HDMI 2.1a briefly appears on the HDMI LA website with Source-Based Tone Mapping
During a pre-CES briefing, the HDMI Licensing Administrator confirmed there is a new version of the 2.1 standard coming.
The Source-Based Tone Mapping (SBTM) is a feature set to enhance and optimize the HDR experience. The technology requires source and target devices to support the new standard, but HDMI LA expects many devices to receive SBTM firmware update at some point in the future
In short, the SBTM will greatly benefit PC and game uses, such as multiwindowed environments. Since the source device will control the tone mapping, it will allow separate windows to display SDR or HDR optimized content at the same time. The SBTM is not meant to replace existing HDR technologies (such as HDR10, HLG), TFTCental notes, but instead it is meant to enrich the HDR experience by offering a wider range of optimizations for HDR-capable devices.
Source-Based Tone Mapping (SBTM) is a new HDR feature that allows a portion of the HDR mapping to be performed by the Source device instead of the Display device. SBTM is especially useful in cases where HDR and SDR video or graphics are combined together into a single picture, such as picture-in-picture or a program guide with an integrated video window. SBTM also enables PCs and gaming devices to automatically produce an optimized HDR signal in order to maximize the utilization of the display’s HDR capabilities without manual user configuration of the Source device.
— HDMI.org
Recently HDMI LA faced criticism for lack of response to fake ‘HDMI 2.1’ displays now appearing on the Chinese market. The administrator claims that HDMI 2.1 features are not a requirement, which is why manufacturers can now claim partial 2.1 support without actually supporting the most obvious technologies associated with the standard.
It should also be noted that the references to HDMI 2.1a specs can still be found through Google Cache, however, the actual website no longer lists the standard. The reason for the lack of 2.1 references is unknown.
HDMI 2.1a SBTM feature, Source: HDMI.org
Source: TFTCentral