Wowza Community

Low Latency HLS Setup and testing

I’ve freshly installed Wowza 4.7.8 on my server and started to play with the low latency hls implementation. It appears my setup are correct based on the generated m3u8 playlist, as well as .cmfv and .cmfa files. However, the latency is still not what I was expecting for.

I understand, according to the doc, only iOS 13 can support it at the moment, however, from my testing, my iPhone (13.1.3) got a latency of about 12-13 seconds, which is roughly the same as my testings on other hls players (many available online for demo purposes). For iOS testings, I just copied and pasted the .m3u8 link into the browser and let it play from there.

Regarding my application settings, I have:

cmafSegmentDurationTarget - 3000

cmafLLChunkDurationTargetVideo - 300

cmafLLChunkDurationTargetAudio - 300

cmafLLChunkingScheme - byDuratiton

cmafLLEnableLowLatency - true

It will be great to get some hint here as what could be the problem.\

Thanks in advance,


BTW, I just upgraded my iPhone to 13.2.3, it getting the same latency as before, not really improved anything.

I can help you @Yudong Li and I’m sorry for your frustration. Safari on your iOS 13 will play back our stream, but it will not be the low latency stream.

With the new LL-HLS support from Wowza, it still means you will need to do some work on your end as far as building an iOS app accessing the native player. LL-HLS is still so very new to the industry and this isn’t a straight out of the box workflow and you won’t be able to play it back on the the native player on your iPhone 13.2.3 without a custom app.

You’ll need to build a playback app and also get permission from Apple for that app to allow for LL-HLS playback. There is a beta handshake that is required and you can only get access to that through Apple Developer program.

Hope that helps…

Hi Rose,

Thanks very much for your detailed reply. Apart from iOS devices, are you aware of any other players on browsers of PC/laptop are currently actively working towards a solution so that this won’t just be restricted in mobile device?



Yes, one moment and I will provide more info…

So, there is no LL-HLS player available yet, but Theo Player and JW Player are working on it as well as Akamai. Several companies in the industry are working hard to support it as soon as possible. When there is one ready, I will be sure to post about it in the forums.

I try test CMFA in player Akamai 7 seconds. What players and configure in wowza for 3sub seconds for delay in browser desktop?


I have developed an app with the LLHLS feature enabled.

And I have created the stream according to this:

But Im still seeing 30 seconds latency.

How can I be sure I have set up my LLHLS stream correctly on Wowza?


Thanks Rose

I got a good bit further with my low latency stream and have successfully got it working (in XCode anyway).

I am now trying to encrypt the stream and have a couple of questions.

Please see this question for a detailed description:

Thanks again!

hey Rose. i am implementing LL HLS but still latency is not improved. i am experiencing a strange thing. When i restart wowza and run, latency is around 10 seconds. but it keeps on increasing and then even refreshing page doesnt help and latency goes back to 30-40 seconds. tested different players like Jwplayer and theoplayer. attaching the application.xml file for you to look into. i have enabledApplication.xml.txt only