All times are UTC+01:00




Post new topic  Reply to topic  [ 8 posts ] 
Author Message
PostPosted: Wed May 10, 2017 11:15 pm 
User avatar

Joined: Wed Aug 14, 2013 11:13 pm
Posts: 10
Location: Kielce/Poland
Hello! At first I apologize for the grammar, I write a translator :(
It needs information and help how to run the memo in the synchronization topic of transmitters.
1) Does the shoutcast stream have to be "powered" by a pre-processing signal from some external plugin?
2) Should the shoutcast server work on a local network, or can it work on the web as it does for synchronization?
3) why when "normal output" switches on the styreaming disappear the option of choosing what power to be "normal output"?
4) How is it solved at the station with this link, can you ask for details?
https://www.youtube.com/watch?v=PH1mUfvo7T8

I'm trying to set it offline but I do not really want to work. Shoutcast is located, both computers are downloading streams from them, but they do not play equally. Please help!


Top
   
PostPosted: Fri May 12, 2017 2:33 am 
Site Admin
User avatar

Joined: Mon Mar 17, 2008 1:40 am
Posts: 11185
1. Ideally (assuming a lossy codec) you should always do as much as possible of the processing before streaming. This does not affect synchronization though.
2. In the station of this video, it was actually running through all kinds of free WiFi connections... and as you can hear it still worked! No no local network needed.
3. What do you mean??

4. This station was actually using Winamp to receive the streaem with Stereo Tool running as a plugin, and Stereo Tool was doing the synchronization. You can also let Stereo Tool receive the stream.

The most important part is that Stereo Tool must receive the stream when it comes in, so you can't use a separate program or box to receive it. Stereo Tool needs to know when the packets of audio come in to be able to synchronize. Once that's arranged, either by using the VLC support in Stereo Tool or by running Stereo Tool in another player, just make sure to set all the buffer sizes exactly the same, and enably 'FM Transmitter synchronization". That's it.


Top
   
PostPosted: Fri May 12, 2017 8:58 am 
User avatar

Joined: Wed Aug 14, 2013 11:13 pm
Posts: 10
Location: Kielce/Poland
Hmm ... ok, i mean it's that.
1) feed stream to stereo tool
2) On each transmitter the buffers set the same
3) stream can receive via the VLC plug-in stereo tool, without the winamp
4) I enable synchronization, and at this point, when the buffers on the stereo tool are the same, I should compensate for the shifts between the transmitters.

I do it at my own and ... it does not level up, and the audio every moment you stretch and slow down but at the right moment is not equal. So how to set individual parameters in the sync section?


Top
   
PostPosted: Mon May 15, 2017 10:03 am 
Site Admin
User avatar

Joined: Mon Mar 17, 2008 1:40 am
Posts: 11185
Well it takes time before it's in sync. You have to set a large buffer size (typically around 10 seconds at least for ShoutCast streams, as that's what the ShoutCast server usually expects!!!), once the buffer filling for all the players is in the center they should be in sync. Normally you shouldn't need to do any further compensation (if the CPU speed varies a lot between machines, or if there is some constantly present latency on some of the connections, then yo do).


Top
   
PostPosted: Mon May 15, 2017 5:35 pm 
User avatar

Joined: Wed Aug 14, 2013 11:13 pm
Posts: 10
Location: Kielce/Poland
I do everything the way you write, both computers have the same settings. However, they do not play evenly. The difference between them is hardware, one is the second desktop. They do not play evenly, there is always a difference. Screen from stationary...

Image

And it's from a laptop

Image


Top
   
PostPosted: Tue May 16, 2017 2:29 am 
Site Admin
User avatar

Joined: Mon Mar 17, 2008 1:40 am
Posts: 11185
they are different sound cards. Those could have different delays. Are you using the same interface type? Also, are the processing settings the same and are the CPU's the same speed?

If there's a constant offset, use the slider on the right to compensate. With equal settings and hardware and both players listening to the same stream the latency should be identical.... but changes in OS, sound card protocol, processing settings (which may affect latency) and CPU load can affect the result. The station of which you saw the video was using 13 identical pc's.


Top
   
PostPosted: Wed May 17, 2017 3:11 pm 
User avatar

Joined: Wed Aug 14, 2013 11:13 pm
Posts: 10
Location: Kielce/Poland
Thank you for the information. I'll check it on the same PC. It still needs one more important information, how do I know how long a buffer to give? In the case of Shoutcast you talk about 10 seconds. And what if I stream directly to the Deva codec? How to measure, verify how much is needed for synchronization to work?


Top
   
PostPosted: Wed May 24, 2017 1:29 pm 
Site Admin
User avatar

Joined: Mon Mar 17, 2008 1:40 am
Posts: 11185
It will work on an setting, but if you select a value that places the buffer filling display close to the center immediately after starting playback it will get synchronized a lot faster.

Basically, if synchronization is off (buffer is not in the center), it will slightly speed up or slow down playback until it's there. So the closer it is on the start the better.


Top
   
Display posts from previous:  Sort by  
Post new topic  Reply to topic  [ 8 posts ] 

All times are UTC+01:00


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Limited