- the conv filter now enforces that the sum of the coefficients is

[imager.git] / lib / Imager / Filters.pod

diff --git a/lib/Imager/Filters.pod b/lib/Imager/Filters.pod
index 6939501abc03add0ca297a8c104fe63285b1fafa..89810766477b3d138c1cf6b261e1b617cf83207e 100644 (file)
--- a/lib/Imager/Filters.pod
+++ b/lib/Imager/Filters.pod
@@ -198,6 +198,10 @@ coefficients must be non-zero.
   $img->filter(type=>"conv", coef=>[ 1, 2, 1 ])
     or die $img->errstr;
 
+  # error
+  $img->filter(type=>"conv", coef=>[ -0.5, 1, -0.5 ])
+    or die $img->errstr;
+
 =item fountain
 
 renders a fountain fill, similar to the gradient tool in most paint