+/***************************************************************************
+ * 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 "audiospectrum.h"
+#include "ffttools.h"
#include "tools/kiss_fftr.h"
#include <QMenu>
+#include <QPainter>
+#include <QMouseEvent>
+
+#include <iostream>
-//#include <iostream>
-//#include <fstream>
+// (defined in the header file)
+#ifdef DEBUG_AUDIOSPEC
+#include <QDebug>
+#endif
-bool fileWritten = false;
+// Draw lines instead of single pixels.
+// This is about 25 % faster, especially when enlarging the scope to e.g. 1680x1050 px.
+#define AUDIOSPEC_LINES
-AudioSpectrum::AudioSpectrum(Monitor *projMonitor, Monitor *clipMonitor, QWidget *parent) :
- AbstractAudioScopeWidget(projMonitor, clipMonitor, true, parent)
+#define MIN_DB_VALUE -120
+#define MAX_FREQ_VALUE 96000
+#define MIN_FREQ_VALUE 1000
+
+AudioSpectrum::AudioSpectrum(QWidget *parent) :
+ AbstractAudioScopeWidget(true, parent),
+ m_fftTools(),
+ m_lastFFT(),
+ m_lastFFTLock(1)
+ #ifdef DEBUG_AUDIOSPEC
+ ,m_timeTotal(0)
+ ,m_showTotal(0)
+ #endif
{
ui = new Ui::AudioSpectrum_UI;
ui->setupUi(this);
- m_cfg = kiss_fftr_alloc(512, 0,0,0);
- m_aLin = new QAction(i18n("Linear scale"), this);
- m_aLin->setCheckable(true);
- m_aLog = new QAction(i18n("Logarithmic scale"), this);
- m_aLog->setCheckable(true);
+ m_aResetHz = new QAction(i18n("Reset maximum frequency to sampling rate"), this);
+ m_aTrackMouse = new QAction(i18n("Track mouse"), this);
+ m_aTrackMouse->setCheckable(true);
+
+
+ m_menu->addSeparator();
+ m_menu->addAction(m_aResetHz);
+ m_menu->addAction(m_aTrackMouse);
+ m_menu->removeAction(m_aRealtime);
+
- m_agScale = new QActionGroup(this);
- m_agScale->addAction(m_aLin);
- m_agScale->addAction(m_aLog);
+ ui->windowSize->addItem("256", QVariant(256));
+ ui->windowSize->addItem("512", QVariant(512));
+ ui->windowSize->addItem("1024", QVariant(1024));
+ ui->windowSize->addItem("2048", QVariant(2048));
- m_menu->addSeparator()->setText(i18n("Scale"));
- m_menu->addAction(m_aLin);
- m_menu->addAction(m_aLog);
+ ui->windowFunction->addItem(i18n("Rectangular window"), FFTTools::Window_Rect);
+ ui->windowFunction->addItem(i18n("Triangular window"), FFTTools::Window_Triangle);
+ ui->windowFunction->addItem(i18n("Hamming window"), FFTTools::Window_Hamming);
- init();
+
+ bool b = true;
+ b &= connect(m_aResetHz, SIGNAL(triggered()), this, SLOT(slotResetMaxFreq()));
+ b &= connect(ui->windowFunction, SIGNAL(currentIndexChanged(int)), this, SLOT(forceUpdate()));
+ b &= connect(this, SIGNAL(signalMousePositionChanged()), this, SLOT(forceUpdateHUD()));
+ Q_ASSERT(b);
+
+
+ // Note: These strings are used in both Spectogram and AudioSpectrum. Ideally change both (if necessary) to reduce workload on translators
+ ui->labelFFTSize->setToolTip(i18n("The maximum window size is limited by the number of samples per frame."));
+ ui->windowSize->setToolTip(i18n("A bigger window improves the accuracy at the cost of computational power."));
+ ui->windowFunction->setToolTip(i18n("The rectangular window function is good for signals with equal signal strength (narrow peak), but creates more smearing. See Window function on Wikipedia."));
+
+ AbstractScopeWidget::init();
}
AudioSpectrum::~AudioSpectrum()
{
- free(m_cfg);
- delete m_agScale;
- delete m_aLin;
- delete m_aLog;
+ writeConfig();
+
+ delete m_aResetHz;
+ delete m_aTrackMouse;
}
void AudioSpectrum::readConfig()
{
- AbstractAudioScopeWidget::readConfig();
+ AbstractScopeWidget::readConfig();
KSharedConfigPtr config = KGlobal::config();
- KConfigGroup scopeConfig(config, configName());
- QString scale = scopeConfig.readEntry("scale");
- if (scale == "lin") {
- m_aLin->setChecked(true);
+ KConfigGroup scopeConfig(config, AbstractScopeWidget::configName());
+
+ ui->windowSize->setCurrentIndex(scopeConfig.readEntry("windowSize", 0));
+ ui->windowFunction->setCurrentIndex(scopeConfig.readEntry("windowFunction", 0));
+ m_aTrackMouse->setChecked(scopeConfig.readEntry("trackMouse", true));
+ m_dBmax = scopeConfig.readEntry("dBmax", 0);
+ m_dBmin = scopeConfig.readEntry("dBmin", -70);
+ m_freqMax = scopeConfig.readEntry("freqMax", 0);
+
+ if (m_freqMax == 0) {
+ m_customFreq = false;
+ m_freqMax = 10000;
} else {
- m_aLog->setChecked(true);
+ m_customFreq = true;
}
-
}
void AudioSpectrum::writeConfig()
{
KSharedConfigPtr config = KGlobal::config();
- KConfigGroup scopeConfig(config, configName());
- QString scale;
- if (m_aLin->isChecked()) {
- scale = "lin";
+ KConfigGroup scopeConfig(config, AbstractScopeWidget::configName());
+
+ scopeConfig.writeEntry("windowSize", ui->windowSize->currentIndex());
+ scopeConfig.writeEntry("windowFunction", ui->windowFunction->currentIndex());
+ scopeConfig.writeEntry("trackMouse", m_aTrackMouse->isChecked());
+ scopeConfig.writeEntry("dBmax", m_dBmax);
+ scopeConfig.writeEntry("dBmin", m_dBmin);
+ if (m_customFreq) {
+ scopeConfig.writeEntry("freqMax", m_freqMax);
} else {
- scale = "log";
+ scopeConfig.writeEntry("freqMax", 0);
}
- scopeConfig.writeEntry("scale", scale);
+
scopeConfig.sync();
}
-QString AudioSpectrum::widgetName() const { return QString("audiospectrum"); }
-
+QString AudioSpectrum::widgetName() const { return QString("AudioSpectrum"); }
bool AudioSpectrum::isBackgroundDependingOnInput() const { return false; }
bool AudioSpectrum::isScopeDependingOnInput() const { return true; }
bool AudioSpectrum::isHUDDependingOnInput() const { return false; }
QImage AudioSpectrum::renderBackground(uint) { return QImage(); }
-QImage AudioSpectrum::renderScope(uint, const QVector<int16_t> audioFrame, const int freq, const int num_channels, const int num_samples)
+
+QImage AudioSpectrum::renderAudioScope(uint, const QVector<int16_t> audioFrame, const int freq, const int num_channels,
+ const int num_samples, const int)
{
- QTime start = QTime::currentTime();
- float data[512];
+ if (audioFrame.size() > 63) {
+ if (!m_customFreq) {
+ m_freqMax = freq / 2;
+ }
+
+ QTime start = QTime::currentTime();
+
+
+ // Determine the window size to use. It should be
+ // * not bigger than the number of samples actually available
+ // * divisible by 2
+ int fftWindow = ui->windowSize->itemData(ui->windowSize->currentIndex()).toInt();
+ if (fftWindow > num_samples) {
+ fftWindow = num_samples;
+ }
+ if ((fftWindow & 1) == 1) {
+ fftWindow--;
+ }
+
+ // Show the window size used, for information
+ ui->labelFFTSizeNumber->setText(QVariant(fftWindow).toString());
+
+
+ // Get the spectral power distribution of the input samples,
+ // using the given window size and function
+ float freqSpectrum[fftWindow/2];
+ FFTTools::WindowType windowType = (FFTTools::WindowType) ui->windowFunction->itemData(ui->windowFunction->currentIndex()).toInt();
+ m_fftTools.fftNormalized(audioFrame, 0, num_channels, freqSpectrum, windowType, fftWindow, 0);
- // The resulting FFT vector is only half as long
- kiss_fft_cpx freqData[256];
- // Copy the first channel's audio into a vector for the FFT display
- // (only one channel handled at the moment)
- for (int i = 0; i < 512; i++) {
- data[i] = (float) audioFrame.data()[i*num_channels];
+ // Store the current FFT window (for the HUD) and run the interpolation
+ // for easy pixel-based dB value access
+ QVector<float> dbMap;
+ m_lastFFTLock.acquire();
+ m_lastFFT = QVector<float>(fftWindow/2);
+ memcpy(m_lastFFT.data(), &(freqSpectrum[0]), fftWindow/2 * sizeof(float));
+
+ uint right = ((float) m_freqMax)/(m_freq) * (m_lastFFT.size() - 1);
+ dbMap = interpolatePeakPreserving(m_lastFFT, m_innerScopeRect.width(), 0, right, -120);
+ m_lastFFTLock.release();
+
+
+ QTime drawTime = QTime::currentTime();
+
+ // Draw the spectrum
+ QImage spectrum(m_scopeRect.size(), QImage::Format_ARGB32);
+ spectrum.fill(qRgba(0,0,0,0));
+ const uint w = m_innerScopeRect.width();
+ const uint h = m_innerScopeRect.height();
+ const uint leftDist = m_innerScopeRect.left() - m_scopeRect.left();
+ const uint topDist = m_innerScopeRect.top() - m_scopeRect.top();
+ int yMax;
+
+#ifdef AUDIOSPEC_LINES
+ QPainter davinci(&spectrum);
+ davinci.setPen(AbstractScopeWidget::penThin);
+#endif
+
+ for (uint i = 0; i < w; i++) {
+ yMax = (dbMap[i] - m_dBmin) / (m_dBmax-m_dBmin) * (h-1);
+ if (yMax < 0) {
+ yMax = 0;
+ } else if (yMax >= (int)h) {
+ yMax = h-1;
+ }
+#ifdef AUDIOSPEC_LINES
+ davinci.drawLine(leftDist + i, topDist + h-1, leftDist + i, topDist + h-1 - yMax);
+#else
+ for (int y = 0; y < yMax && y < (int)h; y++) {
+ spectrum.setPixel(leftDist + i, topDist + h-y-1, qRgba(225, 182, 255, 255));
+ }
+#endif
+ }
+
+#ifdef DEBUG_AUDIOSPEC
+ m_showTotal++;
+ m_timeTotal += drawTime.elapsed();
+ qDebug() << widgetName() << " took " << drawTime.elapsed() << " ms for drawing. Average: " << ((float)m_timeTotal/m_showTotal) ;
+#endif
+
+ emit signalScopeRenderingFinished(start.elapsed(), 1);
+
+
+ return spectrum;
+ } else {
+ emit signalScopeRenderingFinished(0, 1);
+ return QImage();
}
- // Calculate the Fast Fourier Transform for the input data
- kiss_fftr(m_cfg, data, freqData);
-
-// qDebug() << num_samples << " samples at " << freq << " Hz";
-// qDebug() << "FFT Freq: " << freqData[0].r << " " << freqData[1].r << ", " << freqData[2].r;
-// qDebug() << "FFT imag: " << freqData[0].i << " " << freqData[1].i << ", " << freqData[2].i;
-
-
- float max = 0;
- float maxSignal = 0;
- float min = 1000;
- float val;
- // Get the minimum and the maximum value of the Fourier transformed (for scaling)
- for (int i = 0; i < 256; i++) {
- // sqrt(r² + i²)
- val = pow(pow(fabs(freqData[i].r),2) + pow(fabs(freqData[i].i),2), .5);
- if (maxSignal < val) { maxSignal = val; }
- if (!m_aLin->isChecked()) {
- // Logarithmic scale
- val = log(pow(pow(fabs(freqData[i].r),2) + pow(fabs(freqData[i].i),2), .5)/512.0f);
- }
- max = (max > val) ? max : val;
- min = (min < val) ? min : val;
+}
+QImage AudioSpectrum::renderHUD(uint)
+{
+ QTime start = QTime::currentTime();
+
+ // Minimum distance between two lines
+ const uint minDistY = 30;
+ const uint minDistX = 40;
+ const uint textDistX = 10;
+ const uint textDistY = 25;
+ const uint topDist = m_innerScopeRect.top() - m_scopeRect.top();
+ const uint leftDist = m_innerScopeRect.left() - m_scopeRect.left();
+ const uint dbDiff = ceil((float)minDistY/m_innerScopeRect.height() * (m_dBmax-m_dBmin));
+ const int mouseX = m_mousePos.x() - m_innerScopeRect.left();
+ const int mouseY = m_mousePos.y() - m_innerScopeRect.top();
+
+ QImage hud(m_scopeRect.size(), QImage::Format_ARGB32);
+ hud.fill(qRgba(0,0,0,0));
+
+ QPainter davinci(&hud);
+ davinci.setPen(AbstractScopeWidget::penLight);
+
+ int y;
+ for (int db = -dbDiff; db > m_dBmin; db -= dbDiff) {
+ y = topDist + m_innerScopeRect.height() * ((float)db)/(m_dBmin - m_dBmax);
+ if (y-topDist > m_innerScopeRect.height()-minDistY+10) {
+ // Abort here, there is still a line left for min dB to paint which needs some room.
+ break;
+ }
+ davinci.drawLine(leftDist, y, leftDist + m_innerScopeRect.width()-1, y);
+ davinci.drawText(leftDist + m_innerScopeRect.width() + textDistX, y + 6, i18n("%1 dB", m_dBmax + db));
}
- qDebug() << "MAX: " << max << " (" << maxSignal << "), MIN: " << min;
+ davinci.drawLine(leftDist, topDist, leftDist + m_innerScopeRect.width()-1, topDist);
+ davinci.drawText(leftDist + m_innerScopeRect.width() + textDistX, topDist+6, i18n("%1 dB", m_dBmax));
+ davinci.drawLine(leftDist, topDist+m_innerScopeRect.height()-1, leftDist + m_innerScopeRect.width()-1, topDist+m_innerScopeRect.height()-1);
+ davinci.drawText(leftDist + m_innerScopeRect.width() + textDistX, topDist+m_innerScopeRect.height()+6, i18n("%1 dB", m_dBmin));
- // Scaling factor
- float factor = 100./(max-min);
+ const uint hzDiff = ceil( ((float)minDistX)/m_innerScopeRect.width() * m_freqMax / 1000 ) * 1000;
+ int x = 0;
+ const int rightBorder = leftDist + m_innerScopeRect.width()-1;
+ y = topDist + m_innerScopeRect.height() + textDistY;
+ for (uint hz = 0; x <= rightBorder; hz += hzDiff) {
+ davinci.setPen(AbstractScopeWidget::penLight);
+ x = leftDist + m_innerScopeRect.width() * ((float)hz)/m_freqMax;
- // Draw the spectrum
- QImage spectrum(512, 100, QImage::Format_ARGB32);
- spectrum.fill(qRgba(0,0,0,0));
- for (int i = 0; i < 256; i++) {
- if (m_aLin->isChecked()) {
- val = pow(pow(fabs(freqData[i].r),2) + pow(fabs(freqData[i].i),2), .5);
+ if (x <= rightBorder) {
+ davinci.drawLine(x, topDist, x, topDist + m_innerScopeRect.height()+6);
+ }
+ if (hz < m_freqMax && x+textDistY < leftDist + m_innerScopeRect.width()) {
+ davinci.drawText(x-4, y, QVariant(hz/1000).toString());
} else {
- val = log(pow(pow(fabs(freqData[i].r),2) + pow(fabs(freqData[i].i),2), .5)/512.0f);
+ x = leftDist + m_innerScopeRect.width();
+ davinci.drawLine(x, topDist, x, topDist + m_innerScopeRect.height()+6);
+ davinci.drawText(x-10, y, i18n("%1 kHz").arg((double)m_freqMax/1000, 0, 'f', 1));
}
- //val = val >> 16;
- val = factor * (val-min);
-// qDebug() << val;
- for (int y = 0; y < val && y < 100; y++) {
- spectrum.setPixel(2*i, 99-y, qRgba(225, 182, 255, 255));
- spectrum.setPixel(2*i+1, 99-y, qRgba(225, 182, 255, 255));
+
+ if (hz > 0) {
+ // Draw finer lines between the main lines
+ davinci.setPen(AbstractScopeWidget::penLightDots);
+ for (uint dHz = 3; dHz > 0; dHz--) {
+ x = leftDist + m_innerScopeRect.width() * ((float)hz - dHz * hzDiff/4.0f)/m_freqMax;
+ if (x > rightBorder) {
+ break;
+ }
+ davinci.drawLine(x, topDist, x, topDist + m_innerScopeRect.height()-1);
+ }
}
}
- emit signalScopeRenderingFinished(start.elapsed(), 1);
+ if (m_aTrackMouse->isChecked() && m_mouseWithinWidget && mouseX < m_innerScopeRect.width()-1) {
+ davinci.setPen(AbstractScopeWidget::penThin);
- /*
- if (!fileWritten || true) {
- std::ofstream mFile;
- mFile.open("/tmp/freq.m");
- if (!mFile) {
- qDebug() << "Opening file failed.";
- } else {
- mFile << "val = [ ";
+ x = leftDist + mouseX;
+
+ float db = 0;
+ float freq = ((float) mouseX)/(m_innerScopeRect.width()-1) * m_freqMax;
+ bool drawDb = false;
- for (int sample = 0; sample < 256; sample++) {
- mFile << data[sample] << " ";
+ m_lastFFTLock.acquire();
+ // We need to test whether the mouse is inside the widget
+ // because the position could already have changed in the meantime (-> crash)
+ if (m_lastFFT.size() > 0 && mouseX >= 0 && mouseX < m_innerScopeRect.width()) {
+ uint right = ((float) m_freqMax)/(m_freq) * (m_lastFFT.size() - 1);
+ QVector<float> dbMap = AudioSpectrum::interpolatePeakPreserving(m_lastFFT, m_innerScopeRect.width(), 0, right, -120);
+
+ db = dbMap[mouseX];
+ y = topDist + m_innerScopeRect.height()-1 - (dbMap[mouseX] - m_dBmin) / (m_dBmax-m_dBmin) * (m_innerScopeRect.height()-1);
+
+ if (y < (int)topDist + m_innerScopeRect.height()-1) {
+ drawDb = true;
+ davinci.drawLine(x, y, leftDist + m_innerScopeRect.width()-1, y);
}
- mFile << " ];\n";
+ } else {
+ y = topDist + mouseY;
+ }
+ m_lastFFTLock.release();
+
+ if (y > (int)topDist + mouseY) {
+ y = topDist+ mouseY;
+ }
+ davinci.drawLine(x, y, x, topDist + m_innerScopeRect.height()-1);
- mFile << "freq = [ ";
- for (int sample = 0; sample < 256; sample++) {
- mFile << freqData[sample].r << "+" << freqData[sample].i << "*i ";
+ if (drawDb) {
+ QPoint dist(20, -20);
+ QRect rect(
+ leftDist + mouseX + dist.x(),
+ topDist + mouseY + dist.y(),
+ 100,
+ 40
+ );
+ if (rect.right() > (int)leftDist + m_innerScopeRect.width()-1) {
+ // Mirror the rectangle at the y axis to keep it inside the widget
+ rect = QRect(
+ rect.topLeft() - QPoint(rect.width() + 2*dist.x(), 0),
+ rect.size());
}
- mFile << " ];\n";
- mFile.close();
- fileWritten = true;
- qDebug() << "File written.";
+ QRect textRect(
+ rect.topLeft() + QPoint(12, 4),
+ rect.size()
+ );
+
+ davinci.fillRect(rect, AbstractScopeWidget::penBackground.brush());
+ davinci.setPen(AbstractScopeWidget::penLighter);
+ davinci.drawRect(rect);
+ davinci.drawText(textRect, QString(
+ i18n("%1 dB", QString("%1").arg(db, 0, 'f', 2))
+ + "\n"
+ + i18n("%1 kHz", QString("%1").arg(freq/1000, 0, 'f', 2))));
}
- } else {
- qDebug() << "File already written.";
+
}
- */
- return spectrum;
+
+ emit signalHUDRenderingFinished(start.elapsed(), 1);
+ return hud;
+}
+
+QRect AudioSpectrum::scopeRect()
+{
+ m_scopeRect = QRect(
+ QPoint(
+ 10, // Left
+ ui->verticalSpacer->geometry().top()+6 // Top
+ ),
+ AbstractAudioScopeWidget::rect().bottomRight()
+ );
+ m_innerScopeRect = QRect(
+ QPoint(
+ m_scopeRect.left()+6, // Left
+ m_scopeRect.top()+6 // Top
+ ), QPoint(
+ ui->verticalSpacer->geometry().right()-70,
+ ui->verticalSpacer->geometry().bottom()-40
+ )
+ );
+ return m_scopeRect;
+}
+
+void AudioSpectrum::slotResetMaxFreq()
+{
+ m_customFreq = false;
+ forceUpdateHUD();
+ forceUpdateScope();
+}
+
+
+///// EVENTS /////
+
+void AudioSpectrum::handleMouseDrag(const QPoint movement, const RescaleDirection rescaleDirection, const Qt::KeyboardModifiers rescaleModifiers)
+{
+ if (rescaleDirection == North) {
+ // Nort-South direction: Adjust the dB scale
+
+ if ((rescaleModifiers & Qt::ShiftModifier) == 0) {
+
+ // By default adjust the min dB value
+ m_dBmin += movement.y();
+
+ } else {
+
+ // Adjust max dB value if Shift is pressed.
+ m_dBmax += movement.y();
+
+ }
+
+ // Ensure the dB values lie in [-100, 0] (or rather [MIN_DB_VALUE, 0])
+ // 0 is the upper bound, everything below -70 dB is most likely noise
+ if (m_dBmax > 0) {
+ m_dBmax = 0;
+ }
+ if (m_dBmin < MIN_DB_VALUE) {
+ m_dBmin = MIN_DB_VALUE;
+ }
+ // Ensure there is at least 6 dB between the minimum and the maximum value;
+ // lower values hardly make sense
+ if (m_dBmax - m_dBmin < 6) {
+ if ((rescaleModifiers & Qt::ShiftModifier) == 0) {
+ // min was adjusted; Try to adjust the max value to maintain the
+ // minimum dB difference of 6 dB
+ m_dBmax = m_dBmin + 6;
+ if (m_dBmax > 0) {
+ m_dBmax = 0;
+ m_dBmin = -6;
+ }
+ } else {
+ // max was adjusted, adjust min
+ m_dBmin = m_dBmax - 6;
+ if (m_dBmin < MIN_DB_VALUE) {
+ m_dBmin = MIN_DB_VALUE;
+ m_dBmax = MIN_DB_VALUE+6;
+ }
+ }
+ }
+
+ forceUpdateHUD();
+ forceUpdateScope();
+
+ } else if (rescaleDirection == East) {
+ // East-West direction: Adjust the maximum frequency
+ m_freqMax -= 100*movement.x();
+ if (m_freqMax < MIN_FREQ_VALUE) {
+ m_freqMax = MIN_FREQ_VALUE;
+ }
+ if (m_freqMax > MAX_FREQ_VALUE) {
+ m_freqMax = MAX_FREQ_VALUE;
+ }
+ m_customFreq = true;
+
+ forceUpdateHUD();
+ forceUpdateScope();
+ }
}
-QImage AudioSpectrum::renderHUD(uint) { return QImage(); }
-QRect AudioSpectrum::scopeRect() {
- return QRect(0,0,40,40);
+
+const QVector<float> AudioSpectrum::interpolatePeakPreserving(const QVector<float> in, const uint targetSize, uint left, uint right, float fill)
+{
+#ifdef DEBUG_AUDIOSPEC
+ 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;
+ int xi;
+ uint i;
+ 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 (i == 0 || i == targetSize-1) {
+ // ... except if we are at the left or right border of the display or the spectrum
+ 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;
+ }
+ // Fill the rest of the vector if the right border exceeds the input vector.
+ for (; i < targetSize; i++) {
+ out[i] = fill;
+ }
+
+#ifdef DEBUG_AUDIOSPEC
+ qDebug() << "Interpolated " << targetSize << " nodes from " << in.size() << " input points in " << start.elapsed() << " ms";
+#endif
+
+ return out;
}
+
+
+#ifdef DEBUG_AUDIOSPEC
+#undef DEBUG_AUDIOSPEC
+#endif
+
+#undef MIN_DB_VALUE
+#undef MAX_FREQ_VALUE
+#undef MIN_FREQ_VALUE
projects / kdenlive / blobdiff