perceptual-loss_.py

    def forward(self, input, target):
        res = [F.l1_loss(input, target) / 100]  # pixel loss
        in_fts = self.make_fts(input, True) # extracting activations for predicted image
        out_fts = self.make_fts(target) # extracting activations for ground-truth image
        res+= [F.l1_loss(inp, targ.features) * w
               for inp, targ, w in zip(in_fts, out_fts, self.wgts)] # Perceptual loss
        return sum(res)

    def close(self):
        for o in self.sfs: o.remove() # This removes the activations from your memory.