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Testing Wowza on LAN - is a 10-20 second delay typical?

Hi there,

I’m doing some development tests for a client and we’re interested in using Wowza for a live streaming application.

I have deployed Wowza to a local server. This setup is all running on a LAN so there shouldn’t be any network latency issues.

I’m running Flash Media Live Encoder on a Macbook Pro laptop (i5 processors, 4GB RAM). I’ve set my encoding options for H264 (as we’re streaming to iOS devices), bitrate is very low at 200kbps for video and 56 kbps for audio, resolution 320x240/15fps. Audio is MP3 mono 44khz. So…everything is quite low (IMO).

When testing a live stream to both iPad and iPhone, the latency is around 10-20 seconds. When the above settings were higher they went way up to over 30 seconds.

As per this guide (https://www.wowza.com/docs/how-to-set-up-low-latency-applications-in-wowza-streaming-engine-for-rtmp-streaming), I also included the flushInterval property in the Application.xml file:

flushInterval

25

Integer

My question is…is a delay of 10-20 seconds considered ‘normal’? What would be an ideal normal range for latency in terms of live streaming? I’m curious to know what others are experiencing so that we have an optimal setup.

Thanks,

Leonard

This is considered normal for HTTP Live Streaming. The video is segmented into chunks. You might be able to reduce this a little by reducing the chunk size in wowza (if possible).

With live streaming you should be able to obtain latencies below 1 second. For instance try using VLC to view the stream. You should have a very low latency. With my application I send iOS -> RTP -> Wowza/EC2 -> RTP -> VLC with round trip times around 300 to 500ms. The same could be achieved on iOS if you use RTP to stream into the phone.

Refer to this article for Sanjose settings:

https://www.wowza.com/docs/how-to-configure-adobe-hds-packetization-sanjosestreaming)

https://www.wowza.com/docs/how-to-control-access-to-adobe-hds-streaming-sanjosestreaming

Richard

Right, sorry. I grabbed the wrong one. This is correct:

https://www.wowza.com/docs/how-to-configure-adobe-hds-packetization-sanjosestreaming)

Richard

Glad you got it working. There’s an inherent delay in any of the HTTP delivery methods because of the packetizing process. With RTMP/RTSP, latency can usually be measured in frames, rather than seconds since the server is simply redistributing them. You add a little bit more if you’re using an edge/origin setup, but it’s often still sub-second.

-Ian

Hi,

I am streaming with SanJose/HTTP using Strobe. I have put into place on the Application.xml properties for LiveStreamingPacketizer:

cupertinoChunkDurationTarget

8000

Integer

cupertinoMaxChunkCount

2

Integer

cupertinoPlaylistChunkCount

2

Integer

cupertinoRepeaterChunkCount

2

Integer

Before & After of about 50-60 seconds behind real time. I guess these values are for Cupertino, not SJ. If so, anything to help reduce on SanJose/HTTP side ?

Thanks.

Edit: I am using Keyframes in FMLE of 2.

I have made a change by thinking on my own, to change ‘cupertino’ to ‘sanjose’.

sanjoseChunkDurationTarget

8000

Integer

sanjoseMaxChunkCount

2

Integer

sanjosePlaylistChunkCount

2

Integer

sanjoseRepeaterChunkCount

2

Integer

I have put these in LiveStreamPacketizer.xml under sanjose & repeater for both Or+Ed. to be safe.

I have gotten the delay from Live down to 25 seconds or so. If any other tips for myself + others who might just be browsing this thread, would be appreciated.

Thanks.

That seems to refer to as something about Access Control, not settings to lower delay from Live to actual stream viewed.

But appreciate it no less.

Thanks.

Refer to this article for Sanjose settings:

https://www.wowza.com/docs/how-to-control-access-to-adobe-hds-streaming-sanjosestreaming

Richard

Hi Leonard

I think this is what you need here,

https://www.wowza.com/docs/how-to-configure-apple-hls-packetization-cupertinostreaming)

Note that the key frames in your encoder should be set at about 1 second to get the lowest latency due to how HLS works

Jason

Thanks guys. With the settings, I got the HTTP streaming delay down to 7 seconds. When testing with RTSP, the delay is almost negligible. Nice.

Thanks guys. With the settings, I got the HTTP streaming delay down to 7 seconds. When testing with RTSP, the delay is almost negligible. Nice.

Hi,

can you share what you changed/added exactly in some files ?

I’m interested to get the same result as you.

Thanks

Nicolas

Able to run wowza live streaming on my local,but not able to see the live streaming on other system in LAN