double *range = im->GetScalarRange();
mViewer->SetColorWindow(range[1] - range[0]);
mViewer->SetColorLevel(0.5 * (range[1] + range[0]));
double *range = im->GetScalarRange();
mViewer->SetColorWindow(range[1] - range[0]);
mViewer->SetColorLevel(0.5 * (range[1] + range[0]));