Index: trunk/psLib/src/imageops/psImageInterpolate.c
===================================================================
--- trunk/psLib/src/imageops/psImageInterpolate.c	(revision 23229)
+++ trunk/psLib/src/imageops/psImageInterpolate.c	(revision 23231)
@@ -133,7 +133,7 @@
     }
 
-    float norm1 = 2.0 / PS_SQR(M_PI); // Normalisation for laczos
-    float norm2 = M_PI * 4.0 / (float)size; // Normalisation for sinc function 1
-    float norm3 = M_PI_2 * 4.0 / (float)size; // Normalisation for sinc function 2
+    float norm1 = size / 2.0 / PS_SQR(M_PI); // Normalisation for laczos
+    float norm2 = M_PI;                 // Normalisation for sinc function 1
+    float norm3 = M_PI * 2.0 / (float)size; // Normalisation for sinc function 2
     float pos = - (size - 1)/2 - frac;  // Position of interest
     for (int i = 0; i < size; i++, pos += 1.0) {