Icecast Streaming Media Server

[luca066]

Hi,

I'd like to know if it is possible to increase the buffer on a server for a specific mount point or for all the mountpoints.
I use Icecast to serve some streams but the encoder sometimes has got a small interruptions sending the stream (probably the sender have a problem on his internet connection).

So, is there a way to have icecast to buffer more data of the input stream so the clients will not have problem with the small interruptions from the encoder?
Clients use a flash player and they can't increase the bufer on the player side.

Thanks in advance for the answers.

Luca

[karlH]

I suspect you want to increase the <burst-size> for the mount or globally, default is 64k so may not be a lot of tolerance in such cases.

karl.

[luca066]

Hi Karl,

which value do you suggest for a 30 seconds of buffer? The stream is an aacplus at 64kbps.

thanks

Luca

[karlH]

well 64kbps is 8kbytes/s and you want 30 seconds so 240k should be in the ballpark. The default queue size is 512k so just make sure you have not set it lower than say 300k

karl.

[luca066]

Hi Karl,

your settings work great if I use a media player like winamp.
The thing really strange for me is that it doesn't work if I use a Wowza server.
We use Wowza server to restream icecast aacplus stream.
Wowza gets the stream from the mountpoints exactly like a mediaplayer, but the burst size seems not to work with this scenario.

I've done this test.
I've created 2 mountpoints: one with 512k of burst size and the second with only 128k.
Both get the stream from the same encoder.
If I listen with winamp I hear that the first one is delayed respect the second stream (and this is perfect).
So I've activated two streams on a wowza server and they restream the two icecast mountpoints.
If I listen to the wowza streams with a flash player (JWplayer) I hear the streams playing in the same timeline, and I don't understand how this could be possible.

Have you got any idea?

Luca

[karlH]

not really no, wowza may have some variable prebuffer on relaying which may affect the playback timing. It's really the sort of thing you should ask their support about.

karl.

[luca066]

Hi Karl,

I've done some tests to find a way to solve my problem.
One test was this: I've defined a mount point that receive the stream from the encoder with a burst-size set at 256kbps (/mount1).
Then on the same server I've defined a relay that gets the /mount1 to another mount point named /mount2
/mount2 has got another burst size set at 256kbps.

So, I was expecting that listening to mount2 there was a delay instaed of mount1, but I've found that they are perfectly on sync.
Probably, I've understood that this can be right: relays have to work in sync with the original mount point .. is it right?

So, is there a way to have a delay on mount2?

thanks

Luca

[karlH]

relaying is not affected by rate limiting, playback is because it goes to a soundcard. If you want a delay then you need something that slows the data rate to realtime playback speed even if it doesn't actually playback. picking up a stream, feeding through a non-encoding source client would be an example of that.

karl.