Index: trunk/psModules/src/camera/pmFPAfileDefine.c
===================================================================
--- trunk/psModules/src/camera/pmFPAfileDefine.c	(revision 23275)
+++ trunk/psModules/src/camera/pmFPAfileDefine.c	(revision 23328)
@@ -1006,6 +1006,9 @@
     PS_ASSERT_STRING_NON_EMPTY(filename, NULL);
 
-    pmFPAfile *file = pmFPAfileDefineOutputForFormat(config, NULL, filename, src->cameraName,
-                                                     src->formatName);
+    pmFPAfile *file = pmFPAfileDefineOutputForFormat(config, NULL, filename, src->cameraName, src->formatName);
+    if (!file) {
+        psError(PS_ERR_UNEXPECTED_NULL, false, "file %s not defined\n", filename);
+        return NULL;
+    }
     file->src = psMemIncrRefCounter(src->fpa); // inherit output elements from this source pmFPA
     file->xBin = xBin;