Changeset 695

Timestamp:

03/15/06 10:22:48 (18 years ago)

Author:

bittner

Message:

pvs homegenity measure added

Location:

GTP/trunk/Lib/Vis/Preprocessing/src

Files:

• Makefile (modified) (1 diff)
• Pvs.h (modified) (2 diffs)

GTP/trunk/Lib/Vis/Preprocessing/src/Makefile

@@ -1 +1 @@
 #############################################################################
 # Makefile for building: preprocessor
-# Generated by qmake (2.00a) (Qt 4.1.0) on: út 14. II 10:13:02 2006
+# Generated by qmake (2.00a) (Qt 4.1.0) on: st 15. III 09:41:58 2006
 # Project:  preprocessor.pro
 # Template: app

GTP/trunk/Lib/Vis/Preprocessing/src/Pvs.h

@@ -114 +114 @@
   
 
+  /** Compute continuous PVS difference */
+  float GetPvsHomogenity(const Pvs<T> &pvs) {
+        float 
+          pvsReduction,
+          pvsEnlargement;
+
+        ComputeContinuousPvsDifference(pvs,
+                                                                   pvsReduction,
+                                                                   pvsEnlargement);
+
+        return pvsReduction + pvsEnlargement;
+  }
+
                                           
                                           
@@ -122 +135 @@
 
 
-/** Compute continuous PVS difference */
+/**
+   Compute continuous PVS difference of 'b' with respect to the base PVS (*this).
+   Provides separatelly PVS reduction from PVS enlargement.
+
+*/
 template <typename T>
 void
-Pvs<T>::ComputeContinuousPvsDifference(const Pvs<T> &pvs,
+Pvs<T>::ComputeContinuousPvsDifference(const Pvs<T> &b,
                                                                            float &pvsReduction,
                                                                            float &pvsEnlargement)
 {
-  
-
+  // Uses sum of log differences, which corresponds to entropy
+  std::map<T, PvsData<T>, LtSample<T> >::const_iterator it;
+  
+  for (it = b.mEntries.begin(); it != b.mEntries.end(); ++ it) {
+        float bSumPdf = (*it).second.mSumPdf;
+        float aSumPdf = 0.0f;
+        PvsData<T> *data = Find((*it).first);           
+        if (data) {
+          aSumPdf = data->second.mSumPdf;
+          // mark this entry as processed to avoid double counting
+          data->second.mSumPdf = -aSumPdf;
+        }
+        float diff = bSumPdf - aSumPdf;
+        
+        if (diff > 0.0f) {
+          pvsEnlargement += diff;
+        } else {
+          pvsReduction += -diff;
+        }
+  }
+  
+  for (it = mEntries.begin(); it != mEntries.end(); ++ it) {
+        float aSumPdf = (*it).second.mSumPdf;
+        float bSumPdf = 0.0f;
+        if (aSumPdf < 0.0f) {
+          // this entry was already accounted for!
+          // just revert it back
+          (*it).second.mSumPdf = -aSumPdf;
+        } else {
+          PvsData<T> *data = b.Find((*it).first);
+          if (data) {
+                bSumPdf = data->second.mSumPdf;
+          }
+          float diff = bSumPdf - aSumPdf;
+          
+          if (diff > 0.0f) {
+                pvsEnlargement += diff;
+          } else {
+                pvsReduction += -diff;
+          }
+        }
+  }
 }