Index: trunk/ppStats/src/ppStatsReadout.c
===================================================================
--- trunk/ppStats/src/ppStatsReadout.c	(revision 14359)
+++ trunk/ppStats/src/ppStatsReadout.c	(revision 14392)
@@ -71,5 +71,6 @@
             int x = j % image->numCols;
             sampleValues->data.F32[i] = image->data.F32[y][x];
-            if (!isfinite(sampleValues->data.F32[i])) {
+            if (mask && (!mask->data.PS_TYPE_MASK_DATA[y][x] & maskVal) &&
+                !isfinite(sampleValues->data.F32[i])) {
                 if (!warnNonFinite) {
                     psWarning("Non-finite value detected at %d,%d", x, y);