diff --git a/src/PIL/TiffImagePlugin.py b/src/PIL/TiffImagePlugin.py
index 3a2bd7b4c..977d1da14 100644
--- a/src/PIL/TiffImagePlugin.py
+++ b/src/PIL/TiffImagePlugin.py
@@ -257,14 +257,15 @@ OPEN_INFO = {
     (II, 5, (1,), 1, (8, 8, 8, 8, 8, 8), (0, 0)): ("CMYK", "CMYKXX"),
     (MM, 5, (1,), 1, (8, 8, 8, 8, 8, 8), (0, 0)): ("CMYK", "CMYKXX"),
 
+    # JPEG compressed images handled by LibTiff and auto-converted to RGB
     (II, 6, (1,), 1, (8, 8, 8), ()): ("RGB", "RGB"),
     (MM, 6, (1,), 1, (8, 8, 8), ()): ("RGB", "RGB"),
-    (II, 6, (1,), 1, (8, 8, 8, 8), (0,)): ("RGBX", "RGBX"),
-    (MM, 6, (1,), 1, (8, 8, 8, 8), (0,)): ("RGBX", "RGBX"),
-    (II, 6, (1,), 1, (8, 8, 8, 8, 8), (0, 0)): ("RGBX", "RGBXX"),
-    (MM, 6, (1,), 1, (8, 8, 8, 8, 8), (0, 0)): ("RGBX", "RGBXX"),
-    (II, 6, (1,), 1, (8, 8, 8, 8, 8, 8), (0, 0, 0)): ("RGBX", "RGBXXX"),
-    (MM, 6, (1,), 1, (8, 8, 8, 8, 8, 8), (0, 0, 0)): ("RGBX", "RGBXXX"),
+    (II, 6, (1,), 1, (8, 8, 8, 8), (0,)): ("RGB", "RGB"),
+    (MM, 6, (1,), 1, (8, 8, 8, 8), (0,)): ("RGB", "RGB"),
+    (II, 6, (1,), 1, (8, 8, 8, 8, 8), (0, 0)): ("RGB", "RGB"),
+    (MM, 6, (1,), 1, (8, 8, 8, 8, 8), (0, 0)): ("RGB", "RGB"),
+    (II, 6, (1,), 1, (8, 8, 8, 8, 8, 8), (0, 0, 0)): ("RGB", "RGB"),
+    (MM, 6, (1,), 1, (8, 8, 8, 8, 8, 8), (0, 0, 0)): ("RGB", "RGB"),
 
     (II, 8, (1,), 1, (8, 8, 8), ()): ("LAB", "LAB"),
     (MM, 8, (1,), 1, (8, 8, 8), ()): ("LAB", "LAB"),