Low latency recovery

Wowza Streaming Engine
1

Hi,

I’m are using Wowza for an interactive application (in that clients have the option to interact with the live stream) so I need to have as little latency as possible.

I’m streaming rtsp from ffmpeg to a Wowza live application (with Low-latency option ticked) to jwplayer (with bufferlength=0.1).

I need to ensure that all clients always see the same latency from the live video but what I’m seeing is that if a client’s bandwidth reduces for a short time the latency for this client increases and doesn’t recover.

Other clients are unaffected and if the client stops and starts the stream then this latency goes away.

To test this I’m using clients on two different PCs and using SoftPerfect Connection Emulator to simulate a lower bandwidth connection on client.

Both clients start out with negligible latency but after reducing the bandwidth on one of the clients for a short time (20-30 seconds) its latency increases to about 2.5 seconds and stays there.

I’ve tried changing the SocketConfiguration buffer settings in VHost.xml to 32000 and then to 16000 but to no avail.

Any suggestions as to how I can solve this ?

I have a related issue with latency recovery on the uplink (when bandwidth from ffmpeg to Wowza reduces) but I’m thinking this could be due to ffmpeg and not Wowza but any suggestions on this issue would also be welcome.

Regards

Colm A

2

Hi,

I don’t think the player will play the stream faster than real time (to catch up) so any latency issues will remain until the client disconnects and reconnects.

I would say this behaviour is by design and so it’s possible that you will not be able to change it, however it may be worth asking on the JW player forum.

Regards,

Jason