diff --git a/src/libImaging/Jpeg2KEncode.c b/src/libImaging/Jpeg2KEncode.c
index 0d7e896b7..de8586706 100644
--- a/src/libImaging/Jpeg2KEncode.c
+++ b/src/libImaging/Jpeg2KEncode.c
@@ -464,7 +464,7 @@ j2k_encode_entry(Imaging im, ImagingCodecState state) {
     }
 
     if (!context->num_resolutions) {
-        while (tile_width < (1 << (params.numresolution - 1U)) || tile_height < (1 << (params.numresolution - 1U))) {
+        while (tile_width < (1U << (params.numresolution - 1U)) || tile_height < (1U << (params.numresolution - 1U))) {
             params.numresolution -= 1;
         }
     }