+++ /dev/null
-/***************************************************************************
- * Copyright (C) 2010 by Simon Andreas Eugster (simon.eu@gmail.com) *
- * This file is part of kdenlive. See www.kdenlive.org. *
- * *
- * This program is free software; you can redistribute it and/or modify *
- * it under the terms of the GNU General Public License as published by *
- * the Free Software Foundation; either version 2 of the License, or *
- * (at your option) any later version. *
- ***************************************************************************/
-
-#include <math.h>
-#include <iostream>
-
-#include <QString>
-
-#include "ffttools.h"
-
-// Uncomment for debugging, like writing a GNU Octave .m file to /tmp
-//#define DEBUG_FFTTOOLS
-
-#ifdef DEBUG_FFTTOOLS
-#include <QDebug>
-#include <QTime>
-#include <fstream>
-#endif
-
-FFTTools::FFTTools() :
- m_fftCfgs(),
- m_windowFunctions()
-{
-}
-FFTTools::~FFTTools()
-{
- QHash<QString, kiss_fftr_cfg>::iterator i;
- for (i = m_fftCfgs.begin(); i != m_fftCfgs.end(); i++) {
- free(*i);
- }
-}
-
-const QString FFTTools::windowSignature(const WindowType windowType, const int size, const float param)
-{
- return QString("s%1_t%2_p%3").arg(size).arg(windowType).arg(param, 0, 'f', 3);
-}
-const QString FFTTools::cfgSignature(const int size)
-{
- return QString("s%1").arg(size);
-}
-
-// http://cplusplus.syntaxerrors.info/index.php?title=Cannot_declare_member_function_%E2%80%98static_int_Foo::bar%28%29%E2%80%99_to_have_static_linkage
-const QVector<float> FFTTools::window(const WindowType windowType, const int size, const float param)
-{
- Q_ASSERT(size > 0);
-
- // Deliberately avoid converting size to a float
- // to keep mid an integer.
- float mid = (size-1)/2;
- float max = size-1;
- QVector<float> window;
-
- switch (windowType) {
- case Window_Rect:
- return QVector<float>(size+1, 1);
- break;
- case Window_Triangle:
- window = QVector<float>(size+1);
-
- for (int x = 0; x < mid; x++) {
- window[x] = x/mid + (mid-x)/mid*param;
- }
- for (int x = mid; x < size; x++) {
- window[x] = (x-mid)/(max-mid) * param + (max-x)/(max-mid);
- }
- window[size] = .5 + param/2;
-
-#ifdef DEBUG_FFTTOOLS
- qDebug() << "Triangle window (factor " << window[size] << "):";
- for (int i = 0; i < size; i++) {
- qDebug() << window[i];
- }
- qDebug() << "Triangle window end.";
-#endif
-
- return window;
- break;
- case Window_Hamming:
- // Use a quick version of the Hamming window here: Instead of
- // interpolating values between (-max/2) and (max/2)
- // we use integer values instead, ranging from -mid to (max-mid).
- window = QVector<float>(size+1);
-
- for (int x = 0; x < size; x++) {
- window[x] = .54 + .46 * cos( 2*M_PI*(x-mid) / size );
- }
-
- // Integrating the cosine over the window function results in
- // an area of 0; So only the constant factor 0.54 counts.
- window[size] = .54;
-
-#ifdef DEBUG_FFTTOOLS
- qDebug() << "Hanning window (factor " << window[size] << "):";
- for (int i = 0; i < size; i++) {
- qDebug() << window[i];
- }
- qDebug() << "Hanning window end.";
-#endif
-
- return window;
- break;
- }
- Q_ASSERT(false);
- return QVector<float>();
-}
-
-void FFTTools::fftNormalized(const QVector<int16_t> audioFrame, const uint channel, const uint numChannels, float *freqSpectrum,
- const WindowType windowType, const uint windowSize, const float param)
-{
-#ifdef DEBUG_FFTTOOLS
- QTime start = QTime::currentTime();
-#endif
-
- const uint numSamples = audioFrame.size()/numChannels;
-
- Q_ASSERT((windowSize & 1) == 0);
- Q_ASSERT(windowSize > 0);
-
- const QString cfgSig = cfgSignature(windowSize);
- const QString winSig = windowSignature(windowType, windowSize, param);
-
-
- // Get the kiss_fft configuration from the config cache
- // or build a new configuration if the requested one is not available.
- kiss_fftr_cfg myCfg;
- if (m_fftCfgs.contains(cfgSig)) {
-#ifdef DEBUG_FFTTOOLS
- qDebug() << "Re-using FFT configuration with size " << windowSize;
-#endif
- myCfg = m_fftCfgs.value(cfgSig);
- } else {
-#ifdef DEBUG_FFTTOOLS
- qDebug() << "Creating FFT configuration with size " << windowSize;
-#endif
- myCfg = kiss_fftr_alloc(windowSize, 0,0,0);
- m_fftCfgs.insert(cfgSig, myCfg);
- }
-
- // Get the window function from the cache
- // (except for a rectangular window; nothing to to there.
- QVector<float> window;
- float windowScaleFactor = 1;
- if (windowType != FFTTools::Window_Rect) {
-
- if (m_windowFunctions.contains(winSig)) {
-#ifdef DEBUG_FFTTOOLS
- qDebug() << "Re-using window function with signature " << winSig;
-#endif
- window = m_windowFunctions.value(winSig);
- } else {
-#ifdef DEBUG_FFTTOOLS
- qDebug() << "Building new window function with signature " << winSig;
-#endif
- window = FFTTools::window(windowType, windowSize, 0);
- m_windowFunctions.insert(winSig, window);
- }
- windowScaleFactor = 1.0/window[windowSize];
- }
-
-
- // Prepare frequency space vector. The resulting FFT vector is only half as long.
- kiss_fft_cpx freqData[windowSize/2];
- float data[windowSize];
-
- // Copy the first channel's audio into a vector for the FFT display;
- // Fill the data vector indices that cannot be covered with sample data with 0
- if (numSamples < windowSize) {
- std::fill(&data[numSamples], &data[windowSize-1], 0);
- }
- // Normalize signals to [0,1] to get correct dB values later on
- for (uint i = 0; i < numSamples && i < windowSize; i++) {
- // Performance note: Benchmarking has shown that using the if/else inside the loop
- // does not do noticeable worse than keeping it outside (perhaps the branch predictor
- // is good enough), so it remains in there for better readability.
- if (windowType != FFTTools::Window_Rect) {
- data[i] = (float) audioFrame.data()[i*numChannels + channel] / 32767.0f * window[i];
- } else {
- data[i] = (float) audioFrame.data()[i*numChannels + channel] / 32767.0f;
- }
- }
-
- // Calculate the Fast Fourier Transform for the input data
- kiss_fftr(myCfg, data, freqData);
-
-
- // Logarithmic scale: 20 * log ( 2 * magnitude / N ) with magnitude = sqrt(r² + i²)
- // with N = FFT size (after FFT, 1/2 window size)
- for (uint i = 0; i < windowSize/2; i++) {
- // Logarithmic scale: 20 * log ( 2 * magnitude / N ) with magnitude = sqrt(r² + i²)
- // with N = FFT size (after FFT, 1/2 window size)
- freqSpectrum[i] = 20*log(pow(pow(fabs(freqData[i].r * windowScaleFactor),2) + pow(fabs(freqData[i].i * windowScaleFactor),2), .5)/((float)windowSize/2.0f))/log(10);;
- }
-
-
-#ifdef DEBUG_FFTTOOLS
- std::ofstream mFile;
- mFile.open("/tmp/freq.m");
- if (!mFile) {
- qDebug() << "Opening file failed.";
- } else {
- mFile << "val = [ ";
-
- for (int sample = 0; sample < 256; sample++) {
- mFile << data[sample] << " ";
- }
- mFile << " ];\n";
-
- mFile << "freq = [ ";
- for (int sample = 0; sample < 256; sample++) {
- mFile << freqData[sample].r << "+" << freqData[sample].i << "*i ";
- }
- mFile << " ];\n";
-
- mFile.close();
- qDebug() << "File written.";
- }
-#endif
-
-#ifdef DEBUG_FFTTOOLS
- qDebug() << "Calculated FFT in " << start.elapsed() << " ms.";
-#endif
-}
-
-const QVector<float> FFTTools::interpolatePeakPreserving(const QVector<float> in, const uint targetSize, uint left, uint right, float fill)
-{
-#ifdef DEBUG_FFTTOOLS
- QTime start = QTime::currentTime();
-#endif
-
- if (right == 0) {
- right = in.size()-1;
- }
- Q_ASSERT(targetSize > 0);
- Q_ASSERT(left < right);
-
- QVector<float> out(targetSize);
-
-
- float x;
- float x_prev = 0;
- uint xi;
- uint i;
- if (((float) (right-left))/targetSize < 2) {
- for (i = 0; i < targetSize; i++) {
-
- // i: Target index
- // x: Interpolated source index (float!)
- // xi: floor(x)
-
- // Transform [0,targetSize-1] to [left,right]
- x = ((float) i) / (targetSize-1) * (right-left) + left;
- xi = (int) floor(x);
-
- if (x > in.size()-1) {
- // This may happen if right > in.size()-1; Fill the rest of the vector
- // with the default value now.
- break;
- }
-
-
- // Use linear interpolation in order to get smoother display
- if (xi == 0 || xi == (uint) in.size()-1) {
- // ... except if we are at the left or right border of the input sigal.
- // Special case here since we consider previous and future values as well for
- // the actual interpolation (not possible here).
- out[i] = in[xi];
- } else {
- if (in[xi] > in[xi+1]
- && x_prev < xi) {
- // This is a hack to preserve peaks.
- // Consider f = {0, 100, 0}
- // x = {0.5, 1.5}
- // Then x is 50 both times, and the 100 peak is lost.
- // Get it back here for the first x after the peak (which is at xi).
- // (x is the first after the peak if the previous x was smaller than floor(x).)
- out[i] = in[xi];
- } else {
- out[i] = (xi+1 - x) * in[xi]
- + (x - xi) * in[xi+1];
- }
- }
- x_prev = x;
- }
- } else {
- // If there are more than 2 samples per pixel in average, then use the maximum of them
- // since by only looking at the left sample we might miss some maxima.
- uint src = left;
-// int xi_prev = 0;
- int points;
-
-#ifdef DEBUG_FFTTOOLS
- qDebug() << "Interpolation: Ratio over 2; using maximum interpolation";
-#endif
-
- for (i = 0; i < targetSize; i++) {
-
- // x: right bound
- // xi: floor(x)
- x = ((float) (i+1)) / (targetSize-1) * (right-left) + left;
- xi = (int) floor(x);
- points = 0;
-
- out[i] = fill;
-
- for (; src < xi && src < (uint) in.size(); src++) {
- if (out[i] < in[src]) {
- out[i] = in[src];
- }
- points++;
- }
-
-// xi_prev = xi;
- }
- }
- // Fill the rest of the vector if the right border exceeds the input vector.
- for (; i < targetSize; i++) {
- out[i] = fill;
- }
-
-#ifdef DEBUG_FFTTOOLS
- qDebug() << "Interpolated " << targetSize << " nodes from " << in.size() << " input points in " << start.elapsed() << " ms";
-#endif
-
- return out;
-}
-
-#ifdef DEBUG_FFTTOOLS
-#undef DEBUG_FFTTOOLS
-#endif
projects / kdenlive / blobdiff