diff --git a/src/libImaging/Reduce.c b/src/libImaging/Reduce.c
index 022daa000..a4e58ced8 100644
--- a/src/libImaging/Reduce.c
+++ b/src/libImaging/Reduce.c
@@ -1452,7 +1452,7 @@ ImagingReduce(Imaging imIn, int xscale, int yscale, int box[4]) {
     ImagingSectionCookie cookie;
     Imaging imOut = NULL;
 
-    if (strcmp(imIn->mode, "P") == 0 || strcmp(imIn->mode, "1") == 0) {
+    if (imIn->mode == IMAGING_MODE_P || imIn->mode == IMAGING_MODE_1) {
         return (Imaging)ImagingError_ModeError();
     }