Index: trunk/ppMerge/src/ppMergeArguments.c
===================================================================
--- trunk/ppMerge/src/ppMergeArguments.c	(revision 17227)
+++ trunk/ppMerge/src/ppMergeArguments.c	(revision 18060)
@@ -248,5 +248,5 @@
     VALUE_ARG_RECIPE_FLOAT("-mask-suspect", "MASK.SUSPECT", F32);
     VALUE_ARG_RECIPE_FLOAT("-mask-bad",     "MASK.BAD",     F32);
-    VALUE_ARG_RECIPE_INT("-mask-grow",      "MASK.GROW",    S32, 0);
+    VALUE_ARG_RECIPE_INT("-mask-grow",      "MASK.GROW",    S32, -1);
     VALUE_ARG_RECIPE_MASK("-mask-growval",  "MASK.GROWVAL");
     VALUE_ARG_RECIPE_BOOL("-mask-chip",     "MASK.CHIPSTATS");