def normalize_imagenet(x):
    """ Normalize input images according to ImageNet standards.
    Args:
        x (tensor): input images
    """
    x = x.clone()
    x[:, 0] = (x[:, 0] - 0.485) / 0.229
    x[:, 1] = (x[:, 1] - 0.456) / 0.224
    x[:, 2] = (x[:, 2] - 0.406) / 0.225
    return x