From eefa02a86d6950bf611414f88169a3cc057029a3 Mon Sep 17 00:00:00 2001 From: James Ball Date: Sun, 13 Nov 2022 12:19:43 +0000 Subject: [PATCH] Go back to using FFT rather than tarsos DSP --- pom.xml | 8 +- .../java/sh/ball/audio/FrequencyAnalyser.java | 43 +- src/main/java/sh/ball/math/fft/FFT.java | 894 ++++++++++++++++++ 3 files changed, 929 insertions(+), 16 deletions(-) create mode 100644 src/main/java/sh/ball/math/fft/FFT.java diff --git a/pom.xml b/pom.xml index 1dd37fb..189db7f 100644 --- a/pom.xml +++ b/pom.xml @@ -179,7 +179,7 @@ com.google.code.gson gson - 2.9.0 + 2.10 org.java-websocket @@ -189,12 +189,12 @@ org.slf4j slf4j-api - 1.7.36 + 2.0.3 org.slf4j slf4j-simple - 1.7.36 + 2.0.3 org.luaj @@ -205,7 +205,7 @@ org.apache.bcel bcel - 6.5.0 + 6.6.0 diff --git a/src/main/java/sh/ball/audio/FrequencyAnalyser.java b/src/main/java/sh/ball/audio/FrequencyAnalyser.java index de40898..3384d89 100644 --- a/src/main/java/sh/ball/audio/FrequencyAnalyser.java +++ b/src/main/java/sh/ball/audio/FrequencyAnalyser.java @@ -1,8 +1,6 @@ package sh.ball.audio; -import be.tarsos.dsp.pitch.DynamicWavelet; -import be.tarsos.dsp.pitch.PitchDetectionResult; -import be.tarsos.dsp.pitch.PitchDetector; +import sh.ball.math.fft.FFT; import java.util.ArrayList; import java.util.List; @@ -14,7 +12,7 @@ public class FrequencyAnalyser implements Runnable { private static final int DEFAULT_SAMPLE_RATE = 192000; // increase this for higher frequency resolution, but less frequent frequency calculation - private static final int DEFAULT_POWER_OF_TWO = 15; + private static final int DEFAULT_POWER_OF_TWO = 18; private final AudioPlayer audioPlayer; private final List listeners = new ArrayList<>(); @@ -43,9 +41,6 @@ public class FrequencyAnalyser implements Runnable { @Override public void run() { double[] buf = new double[2 << (powerOfTwo - 1)]; - float[] leftSamples = new float[buf.length / 2]; - float[] rightSamples = new float[buf.length / 2]; - PitchDetector pitchDetector = new DynamicWavelet(sampleRate, buf.length / 2); while (!stopped) { try { @@ -53,15 +48,39 @@ public class FrequencyAnalyser implements Runnable { } catch (InterruptedException e) { logger.log(Level.SEVERE, e.getMessage(), e); } + double[] leftSamples = new double[buf.length / 2]; + double[] rightSamples = new double[buf.length / 2]; for (int i = 0; i < buf.length; i += 2) { - leftSamples[i / 2] = (float) buf[i]; - rightSamples[i / 2] = (float) buf[i + 1]; + leftSamples[i / 2] = buf[i]; + rightSamples[i / 2] = buf[i + 1]; } - PitchDetectionResult leftFrequency = pitchDetector.getPitch(leftSamples); - PitchDetectionResult rightFrequency = pitchDetector.getPitch(rightSamples); + FFT leftFft = new FFT(leftSamples, null, false, true); + FFT rightFft = new FFT(rightSamples, null, false, true); - notifyListeners(leftFrequency.getPitch(), rightFrequency.getPitch()); + double[] leftMags = leftFft.getMagnitudeSpectrum(); + double[] rightMags = rightFft.getMagnitudeSpectrum(); + double[] bins = leftFft.getBinLabels(sampleRate); + + int maxLeftIndex = 0; + double maxLeft = Double.NEGATIVE_INFINITY; + int maxRightIndex = 0; + double maxRight = Double.NEGATIVE_INFINITY; + for (int i = 0; i < leftMags.length; i++) { + if (bins[i] < 20 || bins[i] > 20000) { + continue; + } + if (leftMags[i] > maxLeft) { + maxLeftIndex = i; + maxLeft = leftMags[i]; + } + if (rightMags[i] > maxRight) { + maxRightIndex = i; + maxRight = rightMags[i]; + } + } + + notifyListeners(bins[maxLeftIndex], bins[maxRightIndex]); } } diff --git a/src/main/java/sh/ball/math/fft/FFT.java b/src/main/java/sh/ball/math/fft/FFT.java new file mode 100644 index 0000000..59d2072 --- /dev/null +++ b/src/main/java/sh/ball/math/fft/FFT.java @@ -0,0 +1,894 @@ +/* + * @(#)FFT.java 1.0 April 5, 2005. + * + * Cory McKay + * McGill Univarsity + * + * https://sourceforge.net/p/jaudio/svn/2/tree/jAudio%201.0/src/jAudioFeatureExtractor/jAudioTools/FFT.java + * + + LICENSE copied from https://github.com/dmcennis/jAudioGIT/blob/master/License.txt + + GNU LESSER GENERAL PUBLIC LICENSE + Version 2.1, February 1999 + + Copyright (C) 1991, 1999 Free Software Foundation, Inc. + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + +(This is the first released version of the Lesser GPL. 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See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, write to the Free Software + Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 + USA + +Daniel McEnnis: maintainer +dmcennis@gmail.com +160 Johnson St +Marion OH 43302 + */ + +package sh.ball.math.fft; + + +/** + * This class performs a complex to complex Fast Fourier Transform. Forward and inverse + * transforms may both be performed. The transforms may be performed with or without + * the application of a Hanning window. + * + *

The FFT is performed by this class' constructor. The real and imaginary results + * are both stored, and the magnitude spectrum, power spectrum and phase angles may + * also be accessed (along with appropriate frequency bin labels for the magnitude + * and power spectra). + * + * @author Cory McKay + */ +public class FFT +{ + /* FIELDS ******************************************************************/ + + + // The results of the FFT. + private double[] real_output; + private double[] imaginary_output; + + // The phase angles + private double[] output_angle; + + // Magnitude and power spectra + private double[] output_magnitude; + private double[] output_power; + + + /* CONSTRUCTOR *************************************************************/ + + + /** + * Performs the Fourier transform and stores the real and imaginary results. + * Input signals are zero-padded if they do not have a length equal to a + * power of 2. + * + * @param real_input The real part of the signal to be transformed. + * @param imaginary_input The imaginary part of the signal to be. + * transformed. This may be null if the signal + * is entirely real. + * @param inverse_transform A value of false implies that a forward + * transform is to be applied, and a value of + * true means that an inverse transform is tob + * be applied. + * @param use_hanning_window A value of true means that a Hanning window + * will be applied to the real_input. A value + * of valse will result in the application of + * a Hanning window. + * @throws Exception Throws an exception if the real and imaginary + * inputs are of different sizes or if less than + * three input samples are provided. + */ + public FFT( double[] real_input, + double[] imaginary_input, + boolean inverse_transform, + boolean use_hanning_window ) { + // Throw an exception if non-matching input signals are provided + if (imaginary_input != null) + if (real_input.length != imaginary_input.length) + throw new RuntimeException("Imaginary and real inputs are of different sizes."); + + // Throw an exception if less than three samples are provided + if (real_input.length < 3) + throw new RuntimeException( "Only " + real_input.length + " samples provided.\n" + + "At least three are needed." ); + + // Verify that the input size has a number of samples that is a + // power of 2. If not, then increase the size of the array using + // zero-padding. Also creates a zero filled imaginary component + // of the input if none was specified. + int valid_size = ensureIsPowerOfN(real_input.length, 2); + if (valid_size != real_input.length) + { + double[] temp = new double[valid_size]; + for (int i = 0; i < real_input.length; i++) + temp[i] = real_input[i]; + for (int i = real_input.length; i < valid_size; i++) + temp[i] = 0.0; + real_input = temp; + + if (imaginary_input == null) + { + imaginary_input = new double[valid_size]; + for (int i = 0; i < imaginary_input.length; i++) + imaginary_input[i] = 0.0; + } + else + { + temp = new double[valid_size]; + for (int i = 0; i < imaginary_input.length; i++) + temp[i] = imaginary_input[i]; + for (int i = imaginary_input.length; i < valid_size; i++) + temp[i] = 0.0; + imaginary_input = temp; + } + } + else if (imaginary_input == null) + { + imaginary_input = new double[valid_size]; + for (int i = 0; i < imaginary_input.length; i++) + imaginary_input[i] = 0.0; + } + + // Instantiate the arrays to hold the output and copy the input + // to them, since the algorithm used here is self-processing + real_output = new double[valid_size]; + System.arraycopy(real_input, 0, real_output, 0, valid_size); + imaginary_output = new double[valid_size]; + System.arraycopy(imaginary_input, 0, imaginary_output, 0, valid_size); + + // Apply a Hanning window to the real values if this option is + // selected + if (use_hanning_window) + { + for (int i = 0; i < real_output.length; i++) + { + double hanning = 0.5 - 0.5 * Math.cos(2 * Math.PI * i / valid_size); + real_output[i] *= hanning; + } + } + + // Determine whether this is a forward or inverse transform + int forward_transform = 1; + if (inverse_transform) + forward_transform = -1; + + // Reorder the input data into reverse binary order + double scale = 1.0; + int j = 0; + for (int i = 0; i < valid_size; ++i) + { + if (j >= i) + { + double tempr = real_output[j] * scale; + double tempi = imaginary_output[j] * scale; + real_output[j] = real_output[i] * scale; + imaginary_output[j] = imaginary_output[i] * scale; + real_output[i] = tempr; + imaginary_output[i] = tempi; + } + int m = valid_size / 2; + while (m >= 1 && j >= m) + { + j -= m; + m /= 2; + } + j += m; + } + + // Perform the spectral recombination stage by stage + int stage = 0; + int max_spectra_for_stage; + int step_size; + for( max_spectra_for_stage = 1, step_size = 2 * max_spectra_for_stage; + max_spectra_for_stage < valid_size; + max_spectra_for_stage = step_size, step_size = 2 * max_spectra_for_stage) + { + double delta_angle = forward_transform * Math.PI / max_spectra_for_stage; + + // Loop once for each individual spectra + for (int spectra_count = 0; spectra_count < max_spectra_for_stage; ++spectra_count) + { + double angle = spectra_count * delta_angle; + double real_correction = Math.cos(angle); + double imag_correction = Math.sin(angle); + + int right = 0; + for (int left = spectra_count; left < valid_size; left += step_size) + { + right = left + max_spectra_for_stage; + double temp_real = real_correction * real_output[right] - + imag_correction * imaginary_output[right]; + double temp_imag = real_correction * imaginary_output[right] + + imag_correction * real_output[right]; + real_output[right] = real_output[left] - temp_real; + imaginary_output[right] = imaginary_output[left] - temp_imag; + real_output[left] += temp_real; + imaginary_output[left] += temp_imag; + } + } + max_spectra_for_stage = step_size; + } + + // Set the angle and magnitude to null originally + output_angle = null; + output_power = null; + output_magnitude = null; + } + + /* PUBLIC METHODS **********************************************************/ + + /** + * Returns the magnitudes spectrum. It only makes sense to call + * this method if this object was instantiated as a forward Fourier + * transform. + * + *

Only the left side of the spectrum is returned, as the folded + * portion of the spectrum is redundant for the purpose of the magnitude + * spectrum. This means that the bins only go up to half of the + * sampling rate. + * + * @return The magnitude of each frequency bin. + */ + public double[] getMagnitudeSpectrum() + { + // Only calculate the magnitudes if they have not yet been calculated + if (output_magnitude == null) + { + int number_unfolded_bins = imaginary_output.length / 2; + output_magnitude = new double[number_unfolded_bins]; + for(int i = 0; i < output_magnitude.length; i++) + output_magnitude[i] = ( Math.sqrt(real_output[i] * real_output[i] + imaginary_output[i] * imaginary_output[i]) ) / real_output.length; + } + + // Return the magnitudes + return output_magnitude; + } + + + /** + * Returns the power spectrum. It only makes sense to call + * this method if this object was instantiated as a forward Fourier + * transform. + * + *

Only the left side of the spectrum is returned, as the folded + * portion of the spectrum is redundant for the purpose of the power + * spectrum. This means that the bins only go up to half of the + * sampling rate. + * + * @return The magnitude of each frequency bin. + */ + public double[] getPowerSpectrum() + { + // Only calculate the powers if they have not yet been calculated + if (output_power == null) + { + int number_unfolded_bins = imaginary_output.length / 2; + output_power = new double[number_unfolded_bins]; + for(int i = 0; i < output_power.length; i++) + output_power[i] = (real_output[i] * real_output[i] + imaginary_output[i] * imaginary_output[i]) / real_output.length; + } + + // Return the power + return output_power; + } + + + /** + * Returns the phase angle for each frequency bin. It only makes sense to + * call this method if this object was instantiated as a forward Fourier + * transform. + * + *

Only the left side of the spectrum is returned, as the folded + * portion of the spectrum is redundant for the purpose of the phase + * angles. This means that the bins only go up to half of the + * sampling rate. + * + * @return The phase angle for each frequency bin in degrees. + */ + public double[] getPhaseAngles() + { + // Only calculate the angles if they have not yet been calculated + if (output_angle == null) + { + int number_unfolded_bins = imaginary_output.length / 2; + output_angle = new double[number_unfolded_bins]; + for(int i = 0; i < output_angle.length; i++) + { + if(imaginary_output[i] == 0.0 && real_output[i] == 0.0) + output_angle[i] = 0.0; + else + output_angle[i] = Math.atan(imaginary_output[i] / real_output[i]) * 180.0 / Math.PI; + + if(real_output[i] < 0.0 && imaginary_output[i] == 0.0) + output_angle[i] = 180.0; + else if(real_output[i] < 0.0 && imaginary_output[i] == -0.0) + output_angle[i] = -180.0; + else if(real_output[i] < 0.0 && imaginary_output[i] > 0.0) + output_angle[i] += 180.0; + else if(real_output[i] < 0.0 && imaginary_output[i] < 0.0) + output_angle[i] += -180.0; + } + } + + // Return the phase angles + return output_angle; + } + + + /** + * Returns the frequency bin labels for each bin referred to by the + * real values, imaginary values, magnitudes and phase angles as + * determined by the given sampling rate. + * + * @param sampling_rate The sampling rate that was used to perform + * the FFT. + * @return The bin labels. + */ + public double[] getBinLabels(double sampling_rate) + { + int number_bins = real_output.length; + double bin_width = sampling_rate / (double) number_bins; + int number_unfolded_bins = imaginary_output.length / 2; + double[] labels = new double[number_unfolded_bins]; + labels[0] = 0.0; + for (int bin = 1; bin < labels.length; bin++) + labels[bin] = bin * bin_width; + return labels; + } + + + /** + * Returns the real values as calculated by the FFT. + * + * @return The real values. + */ + public double[] getRealValues() + { + return real_output; + } + + + /** + * Returns the real values as calculated by the FFT. + * + * @return The real values. + */ + public double[] getImaginaryValues() + { + return imaginary_output; + } + + /* PRIVATE METHODS *********************************************************/ + + /** + * If the given x is a power of the given n, then x is returned. + * If not, then the next value above the given x that is a power + * of n is returned. + * + *

IMPORTANT: Both x and n must be greater than zero. + * + * @param x The value to ensure is a power of n. + * @param n The power to base x's validation on. + */ + private static int ensureIsPowerOfN(int x, int n) + { + double log_value = logBaseN((double) x, (double) n); + int log_int = (int) log_value; + int valid_size = pow(n, log_int); + if (valid_size != x) + valid_size = pow(n, log_int + 1); + return valid_size; + } + + /** + * Returns the logarithm of the specified base of the given number. + * + *

IMPORTANT: Both x and n must be greater than zero. + * + * @param x The value to find the log of. + * @param n The base of the logarithm. + */ + private static double logBaseN(double x, double n) + { + return (Math.log10(x) / Math.log10(n)); + } + + /** + * Returns the given a raised to the power of the given b. + * + *

IMPORTANT: b must be greater than zero. + * + * @param a The base. + * @param b The exponent. + */ + private static int pow(int a, int b) + { + int result = a; + for (int i = 1; i < b; i++) + result *= a; + return result; + } +} \ No newline at end of file