diff --git a/src/image.c b/src/image.c
index c08b898e7d8da959aeed5bc4151b7083f8dd8b3a..866323ba6e54409cb9f140d5e5741931bb846ec1 100644
--- a/src/image.c
+++ b/src/image.c
@@ -2151,8 +2151,8 @@ image_set_rotation (struct image *img, matrix3x3 tm)
   matrix3x3_mult (rot, tmp, tmp2);
 
   /* Translate back.  */
-  t[2][0] = - (width * .5);
-  t[2][1] = - (height * .5);
+  t[2][0] = width * -.5;
+  t[2][1] = height * -.5;
   matrix3x3_mult (t, tmp2, tm);
 
   img->width = width;