Level3 CDN issue affecting RTMP HD downloads

Jim web web at audiomisc.co.uk
Fri Sep 11 01:25:04 PDT 2015

In article
<trinity-c4f00192-8638-46f8-a340-fc2843dbe10a-1441915038484 at 3capp-mailcom-bs13>,
   tellyaddict <tellyaddict21 at gmx.co.uk> wrote:

[ snip clarifications with thanks :-) ]

> > I got about 1/3rd of real time rate. i.e. it would take about three
> > hours to fetch an entire 1 hour 1280x720 program. Are you saying that
> > is a "good speed"? Or are you saying the slooow rate I got was
> > anomalous and I should try again a few times to see if I was 'unlucky'
> > when I tested this?

> No what you are getting is not a good speed. I have just tried a 1 hour
> episode of Homes Under the Hammer in HD and got around 300fps and the
> download took about 6 minutes.

I tried again this morning (6:45am). This time hls ran very quickly!

For my hls tests I've been using a command line in a terminal so I can
ensure that I repeat the same command. On the previous occasions hlsbest
was only running at around 8 fps. This morning it was running at over 400
fps. Big increase! :-)

Once that was happening I modified my own simply ROX app for fetching lists
of items, and it duly rattled though half a dozen at over 400 fps. Really
pleased and relived.

I have no idea why it was so slow before, but may have simply been down to
bad luck and I did it when something was getting in the way, or whatever.

The hls fetches seem to throw up a complaint about packet timing which I
associate with the lip sinch being affected. However I tried a few of the
resulting files and they seem fine. The Bach Cello Sonatas were a good test
of that, but meant I then got hooked...  8-] Is it the norm for hls fetches
to start with a warning about the timings? Its similar to the messages I
can get when using ffmpeg to clean up DVB-T2 stream grabs.

> In the not too distant future, HLS will become the only option for us to
> use. The BBC are planning to get rid of the RTMP streams in the near
> future but we don't know when. The RTMP options could disappear at any
> time though.

Yes, I've been well aware of that for some time! You may have missed when I
did a webpage on 'Audio Factory' that deals with the overall developments.
I was told then that RTMP would probably stay though the Proms. But beyond
that it may well go soon. The changes this week are a step along the way
towards the eventual demise of RTMP I think.

Now relieved and pleased that hls works here OK!  :-)


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