Video Streaming Server

[lang er]

Thank you for your suggestion.

Do you mean a C program reads video stream from device and transfer
data to Erlang server using local socket, then Erlang server streams
video data to client?

Our server will connect to many devices(if user watch many different
cameras installed on many different devices).By this way, C program
also need to deal with many concurrent problems. It supposed these
problems should be done in Erlang side, and  there will be little
benefit to reimplement streaming server in Erlang.

Another problem, In surveillance system, QoS( network delay
especially) is very import, I think your solution may introduce some
additional network delay.

I wonder if this is the standard way Erlang program use external SDK.
I have read some posts in this list, and got a impression that Erlang
is used in telecommunication device systems and hardware controller
programs. Don't they need interact with SDK(dynamic linked library)?


Best Regards!
James


在 06-8-12，David Hopwood<david.nospam.hopwood@REDACTED> 写道：
> lang er wrote:
> > 1. We need connect to  many different kinds of video devices, some of
> > these device vendors provide communication protocols to us, and we can
> > implement them in native Erlang code. But some vendors only provide
> > SDK(no source code), so should we use linked-in Port Drivers? And If
> > SDK use native OS thread, are there any problems?If there are, How can
> > we get out of these problems? or What is the best way to use these
> > SDKs in Erlang?
>
> I would suggest to use each vendor's SDK in a separate process running
> a C program, and communicate with these processes over local sockets.
> The C program can translate the video to a vendor-neutral protocol. This
> avoids any potential conflicts over threads or other resources within a
> process, which you might not be able to solve without source code. It
> also means that any instability in a vendor's code can be worked around;
> if its process crashes then you can restart it, and you can also restart
> it periodically to avoid potential memory leaks.
>
> I don't know whether the inability to use shared memory to communicate
> with the Erlang program would result in performance problems; probably
> not if the video streams are coming over a network to start with.
>
> --
> David Hopwood <david.nospam.hopwood@REDACTED>
>
>
>