code: public static void shiftZeroFrequency(ImageInterleaved transform, boolean forward ) {
  		if( transform instanceof InterleavedF32 ) {
  			DiscreteFourierTransformOps.shiftZeroFrequency((InterleavedF32) transform, forward);
  		} else if( transform instanceof InterleavedF64 ) {
  			DiscreteFourierTransformOps.shiftZeroFrequency((InterleavedF64)transform,forward);
  		} else {
  			throw new IllegalArgumentException("Unknown image type");
  		}
  	}
docs: Moves the zero-frequency component into the image center (width/2,height/2).   This function can
  be called to undo the transform.
  
  @param transform the DFT which is to be shifted.
  @param forward If true then it does the shift in the forward direction.  If false then it undoes the transforms.