view layer/SpectrogramLayer.cpp @ 1534:bfd8b22fd67c

Fix #1904 Scrolling colour 3d plot does not always work when in View normalisation mode. We shouldn't imagine we've just invalidated the cache if the truth is that we've only just created the renderer

/* -*- 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 2006-2009 Chris Cannam and QMUL.
    
    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 "SpectrogramLayer.h"

#include "view/View.h"
#include "base/Profiler.h"
#include "base/AudioLevel.h"
#include "base/Window.h"
#include "base/Pitch.h"
#include "base/Preferences.h"
#include "base/RangeMapper.h"
#include "base/LogRange.h"
#include "base/ColumnOp.h"
#include "base/Strings.h"
#include "base/StorageAdviser.h"
#include "base/Exceptions.h"
#include "widgets/CommandHistory.h"
#include "data/model/Dense3DModelPeakCache.h"

#include "ColourMapper.h"
#include "PianoScale.h"
#include "PaintAssistant.h"
#include "Colour3DPlotRenderer.h"

#include <QPainter>
#include <QImage>
#include <QPixmap>
#include <QRect>
#include <QApplication>
#include <QMessageBox>
#include <QMouseEvent>
#include <QTextStream>
#include <QSettings>

#include <iostream>

#include <cassert>
#include <cmath>

//#define DEBUG_SPECTROGRAM 1
//#define DEBUG_SPECTROGRAM_REPAINT 1

using namespace std;

SpectrogramLayer::SpectrogramLayer(Configuration config) :
    m_channel(0),
    m_windowSize(1024),
    m_windowType(HanningWindow),
    m_windowHopLevel(2),
    m_oversampling(1),
    m_gain(1.0),
    m_initialGain(1.0),
    m_threshold(1.0e-8f),
    m_initialThreshold(1.0e-8f),
    m_colourRotation(0),
    m_initialRotation(0),
    m_minFrequency(10),
    m_maxFrequency(8000),
    m_initialMaxFrequency(8000),
    m_verticallyFixed(false),
    m_colourScale(ColourScaleType::Log),
    m_colourScaleMultiple(1.0),
    m_colourMap(0),
    m_colourInverted(false),
    m_binScale(BinScale::Linear),
    m_binDisplay(BinDisplay::AllBins),
    m_normalization(ColumnNormalization::None),
    m_normalizeVisibleArea(false),
    m_lastEmittedZoomStep(-1),
    m_synchronous(false),
    m_haveDetailedScale(false),
    m_exiting(false),
    m_peakCacheDivisor(8)
{
    QString colourConfigName = "spectrogram-colour";
    int colourConfigDefault = int(ColourMapper::Green);
    
    if (config == FullRangeDb) {
        m_initialMaxFrequency = 0;
        setMaxFrequency(0);
    } else if (config == MelodicRange) {
        setWindowSize(8192);
        setWindowHopLevel(4);
        m_initialMaxFrequency = 1500;
        setMaxFrequency(1500);
        setMinFrequency(40);
        setColourScale(ColourScaleType::Linear);
        setColourMap(ColourMapper::Sunset);
        setBinScale(BinScale::Log);
        colourConfigName = "spectrogram-melodic-colour";
        colourConfigDefault = int(ColourMapper::Sunset);
//        setGain(20);
    } else if (config == MelodicPeaks) {
        setWindowSize(4096);
        setWindowHopLevel(5);
        m_initialMaxFrequency = 2000;
        setMaxFrequency(2000);
        setMinFrequency(40);
        setBinScale(BinScale::Log);
        setColourScale(ColourScaleType::Linear);
        setBinDisplay(BinDisplay::PeakFrequencies);
        setNormalization(ColumnNormalization::Max1);
        colourConfigName = "spectrogram-melodic-colour";
        colourConfigDefault = int(ColourMapper::Sunset);
    }

    QSettings settings;
    settings.beginGroup("Preferences");
    setColourMap(settings.value(colourConfigName, colourConfigDefault).toInt());
    settings.endGroup();
    
    Preferences *prefs = Preferences::getInstance();
    connect(prefs, SIGNAL(propertyChanged(PropertyContainer::PropertyName)),
            this, SLOT(preferenceChanged(PropertyContainer::PropertyName)));
    setWindowType(prefs->getWindowType());
}

SpectrogramLayer::~SpectrogramLayer()
{
    invalidateRenderers();
    deleteDerivedModels();
}

void
SpectrogramLayer::setVerticallyFixed()
{
    if (m_verticallyFixed) return;
    m_verticallyFixed = true;
    recreateFFTModel();
}

void
SpectrogramLayer::deleteDerivedModels()
{
    ModelById::release(m_fftModel);
    ModelById::release(m_peakCache);
    ModelById::release(m_wholeCache);

    m_fftModel = {};
    m_peakCache = {};
    m_wholeCache = {};
}

pair<ColourScaleType, double>
SpectrogramLayer::convertToColourScale(int value)
{
    switch (value) {
    case 0: return { ColourScaleType::Linear, 1.0 };
    case 1: return { ColourScaleType::Meter, 1.0 };
    case 2: return { ColourScaleType::Log, 2.0 }; // dB^2 (i.e. log of power)
    case 3: return { ColourScaleType::Log, 1.0 }; // dB   (of magnitude)
    case 4: return { ColourScaleType::Phase, 1.0 };
    default: return { ColourScaleType::Linear, 1.0 };
    }
}

int
SpectrogramLayer::convertFromColourScale(ColourScaleType scale, double multiple)
{
    switch (scale) {
    case ColourScaleType::Linear: return 0;
    case ColourScaleType::Meter: return 1;
    case ColourScaleType::Log: return (multiple > 1.5 ? 2 : 3);
    case ColourScaleType::Phase: return 4;
    case ColourScaleType::PlusMinusOne:
    case ColourScaleType::Absolute:
    default: return 0;
    }
}

std::pair<ColumnNormalization, bool>
SpectrogramLayer::convertToColumnNorm(int value)
{
    switch (value) {
    default:
    case 0: return { ColumnNormalization::None, false };
    case 1: return { ColumnNormalization::Max1, false };
    case 2: return { ColumnNormalization::None, true }; // visible area
    case 3: return { ColumnNormalization::Hybrid, false };
    }
}

int
SpectrogramLayer::convertFromColumnNorm(ColumnNormalization norm, bool visible)
{
    if (visible) return 2;
    switch (norm) {
    case ColumnNormalization::None: return 0;
    case ColumnNormalization::Max1: return 1;
    case ColumnNormalization::Hybrid: return 3;

    case ColumnNormalization::Sum1:
    case ColumnNormalization::Range01:
    default: return 0;
    }
}

void
SpectrogramLayer::setModel(ModelId modelId)
{
    auto newModel = ModelById::getAs<DenseTimeValueModel>(modelId);
    if (!modelId.isNone() && !newModel) {
        throw std::logic_error("Not a DenseTimeValueModel");
    }
    
    if (modelId == m_model) return;
    m_model = modelId;

    if (newModel) {
        recreateFFTModel();

        connectSignals(m_model);

        connect(newModel.get(),
                SIGNAL(modelChanged(ModelId)),
                this, SLOT(cacheInvalid(ModelId)));
        connect(newModel.get(),
                SIGNAL(modelChangedWithin(ModelId, sv_frame_t, sv_frame_t)),
                this, SLOT(cacheInvalid(ModelId, sv_frame_t, sv_frame_t)));
    }
    
    emit modelReplaced();
}

Layer::PropertyList
SpectrogramLayer::getProperties() const
{
    PropertyList list;
    list.push_back("Colour");
    list.push_back("Colour Scale");
    list.push_back("Window Size");
    list.push_back("Window Increment");
    list.push_back("Oversampling");
    list.push_back("Normalization");
    list.push_back("Bin Display");
    list.push_back("Threshold");
    list.push_back("Gain");
    list.push_back("Colour Rotation");
//    list.push_back("Min Frequency");
//    list.push_back("Max Frequency");
    list.push_back("Frequency Scale");
    return list;
}

QString
SpectrogramLayer::getPropertyLabel(const PropertyName &name) const
{
    if (name == "Colour") return tr("Colour");
    if (name == "Colour Scale") return tr("Colour Scale");
    if (name == "Window Size") return tr("Window Size");
    if (name == "Window Increment") return tr("Window Overlap");
    if (name == "Oversampling") return tr("Oversampling");
    if (name == "Normalization") return tr("Normalization");
    if (name == "Bin Display") return tr("Bin Display");
    if (name == "Threshold") return tr("Threshold");
    if (name == "Gain") return tr("Gain");
    if (name == "Colour Rotation") return tr("Colour Rotation");
    if (name == "Min Frequency") return tr("Min Frequency");
    if (name == "Max Frequency") return tr("Max Frequency");
    if (name == "Frequency Scale") return tr("Frequency Scale");
    return "";
}

QString
SpectrogramLayer::getPropertyIconName(const PropertyName &) const
{
    return "";
}

Layer::PropertyType
SpectrogramLayer::getPropertyType(const PropertyName &name) const
{
    if (name == "Gain") return RangeProperty;
    if (name == "Colour Rotation") return RangeProperty;
    if (name == "Threshold") return RangeProperty;
    if (name == "Colour") return ColourMapProperty;
    return ValueProperty;
}

QString
SpectrogramLayer::getPropertyGroupName(const PropertyName &name) const
{
    if (name == "Bin Display" ||
        name == "Frequency Scale") return tr("Bins");
    if (name == "Window Size" ||
        name == "Window Increment" ||
        name == "Oversampling") return tr("Window");
    if (name == "Colour" ||
        name == "Threshold" ||
        name == "Colour Rotation") return tr("Colour");
    if (name == "Normalization" ||
        name == "Gain" ||
        name == "Colour Scale") return tr("Scale");
    return QString();
}

int
SpectrogramLayer::getPropertyRangeAndValue(const PropertyName &name,
                                           int *min, int *max, int *deflt) const
{
    int val = 0;

    int garbage0, garbage1, garbage2;
    if (!min) min = &garbage0;
    if (!max) max = &garbage1;
    if (!deflt) deflt = &garbage2;

    if (name == "Gain") {

        *min = -50;
        *max = 50;

        *deflt = int(lrint(log10(m_initialGain) * 20.0));
        if (*deflt < *min) *deflt = *min;
        if (*deflt > *max) *deflt = *max;

        val = int(lrint(log10(m_gain) * 20.0));
        if (val < *min) val = *min;
        if (val > *max) val = *max;

    } else if (name == "Threshold") {

        *min = -81;
        *max = -1;

        *deflt = int(lrint(AudioLevel::multiplier_to_dB(m_initialThreshold)));
        if (*deflt < *min) *deflt = *min;
        if (*deflt > *max) *deflt = *max;

        val = int(lrint(AudioLevel::multiplier_to_dB(m_threshold)));
        if (val < *min) val = *min;
        if (val > *max) val = *max;

    } else if (name == "Colour Rotation") {

        *min = 0;
        *max = 256;
        *deflt = m_initialRotation;

        val = m_colourRotation;

    } else if (name == "Colour Scale") {

        // linear, meter, db^2, db, phase
        *min = 0;
        *max = 4;
        *deflt = 2;

        val = convertFromColourScale(m_colourScale, m_colourScaleMultiple);

    } else if (name == "Colour") {

        *min = 0;
        *max = ColourMapper::getColourMapCount() - 1;
        *deflt = 0;

        val = m_colourMap;

    } else if (name == "Window Size") {

        *min = 0;
        *max = 10;
        *deflt = 5;
        
        val = 0;
        int ws = m_windowSize;
        while (ws > 32) { ws >>= 1; val ++; }

    } else if (name == "Window Increment") {
        
        *min = 0;
        *max = 5;
        *deflt = 2;

        val = m_windowHopLevel;

    } else if (name == "Oversampling") {

        *min = 0;
        *max = 3;
        *deflt = 0;

        val = 0;
        int ov = m_oversampling;
        while (ov > 1) { ov >>= 1; val ++; }
        
    } else if (name == "Min Frequency") {

        *min = 0;
        *max = 9;
        *deflt = 1;

        switch (m_minFrequency) {
        case 0: default: val = 0; break;
        case 10: val = 1; break;
        case 20: val = 2; break;
        case 40: val = 3; break;
        case 100: val = 4; break;
        case 250: val = 5; break;
        case 500: val = 6; break;
        case 1000: val = 7; break;
        case 4000: val = 8; break;
        case 10000: val = 9; break;
        }
    
    } else if (name == "Max Frequency") {

        *min = 0;
        *max = 9;
        *deflt = 6;

        switch (m_maxFrequency) {
        case 500: val = 0; break;
        case 1000: val = 1; break;
        case 1500: val = 2; break;
        case 2000: val = 3; break;
        case 4000: val = 4; break;
        case 6000: val = 5; break;
        case 8000: val = 6; break;
        case 12000: val = 7; break;
        case 16000: val = 8; break;
        default: val = 9; break;
        }

    } else if (name == "Frequency Scale") {

        *min = 0;
        *max = 1;
        *deflt = int(BinScale::Linear);
        val = (int)m_binScale;

    } else if (name == "Bin Display") {

        *min = 0;
        *max = 2;
        *deflt = int(BinDisplay::AllBins);
        val = (int)m_binDisplay;

    } else if (name == "Normalization") {
        
        *min = 0;
        *max = 3;
        *deflt = 0;
        
        val = convertFromColumnNorm(m_normalization, m_normalizeVisibleArea);

    } else {
        val = Layer::getPropertyRangeAndValue(name, min, max, deflt);
    }

    return val;
}

QString
SpectrogramLayer::getPropertyValueLabel(const PropertyName &name,
                                        int value) const
{
    if (name == "Colour") {
        return ColourMapper::getColourMapLabel(value);
    }
    if (name == "Colour Scale") {
        switch (value) {
        default:
        case 0: return tr("Linear");
        case 1: return tr("Meter");
        case 2: return tr("dBV^2");
        case 3: return tr("dBV");
        case 4: return tr("Phase");
        }
    }
    if (name == "Normalization") {
        switch(value) {
        default:
        case 0: return tr("None");
        case 1: return tr("Col");
        case 2: return tr("View");
        case 3: return tr("Hybrid");
        }
//        return ""; // icon only
    }
    if (name == "Window Size") {
        return QString("%1").arg(32 << value);
    }
    if (name == "Window Increment") {
        switch (value) {
        default:
        case 0: return tr("None");
        case 1: return tr("25 %");
        case 2: return tr("50 %");
        case 3: return tr("75 %");
        case 4: return tr("87.5 %");
        case 5: return tr("93.75 %");
        }
    }
    if (name == "Oversampling") {
        switch (value) {
        default:
        case 0: return tr("1x");
        case 1: return tr("2x");
        case 2: return tr("4x");
        case 3: return tr("8x");
        }
    }
    if (name == "Min Frequency") {
        switch (value) {
        default:
        case 0: return tr("No min");
        case 1: return tr("10 Hz");
        case 2: return tr("20 Hz");
        case 3: return tr("40 Hz");
        case 4: return tr("100 Hz");
        case 5: return tr("250 Hz");
        case 6: return tr("500 Hz");
        case 7: return tr("1 KHz");
        case 8: return tr("4 KHz");
        case 9: return tr("10 KHz");
        }
    }
    if (name == "Max Frequency") {
        switch (value) {
        default:
        case 0: return tr("500 Hz");
        case 1: return tr("1 KHz");
        case 2: return tr("1.5 KHz");
        case 3: return tr("2 KHz");
        case 4: return tr("4 KHz");
        case 5: return tr("6 KHz");
        case 6: return tr("8 KHz");
        case 7: return tr("12 KHz");
        case 8: return tr("16 KHz");
        case 9: return tr("No max");
        }
    }
    if (name == "Frequency Scale") {
        switch (value) {
        default:
        case 0: return tr("Linear");
        case 1: return tr("Log");
        }
    }
    if (name == "Bin Display") {
        switch (value) {
        default:
        case 0: return tr("All Bins");
        case 1: return tr("Peak Bins");
        case 2: return tr("Frequencies");
        }
    }
    return tr("<unknown>");
}

QString
SpectrogramLayer::getPropertyValueIconName(const PropertyName &name,
                                           int value) const
{
    if (name == "Normalization") {
        switch(value) {
        default:
        case 0: return "normalise-none";
        case 1: return "normalise-columns";
        case 2: return "normalise";
        case 3: return "normalise-hybrid";
        }
    }
    return "";
}

RangeMapper *
SpectrogramLayer::getNewPropertyRangeMapper(const PropertyName &name) const
{
    if (name == "Gain") {
        return new LinearRangeMapper(-50, 50, -25, 25, tr("dB"));
    }
    if (name == "Threshold") {
        return new LinearRangeMapper(-81, -1, -81, -1, tr("dB"), false,
                                     { { -81, Strings::minus_infinity } });
    }
    return nullptr;
}

void
SpectrogramLayer::setProperty(const PropertyName &name, int value)
{
    if (name == "Gain") {
        setGain(float(pow(10, float(value)/20.0)));
    } else if (name == "Threshold") {
        if (value == -81) setThreshold(0.0);
        else setThreshold(float(AudioLevel::dB_to_multiplier(value)));
    } else if (name == "Colour Rotation") {
        setColourRotation(value);
    } else if (name == "Colour") {
        setColourMap(value);
    } else if (name == "Window Size") {
        setWindowSize(32 << value);
    } else if (name == "Window Increment") {
        setWindowHopLevel(value);
    } else if (name == "Oversampling") {
        setOversampling(1 << value);
    } else if (name == "Min Frequency") {
        switch (value) {
        default:
        case 0: setMinFrequency(0); break;
        case 1: setMinFrequency(10); break;
        case 2: setMinFrequency(20); break;
        case 3: setMinFrequency(40); break;
        case 4: setMinFrequency(100); break;
        case 5: setMinFrequency(250); break;
        case 6: setMinFrequency(500); break;
        case 7: setMinFrequency(1000); break;
        case 8: setMinFrequency(4000); break;
        case 9: setMinFrequency(10000); break;
        }
        int vs = getCurrentVerticalZoomStep();
        if (vs != m_lastEmittedZoomStep) {
            emit verticalZoomChanged();
            m_lastEmittedZoomStep = vs;
        }
    } else if (name == "Max Frequency") {
        switch (value) {
        case 0: setMaxFrequency(500); break;
        case 1: setMaxFrequency(1000); break;
        case 2: setMaxFrequency(1500); break;
        case 3: setMaxFrequency(2000); break;
        case 4: setMaxFrequency(4000); break;
        case 5: setMaxFrequency(6000); break;
        case 6: setMaxFrequency(8000); break;
        case 7: setMaxFrequency(12000); break;
        case 8: setMaxFrequency(16000); break;
        default:
        case 9: setMaxFrequency(0); break;
        }
        int vs = getCurrentVerticalZoomStep();
        if (vs != m_lastEmittedZoomStep) {
            emit verticalZoomChanged();
            m_lastEmittedZoomStep = vs;
        }
    } else if (name == "Colour Scale") {
        setColourScaleMultiple(1.0);
        switch (value) {
        default:
        case 0: setColourScale(ColourScaleType::Linear); break;
        case 1: setColourScale(ColourScaleType::Meter); break;
        case 2:
            setColourScale(ColourScaleType::Log);
            setColourScaleMultiple(2.0);
            break;
        case 3: setColourScale(ColourScaleType::Log); break;
        case 4: setColourScale(ColourScaleType::Phase); break;
        }
    } else if (name == "Frequency Scale") {
        switch (value) {
        default:
        case 0: setBinScale(BinScale::Linear); break;
        case 1: setBinScale(BinScale::Log); break;
        }
    } else if (name == "Bin Display") {
        switch (value) {
        default:
        case 0: setBinDisplay(BinDisplay::AllBins); break;
        case 1: setBinDisplay(BinDisplay::PeakBins); break;
        case 2: setBinDisplay(BinDisplay::PeakFrequencies); break;
        }
    } else if (name == "Normalization") {
        auto n = convertToColumnNorm(value);
        setNormalization(n.first);
        setNormalizeVisibleArea(n.second);
    }
}

void
SpectrogramLayer::invalidateRenderers()
{
#ifdef DEBUG_SPECTROGRAM
    cerr << "SpectrogramLayer::invalidateRenderers called" << endl;
#endif

    for (ViewRendererMap::iterator i = m_renderers.begin();
         i != m_renderers.end(); ++i) {
        delete i->second;
    }
    m_renderers.clear();
}

void
SpectrogramLayer::preferenceChanged(PropertyContainer::PropertyName name)
{
    SVDEBUG << "SpectrogramLayer::preferenceChanged(" << name << ")" << endl;

    if (name == "Window Type") {
        setWindowType(Preferences::getInstance()->getWindowType());
        return;
    }
    if (name == "Spectrogram Y Smoothing") {
        invalidateRenderers();
        invalidateMagnitudes();
        emit layerParametersChanged();
    }
    if (name == "Spectrogram X Smoothing") {
        invalidateRenderers();
        invalidateMagnitudes();
        emit layerParametersChanged();
    }
    if (name == "Tuning Frequency") {
        emit layerParametersChanged();
    }
}

void
SpectrogramLayer::setChannel(int ch)
{
    if (m_channel == ch) return;

    invalidateRenderers();
    m_channel = ch;
    recreateFFTModel();

    emit layerParametersChanged();
}

int
SpectrogramLayer::getChannel() const
{
    return m_channel;
}

int
SpectrogramLayer::getFFTSize() const
{
    return m_windowSize * m_oversampling;
}

void
SpectrogramLayer::setWindowSize(int ws)
{
    if (m_windowSize == ws) return;
    invalidateRenderers();
    m_windowSize = ws;
    recreateFFTModel();
    emit layerParametersChanged();
}

int
SpectrogramLayer::getWindowSize() const
{
    return m_windowSize;
}

void
SpectrogramLayer::setWindowHopLevel(int v)
{
    if (m_windowHopLevel == v) return;
    invalidateRenderers();
    m_windowHopLevel = v;
    recreateFFTModel();
    emit layerParametersChanged();
}

int
SpectrogramLayer::getWindowHopLevel() const
{
    return m_windowHopLevel;
}

void
SpectrogramLayer::setOversampling(int oversampling)
{
    if (m_oversampling == oversampling) return;
    invalidateRenderers();
    m_oversampling = oversampling;
    recreateFFTModel();
    emit layerParametersChanged();
}

int
SpectrogramLayer::getOversampling() const
{
    return m_oversampling;
}

void
SpectrogramLayer::setWindowType(WindowType w)
{
    if (m_windowType == w) return;

    invalidateRenderers();
    
    m_windowType = w;

    recreateFFTModel();

    emit layerParametersChanged();
}

WindowType
SpectrogramLayer::getWindowType() const
{
    return m_windowType;
}

void
SpectrogramLayer::setGain(float gain)
{
//    SVDEBUG << "SpectrogramLayer::setGain(" << gain << ") (my gain is now "
//            << m_gain << ")" << endl;

    if (m_gain == gain) return;

    invalidateRenderers();
    
    m_gain = gain;
    
    emit layerParametersChanged();
}

float
SpectrogramLayer::getGain() const
{
    return m_gain;
}

void
SpectrogramLayer::setThreshold(float threshold)
{
    if (m_threshold == threshold) return;

    invalidateRenderers();
    
    m_threshold = threshold;

    emit layerParametersChanged();
}

float
SpectrogramLayer::getThreshold() const
{
    return m_threshold;
}

void
SpectrogramLayer::setMinFrequency(int mf)
{
    if (m_minFrequency == mf) return;

    if (m_verticallyFixed) {
        throw std::logic_error("setMinFrequency called with value differing from the default, on SpectrogramLayer with verticallyFixed true");
    }

//    SVDEBUG << "SpectrogramLayer::setMinFrequency: " << mf << endl;

    invalidateRenderers();
    invalidateMagnitudes();
    
    m_minFrequency = mf;

    emit layerParametersChanged();
}

int
SpectrogramLayer::getMinFrequency() const
{
    return m_minFrequency;
}

void
SpectrogramLayer::setMaxFrequency(int mf)
{
    if (m_maxFrequency == mf) return;

    if (m_verticallyFixed) {
        throw std::logic_error("setMaxFrequency called with value differing from the default, on SpectrogramLayer with verticallyFixed true");
    }
    
//    SVDEBUG << "SpectrogramLayer::setMaxFrequency: " << mf << endl;

    invalidateRenderers();
    invalidateMagnitudes();
    
    m_maxFrequency = mf;
    
    emit layerParametersChanged();
}

int
SpectrogramLayer::getMaxFrequency() const
{
    return m_maxFrequency;
}

void
SpectrogramLayer::setColourRotation(int r)
{
    if (r < 0) r = 0;
    if (r > 256) r = 256;
    int distance = r - m_colourRotation;

    if (distance != 0) {
        m_colourRotation = r;
    }

    // Initially the idea with colour rotation was that we would just
    // rotate the palette of an already-generated cache. That's not
    // really practical now that cacheing is handled in a separate
    // class in which the main cache no longer has a palette.
    invalidateRenderers();
    
    emit layerParametersChanged();
}

void
SpectrogramLayer::setColourScale(ColourScaleType colourScale)
{
    if (m_colourScale == colourScale) return;

    invalidateRenderers();
    
    m_colourScale = colourScale;
    
    emit layerParametersChanged();
}

ColourScaleType
SpectrogramLayer::getColourScale() const
{
    return m_colourScale;
}

void
SpectrogramLayer::setColourScaleMultiple(double multiple)
{
    if (m_colourScaleMultiple == multiple) return;

    invalidateRenderers();
    
    m_colourScaleMultiple = multiple;
    
    emit layerParametersChanged();
}

double
SpectrogramLayer::getColourScaleMultiple() const
{
    return m_colourScaleMultiple;
}

void
SpectrogramLayer::setColourMap(int map)
{
    if (m_colourMap == map) return;

    invalidateRenderers();
    
    m_colourMap = map;

    emit layerParametersChanged();
}

int
SpectrogramLayer::getColourMap() const
{
    return m_colourMap;
}

void
SpectrogramLayer::setBinScale(BinScale binScale)
{
    if (m_binScale == binScale) return;

    invalidateRenderers();
    m_binScale = binScale;

    emit layerParametersChanged();
}

BinScale
SpectrogramLayer::getBinScale() const
{
    return m_binScale;
}

void
SpectrogramLayer::setBinDisplay(BinDisplay binDisplay)
{
    if (m_binDisplay == binDisplay) return;

    invalidateRenderers();
    m_binDisplay = binDisplay;

    emit layerParametersChanged();
}

BinDisplay
SpectrogramLayer::getBinDisplay() const
{
    return m_binDisplay;
}

void
SpectrogramLayer::setNormalization(ColumnNormalization n)
{
    if (m_normalization == n) return;

    invalidateRenderers();
    invalidateMagnitudes();
    m_normalization = n;

    emit layerParametersChanged();
}

ColumnNormalization
SpectrogramLayer::getNormalization() const
{
    return m_normalization;
}

void
SpectrogramLayer::setNormalizeVisibleArea(bool n)
{
    if (m_normalizeVisibleArea == n) return;

    invalidateRenderers();
    invalidateMagnitudes();
    m_normalizeVisibleArea = n;
    
    emit layerParametersChanged();
}

bool
SpectrogramLayer::getNormalizeVisibleArea() const
{
    return m_normalizeVisibleArea;
}

void
SpectrogramLayer::setLayerDormant(const LayerGeometryProvider *v, bool dormant)
{
    if (dormant) {

#ifdef DEBUG_SPECTROGRAM_REPAINT
        cerr << "SpectrogramLayer::setLayerDormant(" << dormant << ")"
                  << endl;
#endif

        if (isLayerDormant(v)) {
            return;
        }

        Layer::setLayerDormant(v, true);

        invalidateRenderers();
        
    } else {

        Layer::setLayerDormant(v, false);
    }
}

bool
SpectrogramLayer::isLayerScrollable(const LayerGeometryProvider *) const
{
    // we do our own cacheing, and don't want to be responsible for
    // guaranteeing to get an invisible seam if someone else scrolls
    // us and we just fill in
    return false;
}

void
SpectrogramLayer::cacheInvalid(ModelId)
{
#ifdef DEBUG_SPECTROGRAM_REPAINT
    cerr << "SpectrogramLayer::cacheInvalid()" << endl;
#endif

    invalidateRenderers();
    invalidateMagnitudes();
}

void
SpectrogramLayer::cacheInvalid(
    ModelId,
#ifdef DEBUG_SPECTROGRAM_REPAINT
    sv_frame_t from, sv_frame_t to
#else 
    sv_frame_t     , sv_frame_t
#endif
    )
{
#ifdef DEBUG_SPECTROGRAM_REPAINT
    cerr << "SpectrogramLayer::cacheInvalid(" << from << ", " << to << ")" << endl;
#endif

    // We used to call invalidateMagnitudes(from, to) to invalidate
    // only those caches whose views contained some of the (from, to)
    // range. That's the right thing to do; it has been lost in
    // pulling out the image cache code, but it might not matter very
    // much, since the underlying models for spectrogram layers don't
    // change very often. Let's see.
    invalidateRenderers();
    invalidateMagnitudes();
}

bool
SpectrogramLayer::hasLightBackground() const 
{
    return ColourMapper(m_colourMap, m_colourInverted, 1.f, 255.f)
        .hasLightBackground();
}

double
SpectrogramLayer::getEffectiveMinFrequency() const
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model) return 0.0;
    
    sv_samplerate_t sr = model->getSampleRate();
    double minf = double(sr) / getFFTSize();

    if (m_minFrequency > 0.0) {
        int minbin = int((double(m_minFrequency) * getFFTSize()) / sr + 0.01);
        if (minbin < 1) minbin = 1;
        minf = minbin * sr / getFFTSize();
    }

    return minf;
}

double
SpectrogramLayer::getEffectiveMaxFrequency() const
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model) return 0.0;
    
    sv_samplerate_t sr = model->getSampleRate();
    double maxf = double(sr) / 2;

    if (m_maxFrequency > 0.0) {
        int maxbin = int((double(m_maxFrequency) * getFFTSize()) / sr + 0.1);
        if (maxbin > getFFTSize() / 2) maxbin = getFFTSize() / 2;
        maxf = maxbin * sr / getFFTSize();
    }

    return maxf;
}

bool
SpectrogramLayer::getYBinRange(LayerGeometryProvider *v, int y, double &q0, double &q1) const
{
    Profiler profiler("SpectrogramLayer::getYBinRange");
    int h = v->getPaintHeight();
    if (y < 0 || y >= h) return false;
    q0 = getBinForY(v, y);
    q1 = getBinForY(v, y-1);
    return true;
}

double
SpectrogramLayer::getYForBin(const LayerGeometryProvider *v, double bin) const
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model) return 0.0;
    
    double minf = getEffectiveMinFrequency();
    double maxf = getEffectiveMaxFrequency();
    bool logarithmic = (m_binScale == BinScale::Log);
    sv_samplerate_t sr = model->getSampleRate();

    double freq = (bin * sr) / getFFTSize();
    
    double y = v->getYForFrequency(freq, minf, maxf, logarithmic);
    
    return y;
}

double
SpectrogramLayer::getBinForY(const LayerGeometryProvider *v, double y) const
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model) return 0.0;

    sv_samplerate_t sr = model->getSampleRate();
    double minf = getEffectiveMinFrequency();
    double maxf = getEffectiveMaxFrequency();

    bool logarithmic = (m_binScale == BinScale::Log);

    double freq = v->getFrequencyForY(y, minf, maxf, logarithmic);

    // Now map on to ("proportion of") actual bins
    double bin = (freq * getFFTSize()) / sr;

    return bin;
}

bool
SpectrogramLayer::getXBinRange(LayerGeometryProvider *v, int x, double &s0, double &s1) const
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model) return false;

    sv_frame_t modelStart = model->getStartFrame();
    sv_frame_t modelEnd = model->getEndFrame();

    // Each pixel column covers an exact range of sample frames:
    sv_frame_t f0 = v->getFrameForX(x) - modelStart;
    sv_frame_t f1 = v->getFrameForX(x + 1) - modelStart - 1;

    if (f1 < int(modelStart) || f0 > int(modelEnd)) {
        return false;
    }
      
    // And that range may be drawn from a possibly non-integral
    // range of spectrogram windows:

    int windowIncrement = getWindowIncrement();
    s0 = double(f0) / windowIncrement;
    s1 = double(f1) / windowIncrement;

    return true;
}
 
bool
SpectrogramLayer::getXBinSourceRange(LayerGeometryProvider *v, int x, RealTime &min, RealTime &max) const
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model) return false;

    double s0 = 0, s1 = 0;
    if (!getXBinRange(v, x, s0, s1)) return false;
    
    int s0i = int(s0 + 0.001);
    int s1i = int(s1);

    int windowIncrement = getWindowIncrement();
    int w0 = s0i * windowIncrement - (m_windowSize - windowIncrement)/2;
    int w1 = s1i * windowIncrement + windowIncrement +
        (m_windowSize - windowIncrement)/2 - 1;
    
    min = RealTime::frame2RealTime(w0, model->getSampleRate());
    max = RealTime::frame2RealTime(w1, model->getSampleRate());
    return true;
}

bool
SpectrogramLayer::getYBinSourceRange(LayerGeometryProvider *v, int y, double &freqMin, double &freqMax)
const
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model) return false;

    double q0 = 0, q1 = 0;
    if (!getYBinRange(v, y, q0, q1)) return false;

    int q0i = int(q0 + 0.001);
    int q1i = int(q1);

    sv_samplerate_t sr = model->getSampleRate();

    for (int q = q0i; q <= q1i; ++q) {
        if (q == q0i) freqMin = (sr * q) / getFFTSize();
        if (q == q1i) freqMax = (sr * (q+1)) / getFFTSize();
    }
    return true;
}

bool
SpectrogramLayer::getAdjustedYBinSourceRange(LayerGeometryProvider *v, int x, int y,
                                             double &freqMin, double &freqMax,
                                             double &adjFreqMin, double &adjFreqMax)
const
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model || !model->isOK() || !model->isReady()) {
        return false;
    }

    auto fft = ModelById::getAs<FFTModel>(m_fftModel);
    if (!fft) return false;

    double s0 = 0, s1 = 0;
    if (!getXBinRange(v, x, s0, s1)) return false;

    double q0 = 0, q1 = 0;
    if (!getYBinRange(v, y, q0, q1)) return false;

    int s0i = int(s0 + 0.001);
    int s1i = int(s1);

    int q0i = int(q0 + 0.001);
    int q1i = int(q1);

    sv_samplerate_t sr = model->getSampleRate();

    bool haveAdj = false;

    bool peaksOnly = (m_binDisplay == BinDisplay::PeakBins ||
                      m_binDisplay == BinDisplay::PeakFrequencies);

    for (int q = q0i; q <= q1i; ++q) {

        for (int s = s0i; s <= s1i; ++s) {

            double binfreq = (double(sr) * q) / getFFTSize();
            if (q == q0i) freqMin = binfreq;
            if (q == q1i) freqMax = binfreq;

            if (peaksOnly && !fft->isLocalPeak(s, q)) continue;

            if (!fft->isOverThreshold
                (s, q, float(m_threshold * double(getFFTSize())/2.0))) {
                continue;
            }

            double freq = binfreq;
            
            if (s < int(fft->getWidth()) - 1) {

                fft->estimateStableFrequency(s, q, freq);
            
                if (!haveAdj || freq < adjFreqMin) adjFreqMin = freq;
                if (!haveAdj || freq > adjFreqMax) adjFreqMax = freq;

                haveAdj = true;
            }
        }
    }

    if (!haveAdj) {
        adjFreqMin = adjFreqMax = 0.0;
    }

    return haveAdj;
}
    
bool
SpectrogramLayer::getXYBinSourceRange(LayerGeometryProvider *v, int x, int y,
                                      double &min, double &max,
                                      double &phaseMin, double &phaseMax) const
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model || !model->isOK() || !model->isReady()) {
        return false;
    }

    double q0 = 0, q1 = 0;
    if (!getYBinRange(v, y, q0, q1)) return false;

    double s0 = 0, s1 = 0;
    if (!getXBinRange(v, x, s0, s1)) return false;
    
    int q0i = int(q0 + 0.001);
    int q1i = int(q1);

    int s0i = int(s0 + 0.001);
    int s1i = int(s1);

    bool rv = false;

    auto fft = ModelById::getAs<FFTModel>(m_fftModel);

    if (fft) {

        int cw = fft->getWidth();
        int ch = fft->getHeight();

        min = 0.0;
        max = 0.0;
        phaseMin = 0.0;
        phaseMax = 0.0;
        bool have = false;

        for (int q = q0i; q <= q1i; ++q) {
            for (int s = s0i; s <= s1i; ++s) {
                if (s >= 0 && q >= 0 && s < cw && q < ch) {

                    double value;

                    value = fft->getPhaseAt(s, q);
                    if (!have || value < phaseMin) { phaseMin = value; }
                    if (!have || value > phaseMax) { phaseMax = value; }

                    value = fft->getMagnitudeAt(s, q) / (getFFTSize()/2.0);
                    if (!have || value < min) { min = value; }
                    if (!have || value > max) { max = value; }
                    
                    have = true;
                }       
            }
        }
        
        if (have) {
            rv = true;
        }
    }

    return rv;
}
        
void
SpectrogramLayer::recreateFFTModel()
{
    SVDEBUG << "SpectrogramLayer::recreateFFTModel called" << endl;

    { // scope, avoid hanging on to this pointer
        auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
        if (!model || !model->isOK()) {
            deleteDerivedModels();
            return;
        }
    }
    
    deleteDerivedModels();

    auto newFFTModel = std::make_shared<FFTModel>(m_model,
                                                  m_channel,
                                                  m_windowType,
                                                  m_windowSize,
                                                  getWindowIncrement(),
                                                  getFFTSize());

    if (!newFFTModel->isOK()) {
        QMessageBox::critical
            (nullptr, tr("FFT cache failed"),
             tr("Failed to create the FFT model for this spectrogram.\n"
                "There may be insufficient memory or disc space to continue."));
        return;
    }

    if (m_verticallyFixed) {
        newFFTModel->setMaximumFrequency(getMaxFrequency());
    }
    
    m_fftModel = ModelById::add(newFFTModel);

    bool createWholeCache = false;
    checkCacheSpace(&m_peakCacheDivisor, &createWholeCache);
    
    if (createWholeCache) {

        auto whole = std::make_shared<Dense3DModelPeakCache>(m_fftModel, 1);
        m_wholeCache = ModelById::add(whole);

        auto peaks = std::make_shared<Dense3DModelPeakCache>(m_fftModel,
                                                             m_peakCacheDivisor);
        m_peakCache = ModelById::add(peaks);

    } else {

        auto peaks = std::make_shared<Dense3DModelPeakCache>(m_fftModel,
                                                             m_peakCacheDivisor);
        m_peakCache = ModelById::add(peaks);
    }
}

void
SpectrogramLayer::checkCacheSpace(int *suggestedPeakDivisor,
                                  bool *createWholeCache) const
{
    *suggestedPeakDivisor = 8;
    *createWholeCache = false;

    auto fftModel = ModelById::getAs<FFTModel>(m_fftModel);
    if (!fftModel) return;

    size_t sz =
        size_t(fftModel->getWidth()) *
        size_t(fftModel->getHeight()) *
        sizeof(float);

    try {
        SVDEBUG << "Requesting advice from StorageAdviser on whether to create whole-model cache" << endl;
        // The lower amount here is the amount required for the
        // slightly higher-resolution version of the peak cache
        // without a whole-model cache; the higher amount is that for
        // the whole-model cache. The factors of 1024 are because
        // StorageAdviser rather stupidly works in kilobytes
        StorageAdviser::Recommendation recommendation =
            StorageAdviser::recommend
            (StorageAdviser::Criteria(StorageAdviser::SpeedCritical |
                                      StorageAdviser::PrecisionCritical |
                                      StorageAdviser::FrequentLookupLikely),
             (sz / 8) / 1024, sz / 1024);
        if (recommendation & StorageAdviser::UseDisc) {
            SVDEBUG << "Seems inadvisable to create whole-model cache" << endl;
        } else if (recommendation & StorageAdviser::ConserveSpace) {
            SVDEBUG << "Seems inadvisable to create whole-model cache but acceptable to use the slightly higher-resolution peak cache" << endl;
            *suggestedPeakDivisor = 4;
        } else  {
            SVDEBUG << "Seems fine to create whole-model cache" << endl;
            *createWholeCache = true;
        }
    } catch (const InsufficientDiscSpace &) {
        SVDEBUG << "Seems like a terrible idea to create whole-model cache" << endl;
    }
}

ModelId
SpectrogramLayer::getSliceableModel() const
{
    return m_fftModel;
}

void
SpectrogramLayer::invalidateMagnitudes()
{
#ifdef DEBUG_SPECTROGRAM
    cerr << "SpectrogramLayer::invalidateMagnitudes called" << endl;
#endif
    m_viewMags.clear();
}

void
SpectrogramLayer::setSynchronousPainting(bool synchronous)
{
    m_synchronous = synchronous;
}

Colour3DPlotRenderer *
SpectrogramLayer::getRenderer(LayerGeometryProvider *v) const
{
    int viewId = v->getId();
    
    if (m_renderers.find(viewId) == m_renderers.end()) {

        Colour3DPlotRenderer::Sources sources;
        sources.verticalBinLayer = this;
        sources.fft = m_fftModel;
        sources.source = sources.fft;
        if (!m_peakCache.isNone()) sources.peakCaches.push_back(m_peakCache);
        if (!m_wholeCache.isNone()) sources.peakCaches.push_back(m_wholeCache);

        ColourScale::Parameters cparams;
        cparams.colourMap = m_colourMap;
        cparams.scaleType = m_colourScale;
        cparams.multiple = m_colourScaleMultiple;

        if (m_colourScale != ColourScaleType::Phase) {
            cparams.gain = m_gain;
            cparams.threshold = m_threshold;
        }

        double minValue = 0.0f;
        double maxValue = 1.0f;
        
        if (m_normalizeVisibleArea && m_viewMags[viewId].isSet()) {
            minValue = m_viewMags[viewId].getMin();
            maxValue = m_viewMags[viewId].getMax();
        } else if (m_colourScale == ColourScaleType::Linear &&
                   m_normalization == ColumnNormalization::None) {
            maxValue = 0.1f;
        }

        if (maxValue <= minValue) {
            maxValue = minValue + 0.1f;
        }
        if (maxValue <= m_threshold) {
            maxValue = m_threshold + 0.1f;
        }

        cparams.minValue = minValue;
        cparams.maxValue = maxValue;

        m_lastRenderedMags[viewId] = MagnitudeRange(float(minValue),
                                                    float(maxValue));

        Colour3DPlotRenderer::Parameters params;
        params.colourScale = ColourScale(cparams);
        params.normalization = m_normalization;
        params.binDisplay = m_binDisplay;
        params.binScale = m_binScale;
        params.alwaysOpaque = true;
        params.invertVertical = false;
        params.scaleFactor = 1.0;
        params.colourRotation = m_colourRotation;

        if (m_colourScale != ColourScaleType::Phase &&
            m_normalization != ColumnNormalization::Hybrid) {
            params.scaleFactor *= 2.f / float(getWindowSize());
        }

        Preferences::SpectrogramSmoothing smoothing = 
            Preferences::getInstance()->getSpectrogramSmoothing();
        params.interpolate = 
            (smoothing != Preferences::NoSpectrogramSmoothing);

        m_renderers[viewId] = new Colour3DPlotRenderer(sources, params);

        m_crosshairColour =
            ColourMapper(m_colourMap, m_colourInverted, 1.f, 255.f)
            .getContrastingColour();
    }

    return m_renderers[viewId];
}

void
SpectrogramLayer::paintWithRenderer(LayerGeometryProvider *v, QPainter &paint, QRect rect) const
{
    Colour3DPlotRenderer *renderer = getRenderer(v);

    Colour3DPlotRenderer::RenderResult result;
    MagnitudeRange magRange;
    int viewId = v->getId();

    bool continuingPaint = !renderer->geometryChanged(v);
    
    if (continuingPaint) {
        magRange = m_viewMags[viewId];
    }
    
    if (m_synchronous) {

        result = renderer->render(v, paint, rect);

    } else {

        result = renderer->renderTimeConstrained(v, paint, rect);

#ifdef DEBUG_SPECTROGRAM_REPAINT
        cerr << "rect width from this paint: " << result.rendered.width()
             << ", mag range in this paint: " << result.range.getMin() << " -> "
             << result.range.getMax() << endl;
#endif
        
        QRect uncached = renderer->getLargestUncachedRect(v);
        if (uncached.width() > 0) {
            v->updatePaintRect(uncached);
        }
    }

    magRange.sample(result.range);

    if (magRange.isSet()) {
        if (m_viewMags[viewId] != magRange) {
            m_viewMags[viewId] = magRange;
#ifdef DEBUG_SPECTROGRAM_REPAINT
            cerr << "mag range in this view has changed: "
                 << magRange.getMin() << " -> " << magRange.getMax() << endl;
#endif
        }
    }

    if (!continuingPaint && m_normalizeVisibleArea &&
        m_viewMags[viewId] != m_lastRenderedMags[viewId]) {
#ifdef DEBUG_SPECTROGRAM_REPAINT
        cerr << "mag range has changed from last rendered range: re-rendering"
             << endl;
#endif
        delete m_renderers[viewId];
        m_renderers.erase(viewId);
        v->updatePaintRect(v->getPaintRect());
    }
}

void
SpectrogramLayer::paint(LayerGeometryProvider *v, QPainter &paint, QRect rect) const
{
    Profiler profiler("SpectrogramLayer::paint", false);

#ifdef DEBUG_SPECTROGRAM_REPAINT
    cerr << "SpectrogramLayer::paint() entering: m_model is " << m_model << ", zoom level is " << v->getZoomLevel() << endl;
    
    cerr << "SpectrogramLayer::paint(): rect is " << rect.x() << "," << rect.y() << " " << rect.width() << "x" << rect.height() << endl;
#endif

    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model || !model->isOK() || !model->isReady()) {
        return;
    }

    paintWithRenderer(v, paint, rect);

    illuminateLocalFeatures(v, paint);
}

void
SpectrogramLayer::illuminateLocalFeatures(LayerGeometryProvider *v, QPainter &paint) const
{
    Profiler profiler("SpectrogramLayer::illuminateLocalFeatures");

    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    
    QPoint localPos;
    if (!v->shouldIlluminateLocalFeatures(this, localPos) || !model) {
        return;
    }

#ifdef DEBUG_SPECTROGRAM_REPAINT
    cerr << "SpectrogramLayer: illuminateLocalFeatures("
              << localPos.x() << "," << localPos.y() << ")" << endl;
#endif

    double s0, s1;
    double f0, f1;

    if (getXBinRange(v, localPos.x(), s0, s1) &&
        getYBinSourceRange(v, localPos.y(), f0, f1)) {
        
        int s0i = int(s0 + 0.001);
        int s1i = int(s1);
        
        int x0 = v->getXForFrame(s0i * getWindowIncrement());
        int x1 = v->getXForFrame((s1i + 1) * getWindowIncrement());

        int y1 = int(getYForFrequency(v, f1));
        int y0 = int(getYForFrequency(v, f0));
        
#ifdef DEBUG_SPECTROGRAM_REPAINT
        cerr << "SpectrogramLayer: illuminate "
                  << x0 << "," << y1 << " -> " << x1 << "," << y0 << endl;
#endif
        
        paint.setPen(v->getForeground());

        //!!! should we be using paintCrosshairs for this?

        paint.drawRect(x0, y1, x1 - x0 + 1, y0 - y1 + 1);
    }
}

double
SpectrogramLayer::getYForFrequency(const LayerGeometryProvider *v, double frequency) const
{
    return v->getYForFrequency(frequency,
                               getEffectiveMinFrequency(),
                               getEffectiveMaxFrequency(),
                               m_binScale == BinScale::Log);
}

double
SpectrogramLayer::getFrequencyForY(const LayerGeometryProvider *v, int y) const
{
    return v->getFrequencyForY(y,
                               getEffectiveMinFrequency(),
                               getEffectiveMaxFrequency(),
                               m_binScale == BinScale::Log);
}

int
SpectrogramLayer::getCompletion(LayerGeometryProvider *) const
{
    auto fftModel = ModelById::getAs<FFTModel>(m_fftModel);
    if (!fftModel) return 100;
    int completion = fftModel->getCompletion();
#ifdef DEBUG_SPECTROGRAM_REPAINT
    cerr << "SpectrogramLayer::getCompletion: completion = " << completion << endl;
#endif
    return completion;
}

QString
SpectrogramLayer::getError(LayerGeometryProvider *) const
{
    auto fftModel = ModelById::getAs<FFTModel>(m_fftModel);
    if (!fftModel) return "";
    return fftModel->getError();
}

bool
SpectrogramLayer::getValueExtents(double &min, double &max,
                                  bool &logarithmic, QString &unit) const
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model) return false;

    sv_samplerate_t sr = model->getSampleRate();
    min = double(sr) / getFFTSize();
    max = double(sr) / 2;
    
    logarithmic = (m_binScale == BinScale::Log);
    unit = "Hz";
    return true;
}

bool
SpectrogramLayer::getDisplayExtents(double &min, double &max) const
{
    min = getEffectiveMinFrequency();
    max = getEffectiveMaxFrequency();

//    SVDEBUG << "SpectrogramLayer::getDisplayExtents: " << min << "->" << max << endl;
    return true;
}    

bool
SpectrogramLayer::setDisplayExtents(double min, double max)
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model) return false;

//    SVDEBUG << "SpectrogramLayer::setDisplayExtents: " << min << "->" << max << endl;

    if (min < 0) min = 0;
    if (max > model->getSampleRate()/2.0) max = model->getSampleRate()/2.0;
    
    int minf = int(lrint(min));
    int maxf = int(lrint(max));

    if (m_minFrequency == minf && m_maxFrequency == maxf) return true;

    invalidateRenderers();
    invalidateMagnitudes();

    if (m_verticallyFixed &&
        (m_minFrequency != minf || m_maxFrequency != maxf)) {
        throw std::logic_error("setDisplayExtents called with values differing from the defaults, on SpectrogramLayer with verticallyFixed true");
    }

    m_minFrequency = minf;
    m_maxFrequency = maxf;
    
    emit layerParametersChanged();

    int vs = getCurrentVerticalZoomStep();
    if (vs != m_lastEmittedZoomStep) {
        emit verticalZoomChanged();
        m_lastEmittedZoomStep = vs;
    }

    return true;
}

bool
SpectrogramLayer::getYScaleValue(const LayerGeometryProvider *v, int y,
                                 double &value, QString &unit) const
{
    value = getFrequencyForY(v, y);
    unit = "Hz";
    return true;
}

bool
SpectrogramLayer::snapToFeatureFrame(LayerGeometryProvider *,
                                     sv_frame_t &frame,
                                     int &resolution,
                                     SnapType snap) const
{
    resolution = getWindowIncrement();
    sv_frame_t left = (frame / resolution) * resolution;
    sv_frame_t right = left + resolution;

    switch (snap) {
    case SnapLeft:  frame = left;  break;
    case SnapRight: frame = right; break;
    case SnapNeighbouring:
        if (frame - left > right - frame) frame = right;
        else frame = left;
        break;
    }
    
    return true;
} 

void
SpectrogramLayer::measureDoubleClick(LayerGeometryProvider *v, QMouseEvent *e)
{
    const Colour3DPlotRenderer *renderer = getRenderer(v);
    if (!renderer) return;

    QRect rect = renderer->findSimilarRegionExtents(e->pos());
    if (rect.isValid()) {
        MeasureRect mr;
        setMeasureRectFromPixrect(v, mr, rect);
        CommandHistory::getInstance()->addCommand
            (new AddMeasurementRectCommand(this, mr));
    }
}

bool
SpectrogramLayer::getCrosshairExtents(LayerGeometryProvider *v, QPainter &paint,
                                      QPoint cursorPos,
                                      vector<QRect> &extents) const
{
    // Qt 5.13 deprecates QFontMetrics::width(), but its suggested
    // replacement (horizontalAdvance) was only added in Qt 5.11
    // which is too new for us
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"

    QRect vertical(cursorPos.x() - 12, 0, 12, v->getPaintHeight());
    extents.push_back(vertical);

    QRect horizontal(0, cursorPos.y(), cursorPos.x(), 1);
    extents.push_back(horizontal);

    int sw = getVerticalScaleWidth(v, m_haveDetailedScale, paint);

    QRect freq(sw, cursorPos.y() - paint.fontMetrics().ascent() - 2,
               paint.fontMetrics().width("123456 Hz") + 2,
               paint.fontMetrics().height());
    extents.push_back(freq);

    QRect pitch(sw, cursorPos.y() + 2,
                paint.fontMetrics().width("C#10+50c") + 2,
                paint.fontMetrics().height());
    extents.push_back(pitch);

    QRect rt(cursorPos.x(),
             v->getPaintHeight() - paint.fontMetrics().height() - 2,
             paint.fontMetrics().width("1234.567 s"),
             paint.fontMetrics().height());
    extents.push_back(rt);

    int w(paint.fontMetrics().width("1234567890") + 2);
    QRect frame(cursorPos.x() - w - 2,
                v->getPaintHeight() - paint.fontMetrics().height() - 2,
                w,
                paint.fontMetrics().height());
    extents.push_back(frame);

    return true;
}

void
SpectrogramLayer::paintCrosshairs(LayerGeometryProvider *v, QPainter &paint,
                                  QPoint cursorPos) const
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model) return;

    paint.save();
    
    int sw = getVerticalScaleWidth(v, m_haveDetailedScale, paint);

    QFont fn = paint.font();
    if (fn.pointSize() > 8) {
        fn.setPointSize(fn.pointSize() - 1);
        paint.setFont(fn);
    }
    paint.setPen(m_crosshairColour);

    paint.drawLine(0, cursorPos.y(), cursorPos.x() - 1, cursorPos.y());
    paint.drawLine(cursorPos.x(), 0, cursorPos.x(), v->getPaintHeight());
    
    double fundamental = getFrequencyForY(v, cursorPos.y());

    PaintAssistant::drawVisibleText
        (v, paint,
         sw + 2,
         cursorPos.y() - 2,
         QString("%1 Hz").arg(fundamental),
         PaintAssistant::OutlinedText);

    if (Pitch::isFrequencyInMidiRange(fundamental)) {
        QString pitchLabel = Pitch::getPitchLabelForFrequency(fundamental);
        PaintAssistant::drawVisibleText
            (v, paint,
             sw + 2,
             cursorPos.y() + paint.fontMetrics().ascent() + 2,
             pitchLabel,
             PaintAssistant::OutlinedText);
    }

    sv_frame_t frame = v->getFrameForX(cursorPos.x());
    RealTime rt = RealTime::frame2RealTime(frame, model->getSampleRate());
    QString rtLabel = QString("%1 s").arg(rt.toText(true).c_str());
    QString frameLabel = QString("%1").arg(frame);
    PaintAssistant::drawVisibleText
        (v, paint,
         cursorPos.x() - paint.fontMetrics().width(frameLabel) - 2,
         v->getPaintHeight() - 2,
         frameLabel,
         PaintAssistant::OutlinedText);
    PaintAssistant::drawVisibleText
        (v, paint,
         cursorPos.x() + 2,
         v->getPaintHeight() - 2,
         rtLabel,
         PaintAssistant::OutlinedText);

    int harmonic = 2;

    while (harmonic < 100) {

        int hy = int(lrint(getYForFrequency(v, fundamental * harmonic)));
        if (hy < 0 || hy > v->getPaintHeight()) break;
        
        int len = 7;

        if (harmonic % 2 == 0) {
            if (harmonic % 4 == 0) {
                len = 12;
            } else {
                len = 10;
            }
        }

        paint.drawLine(cursorPos.x() - len,
                       hy,
                       cursorPos.x(),
                       hy);

        ++harmonic;
    }

    paint.restore();
}

QString
SpectrogramLayer::getFeatureDescription(LayerGeometryProvider *v, QPoint &pos) const
{
    int x = pos.x();
    int y = pos.y();

    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model || !model->isOK()) return "";

    double magMin = 0, magMax = 0;
    double phaseMin = 0, phaseMax = 0;
    double freqMin = 0, freqMax = 0;
    double adjFreqMin = 0, adjFreqMax = 0;
    QString pitchMin, pitchMax;
    RealTime rtMin, rtMax;

    bool haveValues = false;

    if (!getXBinSourceRange(v, x, rtMin, rtMax)) {
        return "";
    }
    if (getXYBinSourceRange(v, x, y, magMin, magMax, phaseMin, phaseMax)) {
        haveValues = true;
    }

    QString adjFreqText = "", adjPitchText = "";

    if (m_binDisplay == BinDisplay::PeakFrequencies) {

        if (!getAdjustedYBinSourceRange(v, x, y, freqMin, freqMax,
                                        adjFreqMin, adjFreqMax)) {
            return "";
        }

        if (adjFreqMin != adjFreqMax) {
            adjFreqText = tr("Peak Frequency:\t%1 - %2 Hz\n")
                .arg(adjFreqMin).arg(adjFreqMax);
        } else {
            adjFreqText = tr("Peak Frequency:\t%1 Hz\n")
                .arg(adjFreqMin);
        }

        QString pmin = Pitch::getPitchLabelForFrequency(adjFreqMin);
        QString pmax = Pitch::getPitchLabelForFrequency(adjFreqMax);

        if (pmin != pmax) {
            adjPitchText = tr("Peak Pitch:\t%3 - %4\n").arg(pmin).arg(pmax);
        } else {
            adjPitchText = tr("Peak Pitch:\t%2\n").arg(pmin);
        }

    } else {
        
        if (!getYBinSourceRange(v, y, freqMin, freqMax)) return "";
    }

    QString text;

    if (rtMin != rtMax) {
        text += tr("Time:\t%1 - %2\n")
            .arg(rtMin.toText(true).c_str())
            .arg(rtMax.toText(true).c_str());
    } else {
        text += tr("Time:\t%1\n")
            .arg(rtMin.toText(true).c_str());
    }

    if (freqMin != freqMax) {
        text += tr("%1Bin Frequency:\t%2 - %3 Hz\n%4Bin Pitch:\t%5 - %6\n")
            .arg(adjFreqText)
            .arg(freqMin)
            .arg(freqMax)
            .arg(adjPitchText)
            .arg(Pitch::getPitchLabelForFrequency(freqMin))
            .arg(Pitch::getPitchLabelForFrequency(freqMax));
    } else {
        text += tr("%1Bin Frequency:\t%2 Hz\n%3Bin Pitch:\t%4\n")
            .arg(adjFreqText)
            .arg(freqMin)
            .arg(adjPitchText)
            .arg(Pitch::getPitchLabelForFrequency(freqMin));
    }   

    if (haveValues) {
        double dbMin = AudioLevel::multiplier_to_dB(magMin);
        double dbMax = AudioLevel::multiplier_to_dB(magMax);
        QString dbMinString;
        QString dbMaxString;
        if (dbMin == AudioLevel::DB_FLOOR) {
            dbMinString = Strings::minus_infinity;
        } else {
            dbMinString = QString("%1").arg(lrint(dbMin));
        }
        if (dbMax == AudioLevel::DB_FLOOR) {
            dbMaxString = Strings::minus_infinity;
        } else {
            dbMaxString = QString("%1").arg(lrint(dbMax));
        }
        if (lrint(dbMin) != lrint(dbMax)) {
            text += tr("dB:\t%1 - %2").arg(dbMinString).arg(dbMaxString);
        } else {
            text += tr("dB:\t%1").arg(dbMinString);
        }
        if (phaseMin != phaseMax) {
            text += tr("\nPhase:\t%1 - %2").arg(phaseMin).arg(phaseMax);
        } else {
            text += tr("\nPhase:\t%1").arg(phaseMin);
        }
    }

    return text;
}

int
SpectrogramLayer::getColourScaleWidth(QPainter &paint) const
{
    int cw;

    cw = paint.fontMetrics().width("-80dB");

    return cw;
}

int
SpectrogramLayer::getVerticalScaleWidth(LayerGeometryProvider *, bool detailed, QPainter &paint) const
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model || !model->isOK()) return 0;

    int cw = 0;
    if (detailed) cw = getColourScaleWidth(paint);

    int tw = paint.fontMetrics().width(QString("%1")
                                     .arg(m_maxFrequency > 0 ?
                                          m_maxFrequency - 1 :
                                          model->getSampleRate() / 2));

    int fw = paint.fontMetrics().width(tr("43Hz"));
    if (tw < fw) tw = fw;

    int tickw = (m_binScale == BinScale::Log ? 10 : 4);
    
    return cw + tickw + tw + 13;
}

void
SpectrogramLayer::paintVerticalScale(LayerGeometryProvider *v, bool detailed,
                                     QPainter &paint, QRect rect) const
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model || !model->isOK()) {
        return;
    }

    Profiler profiler("SpectrogramLayer::paintVerticalScale");

    //!!! cache this?
    
    int h = rect.height(), w = rect.width();
    int textHeight = paint.fontMetrics().height();

    if (detailed && (h > textHeight * 3 + 10)) {
        paintDetailedScale(v, paint, rect);
    }
    m_haveDetailedScale = detailed;

    int tickw = (m_binScale == BinScale::Log ? 10 : 4);
    int pkw = (m_binScale == BinScale::Log ? 10 : 0);

    int bins = getFFTSize() / 2;
    sv_samplerate_t sr = model->getSampleRate();

    if (m_maxFrequency > 0) {
        bins = int((double(m_maxFrequency) * getFFTSize()) / sr + 0.1);
        if (bins > getFFTSize() / 2) bins = getFFTSize() / 2;
    }

    int cw = 0;
    if (detailed) cw = getColourScaleWidth(paint);

    int py = -1;
    int toff = -textHeight + paint.fontMetrics().ascent() + 2;

    paint.drawLine(cw + 7, 0, cw + 7, h);

    int bin = -1;

    for (int y = 0; y < v->getPaintHeight(); ++y) {

        double q0, q1;
        if (!getYBinRange(v, v->getPaintHeight() - y, q0, q1)) continue;

        int vy;

        if (int(q0) > bin) {
            vy = y;
            bin = int(q0);
        } else {
            continue;
        }

        int freq = int((sr * bin) / getFFTSize());

        if (py >= 0 && (vy - py) < textHeight - 1) {
            if (m_binScale == BinScale::Linear) {
                paint.drawLine(w - tickw, h - vy, w, h - vy);
            }
            continue;
        }

        QString text = QString("%1").arg(freq);
        if (bin == 1) text = tr("%1Hz").arg(freq); // bin 0 is DC
        paint.drawLine(cw + 7, h - vy, w - pkw - 1, h - vy);

        if (h - vy - textHeight >= -2) {
            int tx = w - 3 - paint.fontMetrics().width(text) - max(tickw, pkw);
            paint.drawText(tx, h - vy + toff, text);
        }

        py = vy;
    }

    if (m_binScale == BinScale::Log) {

        // piano keyboard

        PianoScale().paintPianoVertical
            (v, paint, QRect(w - pkw - 1, 0, pkw, h),
             getEffectiveMinFrequency(), getEffectiveMaxFrequency());
    }

    m_haveDetailedScale = detailed;
}

void
SpectrogramLayer::paintDetailedScale(LayerGeometryProvider *v,
                                     QPainter &paint, QRect rect) const
{
    // The colour scale

    if (m_colourScale == ColourScaleType::Phase) {
        paintDetailedScalePhase(v, paint, rect);
        return;
    }
    
    int h = rect.height();
    int textHeight = paint.fontMetrics().height();
    int toff = -textHeight + paint.fontMetrics().ascent() + 2;

    int cw = getColourScaleWidth(paint);
    int cbw = paint.fontMetrics().width("dB");

    int topLines = 2;

    int ch = h - textHeight * (topLines + 1) - 8;
//      paint.drawRect(4, textHeight + 4, cw - 1, ch + 1);
    paint.drawRect(4 + cw - cbw, textHeight * topLines + 4, cbw - 1, ch + 1);

    QString top, bottom;
    double min = m_viewMags[v->getId()].getMin();
    double max = m_viewMags[v->getId()].getMax();

    if (min < m_threshold) min = m_threshold;
    if (max <= min) max = min + 0.1;
        
    double dBmin = AudioLevel::multiplier_to_dB(min);
    double dBmax = AudioLevel::multiplier_to_dB(max);

#ifdef DEBUG_SPECTROGRAM_REPAINT
    cerr << "paintVerticalScale: for view id " << v->getId()
         << ": min = " << min << ", max = " << max
         << ", dBmin = " << dBmin << ", dBmax = " << dBmax << endl;
#endif
        
    if (dBmax < -60.f) dBmax = -60.f;
    else top = QString("%1").arg(lrint(dBmax));

    if (dBmin < dBmax - 60.f) dBmin = dBmax - 60.f;
    bottom = QString("%1").arg(lrint(dBmin));

#ifdef DEBUG_SPECTROGRAM_REPAINT
    cerr << "adjusted dB range to min = " << dBmin << ", max = " << dBmax
         << endl;
#endif
        
    paint.drawText((cw + 6 - paint.fontMetrics().width("dBFS")) / 2,
                   2 + textHeight + toff, "dBFS");

    paint.drawText(3 + cw - cbw - paint.fontMetrics().width(top),
                   2 + textHeight * topLines + toff + textHeight/2, top);

    paint.drawText(3 + cw - cbw - paint.fontMetrics().width(bottom),
                   h + toff - 3 - textHeight/2, bottom);

    paint.save();
    paint.setBrush(Qt::NoBrush);

    int lasty = 0;
    int lastdb = 0;

    for (int i = 0; i < ch; ++i) {

        double dBval = dBmin + (((dBmax - dBmin) * i) / (ch - 1));
        int idb = int(dBval);

        double value = AudioLevel::dB_to_multiplier(dBval);
        paint.setPen(getRenderer(v)->getColour(value));

        int y = textHeight * topLines + 4 + ch - i;

        paint.drawLine(5 + cw - cbw, y, cw + 2, y);
        
        if (i == 0) {
            lasty = y;
            lastdb = idb;
        } else if (i < ch - paint.fontMetrics().ascent() &&
                   idb != lastdb &&
                   ((abs(y - lasty) > textHeight && 
                     idb % 10 == 0) ||
                    (abs(y - lasty) > paint.fontMetrics().ascent() && 
                     idb % 5 == 0))) {
            paint.setPen(v->getForeground());
            QString text = QString("%1").arg(idb);
            paint.drawText(3 + cw - cbw - paint.fontMetrics().width(text),
                           y + toff + textHeight/2, text);
            paint.drawLine(5 + cw - cbw, y, 8 + cw - cbw, y);
            lasty = y;
            lastdb = idb;
        }
    }
    paint.restore();
}

void
SpectrogramLayer::paintDetailedScalePhase(LayerGeometryProvider *v,
                                          QPainter &paint, QRect rect) const
{
    // The colour scale in phase mode
    
    int h = rect.height();
    int textHeight = paint.fontMetrics().height();
    int toff = -textHeight + paint.fontMetrics().ascent() + 2;

    int cw = getColourScaleWidth(paint);

    // Phase is not measured in dB of course, but this places the
    // scale at the same position as in the magnitude spectrogram
    int cbw = paint.fontMetrics().width("dB");

    int topLines = 1;

    int ch = h - textHeight * (topLines + 1) - 8;
    paint.drawRect(4 + cw - cbw, textHeight * topLines + 4, cbw - 1, ch + 1);

    QString top = Strings::pi, bottom = Strings::minus_pi, middle = "0";
    
    double min = -M_PI;
    double max =  M_PI;

    paint.drawText(3 + cw - cbw - paint.fontMetrics().width(top),
                   2 + textHeight * topLines + toff + textHeight/2, top);

    paint.drawText(3 + cw - cbw - paint.fontMetrics().width(middle),
                   2 + textHeight * topLines + ch/2 + toff + textHeight/2, middle);

    paint.drawText(3 + cw - cbw - paint.fontMetrics().width(bottom),
                   h + toff - 3 - textHeight/2, bottom);

    paint.save();
    paint.setBrush(Qt::NoBrush);

    for (int i = 0; i < ch; ++i) {
        double val = min + (((max - min) * i) / (ch - 1));
        paint.setPen(getRenderer(v)->getColour(val));
        int y = textHeight * topLines + 4 + ch - i;
        paint.drawLine(5 + cw - cbw, y, cw + 2, y);
    }
    paint.restore();
}

class SpectrogramRangeMapper : public RangeMapper
{
public:
    SpectrogramRangeMapper(sv_samplerate_t sr, int /* fftsize */) :
        m_dist(sr / 2),
        m_s2(sqrt(sqrt(2))) { }
    ~SpectrogramRangeMapper() override { }
    
    int getPositionForValue(double value) const override {

        double dist = m_dist;
    
        int n = 0;

        while (dist > (value + 0.00001) && dist > 0.1) {
            dist /= m_s2;
            ++n;
        }

        return n;
    }
    
    int getPositionForValueUnclamped(double value) const override {
        // We don't really support this
        return getPositionForValue(value);
    }

    double getValueForPosition(int position) const override {

        // Vertical zoom step 0 shows the entire range from DC ->
        // Nyquist frequency.  Step 1 shows 2^(1/4) of the range of
        // step 0, and so on until the visible range is smaller than
        // the frequency step between bins at the current fft size.

        double dist = m_dist;
    
        int n = 0;
        while (n < position) {
            dist /= m_s2;
            ++n;
        }

        return dist;
    }
    
    double getValueForPositionUnclamped(int position) const override {
        // We don't really support this
        return getValueForPosition(position);
    }

    QString getUnit() const override { return "Hz"; }

protected:
    double m_dist;
    double m_s2;
};

int
SpectrogramLayer::getVerticalZoomSteps(int &defaultStep) const
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model) return 0;

    sv_samplerate_t sr = model->getSampleRate();

    SpectrogramRangeMapper mapper(sr, getFFTSize());

//    int maxStep = mapper.getPositionForValue((double(sr) / getFFTSize()) + 0.001);
    int maxStep = mapper.getPositionForValue(0);
    int minStep = mapper.getPositionForValue(double(sr) / 2);

    int initialMax = m_initialMaxFrequency;
    if (initialMax == 0) initialMax = int(sr / 2);

    defaultStep = mapper.getPositionForValue(initialMax) - minStep;

//    SVDEBUG << "SpectrogramLayer::getVerticalZoomSteps: " << maxStep - minStep << " (" << maxStep <<"-" << minStep << "), default is " << defaultStep << " (from initial max freq " << initialMax << ")" << endl;

    return maxStep - minStep;
}

int
SpectrogramLayer::getCurrentVerticalZoomStep() const
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model) return 0;

    double dmin, dmax;
    getDisplayExtents(dmin, dmax);
    
    SpectrogramRangeMapper mapper(model->getSampleRate(), getFFTSize());
    int n = mapper.getPositionForValue(dmax - dmin);
//    SVDEBUG << "SpectrogramLayer::getCurrentVerticalZoomStep: " << n << endl;
    return n;
}

void
SpectrogramLayer::setVerticalZoomStep(int step)
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model) return;

    double dmin = m_minFrequency, dmax = m_maxFrequency;
//    getDisplayExtents(dmin, dmax);

//    cerr << "current range " << dmin << " -> " << dmax << ", range " << dmax-dmin << ", mid " << (dmax + dmin)/2 << endl;
    
    sv_samplerate_t sr = model->getSampleRate();
    SpectrogramRangeMapper mapper(sr, getFFTSize());
    double newdist = mapper.getValueForPosition(step);

    double newmin, newmax;

    if (m_binScale == BinScale::Log) {

        // need to pick newmin and newmax such that
        //
        // (log(newmin) + log(newmax)) / 2 == logmid
        // and
        // newmax - newmin = newdist
        //
        // so log(newmax - newdist) + log(newmax) == 2logmid
        // log(newmax(newmax - newdist)) == 2logmid
        // newmax.newmax - newmax.newdist == exp(2logmid)
        // newmax^2 + (-newdist)newmax + -exp(2logmid) == 0
        // quadratic with a = 1, b = -newdist, c = -exp(2logmid), all known
        // 
        // positive root
        // newmax = (newdist + sqrt(newdist^2 + 4exp(2logmid))) / 2
        //
        // but logmid = (log(dmin) + log(dmax)) / 2
        // so exp(2logmid) = exp(log(dmin) + log(dmax))
        // = exp(log(dmin.dmax))
        // = dmin.dmax
        // so newmax = (newdist + sqrtf(newdist^2 + 4dmin.dmax)) / 2

        newmax = (newdist + sqrt(newdist*newdist + 4*dmin*dmax)) / 2;
        newmin = newmax - newdist;

//        cerr << "newmin = " << newmin << ", newmax = " << newmax << endl;

    } else {
        double dmid = (dmax + dmin) / 2;
        newmin = dmid - newdist / 2;
        newmax = dmid + newdist / 2;
    }

    double mmin, mmax;
    mmin = 0;
    mmax = double(sr) / 2;
    
    if (newmin < mmin) {
        newmax += (mmin - newmin);
        newmin = mmin;
    }
    if (newmax > mmax) {
        newmax = mmax;
    }
    
//    SVDEBUG << "SpectrogramLayer::setVerticalZoomStep: " << step << ": " << newmin << " -> " << newmax << " (range " << newdist << ")" << endl;

    setMinFrequency(int(lrint(newmin)));
    setMaxFrequency(int(lrint(newmax)));
}

RangeMapper *
SpectrogramLayer::getNewVerticalZoomRangeMapper() const
{
    auto model = ModelById::getAs<DenseTimeValueModel>(m_model);
    if (!model) return nullptr;
    return new SpectrogramRangeMapper(model->getSampleRate(), getFFTSize());
}

void
SpectrogramLayer::updateMeasureRectYCoords(LayerGeometryProvider *v, const MeasureRect &r) const
{
    int y0 = 0;
    if (r.startY > 0.0) y0 = int(getYForFrequency(v, r.startY));
    
    int y1 = y0;
    if (r.endY > 0.0) y1 = int(getYForFrequency(v, r.endY));

//    SVDEBUG << "SpectrogramLayer::updateMeasureRectYCoords: start " << r.startY << " -> " << y0 << ", end " << r.endY << " -> " << y1 << endl;

    r.pixrect = QRect(r.pixrect.x(), y0, r.pixrect.width(), y1 - y0);
}

void
SpectrogramLayer::setMeasureRectYCoord(LayerGeometryProvider *v, MeasureRect &r, bool start, int y) const
{
    if (start) {
        r.startY = getFrequencyForY(v, y);
        r.endY = r.startY;
    } else {
        r.endY = getFrequencyForY(v, y);
    }
//    SVDEBUG << "SpectrogramLayer::setMeasureRectYCoord: start " << r.startY << " <- " << y << ", end " << r.endY << " <- " << y << endl;

}

void
SpectrogramLayer::toXml(QTextStream &stream,
                        QString indent, QString extraAttributes) const
{
    QString s;
    
    s += QString("channel=\"%1\" "
                 "windowSize=\"%2\" "
                 "windowHopLevel=\"%3\" "
                 "oversampling=\"%4\" "
                 "gain=\"%5\" "
                 "threshold=\"%6\" ")
        .arg(m_channel)
        .arg(m_windowSize)
        .arg(m_windowHopLevel)
        .arg(m_oversampling)
        .arg(m_gain)
        .arg(m_threshold);

    s += QString("minFrequency=\"%1\" "
                 "maxFrequency=\"%2\" "
                 "colourScale=\"%3\" "
                 "colourRotation=\"%4\" "
                 "frequencyScale=\"%5\" "
                 "binDisplay=\"%6\" ")
        .arg(m_minFrequency)
        .arg(m_maxFrequency)
        .arg(convertFromColourScale(m_colourScale, m_colourScaleMultiple))
        .arg(m_colourRotation)
        .arg(int(m_binScale))
        .arg(int(m_binDisplay));

    // New-style colour map attribute, by string id rather than by
    // number

    s += QString("colourMap=\"%1\" ")
        .arg(ColourMapper::getColourMapId(m_colourMap));

    // Old-style colour map attribute

    s += QString("colourScheme=\"%1\" ")
        .arg(ColourMapper::getBackwardCompatibilityColourMap(m_colourMap));
    
    // New-style normalization attributes, allowing for more types of
    // normalization in future: write out the column normalization
    // type separately, and then whether we are normalizing visible
    // area as well afterwards
    
    s += QString("columnNormalization=\"%1\" ")
        .arg(m_normalization == ColumnNormalization::Max1 ? "peak" :
             m_normalization == ColumnNormalization::Hybrid ? "hybrid" : "none");

    // Old-style normalization attribute. We *don't* write out
    // normalizeHybrid here because the only release that would accept
    // it (Tony v1.0) has a totally different scale factor for
    // it. We'll just have to accept that session files from Tony
    // v2.0+ will look odd in Tony v1.0
    
    s += QString("normalizeColumns=\"%1\" ")
        .arg(m_normalization == ColumnNormalization::Max1 ? "true" : "false");

    // And this applies to both old- and new-style attributes
    
    s += QString("normalizeVisibleArea=\"%1\" ")
        .arg(m_normalizeVisibleArea ? "true" : "false");
    
    Layer::toXml(stream, indent, extraAttributes + " " + s);
}

void
SpectrogramLayer::setProperties(const QXmlAttributes &attributes)
{
    bool ok = false;

    int channel = attributes.value("channel").toInt(&ok);
    if (ok) setChannel(channel);

    int windowSize = attributes.value("windowSize").toUInt(&ok);
    if (ok) setWindowSize(windowSize);

    int windowHopLevel = attributes.value("windowHopLevel").toUInt(&ok);
    if (ok) setWindowHopLevel(windowHopLevel);
    else {
        int windowOverlap = attributes.value("windowOverlap").toUInt(&ok);
        // a percentage value
        if (ok) {
            if (windowOverlap == 0) setWindowHopLevel(0);
            else if (windowOverlap == 25) setWindowHopLevel(1);
            else if (windowOverlap == 50) setWindowHopLevel(2);
            else if (windowOverlap == 75) setWindowHopLevel(3);
            else if (windowOverlap == 90) setWindowHopLevel(4);
        }
    }

    int oversampling = attributes.value("oversampling").toUInt(&ok);
    if (ok) setOversampling(oversampling);

    float gain = attributes.value("gain").toFloat(&ok);
    if (ok) setGain(gain);

    float threshold = attributes.value("threshold").toFloat(&ok);
    if (ok) setThreshold(threshold);

    int minFrequency = attributes.value("minFrequency").toUInt(&ok);
    if (ok) {
        SVDEBUG << "SpectrogramLayer::setProperties: setting min freq to " << minFrequency << endl;
        setMinFrequency(minFrequency);
    }

    int maxFrequency = attributes.value("maxFrequency").toUInt(&ok);
    if (ok) {
        SVDEBUG << "SpectrogramLayer::setProperties: setting max freq to " << maxFrequency << endl;
        setMaxFrequency(maxFrequency);
    }

    auto colourScale = convertToColourScale
        (attributes.value("colourScale").toInt(&ok));
    if (ok) {
        setColourScale(colourScale.first);
        setColourScaleMultiple(colourScale.second);
    }

    QString colourMapId = attributes.value("colourMap");
    int colourMap = ColourMapper::getColourMapById(colourMapId);
    if (colourMap >= 0) {
        setColourMap(colourMap);
    } else {
        colourMap = attributes.value("colourScheme").toInt(&ok);
        if (ok && colourMap < ColourMapper::getColourMapCount()) {
            setColourMap(colourMap);
        }
    }

    int colourRotation = attributes.value("colourRotation").toInt(&ok);
    if (ok) setColourRotation(colourRotation);

    BinScale binScale = (BinScale)
        attributes.value("frequencyScale").toInt(&ok);
    if (ok) setBinScale(binScale);

    BinDisplay binDisplay = (BinDisplay)
        attributes.value("binDisplay").toInt(&ok);
    if (ok) setBinDisplay(binDisplay);

    bool haveNewStyleNormalization = false;
    
    QString columnNormalization = attributes.value("columnNormalization");

    if (columnNormalization != "") {

        haveNewStyleNormalization = true;

        if (columnNormalization == "peak") {
            setNormalization(ColumnNormalization::Max1);
        } else if (columnNormalization == "hybrid") {
            setNormalization(ColumnNormalization::Hybrid);
        } else if (columnNormalization == "none") {
            setNormalization(ColumnNormalization::None);
        } else {
            SVCERR << "NOTE: Unknown or unsupported columnNormalization attribute \""
                 << columnNormalization << "\"" << endl;
        }
    }

    if (!haveNewStyleNormalization) {

        bool normalizeColumns =
            (attributes.value("normalizeColumns").trimmed() == "true");
        if (normalizeColumns) {
            setNormalization(ColumnNormalization::Max1);
        }

        bool normalizeHybrid =
            (attributes.value("normalizeHybrid").trimmed() == "true");
        if (normalizeHybrid) {
            setNormalization(ColumnNormalization::Hybrid);
        }
    }

    bool normalizeVisibleArea =
        (attributes.value("normalizeVisibleArea").trimmed() == "true");
    setNormalizeVisibleArea(normalizeVisibleArea);

    if (!haveNewStyleNormalization && m_normalization == ColumnNormalization::Hybrid) {
        // Tony v1.0 is (and hopefully will remain!) the only released
        // SV-a-like to use old-style attributes when saving sessions
        // that ask for hybrid normalization. It saves them with the
        // wrong gain factor, so hack in a fix for that here -- this
        // gives us backward but not forward compatibility.
        setGain(m_gain / float(getFFTSize() / 2));
    }
}