diff --git a/include/avif/avif.h b/include/avif/avif.h
index 3716cb66f2..ee77887b55 100644
--- a/include/avif/avif.h
+++ b/include/avif/avif.h
@@ -387,8 +387,8 @@ enum
     AVIF_MATRIX_COEFFICIENTS_CHROMA_DERIVED_NCL = 12,
     AVIF_MATRIX_COEFFICIENTS_CHROMA_DERIVED_CL = 13,
     AVIF_MATRIX_COEFFICIENTS_ICTCP = 14,
-    AVIF_MATRIX_COEFFICIENTS_YCGCO_RE = 15,
-    AVIF_MATRIX_COEFFICIENTS_YCGCO_RO = 16,
+    AVIF_MATRIX_COEFFICIENTS_YCGCO_RE = 16,
+    AVIF_MATRIX_COEFFICIENTS_YCGCO_RO = 17,
     AVIF_MATRIX_COEFFICIENTS_LAST
 };
 typedef uint16_t avifMatrixCoefficients; // AVIF_MATRIX_COEFFICIENTS_*