scope:

The present document specifies the object model, reference renderer, bitstream syntax and broadcast extensions for MDA. MDA, short for Multi-Dimension Audio, is a metadata model and bitstream representation of an object-based soundfield for linear content, for use in cinema and broadcast applications.

The presentdocument consists of four main clauses. The metadata clause (Clause 4) provides a metadata model independent of (bitstream) representation, with a strong emphasis on cinematic content. Clause 5 specifies a reference renderer, providing semantics for the MDA metadata model. Clause 6 specifies a preferred bitstream representation of the MDA metadata model. Note that the metadata model allows for more than one bitstream representation. Finally, Clause 7 specifies an extension of the core MDA model to include metadata and bitstream elements specifically suited for broadcast content. This Clause includes among others metadata for Loudness, Higher Order Ambisonics and Interactivity.

Unless otherwise stated, MDA metadata are specified using Unified Modeling Language [4].

Note that the MDA core metadata, reference renderer and bitstream documents have been submitted to SMPTE 25CSS "Immersive Sound Model and Bitstream" [i.2] for consideration towards an interoperable immersive sound model and bitstream for cinematographic linear content.