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LoadSoundChannelFromMemory method

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Remarks

 

Loads a specific audio channel from the sound file stored inside a memory buffer for editing purposes. The sound file can be a stream file or a MOD music file (see the LoadSound method for supported formats).

 

You can manage how loaded sound will be added to the existing editing session through a previous call to the SetLoadingMode method.

You can limit the range of sound data that will be loaded from the given sound file with a previous call to the SetLoadingRange method.

 

For loading a channel from files in RAW format use the LoadSoundChannelFromRawMemory method.

 

During the execution of the loading session the CallbackPercentage delegate is invoked, with the nOperation parameter set to OPERATION_SOUND_LOADING, in order to notify about the percentage of advancement of the loading session.

 

For further details about callback delegates see the How to synchronize the container application with the API tutorial.

 

IMPORTANT TOPIC: remember that the memory buffer containing song data must not be moved by the garbage collector and needs to be available till the call to the CloseSound method.

 

 

Syntax

 

[Visual Basic]

Public Function LoadSoundChannelFromMemory (

pBuffer() as Byte,

nBufferLength as Int32,

nChannel as Int16

) as enumErrorCodes


 

[C#]

public enumErrorCodes LoadSoundChannelFromMemory (

byte[] pBuffer,

Int32 nBufferLength,

Int16 nChannel

);


 

[C++]

public: enumErrorCodes LoadSoundChannelFromMemory (

unsigned char __gc[] pBuffer,

Int32 nBufferLength,

Int16 nChannel

);


 

 

Parameter

Description

 

 

pBuffer

Input buffer containing the original sound

nBufferLength

Length of the input buffer expressed in bytes

nChannel

Number representing the zero-based index of the audio channel to load.

 

 

Return value

 

Value

Meaning

 

 

Negative value

An error occurred (see the LastError property for further error details)

enumErrorCodes.ERR_NOERROR (0)

The method call was successful.

 

 

Sample

 

Below you can find a couple of samples that demonstrate how to load a sound stored in memory in Visual Basic.NET and Visual C# : in these samples the file is taken from a file and its contents are stored in memory.

 

Visual Basic.NET

 

' declare the memory buffer (cannot be a local variable)

Dim m_byteBuffer() As Byte

 

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

Dim openFileDialog1 As New OpenFileDialog

If openFileDialog1.ShowDialog() <> DialogResult.OK Then

    Return

End If

 

' put the song file into a stream

Dim streamFile As FileStream

streamFile = New FileStream(openFileDialog1.FileName, FileMode.Open)

Dim binReader As BinaryReader

binReader = New BinaryReader(streamFile)

 

' reallocate the memory buffer space and store the song

ReDim m_byteBuffer(streamFile.Length)

binReader.Read(m_byteBuffer, 0, streamFile.Length)

 

If audioSoundEditor1.LoadSoundFromMemory(m_byteBuffer, streamFile.Length) = AudioSoundEditor.enumErrorCodes.ERR_NOERROR Then

    ' do domething

    ....

End If

End Sub

 

 

Visual C#.NET

 

// declare the memory buffer (cannot be a local variable)

byte[] m_byteBuffer = null;

 

private void buttonLoad1_Click(object sender, System.EventArgs e)

{

OpenFileDialog openFileDialog1 = new OpenFileDialog();

if (openFileDialog1.ShowDialog() != DialogResult.OK)

    return;

 

// put the song file into a stream

FileStream      streamFile = new FileStream (openFileDialog1.FileName, FileMode.Open);

BinaryReader    binReader = new BinaryReader (streamFile);

 

//  allocate the memory buffer space and store the song

m_byteBuffer = new byte[streamFile.Length];

binReader.Read (m_byteBuffer, 0, (int) streamFile.Length);

 

// load song from memory buffer

if (audioSoundEditor1.LoadSoundFromMemory (m_byteBuffer, (Int32) streamFile.Length) == AudioSoundEditor.enumErrorCodes.ERR_NOERROR)

{

    // do something

    ...

}

}