Leadtools.Multimedia Namespace > RTSPServer Class : SetLiveLatency Method |
'Usage Dim instance As RTSPServer Dim index As Integer Dim latency As Double instance.SetLiveLatency(index, latency)
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 set using this function. The live stream latency is a double value and is measured in seconds.
If index is between 0 and SourceCount - 1 (where SourceCount is the number of folders in the list, as indicated by SourceCount), this method sets the LiveLatency settings for the source with the index equal to index.
If index is set to -1, this method sets the default LiveLatency setting for the RTSP server. All the current folders are set to this LiveLatency setting. Also, all future folders added with SetSourceFolder will use the default LiveLatency setting.
If you never set the LiveLatency setting for the RTSP server, the default value is 0.5 (for 0.5 seconds behind live).
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 Creating a LEADTOOLS Multimedia Capture Application using LEADTOOLS DVR 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.