code: def mse(vref, vcmp):
      
  
      r = np.asarray(vref, dtype=np.float64).ravel()
      c = np.asarray(vcmp, dtype=np.float64).ravel()
      return np.mean(np.abs(r - c)**2)
docs: Compute Mean Squared Error (MSE) between two images.
  
      Parameters
      ----------
      vref : array_like
        Reference image
      vcmp : array_like
        Comparison image
  
      Returns
      -------
      x : float
        MSE between `vref` and `vcmp`