Wowza Community

smooth streaming: is system-bitrate required attribute

This thread https://www.wowza.com/docs/how-to-set-up-video-on-demand-streaming#ABR mentions that

the system-bitrate is calculated automatically.

Since it is calculated automatically I don’t want to specify it. I tried removing the

attribute but the streams do not play without the system-bitrate being present.

Is this a required attribute?

The thread also mentioned setting

smoothStreamingUseSMILBitrates

true

Boolean

in Application.xml HTTPStreams/Properties. This section does not exist.

I tried adding it and setting the value to false. This had no effect

I still had to have something for system-bitrate value.

I want to dynamically generate a .smil file and don’t want to do calculations to specify the system-bitrate value.

I think Silverlight calculates actual bitrate of the streams. So you should be able use any value for system-bitrate, and do not include that Property in that case.

Richard

meprospero,

In my previous testing with WMS 3.0.5 I also noticed the smoothStreamingUseSMILBitrates had no effect when added to either HTTPStream(er/s) element in Application.xml. However in my case, changing the system-bitrate in the smil to invalid values, such as “1, 2, and 3” etc… cause different behavior than with accurate bitrates. But, I think I had faulty media in my tests.

I will investigate and get back to you when I have a useful suggestion.

Could you PM me with a download link to your media with the overlays? It would help with testing. If not, don’t worry about it.

Thanks.

I think Silverlight calculates actual bitrate of the streams. So you should be able use any value for system-bitrate, and do not include that Property in that case.

Richard

From article: https://www.wowza.com/docs/how-to-set-up-video-on-demand-streaming#ABR

“Note: By default Silverlight Smooth Streaming will calculate video and audio bitrates for the manifest data on-the-fly by inspecting the file. If you want to instruct Wowza Server to use the bitrates in the SMIL file, add the following property to the HTTPStreams/Properties container in [install-dir]/conf/[application]/Application.xml (be sure to get the correct container - there are several in Application.xml). When running in this mode, Wowza will assume the video and audio system-bitrate values are for the video and audio data only:”

This setting has no effect. It appears the system-bitrate is always used. I have found the easiest way to view the switching is to burn a graphics overlay

with the bit rate of the video.

the src filenames show what bit rate the files are

On a high speed connection we see 500 followed by 1500 ending with the playback of the 20000