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The NoData mask for a specified plane.
[Visual Basic .NET] Public Function get_NoDataMask ( _ ByVal plane As Integer _ ) As Object
[Visual Basic .NET] Public Sub set_NoDataMask ( _ ByVal plane As Integer, _ ByVal pVal As Object _ )
[C#] public object get_NoDataMask ( int plane );
[C#] public void set_NoDataMask ( int plane, object pVal );
[C++]
HRESULT get_NoDataMask(
long plane,
VARIANT pVal
);
[C++]
HRESULT put_NoDataMask(
long plane,
Variant* pVal
);
[C++]
Parameters plane [in]
plane is a parameter of type long pVal [in]
pVal is a parameter of type VARIANT plane [in]
plane is a parameter of type long pVal [out, retval]
pVal is a parameter of type VARIANT*
Conceptually, a NoData mask is a two-dimensional array with values 0 and 1. Each element in the two-dimensional array is correspondent to a pixel in a raster; 1 indicates the pixel is a value pixel and 0 means the pixel is NoData.
In order to save space, the NoData mask is actually stored as a one-dimensional array of byte. Each byte is used to represent NoData value flags for 8 correspondent pixels.
If the image (or SafeArray) has an dimension of nxn, the length of the array returned from NoDataMask will be (n*n+7)/7