Use AudioMath for pitch to frequency conversion.

Fix ListDevices default.
Cleanup interpolator in AutoCorrelator.
Remove empty string from SubtractiveSynth library.

6 files changed, 56 insertions, 57 deletions

diff --git a/src/com/jsyn/instruments/SubtractiveSynthVoice.java b/src/com/jsyn/instruments/SubtractiveSynthVoice.java
index 9ea593e..af3329e 100644
--- a/src/com/jsyn/instruments/SubtractiveSynthVoice.java
+++ b/src/com/jsyn/instruments/SubtractiveSynthVoice.java
@@ -135,6 +135,7 @@ public class SubtractiveSynthVoice extends Circuit implements UnitVoice {
                 cutoffRange.set(500.0);
                 filter.Q.set(3.0);
                 break;
+            case 2:
             default:
                 ampEnv.attack.set(0.1);
                 ampEnv.decay.set(0.3);
@@ -147,7 +148,7 @@ public class SubtractiveSynthVoice extends Circuit implements UnitVoice {
     }
 
     static String[] presetNames = {
-            "FastSaw", "SlowSaw", "BrightSaw", ""
+            "FastSaw", "SlowSaw", "BrightSaw"
     };
 
     static class MyVoiceDescription extends VoiceDescription {
diff --git a/src/com/jsyn/unitgen/PitchDetector.java b/src/com/jsyn/unitgen/PitchDetector.java
index 59bba69..da6a0e3 100644
--- a/src/com/jsyn/unitgen/PitchDetector.java
+++ b/src/com/jsyn/unitgen/PitchDetector.java
@@ -42,7 +42,7 @@ public class PitchDetector extends UnitGenerator {
     protected SignalCorrelator signalCorrelator;
 
     private double lastFrequency = 440.0;
-    private double lastPeriod = 44100.0 / lastFrequency; // result of analysis
+    private double lastPeriod = 44100.0 / lastFrequency; // result of analysis TODO update for 48000
     private double lastConfidence = 0.0; // Measure of confidence in the result.
 
     private static final int LOWEST_FREQUENCY = 40;
diff --git a/src/com/jsyn/util/AutoCorrelator.java b/src/com/jsyn/util/AutoCorrelator.java
index 5512abb..2996036 100644
--- a/src/com/jsyn/util/AutoCorrelator.java
+++ b/src/com/jsyn/util/AutoCorrelator.java
@@ -193,42 +193,9 @@ public class AutoCorrelator implements SignalCorrelator {
         return interpolatePeak(d1, d2, d3) + indexMax;
     }
 
-    // return offset between -1.0 and +1.0 from center
+    // Use quadratic fit to return offset between -0.5 and +0.5 from center.
     protected static double interpolatePeak(double d1, double d2, double d3) {
-        // System.out.println( "      d1 = " + d1 + ", d2 = " + d2 + ", d3 = "
-        // + d3 );
-        // Make sure d2 is a maximum or result will blow up.
-        if (d1 > d2)
-            return -1.0;
-        else if (d3 > d2)
-            return 1.0;
-
-        // The interpolated maximum should be the same
-        // point where the line between slopes crosses zero.
-        double y2 = d3 - d2;
-        double y1 = d2 - d1;
-        // System.out.println("      y1 = " + y1 + ", y2 = " + y2 );
-        // Derive equations for interpolated maximum.
-        // y = ax + b
-        // when y is zero, x = -b/a
-        // y2 = a*x2 + b
-        // y1 = a*x1 + b
-        // b = y2-a*x2
-        // y1 = a*x1 + (y2 - a*x2)
-        // y1 - y2 = a*(x1 - x2) ; x1 and x2 are one from each other
-        // y1 - y2 = a*(-1)
-        // a = y2 - y1
-        // for zero crossing:
-        // 0 = ax+b
-        // -ax = b
-        // x = -b / a
-        // = -(y2-a*x2)/a
-        // = (a*x2 -y2)/a
-        // = x2 - y2/a
-        // = x2 - (y2/(y2-y1))
-        double x2 = 0.5;
-        double precise = x2 - (y2 / (y2 - y1));
-        return precise;
+        return 0.5 * (d1 - d3) / (d1 - (2.0 * d2) + d3);
     }
 
     // Calculate a little more for each sample.
@@ -293,7 +260,6 @@ public class AutoCorrelator implements SignalCorrelator {
 
     @Override
     public boolean addSample(double value) {
-        boolean updated = false;
         double average = (value + previousSample) * 0.5;
         previousSample = value;
 
@@ -304,9 +270,7 @@ public class AutoCorrelator implements SignalCorrelator {
         }
         buffer[cursor] = (float) average;
 
-        updated = incrementalAnalysis();
-
-        return updated;
+        return incrementalAnalysis();
     }
 
     @Override
diff --git a/tests/com/jsyn/benchmarks/BenchJSyn.java b/tests/com/jsyn/benchmarks/BenchJSyn.java
index 51e09a4..5b8d128 100644
--- a/tests/com/jsyn/benchmarks/BenchJSyn.java
+++ b/tests/com/jsyn/benchmarks/BenchJSyn.java
@@ -22,9 +22,13 @@ package com.jsyn.benchmarks;
 import com.jsyn.JSyn;
 import com.jsyn.Synthesizer;
 import com.jsyn.unitgen.PassThrough;
+import com.jsyn.unitgen.PitchDetector;
 import com.jsyn.unitgen.SawtoothOscillator;
 import com.jsyn.unitgen.SawtoothOscillatorBL;
 import com.jsyn.unitgen.SawtoothOscillatorDPW;
+import com.jsyn.unitgen.SineOscillator;
+import com.jsyn.unitgen.SquareOscillator;
+import com.jsyn.unitgen.SquareOscillatorBL;
 import com.jsyn.unitgen.UnitOscillator;
 import com.softsynth.math.FourierMath;
 
@@ -57,11 +61,18 @@ public class BenchJSyn {
         double realTime = 10.0;
         int count = 40;
 
-        benchFFTDouble();
-        benchFFTFloat();
-        benchmarkOscillator(SawtoothOscillator.class, count, realTime);
-        benchmarkOscillator(SawtoothOscillatorDPW.class, count, realTime);
-        benchmarkOscillator(SawtoothOscillatorBL.class, count, realTime);
+        // benchFFTDouble();
+        // benchFFTFloat();
+        /*
+         * realTime = 20.0; benchmarkOscillator(SawtoothOscillator.class, count, realTime);
+         * benchmarkOscillator(SawtoothOscillatorDPW.class, count, realTime);
+         * benchmarkOscillator(SawtoothOscillatorBL.class, count, realTime);
+         */
+        benchmarkOscillator(SquareOscillator.class, count, realTime);
+        benchmarkOscillator(SquareOscillatorBL.class, count, realTime);
+
+        benchmarkOscillator(SineOscillator.class, count, realTime);
+        benchmarkPitchDetector(count, realTime);
 
     }
 
@@ -164,6 +175,37 @@ public class BenchJSyn {
         stopSynth();
     }
 
+    private void benchmarkPitchDetector(int count, double realTime) throws InstantiationException,
+            IllegalAccessException, InterruptedException {
+        startSynth();
+
+        PitchDetector detector = new PitchDetector();
+        synth.add(detector);
+        double frequency = 198.0;
+        double period = synth.getFrameRate() / frequency;
+        // simple harmonic synthesis
+        for (int i = 0; i < count; i++) {
+            SineOscillator osc = new SineOscillator();
+            synth.add(osc);
+            osc.frequency.set(frequency * (i + 1));
+            osc.amplitude.set(0.5 * (1.0 - (i * 0.2)));
+            osc.output.connect(detector.input);
+        }
+        detector.start();
+        startTiming();
+        synth.sleepFor(realTime);
+        endTiming(PitchDetector.class, count, realTime);
+
+        double measuredPeriod = detector.period.getValue();
+        double confidence = detector.confidence.getValue();
+        System.out.println("period = " + period + ", measured = " + measuredPeriod
+                + ", confidence = " + confidence);
+        if (confidence > 0.1) {
+            assert (Math.abs(measuredPeriod - period) < 0.1);
+        }
+        stopSynth();
+    }
+
     private void endTiming(Class<?> clazz, int count, double realTime) {
         endTime = System.nanoTime();
         double elapsedTime = (endTime - startTime) * 1E-9;
diff --git a/tests/com/jsyn/examples/ListAudioDevices.java b/tests/com/jsyn/examples/ListAudioDevices.java
index 6c5372d..dceaa0d 100644
--- a/tests/com/jsyn/examples/ListAudioDevices.java
+++ b/tests/com/jsyn/examples/ListAudioDevices.java
@@ -33,7 +33,7 @@ public class ListAudioDevices {
             int maxInputs = audioManager.getMaxInputChannels(i);
             int maxOutputs = audioManager.getMaxInputChannels(i);
             boolean isDefaultInput = (i == audioManager.getDefaultInputDeviceID());
-            boolean isDefaultOutput = (i == audioManager.getDefaultInputDeviceID());
+            boolean isDefaultOutput = (i == audioManager.getDefaultOutputDeviceID());
             System.out.println("#" + i + " : " + deviceName);
             System.out.println("  max inputs : " + maxInputs
                     + (isDefaultInput ? "   (default)" : ""));
diff --git a/tests/com/jsyn/examples/PlayChords.java b/tests/com/jsyn/examples/PlayChords.java
index 0b1ae2e..28cab5f 100644
--- a/tests/com/jsyn/examples/PlayChords.java
+++ b/tests/com/jsyn/examples/PlayChords.java
@@ -22,6 +22,7 @@ import com.jsyn.instruments.SubtractiveSynthVoice;
 import com.jsyn.unitgen.LineOut;
 import com.jsyn.unitgen.UnitVoice;
 import com.jsyn.util.VoiceAllocator;
+import com.softsynth.math.AudioMath;
 import com.softsynth.shared.time.TimeStamp;
 
 /**
@@ -167,21 +168,12 @@ public class PlayChords {
     }
 
     private void noteOn(double time, int noteNumber) {
-        double frequency = convertPitchToFrequency(noteNumber);
+        double frequency = AudioMath.pitchToFrequency(noteNumber);
         double amplitude = 0.2;
         TimeStamp timeStamp = new TimeStamp(time);
         allocator.noteOn(noteNumber, frequency, amplitude, timeStamp);
     }
 
-    /**
-     * Calculate frequency in Hertz based on MIDI pitch. Middle C is 60.0. You can use fractional
-     * pitches so 60.5 would give you a pitch half way between C and C#.
-     */
-    double convertPitchToFrequency(double pitch) {
-        final double concertA = 440.0;
-        return concertA * Math.pow(2.0, ((pitch - 69) * (1.0 / 12.0)));
-    }
-
     public static void main(String[] args) {
         new PlayChords().test();
     }