Leadtools.Multimedia Namespace > RTSPServer Class : GetLiveLatency Method |
'Usage Dim instance As RTSPServer Dim index As Integer Dim value As Double value = instance.GetLiveLatency(index)
The RTSP server treats growing DVR buffers as a live stream. When a RTSP client connects and requests playing a growing DVR buffer, the RTSP server starts playing from the current position in this live stream. For performance purposes, it starts a little bit behind the live stream. The amount by which it is behind the is called "live stream latency" and its amount is retrieved using this function. The live stream latency is a double value and is measured in seconds.
This function allows you to get the live stream latency for a source (if index is between 0 and SourceCount - 1) or for the server (if index is -1).
The default live stream latency is 0.5 (meaning the live stream is 0.5 seconds behind the live stream).
A DVR buffer is considered to be growing if it is still being written to by the DVR engine when a RTSP client requests it.
See the Introduction to the LEADTOOLS MPEG2 Transport Module topic for more information on DVR files.
If the source DVR buffer is using a compression compatible to the RTSP server, the streaming will start from the first key frame found before the "Live Stream Position" - "LiveLatency". This is done for performance purposes, because the streaming must start with a key frame.