diff --git a/PIL/JpegImagePlugin.py b/PIL/JpegImagePlugin.py
index b1c25db1d..38e4a5f87 100644
--- a/PIL/JpegImagePlugin.py
+++ b/PIL/JpegImagePlugin.py
@@ -422,6 +422,9 @@ def _getexif(self):
         exif[key] = _fixup(value)
     # get exif extension
     try:
+        # exif field 0x8769 is an offset pointer to the location
+        # of the nested embedded exif ifd.
+        # It should be a long, but may be corrupted.
         file.seek(exif[0x8769])
     except (KeyError, TypeError):
         pass
@@ -432,7 +435,10 @@ def _getexif(self):
             exif[key] = _fixup(value)
     # get gpsinfo extension
     try:
-        file.seek(exif[0x8825])
+        # exif field 0x8825 is an offset pointer to the location
+        # of the nested embedded gps exif ifd. 
+        # It should be a long, but may be corrupted.
+      file.seek(exif[0x8825])
     except (KeyError, TypeError):
         pass
     else: