Wowza Community

When is Transcoder AddOn Needed (for live ABR streams)?

I apologize in advance if this a noob question, but I are one right now. I’m currently evaluating Wowza 4 (using a trial license) on Amazon EC2. I have the instance up and running and I’m exploring all the options on the Wowza Streaming Engine web GUI. My primary interest in Wowza involves live ABR streaming and transcoding/repackaging to multiple live ABR formats. I’ve been reading lots of quick start guides, tutorials, etc, but I need to ask the following:

I understand that I can encode a single high quality stream, push it via RTMP to Wowza and it can transcode it to several ABR streams in multiple formats using the Transcoder AddOn.

But what if I’m encoding an ABR stream (consisting of 4 or 5 variant bitrates) on my encoder and pushing those to Wowza (via RTMP)? Can Wowza repackage those to the other flavors (HLS and MSS) without using the Transcoder AddOn? Can it be done with the Transcoder AddOn? (We have a ViewCast Niagara encoder that can encode live ABR streams in Adobe FDS, Apple HLS, and Microsoft Smooth Stream flavors.)

Thank you!

The key to ABR is key frame alignment, If your encoder can produce the multi-bitrate renditions with key frames aligned then you do not need the Transcoder.

See this guide to set up Adaptive Bitrate Streaming:

How to do adaptive bitrate streaming

And you can use this guide to check if key frames are aligned from the encoder:

How to debug encoder multi-bitrate key frame alignment

Salvadore

Hi,

The first URL:

http://[wowza-ip-address]:1935/live/smil:myStream.smil/playlist.m3u8

Allows playback from a group of streams (.smil file) for ABR

The seconds URL:

http://[wowza-ip-address]:1935/live/myStream/playlist.m3u8

Allows playback from a single published stream only.

Daren

Hi,

Correct. The trial version does not include HTTP Origin functionality.

Best regards,

Daren

Thank you Salvadore.

I believe the key frames are aligned. We have done many HLS streams using that encoder (streaming through Akamai – not repackaged to other flavors) and they play well on iPads, iPhones and some Android devices (ie, Galaxy S4). I’ll check out that debugging article to check and see if they are aligned.

I’ve already read the tutorial in your first link. I have a related question:

In that tutorial, they say:

For live adaptive bitrate streaming with the SMIL file created previously, use the following URL syntax in an iOS device:

URL:

http://[wowza-ip-address]:1935/live/smil:myStream.smil/playlist.m3u8

For more information about iOS playback see How to playback on Apple iOS devices (Cupertino/Apple HLS).

But if you click on that link, they say:

Enter the following URL into the Safari web browser on the device:

URL:

http://[wowza-ip-address]:1935/live/myStream/playlist.m3u8

Why the different formats in the URLs? (The first use a SMIL file; the second one doesn’t.) (I put the URLs in code brackets to prevent truncating.)

Thank you Daren.

One more question: I’m using a trial license right now. I understand that the trial license does not provide HTTP Origin services. So I can’t publish ABR streams to Amazon CloudFront with a trial license then, correct?

Thank you so much!