GAMBAS BOOK 3.19.5

The MediaLink class represents the link between two MediaControl objects and is only used in the GetLink(…) method of the MediaControl class. This class cannot be created.

The MediaLink class only has these four relevant properties:

Table 23.9.5.1.1 : Properties of the MediaLink class

Figure 23.9.5.1.1: MediaPipeline with links

The MediaControls are linked in the following source code section in lines 11 and 12. Lines 25 to 46 then show how you can read and display information about the mcConvert control:

  [1] Private mpPipeline As MediaPipeline
  [2] Private mcSource As MediaControl
  [3] Private mcConvert As MediaControl
  [4] Private mcSink As MediaControl
  [5]
  [6] Public Sub CreateAndPlayPipeline()
  [7]
  [8]     Dim i As Integer
  [9]     Dim hInputs As String[]
  [10]     Dim hOutputs As String[]
  [11]
  [12]     mpPipeline = New MediaPipeline As "hPipeline"
  [13]
  [14]     mcSource = New MediaControl(mpPipeline, "uridecodebin")
  [15] '-- ["uri"] is a property of the MediaControl 'mcsource' or the Gstreamer element 'uridecodebin'.
  [16]     mcSource["uri"] = ComboBox1.Text
  [17]     mcConvert = New MediaControl(mpPipeline, "audioconvert")
  [18]     mcSink = New MediaControl(mpPipeline, "autoaudiosink")
  [19]
  [20]     mcSource.LinkLaterTo(mcConvert)
  [21]     mcConvert.LinkTo(mcSink)
  [22]
  [23]     mpPipeline.Play()
  [24]
  [25]     hInputs = mcConvert.Inputs
  [26]     For i = 0 To hInputs.Max
  [27]       Print "mcConvert-Input: "; i; hInputs[i]
  [28]     Next
  [29]     hOutputs = mcConvert.Outputs
  [30]     For i = 0 To hOutputs.Max
  [31]       Print "mcConvert-Output: "; i; hOutputs[i]
  [32]     NexthOutputs[i]
  [33]     Next
  [34]
  [35]     Print "\nMediaLink parameters around the mcConvert input:"
  [36]     Print "------------------------------------------------"
  [37]     Print "Type of mcConvert input: "; mcConvert.GetLink("sink").Name
  [38]     Print "Name of mcConvert MediaControl of other side :"; mcConvert.GetLink("sink").Peer.Name
  [39]     Print "Name of output of other side of mcConvert: "; mcConvert.GetLink("sink").Output
  [40]
  [41]
  [42]     Print "\nMediaLink parameters around the mcConvert output:"
  [43]     Print "-------------------------------------------------"
  [44]     Print "Type of mcConvert output: "; mcConvert.GetLink("src").Name
  [45]     Print "Name of mcConvert MediaControl of other side: "; mcConvert.GetLink("src").Peer.Name
  [46]     Print "Name of input of other side of mcConvert: "; mcConvert.GetLink("src").Input

This is the output in the console of the IDE:

mcConvert-Input:  0  sink
mcConvert-Output:  0  src

MediaLink parameters around the mcConvert input:
------------------------------------------------
Type of mcConvert input: sink
Name of mcConvert MediaControl of other side: uridecodebin0
Name of output of other side of mcConvert: src_0

MediaLink parameters around the mcConvert output:
-------------------------------------------------
Type of mcConvert output: src
Name of mcConvert MediaControl of other side: autoaudiosink0
Name of input of other side of mcConvert: sink