Support for Preselection elements

[stschr]

Description

DASH-IF IOP for ATSC makes heavy use of Preselection elements; DVB-DASH exercises them as well.
Due to lack of appropriate APIs in Web browsers, ATSC has defined its own API towards decoders to select preselections called Media Track Selection API (see ATSC A/344:2023, clause 9.7.7)
To use dash.js in ATSC3 environment, support for reading Preselection elements by dash.js is required.

Task

Parse Preselection elements from MPD and expose information with a structure "aligned to" MediaInfo. (details t.b.d.)

[danips]

Hi @stschr , are you actually working on this feature?

[stschr]

Hi @danips ,
well, I filed this topic as outcome from the dash.js roadmap planning.
Yes, I intend to implement this; although we're yet in a planning phase.