C++ (Cpp) FFTFrame::realData Examples

Example #1

File: FFTFrameGStreamer.cpp Project: SchleunigerAG/WinEC7_Qt5.3.1_Fixes

// Copy constructor.
FFTFrame::FFTFrame(const FFTFrame& frame)
    : m_FFTSize(frame.m_FFTSize)
    , m_log2FFTSize(frame.m_log2FFTSize)
    , m_realData(unpackedFFTDataSize(frame.m_FFTSize))
    , m_imagData(unpackedFFTDataSize(frame.m_FFTSize))
{
    m_complexData = WTF::fastNewArray<GstFFTF32Complex>(unpackedFFTDataSize(m_FFTSize));

    int fftLength = gst_fft_next_fast_length(m_FFTSize);
    m_fft = gst_fft_f32_new(fftLength, FALSE);
    m_inverseFft = gst_fft_f32_new(fftLength, TRUE);

    // Copy/setup frame data.
    memcpy(realData(), frame.realData(), sizeof(float) * unpackedFFTDataSize(m_FFTSize));
    memcpy(imagData(), frame.imagData(), sizeof(float) * unpackedFFTDataSize(m_FFTSize));
}

Example #2

File: FFTFrameFFMPEG.cpp Project: mirror/chromium

// Copy constructor.
FFTFrame::FFTFrame(const FFTFrame& frame)
    : m_FFTSize(frame.m_FFTSize),
      m_log2FFTSize(frame.m_log2FFTSize),
      m_realData(frame.m_FFTSize / 2),
      m_imagData(frame.m_FFTSize / 2),
      m_forwardContext(nullptr),
      m_inverseContext(nullptr),
      m_complexData(frame.m_FFTSize) {
  m_forwardContext = contextForSize(m_FFTSize, DFT_R2C);
  m_inverseContext = contextForSize(m_FFTSize, IDFT_C2R);

  // Copy/setup frame data.
  unsigned nbytes = sizeof(float) * (m_FFTSize / 2);
  memcpy(realData(), frame.realData(), nbytes);
  memcpy(imagData(), frame.imagData(), nbytes);
}

Example #3

File: FFTFrameFFTW.cpp Project: dankurka/webkit_titanium

// Copy constructor.
FFTFrame::FFTFrame(const FFTFrame& frame)
    : m_FFTSize(frame.m_FFTSize)
    , m_log2FFTSize(frame.m_log2FFTSize)
    , m_forwardPlan(0)
    , m_backwardPlan(0)
    , m_data(2 * (3 + unpackedFFTWDataSize(fftSize()))) // enough space for real and imaginary data plus 16-byte alignment padding
{
    // See the normal constructor for an explanation of the temporary pointer.
    float temporary;
    m_forwardPlan = fftwPlanForSize(m_FFTSize, Forward,
                                    &temporary, realData(), imagData());
    m_backwardPlan = fftwPlanForSize(m_FFTSize, Backward,
                                     realData(), imagData(), &temporary);

    // Copy/setup frame data.
    size_t nbytes = sizeof(float) * unpackedFFTWDataSize(fftSize());
    memcpy(realData(), frame.realData(), nbytes);
    memcpy(imagData(), frame.imagData(), nbytes);
}

Example #4

File: FFTFrame.cpp Project: meshula/LabSound

void FFTFrame::interpolateFrequencyComponents(const FFTFrame& frame1, const FFTFrame& frame2, double interp)
{
    // FIXME : with some work, this method could be optimized

    float* realP = realData();
    float* imagP = imagData();

    const float* realP1 = frame1.realData();
    const float* imagP1 = frame1.imagData();
    const float* realP2 = frame2.realData();
    const float* imagP2 = frame2.imagData();

    m_FFTSize = frame1.fftSize();
    m_log2FFTSize = frame1.log2FFTSize();

    double s1base = (1.0 - interp);
    double s2base = interp;

    double phaseAccum = 0.0;
    double lastPhase1 = 0.0;
    double lastPhase2 = 0.0;

    realP[0] = static_cast<float>(s1base * realP1[0] + s2base * realP2[0]);
    imagP[0] = static_cast<float>(s1base * imagP1[0] + s2base * imagP2[0]);

    int n = m_FFTSize / 2;

    for (int i = 1; i < n; ++i) {
        Complex c1(realP1[i], imagP1[i]);
        Complex c2(realP2[i], imagP2[i]);

        double mag1 = abs(c1);
        double mag2 = abs(c2);

        // Interpolate magnitudes in decibels
        double mag1db = 20.0 * log10(mag1);
        double mag2db = 20.0 * log10(mag2);

        double s1 = s1base;
        double s2 = s2base;

        double magdbdiff = mag1db - mag2db;

        // Empirical tweak to retain higher-frequency zeroes
        double threshold =  (i > 16) ? 5.0 : 2.0;

        if (magdbdiff < -threshold && mag1db < 0.0) 
        {
            s1 = pow(s1, 0.75);
            s2 = 1.0 - s1;
        } else if (magdbdiff > threshold && mag2db < 0.0)
        {
            s2 = pow(s2, 0.75);
            s1 = 1.0 - s2;
        }

        // Average magnitude by decibels instead of linearly
        double magdb = s1 * mag1db + s2 * mag2db;
        double mag = pow(10.0, 0.05 * magdb);

        // Now, deal with phase
        double phase1 = arg(c1);
        double phase2 = arg(c2);

        double deltaPhase1 = phase1 - lastPhase1;
        double deltaPhase2 = phase2 - lastPhase2;
        lastPhase1 = phase1;
        lastPhase2 = phase2;

        // Unwrap phase deltas
        if (deltaPhase1 > piDouble)
            deltaPhase1 -= 2.0 * piDouble;
        if (deltaPhase1 < -piDouble)
            deltaPhase1 += 2.0 * piDouble;
        if (deltaPhase2 > piDouble)
            deltaPhase2 -= 2.0 * piDouble;
        if (deltaPhase2 < -piDouble)
            deltaPhase2 += 2.0 * piDouble;

        // Blend group-delays
        double deltaPhaseBlend;

        if (deltaPhase1 - deltaPhase2 > piDouble)
            deltaPhaseBlend = s1 * deltaPhase1 + s2 * (2.0 * piDouble + deltaPhase2);
        else if (deltaPhase2 - deltaPhase1 > piDouble)
            deltaPhaseBlend = s1 * (2.0 * piDouble + deltaPhase1) + s2 * deltaPhase2;
        else
            deltaPhaseBlend = s1 * deltaPhase1 + s2 * deltaPhase2;

        phaseAccum += deltaPhaseBlend;

        // Unwrap
        if (phaseAccum > piDouble)
            phaseAccum -= 2.0 * piDouble;
        if (phaseAccum < -piDouble)
            phaseAccum += 2.0 * piDouble;

        Complex c = std::polar(mag, phaseAccum);

        realP[i] = static_cast<float>(c.real());
        imagP[i] = static_cast<float>(c.imag());
    }
}