diff --git a/libavcodec/gdv.c b/libavcodec/gdv.c
index 1efc64b1dc..595d8ff4e4 100644
--- a/libavcodec/gdv.c
+++ b/libavcodec/gdv.c
@@ -85,8 +85,7 @@ static void rescale(GDVContext *gdv, uint8_t *dst, int w, int h, int scale_v, in
             int y = h - j - 1;
             uint8_t *dst1 = dst + PREAMBLE_SIZE + y * w;
             uint8_t *src1 = dst + PREAMBLE_SIZE + (y>>!!gdv->scale_h) * (w>>1);
-            for (i = 0; i < w; i++) {
-                int x = w - i - 1;
+            for (x = w - 1; x >= 0; x--) {
                 dst1[x] = src1[(x>>1)];
             }
         }