diff --git a/MagickCore/effect.c b/MagickCore/effect.c
index b7757a6..26492ee 100644
--- a/MagickCore/effect.c
+++ b/MagickCore/effect.c
@@ -2615,8 +2615,8 @@
preview_image=CloneImage(thumbnail,0,0,MagickTrue,exception);
if (preview_image == (Image *) NULL)
break;
- (void) BilevelImage(thumbnail,
- (double) (percentage*((MagickRealType) QuantumRange+1.0))/100.0);
+ (void) BilevelImage(thumbnail,(double) (percentage*((MagickRealType)
+ QuantumRange+1.0))/100.0,exception);
(void) FormatLocaleString(label,MaxTextExtent,"threshold %g",
(double) (percentage*((MagickRealType) QuantumRange+1.0))/100.0);
break;