Wowza Community

How can i get simultaneous playback on multiple devices?

Is it possible to play the same live stream on multiple devices at the same timecode of live stream ? For example think that in the live stream there is a clock, when playing this live stream on multiple devices you see the same time?

Hello,

If you are using RTMP or RTSP streaming protocols on your devices, you should be able to see the same stream at about the same time.

However, when talking about HTTP based streaming protocols, because these streaming protocols are based on media chunks, there can be a delay between different devices, depending on the time it takes to download a specific chunk and which chunk is being downloaded and played back by a specific client at a given time.

This is more of a streaming protocol restriction.

Can you describe in which scenario the simultaneous playback in different devices would be used?

Zoran

There really is not a way to ensure that a live stream will be playing at the same point for each client, even among identical clients because of network factors, and between different clients because of different packetizing. The HTTP streaming types have more latency than RTMP and RTSP because of they way they are packetized into chunks.

Richard

Hi,

Are you comparing the multicast stream with VLC player against the RTMP stream from Wowza, or just 2 RTMP streams from Wowza?

Is the multicast stream being ingested by Wowza or is the multicast stream being pushed out by Wowza?

Jason

In RTP multicast streaming when playing the rtp stream via vlc on multiple devices i can watch the same scene. But when play rtmp i cant see the same scene. one device is showing 5 seconds ago scene, one device 3 seconds ago scene… so i want to play the same scenes the same time via rtmp.

Hello,

If you are using RTMP or RTSP streaming protocols on your devices, you should be able to see the same stream at about the same time.

However, when talking about HTTP based streaming protocols, because these streaming protocols are based on media chunks, there can be a delay between different devices, depending on the time it takes to download a specific chunk and which chunk is being downloaded and played back by a specific client at a given time.

This is more of a streaming protocol restriction.

Can you describe in which scenario the simultaneous playback in different devices would be used?

Zoran

I just want this scenerio;

I will setup Wowza To local server. For example the ip adress of server is 192.168.1.2

Then i will write a rtsp player on android devices. I just want to learn that, is it possible to everyone who has android devices connected to that local network , can be watched the same scene at the same time?

Hi,

Are you comparing the multicast stream with VLC player against the RTMP stream from Wowza, or just 2 RTMP streams from Wowza?

Is the multicast stream being ingested by Wowza or is the multicast stream being pushed out by Wowza?

Jason

There really is not a way to ensure that a live stream will be playing at the same point for each client, even among identical clients because of network factors, and between different clients because of different packetizing. The HTTP streaming types have more latency than RTMP and RTSP because of they way they are packetized into chunks.

Richard

Actually, there is. :slight_smile: Given that output is piped through a player that supports currentTime (with good precision) and variably playbackRate, we do echo-less playback on most devices in most browsers. There is no restriction to be on the same network or use similar hardware. We’ve demonstrated it both with a custom mp3 server (using only html audio tag or playback), as well as more advanced live systems, like the Shaka DASH player. On demand using HTTP is trivial and needs no additional support on either end.

http://motioncorporation.com/ or http://dev.mcorp.no/ for developer resources.

N