Hi,
On Tue, Oct 21, 2008 at 11:48:45AM +0200, Frank Schmirler wrote:
On Tue, 21 Oct 2008 09:13:15 +0200, Theunis Potgieter wrote
What is exactly involved in changing it from streaming to multi- casting, isn't it just changing the IP destination? Or does it require repacking it from mpeg2-ts to something else? Sorry if this is a stupid question.
We are not limited to TS here - any of the formats streamdev can remux to should do.
The ADB-Boxes use Multicast-TS. I have captured a transmission from my IPTV provider. So you can take a look on it:
http://www.makhutov.org/downloads/adb/
I'd say the following things are required:
- Use UDP instead of TCP for streaming (is it just switching from SOCK_STREAM
to SOCK_DGRAM or do we need to do something more, e.g. fixed/max. packet sizes?)
- Provide some way to select the channel for multicast transmission and stop
it when it's no longer needed (probably via streamdev http server menu. Or do these kinds of settop boxes support some sort of control protocol to enable/disable the stream?)
The boxes send IGMP Join / Leave Group messages, if you switch or turn on a channel.
Streamdev could listen for such messages an enable/disable the streams.
The IGMP Join Group messages are send in an interval (1 messege/minute). If an IGMP Leave Group message is recieved, or if no Join Message was received during 2 minutes then the stream sould be stopped.
The boxes also support HTML, so then can post data to a webpage, if the channel was switched. I am not sure if all boxes support this. At least the ADB boxes can do this.
The best would be implementing the stream stop/start by using IGMP as this is part of the IP-Multicast standard, so in theory all multicast clients should support it.
Regards, Artem