diff --git a/coders/aai.c b/coders/aai.c
index 66f0c70..0f34b75 100644
--- a/coders/aai.c
+++ b/coders/aai.c
@@ -391,7 +391,7 @@
         *q++=ScaleQuantumToChar(GetPixelBlue(image,p));
         *q++=ScaleQuantumToChar(GetPixelGreen(image,p));
         *q++=ScaleQuantumToChar(GetPixelRed(image,p));
-        *q=ScaleQuantumToChar((Quantum) (image->alpha_trait == BlendPixelTrait ?
+        *q=ScaleQuantumToChar((Quantum) (image->alpha_trait != UndefinedPixelTrait ?
           GetPixelAlpha(image,p) : OpaqueAlpha));
         if (*q == 255)
           *q=254;