of two image patches for some pre-defined network. This measure has been shown to match human perception well. A low LPIPS score means that image patches are perceptual similar. Both input image patches are expected to have shape ``(N, 3, H, W)``. The minimum size of `H, W` depends on the chosen backbone (see `net_type` arg). Args: img1: first set of images img2: second set of images net_type: str indicating backbone network type to use. Choose between `'alex'`, `'vgg'` or `'squeeze'` reduction: str indicating how to reduce over the batch dimension. Choose between `'sum'` or `'mean'`. normalize: by default this is ``False`` meaning that the input is expected to be in the [-1,1] range. If set to ``True`` will instead expect input to be in the ``[0,1]`` range. Example: >>> import torch >>> _ = torch.manual_seed(123) >>> from torchmetrics.functional.image.lpips import learned_perceptual_image_patch_similarity >>> img1 = (torch.rand(10, 3, 100, 100) * 2) - 1 >>> img2 = (torch.rand(10, 3, 100, 100) * 2) - 1 >>> learned_perceptual_image_patch_similarity(img1, img2, net_type='squeeze') tensor(0.1008, grad_fn=) )