[Mono-dev] Streaming with Moonlight/Silverlight vs Flash

[Rolf Bjarne Kvinge]

Hi Federico,

> I am about to choose the technology that will be used during the next
> two years to build the ESOF2010 web site (if you're curious about ESOF
> just check this year website, http://www.esof2008.org/). The project
> for 2010 includes a lot of streaming using preferably open protocols
> and open source software (mandatory on the servers, the client code
> should work at least on Windows and Linux and may use proprietary
> plugins). The tools to create the streams should be free software.
> 
> We choosed to use feng as the streaming server because it supports
> RTP/RTSP and RTMP (now mostly free) with fallback on HTTP encapsulation
> and a lot of different non-proprietary codecs.
> 

The streaming Moonlight/Silverlight support is HTTP streaming
(http://msdn.microsoft.com/en-us/library/cc251059.aspx). This is basically a
protocol using HTTP to send commands (play, pause, stop, seek, etc) to the
streaming server. I don't know much about other protocols, so I can't say
how it compares to RTP/RTSP (or any other protocol for that matter).

The supported codecs are most of the Windows Media codes + mp3
(http://msdn.microsoft.com/en-us/library/bb980063(VS.95).aspx) From what
I've read about feng it does not support any of the Windows Media codecs.

> Looking at MS website for Silverlight specifications it seems to me
> that streaming using the standard protocols cited above is not
> supported and that only MS codecs (that we don't like to use) can be
> used. 

Correct.

> We also investigated the possibility of writing a a managed RTP
> implementation but it seems that UDP is not supported in Silverlight.
> And even if we manage to have a working implementation of RTP it is not
> clear how you can decode the data and send it to the multimedia part of
> the framework.

You can't.

> 
> So it seems that while we would much better like to work with
> Mono/Moonlight and keep compatibility with Silverlight in the end will
> be forced to use Adobe Flash (RTMP + one of the non-free codecs: at
> least there are open source tools to do the authoring and the encoding
> conversions).

Ffmpeg can encode to Windows Media.

> 
> I am writing to this list because I _hope_ we missed something and that
> Silverlight/Moonlight can be used to play streams using open protocols
> and codecs.

If you can't/won't use MS codecs (Windows Media), you can't use Silverlight
(support for other codecs have been requested by normal users on MS forums,
no promise has been given by MS though.)) 

However since Moonlight is open sourced it is possible to add support for
other codecs/protocols, and patches to implement this are very welcome :)

Rolf

> 
> Thank you for your time,
> federico
> 
> --
> signify error: can't use imaginary (1+0.191071i) weight!
> 
> No virus found in this incoming message.
> Checked by AVG.
> Version: 8.0.136 / Virus Database: 270.4.5/1537 - Release Date:
> 06/07/2008 5:26