unbroke face recognition

Josh Klontz
1 parent eecc7b41
Showing 3 changed files with 66 additions and 4 deletions
sdk/plugins/algorithms.cpp
sdk/plugins/compare.cpp
sdk/plugins/quality.cpp
@@ -70,6 +70,7 @@ class AlgorithmsInitializer : public Initializer
         Globals->abbreviations.insert("FaceClassificationExtraction", "((Grid(7,7)+SIFTDescriptor(8)+ByRow)/DenseLBP+PCA(0.95,instances=-1)+Cat)");
         Globals->abbreviations.insert("AgeRegressor", "Center(Range,instances=-1)+SVM(RBF,EPS_SVR,instances=100)");
         Globals->abbreviations.insert("GenderClassifier", "Center(Range,instances=-1)+SVM(RBF,C_SVC,instances=4000)");
+        Globals->abbreviations.insert("UCharL1", "Unit(ByteL1)");
     }
 };
  
@@ -119,7 +119,7 @@ BR_REGISTER(Distance, DistDistance)
  * \brief Fast 8-bit L1 distance
  * \author Josh Klontz \cite jklontz
  */
-class UCharL1Distance : public Distance
+class ByteL1Distance : public Distance
 {
     Q_OBJECT
  
@@ -129,7 +129,7 @@ class UCharL1Distance : public Distance
     }
 };
  
-BR_REGISTER(Distance, UCharL1Distance)
+BR_REGISTER(Distance, ByteL1Distance)
  
  
 /*!
@@ -137,7 +137,7 @@ BR_REGISTER(Distance, UCharL1Distance)
  * \brief Fast 4-bit L1 distance
  * \author Josh Klontz \cite jklontz
  */
-class PackedUCharL1Distance : public Distance
+class HalfByteL1Distance : public Distance
 {
     Q_OBJECT
  
@@ -147,7 +147,7 @@ class PackedUCharL1Distance : public Distance
     }
 };
  
-BR_REGISTER(Distance, PackedUCharL1Distance)
+BR_REGISTER(Distance, HalfByteL1Distance)
  
 /*!
  * \ingroup distances
@@ -201,6 +201,67 @@ class MPDistance : public Distance
  
 BR_REGISTER(Distance, MPDistance)
  
+/*!
+ * \ingroup distances
+ * \brief Linear normalizes of a distance so the mean impostor score is 0 and the mean genuine score is 1.
+ * \author Josh Klontz \cite jklontz
+ */
+class UnitDistance : public Distance
+{
+    Q_OBJECT
+    Q_PROPERTY(br::Distance *distance READ get_distance WRITE set_distance RESET reset_distance)
+    Q_PROPERTY(float a READ get_a WRITE set_a RESET reset_a)
+    Q_PROPERTY(float b READ get_b WRITE set_b RESET reset_b)
+    BR_PROPERTY(br::Distance*, distance, make("Dist(L2)"))
+    BR_PROPERTY(float, a, 1)
+    BR_PROPERTY(float, b, 0)
+
+    void train(const TemplateList &templates)
+    {
+        const TemplateList samples = templates.mid(0, 2000);
+        const QList<float> sampleLabels = samples.labels<float>();
+        QScopedPointer<MatrixOutput> memoryOutput(dynamic_cast<MatrixOutput*>(Output::make(".Matrix", FileList(samples.size()), FileList(samples.size()))));
+        compare(samples, samples, memoryOutput.data());
+
+        double genuineAccumulator, impostorAccumulator;
+        int genuineCount, impostorCount;
+        genuineAccumulator = impostorAccumulator = genuineCount = impostorCount = 0;
+
+        for (int i=0; i<samples.size(); i++) {
+            for (int j=0; j<i; j++) {
+                const float val = memoryOutput.data()->data.at<float>(i, j);
+                if (sampleLabels[i] == sampleLabels[j]) {
+                    genuineAccumulator += val;
+                    genuineCount++;
+                } else {
+                    impostorAccumulator += val;
+                    impostorCount++;
+                }
+            }
+        }
+
+        if (genuineCount == 0) { qWarning("No genuine matches."); return; }
+        if (impostorCount == 0) { qWarning("No impostor matches."); return; }
+
+        double genuineMean = genuineAccumulator / genuineCount;
+        double impostorMean = impostorAccumulator / impostorCount;
+
+        if (genuineMean == impostorMean) { qWarning("Genuines and impostors are indistinguishable."); return; }
+
+        a = 1.0/(genuineMean-impostorMean);
+        b = impostorMean;
+
+        qDebug("a = %f, b = %f", a, b);
+    }
+
+    float _compare(const Template &target, const Template &query) const
+    {
+        return a * (distance->compare(target, query) - b);
+    }
+};
+
+BR_REGISTER(Distance, UnitDistance)
+
 } // namespace br
  
 #include "quality.moc"