code: public static void determinant(GrayF32 featureIntensity , GrayF32 hessianXX, GrayF32 hessianYY , GrayF32 hessianXY )
  	{
  		InputSanityCheck.checkSameShape(featureIntensity,hessianXX,hessianYY,hessianXY);
  
  		ImplHessianBlobIntensity.determinant(featureIntensity,hessianXX,hessianYY,hessianXY);
  	}
docs: Feature intensity using the Hessian matrix's determinant.
  
  @param featureIntensity Output feature intensity. Modified.
  @param hessianXX Second derivative along x-axis. Not modified.
  @param hessianYY Second derivative along y-axis. Not modified.
  @param hessianXY Second derivative along x-axis and y-axis. Not modified.