code: def total_edge_pixels_from_mask(mask):
      
  
      border_pixel_total = 0
  
      for y in range(mask.shape[0]):
          for x in range(mask.shape[1]):
              if not mask[y, x]:
                  if mask[y + 1, x] or mask[y - 1, x] or mask[y, x + 1] or mask[y, x - 1] or \
                          mask[y + 1, x + 1] or mask[y + 1, x - 1] or mask[y - 1, x + 1] or mask[y - 1, x - 1]:
                      border_pixel_total += 1
  
      return border_pixel_total
docs: Compute the total number of borders-pixels in a masks.