Wowza Community

Push Publishing to Limelight

Hi,

I am pushing a single bitrate, high quality RTMP stream to Limelight CDN. Limelight network transcodes/transrates this into five (5) video streams for HLS and HDS playback. When these streams are viewed, I monitored that the streams keep on buffering every minute or so, even there is sufficient bandwidth. I tried to play the original, high quality RTMP source using Wowza test player and JW player, and it played perfectly. Is it possible that the cause of this issue is the keyframe interval requirement of Limelight? Based on its documentation, the keyframe interval must be set to five (5) seconds. But I do not have any idea how to set this since the stream that I am pushing to Limelight network is composed of pre-recorded contents played as live stream. (I used Wowza streamscheduler.smil for this stream).

Apart from the above question, do I need to set in the PushPublishMap.txt the following parameters?

adaptiveStreaming

sendOriginalTimecodes

originalTimecodeThreshold

By the way, I am asking that since Limelight has this note on its documentation:

“NOTE: Ensure your Primary and Backup streams are time synched using absolute timecodes to avoid disrupting the end-viewer experience when the stream switches to the Backup Ingest.”

Additional info: I’m using Wowza Streaming Engine 4.1.2 AMI on Amazon EC2 (Singapore)

Limelight publishing points are located in Japan (primary) and Australia (secondary)

My contents has key frame interval of 2 seconds and are stored at Amazon S3.

Thanks,

Roger

Hello Roger,

The Keyframe Interval is set on the encoder. For example, if Lime Light is looking for a 5 second keyframe, and you are sending out at 30fps, you need to set the keyframe interval or the GOP to 150. This will give you the 5 seconds needed. Wowza Streaming Engine passes this keyframe through to Lime Light.

You may need to consult the User Guide for the encoder settings.

Please let us know if you need additional assistance.

Regards,

Mac

Hi Mac,

Would it be possible to push publish to another application within the same Wowza Streaming Engine?

Instead of push publishing the stream (from App1) direct to Limelight, the stream will be push published first to App2, in which the transcoder is enabled, so that I can set the required keyframe. Then I’ll push publish the stream from App2 to Limelight?

Do you think this will work?

Thanks,

Roger

Hello,

Push publishing from one Application to another on the same machine is possible but you’d probably be better off using the ModuleDuplicateStreams available in the Wowza Modules Collection and this will duplicate the incoming streams in multiple Applications.

If you have further questions, please elaborate on your Application workflow.

Best regards,

Andrew