if Action_PreviewCurve.checked then
    IEColorCurve.PreviewImageEnView := imageenview
  else
  begin
    IEColorCurve.Clear();
    IEColorCurve.PreviewImageEnView := nil;
  end;
  imageenview.Update();

// Checkbox code to enable or disable the Color Curve
procedure TfrmCurves.chkEnableColorCurveClick(Sender: TObject);
begin
  if chkEnableColorCurve.Checked then
  begin
    IEColorCurve1.AssignSource(imgPreview.IEBitmap);
    IEColorCurve1.Enabled := True;
  end
  else
  begin
    IEColorCurve1.Clear();
    IEColorCurve1.ResetAllCurves();
    IEColorCurve1.Enabled := False;
  end;
end;