[vtkusers] creating vtkImageData from byte array in Java

[Oliver Vidovic]

 Hi vtkusers,

 How can I create vtkImageData from a byte array? I know this works:

-- begin code

	public void createImageDataFromByteArray( byte[] data )
	{
		vtkImageData image = new vtkImageData();
		image.SetDimensions( xsize, ysize, zsize );
		image.SetExtent( xmin, xmax, ymin, ymax, zmin, zmax );
		image.SetNumberOfScalarComponents( 1 );
		image.SetOrigin( xorigin, yorigin, zorigin );
		image.SetSpacing( xspacing, yspacing, zspacing );
		image.SetScalarType( 3 ); // VTK_UNSIGNED_CHAR

		// set values
		vtkScalars scalars = new vtkScalars();
		scalars.SetNumberOfComponents( 1 );
		scalars.SetDataTypeToUnsignedChar();

		int index = 0;
		for ( int x = 0; x < xsize; x++ )
		{
			for ( int y = 0; y < ysize; y++ )
			{
				for ( int z = 0; z < zsize; z++ )
				{
					scalars.InsertNextScalar( data[ index ] );
					index++;
				}
			}
		}
		image.GetPointData().SetScalars( scalars );

		return image;
	} // end method

-- end code

 However, with this approach I have to loop through all the data in the byte
array and assign it to vtkScalars. Since I am working with 25 - 50 MB byte
arrays, is there a faster/better/smarter way to do this?

 In C++ there is a class vtkImageImport and methods that can take void* to
the data, but those methods are not exposed in Java. Any reason why they are
not exposed? Can I expose them using JNI? Will there be any known problems?
Has anyone done it before?

 Note: I am using vtk 3.2 and Java 1.3.




 thanks
 oliver