doc/filters: add RGB geq example
authorStefano Sabatini <stefasab@gmail.com>
Sun, 19 May 2013 20:54:49 +0000 (22:54 +0200)
committerStefano Sabatini <stefasab@gmail.com>
Mon, 20 May 2013 09:12:09 +0000 (11:12 +0200)
doc/filters.texi

index cc71a2f..301887d 100644 (file)
@@ -4111,6 +4111,12 @@ Generate a quick emboss effect:
 @example
 format=gray,geq=lum_expr='(p(X,Y)+(256-p(X-4,Y-4)))/2'
 @end example
+
+@item
+Modify RGB components depending on pixel position:
+@example
+geq=r='X/W*r(X,Y)':g='(1-X/W)*g(X,Y)':b='(H-Y)/H*b(X,Y)'
+@end example
 @end itemize
 
 @section gradfun