diff --git a/libavcodec/h263dec.c b/libavcodec/h263dec.c
index 3fe37e95a8..faa54f57e1 100644
--- a/libavcodec/h263dec.c
+++ b/libavcodec/h263dec.c
@@ -762,8 +762,8 @@ intrax8_decoded:
             int x, y, p;
             av_frame_make_writable(pict);
             for (p=0; p<3; p++) {
-                int w = -((-pict-> width)>>!!p);
-                int h = -((-pict->height)>>!!p);
+                int w = FF_CEIL_RSHIFT(pict-> width, !!p);
+                int h = FF_CEIL_RSHIFT(pict->height, !!p);
                 int linesize = pict->linesize[p];
                 for (y=0; y<(h>>1); y++)
                     for (x=0; x<w; x++)