diff --git a/src/avif.c b/src/avif.c
index 8fa2b36..e74aba7 100644
--- a/src/avif.c
+++ b/src/avif.c
@@ -255,7 +255,10 @@
     avifPixelFormatInfo formatInfo;
     avifGetPixelFormatInfo(srcImage->yuvFormat, &formatInfo);
     if ((rect->width > srcImage->width) || (rect->height > srcImage->height) || (rect->x > (srcImage->width - rect->width)) ||
-        (rect->y > (srcImage->height - rect->height)) || (rect->x & formatInfo.chromaShiftX) || (rect->y & formatInfo.chromaShiftY)) {
+        (rect->y > (srcImage->height - rect->height))) {
+        return AVIF_RESULT_INVALID_ARGUMENT;
+    }
+    if (!formatInfo.monochrome && ((rect->x & formatInfo.chromaShiftX) || (rect->y & formatInfo.chromaShiftY))) {
         return AVIF_RESULT_INVALID_ARGUMENT;
     }
     avifImageFreePlanes(dstImage, AVIF_PLANES_ALL); // dstImage->imageOwnsYUVPlanes and dstImage->imageOwnsAlphaPlane set to AVIF_FALSE.