1 files changed, 8 insertions, 8 deletions
diff --git a/examples/multimediawidgets/player/histogramwidget.h b/examples/multimediawidgets/player/histogramwidget.h
index a130477f8..a5c697dfb 100644
--- a/examples/multimediawidgets/player/histogramwidget.h
+++ b/examples/multimediawidgets/player/histogramwidget.h
@@ -66,7 +66,7 @@ public slots:
     void processFrame(QVideoFrame frame, int levels);
 
 signals:
-    void histogramReady(QVector<qreal> histogram);
+    void histogramReady(const QVector<qreal> &histogram);
 };
 
 class HistogramWidget : public QWidget
@@ -74,25 +74,25 @@ class HistogramWidget : public QWidget
     Q_OBJECT
 
 public:
-    explicit HistogramWidget(QWidget *parent = 0);
+    explicit HistogramWidget(QWidget *parent = nullptr);
     ~HistogramWidget();
     void setLevels(int levels) { m_levels = levels; }
 
 public slots:
-    void processFrame(QVideoFrame frame);
-    void processBuffer(QAudioBuffer buffer);
-    void setHistogram(QVector<qreal> histogram);
+    void processFrame(const QVideoFrame &frame);
+    void processBuffer(const QAudioBuffer &buffer);
+    void setHistogram(const QVector<qreal> &histogram);
 
 protected:
     void paintEvent(QPaintEvent *event) override;
 
 private:
     QVector<qreal> m_histogram;
-    int m_levels;
+    int m_levels = 128;
     FrameProcessor m_processor;
     QThread m_processorThread;
-    bool m_isBusy;
-    QVector<QAudioLevel *> audioLevels;
+    bool m_isBusy = false;
+    QVector<QAudioLevel *> m_audioLevels;
 };
 
 #endif // HISTOGRAMWIDGET_H