1 files changed, 13 insertions, 2 deletions
diff --git a/apps/OboeTester/app/src/main/cpp/analyzer/DataPathAnalyzer.h b/apps/OboeTester/app/src/main/cpp/analyzer/DataPathAnalyzer.h
index 5814dccd..953cf49a 100644
--- a/apps/OboeTester/app/src/main/cpp/analyzer/DataPathAnalyzer.h
+++ b/apps/OboeTester/app/src/main/cpp/analyzer/DataPathAnalyzer.h
@@ -41,6 +41,18 @@ public:
         setNoiseAmplitude(0.02);
     }
 
+    double calculatePhaseError(double p1, double p2) {
+        double diff = p1 - p2;
+        // Wrap around the circle.
+        while (diff > M_PI) {
+            diff -= (2 * M_PI);
+        }
+        while (diff < -M_PI) {
+            diff += (2 * M_PI);
+        }
+        return diff;
+    }
+
     /**
      * @param frameData contains microphone data with sine signal feedback
      * @param channelCount
@@ -52,9 +64,8 @@ public:
         mInfiniteRecording.write(sample);
 
         if (transformSample(sample, mOutputPhase)) {
-            resetAccumulator();
             // Analyze magnitude and phase on every period.
-            double diff = abs(mPhaseOffset - mPreviousPhaseOffset);
+            double diff = fabs(calculatePhaseError(mPhaseOffset, mPreviousPhaseOffset));
             if (diff < mPhaseTolerance) {
                 mMaxMagnitude = std::max(mMagnitude, mMaxMagnitude);
             }