diff --git a/include/gdiplusflat.h b/include/gdiplusflat.h
index 8e9812f..803ea1a 100644
--- a/include/gdiplusflat.h
+++ b/include/gdiplusflat.h
@@ -39,6 +39,7 @@
 GpStatus WINGDIPAPI GdipSetAdjustableArrowCapWidth(GpAdjustableArrowCap*,REAL);
 
 /* Bitmap */
+GpStatus WINGDIPAPI GdipBitmapApplyEffect(GpBitmap*,CGpEffect*,RECT*,BOOL,VOID**,INT*);
 GpStatus WINGDIPAPI GdipBitmapGetPixel(GpBitmap*,INT,INT,ARGB*);
 GpStatus WINGDIPAPI GdipBitmapLockBits(GpBitmap*,GDIPCONST GpRect*,UINT,
     PixelFormat,BitmapData*);