Index: trunk/psModules/src/detrend/pmBias.c
===================================================================
--- trunk/psModules/src/detrend/pmBias.c	(revision 13810)
+++ trunk/psModules/src/detrend/pmBias.c	(revision 13920)
@@ -17,4 +17,7 @@
 #include "pmBias.h"
 
+#define SMOOTH_NSIGMA 4.0               // Number of Gaussian sigma the smoothing kernel extends
+
+
 static void overscanOptionsFree(pmOverscanOptions *options)
 {
@@ -24,5 +27,6 @@
 }
 
-pmOverscanOptions *pmOverscanOptionsAlloc(bool single, pmFit fitType, unsigned int order, psStats *stat)
+pmOverscanOptions *pmOverscanOptionsAlloc(bool single, pmFit fitType, unsigned int order, psStats *stat,
+                                          int boxcar, float gauss)
 {
     pmOverscanOptions *opts = psAlloc(sizeof(pmOverscanOptions));
@@ -34,4 +38,8 @@
     opts->order = order;
     opts->stat = psMemIncrRefCounter(stat);
+
+    // Smoothing
+    opts->boxcar = boxcar;
+    opts->gauss = gauss;
 
     // Outputs
@@ -151,4 +159,19 @@
             mask->data.U8[i] = 1;
         }
+    }
+
+    // Smooth the reduced vector
+    if (overscanOpts->boxcar > 0) {
+        psVector *smoothed = psVectorBoxcar(NULL, reduced, overscanOpts->boxcar); // Smoothed vector
+        psFree(reduced);
+        reduced = smoothed;
+    }
+    if (isfinite(overscanOpts->gauss) && overscanOpts->gauss > 0) {
+        if (overscanOpts->boxcar > 0) {
+            psWarning("Gaussian smoothing the boxcar smoothed overscan --- you asked for it.");
+        }
+        psVector *smoothed = psVectorSmooth(NULL, reduced, overscanOpts->gauss, SMOOTH_NSIGMA);
+        psFree(reduced);
+        reduced = smoothed;
     }