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authorPhil Burk <[email protected]>2015-04-29 08:15:04 -0700
committerPhil Burk <[email protected]>2015-04-29 08:15:04 -0700
commit3c25b6415d4a6fa3d719815c45ad6e98de57d744 (patch)
tree8029f57340ef5211586ea21d8a63614cfb1a9ae9 /src
parentd3c74876db36598813068ce0bb8ea887e41a1c71 (diff)
parent7aec269a333d43cc226a0c9c30986e4b50bafa28 (diff)
Merge pull request #5 from philburk/examples
Use AudioMath for pitch to frequency conversion. Cleanup PitchDetector.
Diffstat (limited to 'src')
-rw-r--r--src/com/jsyn/instruments/SubtractiveSynthVoice.java3
-rw-r--r--src/com/jsyn/unitgen/PitchDetector.java2
-rw-r--r--src/com/jsyn/util/AutoCorrelator.java42
3 files changed, 6 insertions, 41 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