Duck status

src/models/multitrackmodel.cpp

@@ -48,6 +48,11 @@ static QByteArray trackAudioLevelPrefix(int mltTrackIndex)
     return QStringLiteral("meta.track.%1.audio_level.").arg(mltTrackIndex).toLatin1();
 }
 
+static QByteArray trackDuckLevelPrefix(int mltTrackIndex)
+{
+    return QStringLiteral("meta.track.%1.").arg(mltTrackIndex).toLatin1();
+}
+
 static double audioLevelDbFromFilter(Mlt::Filter *filter)
 {
     static const char *kAudioLevelLeft = "_audio_level.0";
@@ -744,7 +749,13 @@ void MultitrackModel::updateTrackAudioLevels(const SharedFrame &frame)
             = QStringLiteral("meta.track.%1.audio_level.1").arg(mltTrackIndex).toLatin1();
         const double left = frame.get_double(leftKey.constData());
         const double right = frame.get_double(rightKey.constData());
-        const double audioLevel = audioLevelDbFromLinear(left, right);
+        double audioLevel = audioLevelDbFromLinear(left, right);
+
+        // audiolevel measures before the mix transition applies ducking, so subtract it here.
+        const QByteArray duckKey = trackDuckLevelPrefix(mltTrackIndex) + "duck_level";
+        const double duckReduction = frame.get_double(duckKey.constData());
+        if (duckReduction > 0.0)
+            audioLevel = qMax(audioLevel - duckReduction, -100.0);
 
         setTrackAudioLevel(row, audioLevel);
     }
@@ -812,6 +823,10 @@ void MultitrackModel::syncTrackAudioLevelFilterPrefixes()
         std::unique_ptr<Mlt::Filter> levelFilter(
             ensureTrackAudioLevelFilter(track.data(), mltTrackIndex));
         Q_UNUSED(levelFilter)
+
+        QScopedPointer<Mlt::Transition> mix(getTransition("mix", mltTrackIndex));
+        if (mix && mix->is_valid())
+            mix->set("prefix", trackDuckLevelPrefix(mltTrackIndex).constData());
     }
 }
 

src/widgets/trackpropertieswidget.cpp

@@ -20,12 +20,14 @@
 
 #include "commands/timelinecommands.h"
 #include "mainwindow.h"
+#include "sharedframe.h"
 #include "shotcut_mlt_properties.h"
 #include "util.h"
 
 #include <Mlt.h>
+#include <QHideEvent>
 #include <QScopedPointer>
-#include <QTimer>
+#include <QShowEvent>
 
 static const char *BLEND_PROPERTY_CAIROBLEND = "1";
 static const char *BLEND_PROPERTY_QTBLEND = "compositing";
@@ -42,7 +44,7 @@ TrackPropertiesWidget::TrackPropertiesWidget(Mlt::Producer &track,
     : QWidget(parent)
     , ui(new Ui::TrackPropertiesWidget)
     , m_track(track)
-    , m_duckStatusTimer(new QTimer(this))
+    , m_trackIndex(-1)
 {
     ui->setupUi(this);
     Util::setColorsToHighlight(ui->nameLabel);
@@ -63,15 +65,6 @@ TrackPropertiesWidget::TrackPropertiesWidget(Mlt::Producer &track,
         }
     }
 
-    m_duckStatusTimer->setInterval(100);
-    if (showDucking) {
-        connect(m_duckStatusTimer,
-                &QTimer::timeout,
-                this,
-                &TrackPropertiesWidget::refreshDuckStatus);
-        m_duckStatusTimer->start();
-    }
-
     if (showBlend) {
         QScopedPointer<Mlt::Transition> transition(getTransition("qtblend"));
         if (!transition)
@@ -165,7 +158,6 @@ TrackPropertiesWidget::TrackPropertiesWidget(Mlt::Producer &track,
 
 TrackPropertiesWidget::~TrackPropertiesWidget()
 {
-    m_duckStatusTimer->stop();
     delete ui;
 }
 
@@ -192,6 +184,36 @@ void TrackPropertiesWidget::updateDuckStatus(double value)
     ui->duckStatusValueLabel->setFormat(QString::number(clamped, 'f', 1) + tr(" dB"));
 }
 
+void TrackPropertiesWidget::showEvent(QShowEvent *event)
+{
+    QWidget::showEvent(event);
+    if (!ui->duckingHeadingLabel->isVisible())
+        return;
+    connect(MLT.videoWidget(),
+            SIGNAL(frameDisplayed(const SharedFrame &)),
+            this,
+            SLOT(onShowFrame(const SharedFrame &)));
+}
+
+void TrackPropertiesWidget::hideEvent(QHideEvent *event)
+{
+    QWidget::hideEvent(event);
+    if (!ui->duckingHeadingLabel->isVisible())
+        return;
+    disconnect(MLT.videoWidget(),
+               SIGNAL(frameDisplayed(const SharedFrame &)),
+               this,
+               SLOT(onShowFrame(const SharedFrame &)));
+}
+
+void TrackPropertiesWidget::onShowFrame(const SharedFrame &frame)
+{
+    if (m_trackIndex < 0 || !frame.is_valid())
+        return;
+    const QByteArray key = QStringLiteral("meta.track.%1.duck_level").arg(m_trackIndex).toLatin1();
+    updateDuckStatus(frame.get_double(key.constData()));
+}
+
 Mlt::Transition *TrackPropertiesWidget::getTransition(const QString &name)
 {
     // track.consumer() is the multitrack
@@ -206,6 +228,7 @@ Mlt::Transition *TrackPropertiesWidget::getTransition(const QString &name)
             if (producer->get_producer() == m_track.get_producer())
                 break;
         }
+        m_trackIndex = trackIndex;
 
         // Iterate the consumers until found transition by mlt_service and track_b index.
         while (service && service->is_valid() && mlt_service_tractor_type != service->type()) {
@@ -344,11 +367,3 @@ void TrackPropertiesWidget::onDuckFadeOutChanged(double value)
     ui->duckFadeOutSpinBox->setValue(value);
     ui->duckFadeOutSpinBox->blockSignals(false);
 }
-
-void TrackPropertiesWidget::refreshDuckStatus()
-{
-    QScopedPointer<Mlt::Transition> transition(getTransition("mix"));
-    if (transition && transition->is_valid()) {
-        updateDuckStatus(transition->get_double(MIX_PROPERTY_DUCK_LEVEL));
-    }
-}

src/widgets/trackpropertieswidget.h

@@ -22,14 +22,15 @@
 #include <MltProducer.h>
 #include <QWidget>
 
-class QTimer;
-
 namespace Ui {
 class TrackPropertiesWidget;
 }
 namespace Mlt {
 class Transition;
 }
+class SharedFrame;
+class QShowEvent;
+class QHideEvent;
 
 class TrackPropertiesWidget : public QWidget
 {
@@ -53,7 +54,11 @@ private slots:
     void onDuckAttenuationChanged(double value);
     void onDuckFadeInChanged(double value);
     void onDuckFadeOutChanged(double value);
-    void refreshDuckStatus();
+    void onShowFrame(const SharedFrame &frame);
+
+protected:
+    void showEvent(QShowEvent *event) override;
+    void hideEvent(QHideEvent *event) override;
 
 private:
     Mlt::Transition *getTransition(const QString &name);
@@ -62,7 +67,7 @@ private slots:
 
     Ui::TrackPropertiesWidget *ui;
     Mlt::Producer m_track;
-    QTimer *m_duckStatusTimer;
+    int m_trackIndex;
 };
 
 #endif // TRACKPROPERTIESWIDGET_H