Changeset 34150

Timestamp:

Jul 13, 2012, 3:48:48 PM (14 years ago)

Author:

watersc1

Message:

Keep image average weights for pixel combination procedure, but switch
the variance combination to use a geometric mean of the input
variances. This prevents excessive variance regions from dominating
the output combined variance image.

File:

• trunk/psModules/src/imcombine/pmStack.c (modified) (2 diffs)

trunk/psModules/src/imcombine/pmStack.c

@@ -357 +357 @@
         sumWeight += weights->data.F32[i];
         if (variances) {
-            sumVarianceWeight += variances->data.F32[i] * PS_SQR(weights->data.F32[i]);
+          //            sumVarianceWeight += variances->data.F32[i] * PS_SQR(weights->data.F32[i]);
+          sumVarianceWeight += 1 / variances->data.F32[i];
         }
         if (exps) {
@@ -372 +373 @@
     *mean = sumValueWeight / sumWeight;
     if (var) {
-        *var = sumVarianceWeight / PS_SQR(sumWeight);
+      //*var = sumVarianceWeight / PS_SQR(sumWeight);
+      *var = 1 / sumVarianceWeight;
     }
     if (exp) {