Index: trunk/ppStack/src/ppStackSources.c
===================================================================
--- trunk/ppStack/src/ppStackSources.c	(revision 27447)
+++ trunk/ppStack/src/ppStackSources.c	(revision 27725)
@@ -230,6 +230,10 @@
             sources = sourceLists->data[i];
         }
+        options->quality = PPSTACK_ERR_REJECTED;
         options->sources = psMemIncrRefCounter(sources);
-        psLogMsg("ppStack", PS_LOG_WARN, "Single image with sources --- no need to match transparency.");
+        options->norm = psVectorAlloc(num, PS_TYPE_F32);
+        psVectorInit(options->norm, 1.0);
+        options->zp = NAN;
+        psLogMsg("ppStack", PS_LOG_WARN, "Single image with sources --- cannot match transparency.");
         psFree(zp);
         psFree(zpExp);