Audio descriptions for visually-impaired customers.

An Audio Description (AD) file allows visually-impaired customers to follow the film with audio that describes the plot and what is being displayed visually on the screen. A new role for a data file on the full source has been added for Audio Description. The AD file is an optional data file containing an alternative audio track. Audio Description files must be in stereo and pre-mixed format.

The AD file can be delivered as a role for the full asset using <data_file role="audio.visually_impaired">.

When delivering an AD file, you must specify the language using the <locale> tag in the <data_file> block. For example, when delivering an AD file in English, use <locale name="en-US"/>.