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Waveform.PeaksBufferGet method |
  
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Waveform.PeaksBufferGet method |
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Remarks
Fills two buffers with min and max waveform peaks for the given range. The size of each buffer can be obtained with a previous call to the Waveform.PeaksBufferLengthGet method.
Before calling this method it's mandatory performing a previous sound's analysis through a call to the Waveform.AnalyzeFullSound method.
For further details about using the embedded Waveform refer to the Waveform class section.
For further details about generating a waveform bitmap of the loaded sound, before starting its playback, refer to the How to obtain the sound's waveform tutorial.
Syntax
[Visual Basic] Public Function PeaksBufferGet ( nPlayerIndex as Int16, nChannel as Int16, nStartPos as Int32, nEndPos as Int32, bValueInPerc as Boolean, pBufferMin() as Int16, pBufferMax() as Int16, nBufferLength as Int32 ) as enumErrorCodes |
[C#] public enumErrorCodes PeaksBufferGet ( Int16 nPlayerIndex, Int16 nChannel, Int32 nStartPos, Int32 nEndPos, bool bValueInPerc, Int16[] pBufferMin, Int16[] pBufferMax, Int32 nBufferLength ); |
[C++] public: enumErrorCodes PeaksBufferGet ( Int16 nPlayerIndex, Int16 nChannel, Int32 nStartPos, Int32 nEndPos, bool bValueInPerc, Int16 __gc[] pBufferMin, Int16 __gc[] pBufferMax, Int32 nBufferLength ); |
Parameter |
Description |
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nPlayerIndex |
Number representing the zero-based index of the player that will use the waveform. |
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nChannel |
Number representing the audio channel we are interested in. Can be a value between 0 and 7. |
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nStartPos |
Number representing the start position, expressed in milliseconds, where we want to get waveform's peaks. The value 0 represents the sound's beginning. |
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nEndPos |
Number representing the end position, expressed in milliseconds, where we want to get waveform's peaks. The value -1 represents the sound's end. |
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bValueInPerc |
Boolean value that specifies if the given buffers should be filled with values expressed in percentage. Supported values are the following:
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pBufferMin |
Variant parameter containing the pointer to the buffer that, on return from the method call, will contain the min waveform peaks. |
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pBufferMax |
Variant parameter containing the pointer to the buffer that, on return from the method call, will contain the max waveform peaks. |
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nBufferLength |
Length in bytes of the given buffers previously obtained through the Waveform.PeaksBufferLengthGet method. |
Return value
Value |
Meaning |
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Negative value |
An error occurred (see the LastError property for further error details) |
enumErrorCodes.NOERROR (0) |
The method call was successful. |
Samples
Below you can find a couple of samples that demonstrate how to load waveform peaks in Visual Basic.NET and Visual C#
Visual Basic.NET
' memory buffers must be declared as global variables
Dim m_bufferMin() As Int16
Dim m_bufferMax() As Int16
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
' get the size in bytes of the buffers
Dim nBufferLength As Int32 = 0
AudioDjStudio1.DisplayWaveform.PeaksBufferLengthGet (0, nStartPosInMs, nEndPosInMs, nBufferLength)
' reallocate the memory buffer space and store the song
ReDim m_bufferMin(nBufferLength/2)
ReDim m_bufferMax(nBufferLength/2)
' fill the buffers with peaks data
AudioDjStudio1.DisplayWaveform.PeaksBufferGet (0, 0, nStartPosInMs, nEndPosInMs, true, m_bufferMin, m_bufferMax, nBufferLength)
End Sub
Visual C#.NET
// declare the memory buffer (cannot be a local variable)
Int16[] m_bufferMin = null;
Int16[] m_bufferMax = null;
private void buttonLoad1_Click(object sender, System.EventArgs e)
{
// get the size in bytes of the buffers
Int32 nBufferLength = 0;
AudioDjStudio1.DisplayWaveform.PeaksBufferLengthGet (0, nStartPosInMs, nEndPosInMs, ref nBufferLength);
// reallocate the memory buffer space and store the song
m_bufferMin = new Int16[nBufferLength/2];
m_bufferMax = new Int16[nBufferLength/2];
// fill the buffers with peaks data
AudioDjStudio1.DisplayWaveform.PeaksBufferGet (0, 0, nStartPosInMs, nEndPosInMs, true, m_bufferMin, m_bufferMax, nBufferLength);
}
