Example usage for org.apache.commons.math3.transform FastFourierTransformer transform

Introduction

In this page you can find the example usage for org.apache.commons.math3.transform FastFourierTransformer transform.

Prototype

public Complex[] transform(final Complex[] f, final TransformType type) 

Source Link

Document

Returns the (forward, inverse) transform of the specified complex data set.

Usage

From source file:com.mycompany.semconsolewebapp.FFT.java

public static double[] forward(double[] data) {
    FastFourierTransformer f = new FastFourierTransformer(DftNormalization.STANDARD);
    Complex[] fftC = f.transform(data, TransformType.FORWARD);

    for (int i = 0; i < data.length; i++) {

        data[i] = fftC[i].abs();// ww w. ja  v  a  2  s .  c om

        if (Double.isNaN(data[i])) {
            System.out.println("C " + fftC[i].getReal() + " + i" + fftC[i].getImaginary());
            System.out.println("D " + data[i]);
            break;
        }
    }

    return data;
}

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From source file:com.bleedobsidian.datawave.utils.Sinewave.java

/**
 * Calculate the frequency of sine wave from sound data.
 * //www .  j  a  va 2s .c  o  m
 * @param sampleRate Sample rate.
 * @param samples Samples.
 * 
 * @return Frequency.
 */
public static double calculateFrequency(double sampleRate, double[] samples) {
    FastFourierTransformer transformer = new FastFourierTransformer(DftNormalization.STANDARD);
    Complex[] complex = transformer.transform(samples, TransformType.FORWARD);

    double real;
    double im;
    double mag[] = new double[complex.length];

    for (int i = 0; i < complex.length; i++) {
        real = complex[i].getReal();
        im = complex[i].getImaginary();
        mag[i] = Math.sqrt((real * real) + (im * im));
    }

    double peak = 0.2;
    int index = -1;
    for (int i = 0; i < complex.length; i++) {
        if (peak < mag[i]) {
            index = i;
            peak = mag[i];
        }
    }

    return ((sampleRate * index) / Audio.SAMPLE_BUFFER_SIZE) * 2;
}

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From source file:com.fpuna.preproceso.util.Util.java

public static double[] transform(double[] input) {
    //double[] tempConversion = new double[input.length];
    double[] tempConversion = new double[2048];

    FastFourierTransformer transformer = new FastFourierTransformer(DftNormalization.STANDARD);
    try {//from   w ww . j a v a 2 s  . com
        Complex[] complx = transformer.transform(input, TransformType.FORWARD);

        for (int i = 0; i < complx.length; i++) {
            double rr = (complx[i].getReal());
            double ri = (complx[i].getImaginary());

            tempConversion[i] = Math.sqrt((rr * rr) + (ri * ri));
        }

    } catch (IllegalArgumentException e) {
        System.out.println(e);
    }

    return tempConversion;
}

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From source file:br.prof.salesfilho.oci.util.OCIUtils.java

public static Complex[] fft(double[] input, TransformType type) {
    FastFourierTransformer fft = new FastFourierTransformer(DftNormalization.STANDARD);
    Complex[] resultComplex = fft.transform(input, type);
    return resultComplex;
}

---

From source file:br.prof.salesfilho.oci.util.OCIUtils.java

public static Complex[] fft(Complex[] input, TransformType type) {
    FastFourierTransformer fft = new FastFourierTransformer(DftNormalization.STANDARD);
    Complex[] resultComplex = fft.transform(input, type);
    return resultComplex;
}

---

From source file:br.prof.salesfilho.oci.util.OCIUtils.java

public static double[] fft_forward_double(double[] input) {
    FastFourierTransformer fft = new FastFourierTransformer(DftNormalization.STANDARD);
    Complex[] complexTransInput = fft.transform(input, TransformType.FORWARD);
    double[] result = new double[complexTransInput.length];
    for (int i = 0; i < complexTransInput.length; i++) {
        result[i] = (complexTransInput[i].getReal());
    }//www .  j a v a2  s . co m
    return result;
}

---

From source file:br.prof.salesfilho.oci.util.OCIUtils.java

public static double[] fft_magnitude(double[] input) {
    FastFourierTransformer fft = new FastFourierTransformer(DftNormalization.STANDARD);
    Complex[] complexTransInput = fft.transform(input, TransformType.FORWARD);
    for (int i = 0; i < complexTransInput.length; i++) {
        double real = (complexTransInput[i].getReal());
        double img = (complexTransInput[i].getImaginary());
        input[i] = (Math.pow(real, 2) + Math.pow(img, 2));
    }/*from   w w  w  .  j  a v a 2  s  .  co  m*/
    return input;
}

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From source file:net.sf.dsp4j.octave.packages.signal_1_0_11.Freqz.java

public Freqz(double[] b, int n) {
    FastFourierTransformer fft = new FastFourierTransformer(DftNormalization.STANDARD);
    Complex[] hb = fft.transform(Arrays.copyOf(b, 2 * n), TransformType.FORWARD);

    H = Arrays.copyOfRange(hb, 0, n);
    w = new double[n];

    for (int i = 0; i < H.length; i++) {
        w[i] = Math.PI / n * i;//from   ww  w  .  j a  v a  2 s . com
    }
}

---

From source file:net.sf.dsp4j.octave.packages.signal_1_0_11.Freqz.java

public Freqz(double[] b, double[] a, int n) {
    FastFourierTransformer fft = new FastFourierTransformer(DftNormalization.STANDARD);

    Complex[] hb = fft.transform(Arrays.copyOf(b, 2 * n), TransformType.FORWARD);
    Complex[] ha = fft.transform(Arrays.copyOf(a, 2 * n), TransformType.FORWARD);

    H = new Complex[n];
    w = new double[n];

    for (int i = 0; i < H.length; i++) {
        H[i] = hb[i].divide(ha[i]);//  w w w  . jav a 2 s. co m
        w[i] = Math.PI / n * i;
    }

}

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From source file:br.prof.salesfilho.oci.service.ImageDescriptorService.java

/**
 * @param signal/*  w w  w  . ja v  a 2  s . c om*/
 * @param channel RGB and grayscale (1 = RED, 2 = GREEN, 3 = BLUE and 4 =
 * GRAYSCALE, diferent value GRAYSCALE is returned)
 * @return array of abs FFT
 */
public double[] fft(double[] signal, int channel) {
    double[] result = new double[signal.length];

    FastFourierTransformer fft = new FastFourierTransformer(DftNormalization.STANDARD);
    Complex[] complexTransInput = fft.transform(signal, TransformType.FORWARD);
    for (int i = 0; i < complexTransInput.length; i++) {
        result[i] = complexTransInput[i].getReal() + complexTransInput[i].getImaginary();
    }
    return result;
}

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