What is the …?
The HDMI Licensing Officer, who is looking for an HDMI standard, has updated HDMI 2.1 to “HDMI 2.1aThis isOptimize image quality for different quality contentsIt is standard for the purpose of making it.
But most people don’t even know the details of HDMI 2.1, right? (Same for me…) Here, I would like to explain the features of HDMI 2.1a in an easy to understand manner based on a US Gizmodo column.
What is HDMI 2.1a?
HDMI 2.1a is an updated version of HDMI 2.1,”Select the tone based on the sourceThe feature is called “.
What is the source of the bass tone set?
So what is the tone mapping based on the source? This is one of the methods of image processing.Match digital signals to the right brightness and color for each TVThing. This enables images with a wide dynamic range to be displayed while preserving detail, contrast, and color even on screens with narrow dynamic range.
Also, with HDMI 2.1a, part of the HDRM mapping can be done not only on the screen, but also on the source side of set-top boxes, computers, game consoles, etc.
What is important?
HDMI 2.1a allows the device on the source side to transmit video signals to make more effective use of the HDR function in the display.
For example, when viewing HDR video or photos, the screen is usually set to ensure that the content meets the limited specifications of the screen. However, the content may contain different levels of HDR signals. This includes not only HDR images, but also SDR (Standard Dynamic Range) images and basic images. This is a common case of picture-in-picture display.
In such cases, the screen generally fixes the brightness and color gamut. However, in source-based tone mapping, the source is optimized for display by sending a video signal optimized for the HDR function of the screen.
When is it useful?
For example, when you open the streaming app, HDR-compatible video thumbnails and SDR video thumbnails will be displayed. The same page may contain a base image. HDMI 2.1a allows streaming devices to send signals to the TV at their full capacity. According to the HDMI Forum, HDMI 2.1a is also designed for computers and game consoles, and may improve image quality even in a multi-window environment where videos and text are displayed at the same time.
Is it still difficult?
The tech talk has been going on for a while, and it looks like my head is going to heat up. The HDMI Licensing Officer website describes HDMI 2.1a as follows:
SBTM (Basic Source Tone Mapping) is particularly useful for displaying HDR and SDR video and graphics in a single image, such as Picture-in-Picture guides and software with built-in video windows. The SBTM also allows PCs and game consoles to automatically generate optimized HDR signals to take full advantage of the display’s HDR capabilities without the user having to manually configure the source device.
Do the source device and monitor both need to support HDMI 2.1a?
Unfortunately yes. According to the HDMI Forum, most TVs can be supported with a firmware update, but it’s up to the manufacturer to support it.
The HDMI Forum states that the HDMI 2.1a specification will be “improved and released” in 2022, scheduled for the first quarter (January-March). Details of this specification shall be disclosed in due course.
