Dec 14, 2021 21:00:00

Is it false to advertise a monitor that only supports HDMI 2.0 as 'HDMI 2.1 compatible'?

HDMI (High-Definition Multimedia Interface) is a communication standard that allows you to send video and audio together on a single cable, and the transmission speed, video resolution, frame rate, and supported options vary greatly depending on the version. TFT Central, which handles news related to video equipment, said, 'As of December 2021, the LCD display that claims to be compatible with the latest version of HDMI 2.1 was actually only compatible with the old standard HDMI 2.0.' We are investigating.

When HDMI 2.1 Isn't HDMI 2.1 --The Confusing World of the Standard, 'Fake HDMI 2.1' and Likely Future Abuse --TFTCentral
https://tftcentral.co.uk/articles/when-hdmi-2-1-isnt-hdmi-2-1

HDMI 2.1 is a standard announced in 2017. The bandwidth, which was 18 Gbps with HDMI 2.0, has been expanded to 48 Gbps with HDMI 2.1, and along with this, 4K / 120Hz and 8K / 60Hz video can now be transmitted with HDMI 2.1, as well as variable refresh rate (VRR) and automatic low latency. Now also supports mode (ALLM).

What will change from 'HDMI 2.0' to 'HDMI 2.1'? --GIGAZINE

TFT Central investigated the 24.5 inch liquid crystal display XMMNT245HF2 with a refresh rate of 240Hz released by Xiaomi in November 2021, 'Achieving a refresh rate of 240Hz at HD (1080p) resolution' in the specification column of the official website. 'The product specification has one DisplayPort 1.2 port and two HDMI 2.1 ports,' it said.

However, at the bottom of the specification column, 'Due to the subdivision of the HDMI certification standard, HDMI 2.1 has the same bandwidth as HDMI 2.0, depending on the transmission protocol, the

TMDS (Transition Minimized Differential Signaling) method and FRL ( It is classified into two types: Fixed Rate Link) method. The HDMI 2.1 interface of this product supports TMDS method, and the maximum resolution supported by this product is 1920 x 1080 pixels, and the maximum refresh rate is 240Hz. ' It was written small.

In response to this note, TFT Central commented, 'It seemed like we were promoting a device that had only HDMI 2.0 capabilities with the touch of'new HDMI 2.1'.' He contacted HDMI.org, the management organization for the 'TMDS Protocol' HDMI license mentioned by Xiaomi.

The answers that TFT Central got from HDMI.org are:

1: The 'HDMI 2.0' standard no longer exists and is not certified, so you should not claim that your device is 2.0 compliant.
2: HDMI 2.0 features are a subset of HDMI 2.1.
3: All new features related to HDMI 2.1 are optional.
4: If you claim that your device is HDMI 2.1 compliant, you need to specify 'what features it supports' to avoid confusion.

In the context of HDMI.org, 'should be labeled as HDMI 2.1, even if it only provides HDMI 2.0 functionality.' In other words, since HDMI 2.0 certification has been discontinued, it is possible that there is only HDMI 2.0 equivalent performance behind the appeal of 'HDMI 2.1 support'. TFT Central says, 'I think this is a very bad way to authenticate something. What's wrong with authenticating a device that only has HDMI 2.0 capabilities as an HDMI 2.0 capable device?' He argues that certification should define a baseline.

The port on Xiaomi's XMM NT245HF2, which was the subject of the survey, has no features beyond HDMI 2.0, but is advertised to consumers as 'HDMI 2.1 compatible'. However, the spec display including the cautionary note is not false in light of the definition of the HDMI license administrator. TFT Central says, 'Of course, the product says'up to 1080p / 240Hz', so buyers wouldn't expect to see 4K / 120Hz video supported by HDMI 2.1, but the VRR included in HDMI 2.1. It is possible to misunderstand that it also supports ALLM and ALLM. '

For example, if your LCD display that supports '4K resolution' and 'refresh rate above 120Hz' has only an HDMI 2.0 port, you can either limit the color depth to 8bit or use 4: 2 chroma subsampling. Must be limited to 0. TFT Central points out that 'Asus's gaming monitor ROG Swift PG32UQX fits exactly the above analogy, but at least Asus says it's an HDMI 2.0 port by design, revealing its limitations.' increase.

However, TFT Central pointed out that most of the products on the market ignore the definition of HDMI.org and continue to use the HDMI 2.0 notation, saying, 'In fact, the HDMI 2.0 notation continues to be used. I think that's a good thing. We want the HDMI 2.0 display to continue to be used, rather than the HDMI 2.1 name being abused. ' 'Ideally, it's desirable that the HDMI 2.0 display continues to be used, but the HDMI.org guidance seems to go against this,' he said.