Does ExoPlayer support multiple EventStream tags in the same DASH period?

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[REQUIRED] Question

When playing a DASH VOD stream with multiple <EventStream> tags in the same period, only the events from the first EventStream seem to be emitted. Is that a known limitation of ExoPlayer, intended behaviour or a bug?

Link to test content

The manifest looks something like this:

<Period id="123456" start="..." bitstreamSwitching="true">
    <EventStream schemeIdUri="urn:scte:scte35:2014:xml+bin" timescale="90000">
      <Event id="2">
      ...
      </Event>
    </EventStream>
    <EventStream schemeIdUri="urn:scte:scte35:2013:xml" timescale="90000">
      <Event id="2">
  ...
      </Event>
    </EventStream>
    <AdaptationSet mimeType="video/mp4" segmentAlignment="true">
...
</Period>

Edit: I send you an email with a sample stream.

[ojw28]

Heh, yes! It’s a limitation due to the current architecture, where there are a static number of renderers and each one can only play a single TrackGroup. This largely makes sense for audio and video, short of very niche use cases. The same is mostly true for text and metadata as well, however for these track types it is somewhat more likely for there to be use cases that need multiple tracks selected at once, as is the case here.

I think we’ll try and remove this limitation at some point, but it’s unlikely to happen any time soon because it will likely require a fairly non-trivial architectural change. It’s also not entirely clear what that change should be, and whatever we do it’ll likely have some significant implications for how track selection works. So, it’s something that we think it’s best to live with for now, given there is a way (albeit a hidden one) to get things working for those who need it!

[strangesource]

Thanks very much for the context, makes a lot of sense how you described it.