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NEW! Settings to edit in Wowza Video and OBS for low latency

This video dives into the OBS details that could be causing higher latency than desired. It also shows some advanced properties in Wowza Video you can edit to reduce the latency especially if you use Stream Targets.

These settings are critical to edit if you want to get traditional HLS latency down as low as possible (6 to 12 seconds) from the normal 30-45 seconds.

You can also deliver the RTMP stream from OBS as WebRTC for close to real time. Justin also covers this in the video.

I noticed in the video when editing the transcoder he chose to select a 0 second buffer size but didn’t turn off the sort packet buffer (which is set by the low_latency property when using the API). Does that make much difference to the quality/latency?

Great question and I just asked docs to make sure the article matches what’s going on in the video or vice versa.

So here is the deal:
Turning off the sort packet buffer speeds the time it takes to decode and deliver video data to players. Could be 2 seconds or more so yes it affects latency if you are really trying to get it down as much as possible.

When you “enable low latency” in the UI or in the REST API, we turn off that sort packet buffer and change the buffer to 0.

You do have the option to edit those settings because sometimes too small of a buffer or turning off the sort packet buffer can result in some choppy playback if your network isn’t fast enough. etc. ( For low-latency HLS playback)

A buffer of 0 is great for RTMP input and WebRTC playback, but be cautious how low you go with HLS. Justin changes it to 0 in the video and you can, but run some tests to make sure your playback is smooth for HLS. Might be better to go with 4 seconds as a buffer in my opinion.

Summary:

Sort packet buffer: We turn it off when you select enable lower latency.

We do give you the option to turn it back on though.

Did that help @Daniel_Taylor ? I think the deselect language is confusing and will request we adjust that.

And I agree that the video is confusing for that part.

That’s great thank you. We use HLS playback so I’ll go and have play with the buffer size.

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It’s really tough with HLS playback to get it below 8 seconds but it is possible with optimal server and network conditions. Good luck!

Looks like the YouTube account for this video has been terminated. Can we view it another way? I’d definitely like to watch it. Thanks!

Oh no! Let me figure out what happened and get that fixed asap.

Thanks @Shane_Higgins for the heads up on this- it’s the entire You Tube library that’s down. :disappointed: Our marketing team is investigating what happened and I’ll let you know when it’s restored and back online.

Oh dang! Somebody forgot to pay the YouTube bill. Oh wait… :wink:

Thanks for looking into it!

Ha!
It’s back up and running @Shane_Higgins, sorry for the inconvenience!

Rose

Thanks Rose! That video was very helpful!

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