The Apple HLS specification includes support for two bitrate attributes to be specified in Apple HLS master playlists: the BITRATE (peak bitrate) and AVERAGE-BITRATE (average bitrate). By default, Wowza Streaming Engine™ media server adds only the BITRATE attribute to Apple HLS master playlists. This article describes how to configure the cupertinoEnableAverageBandwidth property in Wowza Streaming Engine to enable the AVERAGE-BITRATE attribute in the master playlist.
- In Wowza Streaming Engine Manager, click the Applications tab and select your application in the contents panel.
- In the details page, click the Properties tab, and then click Custom in the Quick Links bar.
- In the Custom section, click Add Custom Property, specify the following settings in the Add Custom Property dialog box, and then click Add:
- Path - Select /Root/Application/HTTPStreamer.
- Name - Enter cupertinoEnableAverageBandwidth.
- Type - Select Boolean.
- Value - Enter true.
- Click Save, and then restart the application when prompted to apply the changes.
For adaptive bitrate streams, you must specify the average bitrate in your SMIL file in the <param> for each bitrate rendition:
<param name="cupertinoTag.AVERAGE-BANDWIDTH" value="[value-in-bits-per-second]" valuetype="data"/>
The average segment bitrate for each live stream rendition must be less than 110 percent of the AVERAGE-BANDWIDTH attribute.
The average segment bitrate for each VOD stream rendition must be within 10 percent of the AVERAGE-BANDWIDTH attribute.