Creates a filter that keeps audio-description renditions out of (or, when
opted in, restricts audio to) the audio selection.
preferDescription: false (default): drop audio-description renditions
from each period when a non-description audio alternative exists, so the
main audio is chosen by default instead of the description track. If a
period has only description audio, it is kept (playback is never stranded).
preferDescription: true: keep only description renditions when the period
has any; otherwise keep all (again, never strand playback).
Creates a filter that keeps audio-description renditions out of (or, when opted in, restricts audio to) the audio selection.
preferDescription: false(default): drop audio-description renditions from each period when a non-description audio alternative exists, so the main audio is chosen by default instead of the description track. If a period has only description audio, it is kept (playback is never stranded).preferDescription: true: keep only description renditions when the period has any; otherwise keep all (again, never strand playback).Non-audio qualities are always kept.