Index: trunk/pswarp/src/pswarpTransformReadout.c
===================================================================
--- trunk/pswarp/src/pswarpTransformReadout.c	(revision 20312)
+++ trunk/pswarp/src/pswarpTransformReadout.c	(revision 20334)
@@ -63,4 +63,9 @@
     pswarpMapGridSetGrid(grid, xOutMax, yOutMax, &xGrid, &yGrid);
     CHECK_GRID_RANGE();
+
+    if (!pmReadoutMaskNonfinite(input, pmConfigMaskGet("SAT", config))) {
+        psError(PS_ERR_UNKNOWN, false, "Unable to mask non-finite pixels in input.");
+        return false;
+    }
 
     // Interpolation options : move these from the arguments to explicit assignments