In Wowza Streaming Engine™ media server software version 4.7.8 and later, you can control whether EXT-X-PROGRAM-DATE-TIME tags are added to chunklists in CMAF HLS live streams. By default, the tags are not added in CMAF HLS streams. The EXT-X-PROGRAM-DATE-TIME tag associates an absolute date and time with the first sample of a chunk (or segment). This date and time can be used as a basis for seeking, for display, or for other purposes, such as for enabling a client to compute latency to the encoder or for synchronizing chunklist refresh times with an encoder.
Note: When enabled for an edge application in a CMAF live stream repeater application, the EXT-X-PROGRAM-DATE-TIME tag represents the time the edge server's packetizer received the media (or data) sent over the repeater connection.
Enable program date and time tags in CMAF HLS streams
By default, Wowza Streaming Engine doesn't add EXT-X-PROGRAM-DATE-TIME tags automatically for CMAF HLS live streams. To enable them, you need to use the cupertinoEnableProgramDateTime property in the HTTPStreamer element of the Application.xml file.
- Navigate to [install-dir]/conf/live or [install-dir]/conf/[custom live application] and open the Application.xml file in a text editor.
- In the HTTPStreamer element, add the cupertinoEnableProgramDateTime property and set it to true. The XML looks like this:
<HTTPStreamer> <Properties> <Property> <Name>cupertinoEnableProgramDateTime</Name> <Value>true</Value> <Type>Boolean</Type> </Property> </Properties> </HTTPStreamer>
- Save your changes and restart Wowza Streaming Engine.