Adding Multi-bitrate Audio-only Rendition to iOS Streams (AppStore 64Kbps)

[charlie]

See the following article:

http://www.wowzamedia.com/forums/content.php?208

The Wowza Team

[ianbeyer]

Thanks, Charlie!

This is particularly relevant if you're a Roku channel developer. The recent 2.6 build 693 changed the minimum bitrate required by Roku for HLS streams to 250000, and it was refusing to play any HLS content coming out of Wowza.

http://forums.roku.com/viewtopic.php...=31051&start=0

[chwang]

Hi Charlie,
I have been trying to playback an audio only stream on iPhone for several days using Wirecast encoder and Wowza Media Server but no luck. Then I found this thread.

Questions:
1. Do I need to following the 1 and 2 steps? I don't need multibitrate stream. All what I want is to playback an audio only source on iPhone.

2. Does the audio bitrate have to be 64kbps or less on the encoder? Mono or stereo?

3. As my question, what settings I need to use to make it work on iPone?

4. I downloaded the latest version of Wowza Media Server in this August. Doesn't contain all the patches?

Thanks a lot!

[rrlanham]

This technique is for extracting an audio track from an audio/video stream. Will that help you? Is the purpose of your audio only stream to satisfy Apple requirements? You have been using 128kbs audio in your support thread.

Richard

[tktnopbtupeuxpastest]

Thanks, Charlie!
I just tried it and it's very usefull to have this audio stream autogenerate for the adaptative streaming with smil.

However, I just find a problem.
When I try this on one server like your exemple everything works fine. But when I use it with a repeater configuration, the edge doesn't seem to find the stream. On the edge it's becoming impossible to play any cupertino stream whereas on the origin everything works fine. I check the log and the only problem I see on the edge :

ERROR server comment - CupertinoStreamerLiveRepeaterReceiver.addVideoData[2]: java.lang.NullPointerException
ERROR server comment - CupertinoStreamerLiveRepeaterReceiver.addVideoData[2]: java.lang.NullPointerException

I made some test and I see that when I remove the autogenerate stream on the origin :

<Property>
 <Name>cupertinoCreateAudioOnlyRendition</Name>
 <Value>true</Value>
 <Type>Boolean</Type>
</Property>

The audio stream obviously doesn't work but I can play other cupertino stream like before.

This is a known problem like for the recent FlashHTTP where we can find in the README.html :

• Multi-bitrate does not work for live streaming
• Live stream repeater for Flash HTTP streaming is not working

or I get a problem and I need to made some tunning on the edge to make it work ?

[rrlanham]

Try configuring this on the edge instead of the origin. So the edge pulls a simple stream from the origin, the audio extraction is done on edge.

Richard

[tktnopbtupeuxpastest]

I try it but it doesn't work either. All normal cupertino stream work but when I try one with audio only, when the edge start the connection to the origin I get :

ERROR server comment - CupertinoStreamerLiveRepeaterReceiver.addVideoData[2]: java.lang.NullPointerException

And if I try to play it I get :

INFO server comment - HTTPStreamerMediaCasterStreamLock.lockRepeaterStre ams[cupertinostreamingpacketizer:cupertinostreamingrep eater:httprepeater]: repeaterLock: streamtest

So the audio extraction doesn't seem to work with liverepeater-edge application. I think this could be because of the "cupertinostreamingrepeater" but it's not working either with "cupertinostreamingpacketizer".


And I think that it's not a really good idea to move the audio extraction (or any other packetizer) on the edge part.
The stream need to be started for audio extraction. And for the moment, the only solution I see to do that, is to had all those stream in the StartupStream.xml. Just to connect the edge server to the origin and start the extraction.

The main problem of this solution is the high load needed because all stream will be started at startup between all edge server and the origin, just to generate an audio stream.

[rrlanham]

I did test this with liverepeater. I will try it again in awhile.

Richard

[rrlanham]

For this to work in a liverepeater configuration, you have to setup the LiveStreamPacketizer and HTTPStreamer Properties in the edge Application.xml.

Then I created created a .stream file that pointed to the origin on the edge server.

File name:

/contents/origin.stream

With contents:
rtmp://[wowza-address]:1935/origin/myStream

Then I started in edge server StreamManager on the edge application with MediaCaster type "liverepeater"

To test, I played this url in the IPhone:

[codel]http://[wowza-address]:1935/edge/origin.stream/playlist.m3u8?wowzaaudioonly[/code]

It is not necessary to configure the properties in the origin's Application.xml

Richard

[chwang]

What URL should I use if I only want to playback the audio only stream on iPhone? Suppose the URL for the stream with both video and audio is http://[server-ip]:1935/live/myStream/playlist.m3u8?

Thanks a lot!