Question about server-side playlist playback

Wowza Developer Dojo
1

Hi guys,

I would use the server-side playlist to broadcast a fake live stream. But I noticed a behavior that I did not understand. I’ll explain.

Lets take a look at my playlist :

<playlist name="playlist_01" playOnStream="stream_01" repeat="false" scheduled="2014-03-27 16:00:00">
	<video src="mp4:video_01.mp4" start="0" length="100"/>
	<video src="mp4:video_02.mp4" start="0" length="100"/>
	<video src="mp4:video_03.mp4" start="0" length="100"/>
	<video src="mp4:video_04.mp4" start="0" length="100"/>
	<video src="mp4:video_05.mp4" start="0" length="100"/>	
</playlist>

My question is :

Normally, or that what I thought, when I play “stream_01” at 4:04:00 p.m. I must get the 40th second of “video_03” :

4:00:00 p.m. + (video_01: 0:01:40) + (video_02: 0:01:40) + (video_03: 0:00:40)

but it plays “video_01”.

So, could you please tell me if this is a bug on wowza or this is the normal behavior ? and what should I do so that I get “video_03” at 4:04:00 p.m.

Thanks,

2

Hi there, you could try setting the length of each video to -1 for the length parameter. That is if you are trying to play the entire video. Any positive value will play the source for that number of seconds.

Salvadore

3

Okay, so you want video_3 to start at the 40 second mark of the video at exactly 4:04.00?

It looks like the first two videos are only 3 minutes and 20 seconds long combined with 100 as the length parameter, so that should put video_3 starting from the beginning at 4:03.20 pm.

If you had move data in video_1 and _ 2 you could increase the length to fill out the time to 4:04.00 pm. Or create a second playlist that starts at 4:04.00 that plays video_3, and have a 40 seconds of “dead air”.

If you want video_3 to start playing at the 40 second mark, you will need to change the start time from 0 to 40.

If I am not understanding your question correctly, I apologize.

Salvadore

4

What guide are you following for this? Also, what version of Wowza are you running?

Here is a guide that will achieve “fake live” with static content:

How to do basic server-side publishing with Stream class streams

Salvadore

5

Are all the clients local? Or could there be any network factors to consider?

You can start Wowza in stand-alone mode, [instal-dir]/bin/startup.bat(startup.sh on Mac) and see the switching in the console.

Did you configure just the ServerListener, or just the Module, or perhaps both?

Salvadore

6

I am glad you got this working, thanks for the update.

Salvadore

7

Hi Salvadore and thank you for your interest in my problem.

I explain again my problem with two examples :

  • I shedule my playlist to start at 10:00:00

  • My playlist contains 5 videos :

	- video_01 : video duration : 05:22, start playing from : 0, playing duration : 120 seconds ( 2mn)
	- video_02 : video duration : 03:55, start playing from : 0, playing duration : 120 seconds ( 2mn)
	- video_03 : video duration : 11:40, start playing from : 0, playing duration : 120 seconds ( 2mn)
	- video_04 : video duration : 07:07, start playing from : 0, playing duration : 120 seconds ( 2mn)
	- video_05 : video duration : 06:13, start playing from : 0, playing duration : 120 seconds ( 2mn)

I used 120 s instead of 100s to simplify calculation to better understand the situation :wink:

1 - working example ( I got what I want ) :

  • It’s 09:58:00, I open my player and connect to rtmp://localhost/playlist to play my stream ( stream name : stream_01 )

of course I got NetConnection.Connect.Success, and the player is waiting to playlist that will start in 2 mn ( 10:00:00 - 09:58:00 = 00:02:00 ).

At 10:00:00, the player starts ( automatically ) playing my first video ( video_01 ) from 0.

At 10:05:00, I open another player ( like the first one ), which starts playing video_03 from the second 60 ( 00:01:00 of 00:11:40 )

=> 10:00:00 + ( video_01 : 00:02:00 of 00:05:22 ) + ( video_02 : 00:02:00 of 00:03:55 ) + ( video_03 : 00:01:00 of 00:11:40 )
=> 10:00:00 + 00:02:00 + 00:02:00 + 00:01:00 = 10:05:00

I got what I want, all people watching the stream will have the same moment of the (fake) live whatever their connection times.

2 - not working example :

  • At 10:05:00, I open, for the first time, my player and connect to rtmp://localhost/playlist to play my stream stream_01, but instead it starts the second 60 of the video_03, it starts playing the first video ( video_01 ) from 0 !!

My conclusion : Either there is a bug in wowza (I think this is the most propable) or wowza server-side playlist can not be a fake live !

I hope it’s clearer now, thank you for your help.

8

Wowza version : 3.5.0

I used this guide : https://www.wowza.com/docs/how-to-schedule-streaming-with-wowza-streaming-engine-streampublisher.

9

Hi all,

Thank you Salvadore for all your answers.

I think I found a solution : when I send “loadSchedule” command to wowza server to update the playlist, I’ll initiate the stream on server by playing it after receiving the validation from server that playlist was succesfully updated.