SMPTE has published ST 2094-50:2026, a new member of the ST 2094 dynamic-metadata family focused on broadcast and mixed-source presentation. The document became available on 28 August and is identified as Application #5 for dynamic colour-volume transformation.
The system defines an explicit HDR Reference White in embedded metadata and provides parameters for adaptive tone mapping, alternate image headroom, component mixing and gain curves. The aim is to give a compositor or display pipeline enough information to combine HDR and SDR video, graphics, text and still images predictably.
This addresses a practical problem in modern television and device workflows: an HDR programme may contain SDR inserts, score graphics, captions and user-interface elements, while the destination displays offer very different peak luminance. A common metadata model can reduce vendor-specific interpretation and preserve the intended relationship between diffuse white and highlights.
Publication makes the normative standard available, but interoperability still depends on implementations. Adoption by encoders, compositors, operating systems and displays, carriage mappings and conformance test material will determine how quickly Application #5 becomes usable end to end.
