stream file source to live application stutters

Wowza Streaming Engine
1

I need to pull in a vod from a server and send it out through a live application. This works fine except when I use a player without a lot of buffering, in which case the stream begins to stutter badly. Here is how it can be reproduced with a default installation of Wowza 4.5.0 (build 18676):

  1. create a new “stream file” for this URI: rtmp:///vod/mp4:sample.mp4

  2. connect to the stream with the default live application with MediaCaster type set to liverepeater

  3. view the stream with ffplay with “nobuffer”: ffplay -fflags nobuffer -i rtmp:///live/sample.stream

You could also see the stuttering problem with a flash client with no buffering.

  • I can connect ffplay to the vod application directly with no stuttering: ffplay -fflags nobuffer -i rtmp:///vod/mp4:sample.mp4

  • I can stream the same file directly to the live application with ffmpeg and view the live stream with no stuttering: ffplay -fflags nobuffer -i rtmp:///live/sample

So for some reason when Wowza pulls this stream from vod and live streams it, it causes this stuttering problem. Is there a setting I can adjust to make it not do this?

2

I believe this is an important problem to address because if you then try to transcode this stream, your transcoded stream will exhibit the stuttering problem - with or without buffering in the client.

So to summarize:

  • all transcoded streams coming from streams pulled from vod will stutter

  • all streams pulled from vod and played with a client that has little or no buffering will stutter

3

Hi,

I’ve not found buffering myself when trying this - using the sample.mp4 as source in the stream file and then playing the “live” stream using VLC. Are you finding buffering in all circumstances or just with ffplay?

Also, you may want to look at the Stream Publisher for publishing files as a pseudo live streams. Or similarly use Stream class to publish static content as a live stream.

Regards,

Paul