MPEG-H 3D Audio is the open ISO immersive standard, the main alternative to Dolby's AC-4, and the audio system of ATSC 3.0 as deployed in South Korea. It unifies all three audio paradigms in one stream — channels, objects, and scene-based Higher-Order Ambisonics — and is built around interactivity: listeners can adjust dialogue, switch language objects, or rebalance elements at playback. The bitstream (MHAS) carries this metadata to the renderer, which adapts to whatever speakers or headphones are present. Because it is standards-based rather than proprietary, MPEG-H is attractive for broadcasters and music (Sony 360 Reality Audio uses it), though Dolby's ecosystem dominates Western streaming.
