view widgets/WindowShapePreview.cpp @ 1155:d1bab6a99100 project-file-rework

Cut down vastly on the number of config.pri files and places where their contents has to be effectively duplicated without them
author Chris Cannam
date Mon, 24 Oct 2016 17:53:33 +0100
parents c5a82068bd60
children 07e8ac88bcce
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/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Sonic Visualiser
    An audio file viewer and annotation editor.
    Centre for Digital Music, Queen Mary, University of London.
    This file copyright 2006 Chris Cannam.
    
    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.  See the file
    COPYING included with this distribution for more information.
*/

#include "WindowShapePreview.h"

#include <QHBoxLayout>
#include <QLabel>
#include <QPainter>
#include <QPainterPath>
#include <QFont>
#include <QString>

#include "data/fft/FFTapi.h"

#include <iostream>


WindowShapePreview::WindowShapePreview(QWidget *parent) :
    QFrame(parent),
    m_windowType(HanningWindow)
{
    QHBoxLayout *layout = new QHBoxLayout;
    layout->setMargin(0);
    setLayout(layout);
    m_windowTimeExampleLabel = new QLabel;
    m_windowFreqExampleLabel = new QLabel;
    layout->addWidget(m_windowTimeExampleLabel);
    layout->addWidget(m_windowFreqExampleLabel);
}

WindowShapePreview::~WindowShapePreview()
{
}

void
WindowShapePreview::updateLabels()
{
    int step = 24;
    float peak = 48;
    int w = step * 4, h = 64;
    WindowType type = m_windowType;
    Window<float> windower = Window<float>(type, step * 2);

    QPixmap timeLabel(w, h + 1);
    timeLabel.fill(Qt::white);
    QPainter timePainter(&timeLabel);

    QPainterPath path;

    path.moveTo(0, float(h) - peak + 1);
    path.lineTo(w, float(h) - peak + 1);

    timePainter.setPen(Qt::gray);
    timePainter.setRenderHint(QPainter::Antialiasing, true);
    timePainter.drawPath(path);
    
    path = QPainterPath();

    float *acc = new float[w];
    for (int i = 0; i < w; ++i) acc[i] = 0.f;
    for (int j = 0; j < 3; ++j) {
        for (int i = 0; i < step * 2; ++i) {
            acc[j * step + i] += windower.getValue(i);
        }
    }
    for (int i = 0; i < w; ++i) {
        int y = h - int(peak * acc[i] + 0.001f) + 1;
        if (i == 0) path.moveTo(i, y);
        else path.lineTo(i, y);
    }
    delete[] acc;

    timePainter.drawPath(path);
    timePainter.setRenderHint(QPainter::Antialiasing, false);

    path = QPainterPath();

    timePainter.setPen(Qt::black);
    
    for (int i = 0; i < step * 2; ++i) {
        int y = h - int(peak * windower.getValue(i) + 0.001) + 1;
        if (i == 0) path.moveTo(i + step, float(y));
        else path.lineTo(i + step, float(y));
    }

    if (type == RectangularWindow) {
        timePainter.drawPath(path);
        path = QPainterPath();
    }

    timePainter.setRenderHint(QPainter::Antialiasing, true);
    path.addRect(0, 0, w, h + 1);
    timePainter.drawPath(path);

    QFont font;
    font.setPixelSize(10);
    font.setItalic(true);
    timePainter.setFont(font);
    QString label = tr("V / time");
    timePainter.drawText(w - timePainter.fontMetrics().width(label) - 4,
                         timePainter.fontMetrics().ascent() + 1, label);

    m_windowTimeExampleLabel->setPixmap(timeLabel);
    
    int fw = 100;

    QPixmap freqLabel(fw, h + 1);
    freqLabel.fill(Qt::white);
    QPainter freqPainter(&freqLabel);
    path = QPainterPath();

    int fftsize = 512;

    float *input = (float *)fftf_malloc(fftsize * sizeof(float));
    fftf_complex *output =
        (fftf_complex *)fftf_malloc(fftsize * sizeof(fftf_complex));
    fftf_plan plan = fftf_plan_dft_r2c_1d(fftsize, input, output,
                                            FFTW_ESTIMATE);
    for (int i = 0; i < fftsize; ++i) input[i] = 0.f;
    for (int i = 0; i < step * 2; ++i) {
        input[fftsize/2 - step + i] = windower.getValue(i);
    }
    
    fftf_execute(plan);
    fftf_destroy_plan(plan);

    float maxdb = 0.f;
    float mindb = 0.f;
    bool first = true;
    for (int i = 0; i < fftsize/2; ++i) {
        float power = output[i][0] * output[i][0] + output[i][1] * output[i][1];
        float db = mindb;
        if (power > 0) {
            db = 20.f * log10f(power);
            if (first || db > maxdb) maxdb = db;
            if (first || db < mindb) mindb = db;
            first = false;
        }
    }

    if (mindb > -80.f) mindb = -80.f;

    // -- no, don't use the actual mindb -- it's easier to compare
    // plots with a fixed min value
    mindb = -170.f;

    float maxval = maxdb + -mindb;

//    float ly = h - ((-80.f + -mindb) / maxval) * peak + 1;

    path.moveTo(0, float(h) - peak + 1);
    path.lineTo(fw, float(h) - peak + 1);

    freqPainter.setPen(Qt::gray);
    freqPainter.setRenderHint(QPainter::Antialiasing, true);
    freqPainter.drawPath(path);
    
    path = QPainterPath();
    freqPainter.setPen(Qt::black);

//    cerr << "maxdb = " << maxdb << ", mindb = " << mindb << ", maxval = " <<maxval << endl;

    for (int i = 0; i < fftsize/2; ++i) {
        float power = output[i][0] * output[i][0] + output[i][1] * output[i][1];
        float db = 20.f * log10f(power);
        float val = db + -mindb;
        if (val < 0) val = 0;
        float norm = val / maxval;
        float x = (float(fw) / float(fftsize/2)) * float(i);
        float y = float(h) - norm * peak + 1;
        if (i == 0) path.moveTo(x, y);
        else path.lineTo(x, y);
    }

    freqPainter.setRenderHint(QPainter::Antialiasing, true);
    path.addRect(0, 0, fw, h + 1);
    freqPainter.drawPath(path);

    fftf_free(input);
    fftf_free(output);

    freqPainter.setFont(font);
    label = tr("dB / freq");
    freqPainter.drawText(fw - freqPainter.fontMetrics().width(label) - 4,
                         freqPainter.fontMetrics().ascent() + 1, label);

    m_windowFreqExampleLabel->setPixmap(freqLabel);
}

void
WindowShapePreview::setWindowType(WindowType type)
{
    m_windowType = type;
    updateLabels();
}