HDMI 2.1a 是最新的HDMI标准，支持更高的视频分辨率、帧速率和带宽能力。它还配备了一系列新功能，为游戏玩家提供了巨大的改进，包括减少屏幕延迟和卡顿。
在本文中，我们将解释HDMI 2.1a是什么，然后深入了解它的功能，以便您了解对这项新技术的期望。
什么是 HDMI 2.1a？
高清多媒体接口(High-Definition Multimedia Interface)( HDMI ) 是标准音频/视频接口之一，允许将视频从源设备传输到显示器。
HDMI 2.1a预计在 2022 年早些时候发布，是 HDMI 的新标准。它拥有一系列升级，包括支持更高分辨率、改进的帧速率、HDR视频和更高的带宽容量。
HDMI 2.1a 使用与以前的(HDMI)HDMI版本相同的连接器，并且具有向后兼容性。
HDMI 2.1a 由 HDMI Forum(HDMI 2.1a is developed by the HDMI Forum) , Inc.开发，该论坛由 90 家世界领先的电子制造商、电影工作室、测试实验室和视频服务提供商组成。HDMI 2.1a 在CES 2022上发布。
HDMI 2.1a有哪些新功能(New Features)？
HDMI 2.1a 具有一系列可提高视频和游戏质量的新功能，例如支持更高的分辨率和刷新率(refresh rates)。
- 更高分辨率：(Higher resolutions: ) HDMI 2.1a 支持8K 60Hz和 4K 120Hz，以及 5K 和 10K 分辨率（用于商业 AV）。
- 动态 HDR：(Dynamic HDR: )动态高动态范围(Dynamic High Dynamic Range)( HDR ) 可提高对比度和视觉质量。HDMI 2.1a 支持静态和动态HDR元数据的多种格式，包括HDR10+（HDR10 的动态版本）(HDR10)。这是一个大新闻，因为与现有的专有HDR格式（如杜比视界(Dolby Vision)）不同（这意味着制造商需要支付许可费才能使用它），HDR10+没有许可费。
- 基于源的色调映射 (SBTM)：(Source-Based Tone Mapping (SBTM): )通常，色调映射由显示器执行。SBTM是一种HDR功能，它使用内容源（例如游戏机或计算机）来执行色调映射背后的处理。这有助于显示器在不同的SDR、HDR和动态HDR输入下表现得更好。
- 超高速 HDMI 电缆：(Ultra High-Speed HDMI Cable: )新的HDMI 2.1规范附带了一个新的电缆规范，其带宽能力增加了高达 48Gbps（高于HDMI 2.0的 18Gbps ）。
- HDMI 增强型音频回传通道 (eARC)：(HDMI Enhanced Audio Return Channel (eARC): ) e ARC取代了之前的音频回传通道(Audio Return Channel)( ARC )，为多个连接的组件提供了更大的音频优化。它支持高达 192kHz、24 位未压缩 5.1、7.1 或 32 声道音频（包括杜比全景声(Dolby Atmos)）的高比特率音频格式。使用 e ARC，用户可以将所有设备连接到他们的电视，然后将单个HDMI连接到他们的条形音箱以获得无损、高质量的音频，从而简化设置。
- 可变刷新率 (VRR)：VRR(Variable Refresh Rate (VRR): )是(VRR)新的增强游戏功能之一，它通过允许游戏机尽可能快地传输帧来减少屏幕延迟和卡顿，从而实现更流畅的游戏体验。
- 自动低延迟模式 (ALLM)：(Auto Low Latency Mode (ALLM): )ALLM根据视频源自动设置理想的延迟设置。对于游戏机或计算机，将设置低延迟模式以实现无延迟观看。对于视频，将禁用低延迟以优化视频质量。
- 快速帧传输 (QFT)：(Quick Frame Transport (QFT): )另一个游戏功能，QFT通过提高通过电缆传输帧的速度来帮助减少延迟。这减少了显示延迟并提高了响应能力。
- 快速媒体切换 (QMS)：(Quick Media Switching (QMS): )QMS使用VRR技术允许在不同帧速率的视频之间进行即时切换。这有助于消除以前HDMI版本常见的 A/V 中断。
- HDMI 电缆电源：(HDMI cable power: ) HDMI 2.1 电缆可以为支持的设备传输电源，这意味着不需要单独的电源线。
有关详细信息，请参阅HDMI.org 上 的HDMI 规格页面。(HDMI specifications page)
HDMI 2.1a 是 A/V 的未来吗？
HDMI已迅速成为行业标准的 A/V 接口。与(Compared with other interfaces)DisplayPort等其他接口相比，HDMI支持的设备范围更广。但是您需要尽快升级吗？
目前， HDMI 2.1a(HDMI 2.1a)的主要优势是支持更高的视频和音频分辨率（例如能够在Sony Playstation 5或Xbox Series X上以 4K 分辨率和 120Hz 播放）。因此，除非您需要 4K120 或者您已经购买了 8K 电视，否则几乎没有理由立即升级。
What Is HDMI 2.1a and How Is It Different?
HDMI 2.1a is the latest HDMI standard, supporting higher video resolυtions, framе ratеs, and bandwidth capabilities. It also comes with a stack of new features which offer drastic improvements for gamers, including reduced screen lag and stυttering.
In this article, we’ll explain what HDMI 2.1a is and then dive into its features so you know what to expect from this new technology.
What Is HDMI 2.1a?
High-Definition Multimedia Interface (HDMI) is one of the standard audio/video interfaces allowing video transmission from a source device to a display.
With the expected release date earlier in 2022, HDMI 2.1a is HDMI’s new standard. It boasts a suite of upgrades, including support for higher resolutions, improved frame rates, HDR video, and much higher bandwidth capacity.
HDMI 2.1a uses the same connector as previous HDMI versions and has backward compatibility.
HDMI 2.1a is developed by the HDMI Forum, Inc., a group of 90 of the world’s leading electronics manufacturers, movie studios, test labs, and video service providers. HDMI 2.1a was announced at CES 2022.
What Are the New Features of HDMI 2.1a?
HDMI 2.1a has a stack of new features that improve the quality of video and gaming, such as support for much higher resolutions and refresh rates.
- Higher resolutions: HDMI 2.1a supports 8K 60Hz and 4K 120Hz, as well as 5K and 10K resolutions (for commercial AV).
- Dynamic HDR: Dynamic High Dynamic Range (HDR) offers an increase in contrast and visual quality. HDMI 2.1a supports multiple formats for both static and dynamic HDR metadata, including HDR10+ (the dynamic version of HDR10). This is big news because unlike existing HDR formats such as Dolby Vision which are proprietary (meaning manufacturers need to pay licensing fees to use it), HDR10+ has no licensing fees.
- Source-Based Tone Mapping (SBTM): Generally, tone mapping is performed by the display. SBTM is an HDR feature that uses the content source (such as the game console or computer) to perform the processing behind tone mapping. This helps the display perform better with varying SDR, HDR, and dynamic HDR inputs.
- Ultra High-Speed HDMI Cable: The new HDMI 2.1 specification comes with a new cable specification that has an increased bandwidth capability of up to 48Gbps (up from 18Gbps with HDMI 2.0).
- HDMI Enhanced Audio Return Channel (eARC): eARC replaces the previous Audio Return Channel (ARC), providing greater audio optimization for multiple connected components. It supports high-bitrate audio formats up to 192kHz, 24-bit in uncompressed 5.1, 7.1, or 32-channel audio (including Dolby Atmos). With eARC, users can connect all devices to their TV then run a single HDMI to their soundbar for lossless, high-quality audio, which simplifies setups.
- Variable Refresh Rate (VRR): One of the new enhanced gaming features, VRR reduces screen lag and stutter for smoother gameplay by allowing the gaming console to deliver frames as fast as it can.
- Auto Low Latency Mode (ALLM): ALLM automatically sets the ideal latency setting depending on the video source. For gaming consoles or computers, low latency mode will be set to enable lag-free viewing. For video, low latency will be disabled so that video quality is optimized.
- Quick Frame Transport (QFT): Another gaming feature, QFT helps reduce latency by increasing the speed of transporting frames via the cable. This reduces the display lag and improves responsiveness.
- Quick Media Switching (QMS): QMS uses VRR technology to allow instant changes between videos with different frame rates. This helps to eliminate A/V blackouts that were common with previous HDMI versions.
- HDMI cable power: HDMI 2.1 cables can transfer power to supported devices, meaning a separate power cable is unnecessary.
For more information, see the HDMI specifications page on HDMI.org.
Is HDMI 2.1a The Future of A/V?
HDMI has quickly become the industry standard A/V interface. Compared with other interfaces like DisplayPort, HDMI supports a far wider range of devices. But do you need to upgrade as soon as possible?
Right now, the main benefit of HDMI 2.1a is support for higher video and audio resolutions (such as being able to play at 4K resolution and 120Hz on a Sony Playstation 5 or Xbox Series X). So, unless you need 4K120 or you’ve bought an 8K TV, there’s little reason to upgrade immediately.
