3.2.5.2.3.1 Sending an On Playback Started Message

The structure and fields of the On Playback Started message are specified in section 2.2.5.3.1.

The On Playback Started message MUST be sent when a presentation has started playing on the server or when a presentation is started after a seek operation. This message MAY <12> be sent multiple times if the detection of playback start happens in a stream and if there are multiple streams in a presentation.