class_docstr: Layer to compute the SSIM loss between a pair of images
      
class_docstr_tok: ["Layer","to","compute","the","SSIM","loss","between","a","pair","of","images"]
code: def __init__(self):
      super(SSIM, self).__init__()
      self.mu_x_pool = nn.AvgPool2D(3, 1)
      self.mu_y_pool = nn.AvgPool2D(3, 1)
      self.sig_x_pool = nn.AvgPool2D(3, 1)
      self.sig_y_pool = nn.AvgPool2D(3, 1)
      self.sig_xy_pool = nn.AvgPool2D(3, 1)
  
      self.refl = nn.ReflectionPad2D(1)
  
      self.C1 = 0.01**2
      self.C2 = 0.03**2
  
imports: from __future__ import absolute_import, division, print_function
  import numpy
  import mxnet
  from mxnet.gluon import nn
label_desc: Use image node_id 1 to create a new SSIM object from inherited base classes: nn with example: obj = SSIM()