Fix brightness filter (argument ingnored)

diff --git a/ext/gd/libgd/gd.c b/ext/gd/libgd/gd.c
index b82ab51382eedd1e3d93814440eff48162eaabd0..96684eab6c1b9bf2766aaefda66a24954beea8eb 100644 (file)
--- a/ext/gd/libgd/gd.c
+++ b/ext/gd/libgd/gd.c
@@ -3410,7 +3410,7 @@ int gdImageContrast(gdImagePtr src, double contrast)
                return 0;
        }
        
-       contrast = (double)(100.0-80.0)/100.0;
+       contrast = (double)(100.0-contrast)/100.0;
        contrast = contrast*contrast;
        
        for (y=0; y<src->sy; ++y) {