diff -u base/plugins/perspective/perspective.C hvirtual-1.1.6/plugins/perspective/perspective.C
--- base/plugins/perspective/perspective.C	2003-06-16 22:00:51.000000000 +0200
+++ hvirtual-1.1.6/plugins/perspective/perspective.C	2003-07-17 21:10:19.000000000 +0200
@@ -946,7 +946,7 @@
 				chroma_offset; \
 			if(components == 4) \
 			{ \
-				out_row[2] = (in_row1[3] +  \
+				out_row[3] = (in_row1[3] +  \
 						in_row1[components + 3] +  \
 						in_row2[3] +  \
 						in_row2[components + 3]) /  \