diff --git a/libavcodec/exr.c b/libavcodec/exr.c
index dd5924245f..f338ff0085 100644
--- a/libavcodec/exr.c
+++ b/libavcodec/exr.c
@@ -1833,8 +1833,8 @@ static int decode_header(EXRContext *s, AVFrame *frame)
             dx = bytestream2_get_le32(gb);
             dy = bytestream2_get_le32(gb);
 
-            s->w = dx - sx + 1;
-            s->h = dy - sy + 1;
+            s->w = (unsigned)dx - sx + 1;
+            s->h = (unsigned)dy - sy + 1;
 
             continue;
         } else if ((var_size = check_header_variable(s, "lineOrder",