diff --git a/libavutil/imgutils.c b/libavutil/imgutils.c
index 4096c0da66..e592f7976a 100644
--- a/libavutil/imgutils.c
+++ b/libavutil/imgutils.c
@@ -167,7 +167,7 @@ int av_image_fill_pointers(uint8_t *data[4], enum AVPixelFormat pix_fmt, int hei
     memset(data , 0, sizeof(data[0])*4);
 
     data[0] = ptr;
-    for (i = 1; i < 4 && sizes[i - 1] > 0; i++)
+    for (i = 1; i < 4 && sizes[i]; i++)
         data[i] = data[i - 1] + sizes[i - 1];
 
     return ret;