cope with unusual image modes

screenless/bureau/publicrelations/publicrelations.py

@@ -113,7 +113,8 @@ class PublicRelations(Bureau):
                     print("fetching", i_url, filename)
                     urllib.request.urlretrieve(i_url, filename)
                     im = PIL.Image.open(filename)
-                    im = PIL.ImageOps.equalize(im)
+                    if im.mode in ("L", "RGB", "P"):
+                        im = PIL.ImageOps.equalize(im)
                     im.thumbnail((576, 576), PIL.Image.ANTIALIAS)
                     prn.image(im, impl="bitImageColumn")