code: def load_depth(self, idx):
          
          im = Image.open('{}/data/depth/img_{}.png'.format(self.nyud_dir, idx))
          d = np.array(im, dtype=np.float32)
          d = np.log(d)
          d -= self.mean_logd
          d = d[np.newaxis, ...]
          return d
docs: Load pre-processed depth for NYUDv2 segmentation set.