SCTE 248 2018

Operational Practice on Multiple Audio Signaling

Cable operators, many program networks, and local broadcast affiliates routinely support up to two audio streams for programs they distribute. The first audio stream contains the main or primary audio for the program, typically in English; the second audio stream contains the audio description or a second language (typically Spanish). However, this legacy two-stream model can conflict with the desire to offer additional languages, video description service (VDS), emergency information and other audio services simultaneously. Newer equipment, including set-top boxes, and IP delivered content can support this capability; advanced audio technologies, such as object-based audio, will allow the consumer more choice of what they hear. This document provides guidance and recommendations to cable operators and program providers on distributing multiple audio streams, languages and services while supporting legacy requirements.