PasTim wrote: 
> flac is all working very well indeed - thanks again for all your work. 
> 
> 
> I notice that when using firefox or vlc 3 they don't seem to run as many
> minutes behind as this plugin does.  It doesn't really matter, but I
> just wondered why.

When the Flac streams restarted, I did some testing and I heard this
dfiference one evening during a Prom concert (see edit on my post of
12-Jul-17) and thought it was odd as I had checked this before and then
there was little or no difference.  

So I have looked into this as I had assumed a coding error or something
had changed.

A bit of background. For live DASH the audio is divided into chunks.
Each chunk has to be fetched individually using a http/GET and each
chunk has an URL with a unique timecode.  In the case of the Flac
streams the timecode multiplied by 3.84 gives epochtime.

So I did a side by side comparison of the URLs for the segments being
fetched by Firefox player and my plugin and the timecode for the
segments being fetched were very close. So in this case I was not
getting  the minutes delay.  

End result - I need to do more test to see if this "delay" is consistent
or it varies (e.g. Is Prom stream DASH header different in some way) . 
If it varies - determine the reason.


Technical Info.

To minimise rebuffering, the plugin tries to pre-fetch segments.
Pre-fetching means fetching chunks that are not realtime but a few
segments older. Currently plugin is setup to prefetch 2 segment which
would result in live stream being about 7.6 secs for Flac or 13 secs for
AAC behind realtime.  LMS players have internal buffers and for live
streams the player will nto start playing until the internal bufer has
reached a threshold (i.e. Plugin setting Buffer Fullness Threshold).
With Flac the max threshold is usually reached in 2 segments (I think)
but this shouldn't be causing the delay.

Last year one of BBC technical posted in the forum that my plugin tries
to fetch segments too soon (i.e. plugin was trying to fetch segment that
weren't yet read) and BBC weren't happy as it created lots of log
messages on their servers. So I included a "guard" of 2 segments.

This means at worst plugin should be about 4-6 segment behind firefox
which for flac is 12-20 secs.


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