, and converter Category 3 cable assemblies.
Q: Will these cables require a new cable name logo for their packaging?
A: Yes, just like existing HDMI cables they will have an official Cable Name Logo design and colors, and requirements for on-cable printing. Details will be available in a separate document available on the HDMI.org website.
Q: Does Dynamic HDR require the new Ultra High Speed HDMI Cable?
A: No, but it will be necessary to enable 4K120 and 8K60 video with HDR due to the high bandwidth required by these resolutions and refresh rates.
Q: Which HDR formats does the specification support?
A: It supports various static and dynamic HDR solutions in the market.
Q: Is Dynamic HDR accessible via a firmware upgrade?
A: Manufacturers may or may not be able to enable Dynamic HDR with a firmware upgrade. Contact the manufacturer of your product to see if this is possible.
Q: Will this work with any HDMI cable?
A: This works with HDMI High Speed Cables with Ethernet and the new Ultra High Speed HDMI Cable.
Q: Is eARC available through a firmware upgrade?
A: Generally speaking, no. Check with the manufacturer of your product to confirm.
Q: What audio formats are supported?
A: The latest high-bitrate audio formats are supported including DTS Master, DTS:X, Dolby TrueHD, Dolby Atmos and more.
Q: Will the existing ARC-enabled products work with new products that use eARC?
A: Maybe. Manufacturers can produce products that are compatible with both eARC and ARC. However, eARC is not defined to be backwards compatible with ARC.
Enhanced Refresh Rate Features
Q: Are these primary for gaming applications?
A: Certain aspects are better suited for gaming, but it depends on how the manufacturers implement the features. For example, for better gaming, Variable Refresh Rate (VRR) that synchs up source and display with continually changing refresh rate, and Quick Frame Transport (QFT) that allows frames to transmit faster from the source, both allow for smoother, no-lag, and no screen tearing gaming experiences.
Q: How is video or movie viewing any better?
A: When you switch between sources and their content sometimes there is a lag or dead screen while devices change resolutions, refresh rates or TV viewing modes; but Quick Media Switching (QMS) switches and sets those automatically and very quickly so viewing is uninterrupted and smooth.
Q: Can products have a combination of these features?
A: Yes, but it depends on each manufacturer’s implementation, so it is necessary to carefully check their specifications and marketing materials.
Q: Are these features backwards compatible or do all the components have to be HDMI 2.1 enabled?
A: The devices have to be 2.1 enabled and also have the same feature capabilities enabled on both the source and display.
Q: What is the testing policy for HDMI 2.1 products?
A: All products must comply with Version 2.1 of the HDMI Specification and the HDMI 2.1 Compliance Test Specification (CTS); and until the CTS is available and a product has passed compliance testing a product cannot claim to be 2.1 compliant or market that it supports 2.1 features.
Q: When will the HDMI 2.1 Compliance Test Specification be available?
A: The HDMI 2.1 Compliance Test Specification (CTS) will be published in stages during Q1-Q3 2018.
Q: When will ATCs start to provide 2.1 testing services?
A: Each individual ATC will decide on when to offer HDMI 2.1 testing services. Please contact your local ATC for more information.
HDMI 2.1 Specification was developed by the HDMI Forum’s Technical Working Group. For more information about the HDMI Forum and how to become a member click here
HDMI Specification 2.1 feature highlights include:
- Higher video resolutions support a range of high resolutions and faster refresh rates including 8K60Hz and 4K120Hz for immersive viewing and smooth fast-action detail. Resolutions up to 10K are also supported for commercial AV, and industrial and specialty usages.
- Dynamic HDR support ensures every moment of a video is displayed at its ideal values for depth, detail, brightness, contrast and wider color gamuts—on a scene-by-scene or even a frame-by-frame basis.
- The Ultra High Speed HDMI Cable supports the 48G bandwidth for uncompressed HDMI 2.1 feature support. The cable also features very low EMI emission and is backwards compatible with earlier versions of the HDMI Specification and can be used with existing HDMI devices.
- eARC simplifies connectivity, provides greater ease of use, and supports the most advanced audio formats and highest audio quality. It ensures full compatibility between audio devices and upcoming HDMI 2.1 products.
- Enhanced refresh rate features ensure an added level of smooth and seamless motion and transitions for gaming, movies and video. They include:
- Variable Refresh Rate (VRR) reduces or eliminates lag, stutter and frame tearing for more fluid and better detailed gameplay.
- Quick Media Switching (QMS) for movies and video eliminates the delay that can result in blank screens before content is displayed.
- Quick Frame Transport (QFT) reduces latency for smoother no-lag gaming, and real-time interactive virtual reality.
- Auto Low Latency Mode (ALLM) allows the ideal latency setting to automatically be set allowing for smooth, lag-free and uninterrupted viewing and interactivity.
Version 2.1 of the HDMI Specification is backward compatible with earlier versions of the Specification and is available to all HDMI 2.0 Adopters.