Texts posted about SBTM have already been removed, but they can still be read via services like Google Cache. In the segment that has since disappeared, source-based tone mapping is mentioned as a possible specification for hdmi 2.1a, which could be required of media carriers as well as monitors and cables.

Additionally, the Licensing Office of the HDMI Standard has indicated that it is often expected that SBTM can still be added to HDMI 2.1 devices for each firmware update.

For HDMI 2.1 “medium” certification, imaging equipment must be capable of displaying 8k resolution at 60Hz (or 4k resolution at 120Hz) with a bandwidth of at least 48Gbps, including support for dynamic range of HDR.

In general, SBTM provides an additional information channel on top of the known HDR image range. In addition to a larger color spectrum (at least 10-bit depth), this video signal can also indicate which areas of the screen should be brighter or less bright. In theory, this principle should make it possible to combine both HDR and SDR together on a single screen – although the starting point is initially more realistic contrasts.

The overall idea of ​​tone mapping has been around for quite some time. Including Dolby Vision and HDR10 + They are techniques that actually use varying brightness in the overall image, albeit often determined by the monitor. Under future HDMI 2.1a certification, it will be possible to create an industry-wide standard for this purpose, which can be recognized and supported by both displays and video equipment (including consoles and computers).

The hdmi 2.1a standard is still far from definitive or official, but the appearance of SBTM on the website did not come entirely out of thin air. between partners and customers of the HDMI standard,CES 2022The note was distributed, the content of which may have moved to the public website.