diff --git a/wand/compare.c b/wand/compare.c
index 3396d4a..e529948 100644
--- a/wand/compare.c
+++ b/wand/compare.c
@@ -446,6 +446,8 @@
                 argv[i]);
             break;
           }
+        if (LocaleCompare("concurrent",option+1) == 0)
+          break;
         ThrowCompareException(OptionError,"UnrecognizedOption",option)
       }
       case 'd':
@@ -529,6 +531,17 @@
               dissimilarity_threshold=atof(argv[i]);
             break;
           }
+        if (LocaleCompare("duration",option+1) == 0)
+          {
+            if (*option == '+')
+              break;
+            i++;
+            if (i == (long) (argc-1))
+              ThrowCompareException(OptionError,"MissingArgument",option);
+            if (IsGeometry(argv[i]) == MagickFalse)
+              ThrowCompareInvalidArgumentException(option,argv[i]);
+            break;
+          }
         ThrowCompareException(OptionError,"UnrecognizedOption",option)
       }
       case 'e':