vf_delogo: fix order of operations in apply_delogo()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavfilter/vf_delogo.c

@@ -80,12 +80,12 @@ static void apply_delogo(uint8_t *dst, int dst_linesize,
     topright = src+logo_y1     * src_linesize+logo_x2-1;
     botleft  = src+(logo_y2-1) * src_linesize+logo_x1;
 
-    dst += (logo_y1+1)*dst_linesize;
-    src += (logo_y1+1)*src_linesize;
-
     if (!direct)
         av_image_copy_plane(dst, dst_linesize, src, src_linesize, w, h);
 
+    dst += (logo_y1+1)*dst_linesize;
+    src += (logo_y1+1)*src_linesize;
+
     for (y = logo_y1+1; y < logo_y2-1; y++) {
         for (x = logo_x1+1,
              xdst = dst+logo_x1+1,