Low Latency Streaming: Threshold for catchup mechanism

[dsilhavy]

As described here Dash-Industry-Forum/dash.js#3300 and here Dash-Industry-Forum/dash.js#3316

Right now it is possible to define a target delay and playback rate catchup parameters in the ServiceDescription element of the MPD. However, if the user seeks within the DVR window it might be reasonable to ignore the increase in live delay and continue playing with a playback rate of 1 at the desired time.

We addressed this issue by adding a new settings parameter to dash.js which can be used as a threshold. For instance, if this parameter is set to 8, the catchup mechanism is only applied if currentLiveLatency < 8.

Would this be something worth adding to the ServiceDescription element as well?

[dsilhavy]

Moved this to the Live repo, will close this here