public double[,] GetAffineTransform(double[,] quad)
{
double[,] coeffs = new double[2, 3];
NppiRect rect = new NppiRect(_pointRoi, _sizeRoi);
status = NPPNativeMethods.NPPi.AffinTransforms.nppiGetAffineTransform(rect, quad, coeffs);
Debug.WriteLine(String.Format("{0:G}, {1}: {2}", DateTime.Now, "nppiGetAffineTransform", status));
NPPException.CheckNppStatus(status, this);
return coeffs;
}