diff options
Diffstat (limited to 'examples/multimediawidgets/player/histogramwidget.cpp')
| -rw-r--r-- | examples/multimediawidgets/player/histogramwidget.cpp | 182 |
1 files changed, 181 insertions, 1 deletions
diff --git a/examples/multimediawidgets/player/histogramwidget.cpp b/examples/multimediawidgets/player/histogramwidget.cpp index ff8d84e9b..71c243e23 100644 --- a/examples/multimediawidgets/player/histogramwidget.cpp +++ b/examples/multimediawidgets/player/histogramwidget.cpp @@ -40,6 +40,54 @@ #include "histogramwidget.h" #include <QPainter> +#include <QHBoxLayout> + +template <class T> +static QVector<qreal> getBufferLevels(const T *buffer, int frames, int channels); + +class QAudioLevel : public QWidget +{ + Q_OBJECT +public: + explicit QAudioLevel(QWidget *parent = 0); + + // Using [0; 1.0] range + void setLevel(qreal level); + +protected: + void paintEvent(QPaintEvent *event); + +private: + qreal m_level; +}; + +QAudioLevel::QAudioLevel(QWidget *parent) + : QWidget(parent) + , m_level(0.0) +{ + setMinimumHeight(15); + setMaximumHeight(50); +} + +void QAudioLevel::setLevel(qreal level) +{ + if (m_level != level) { + m_level = level; + update(); + } +} + +void QAudioLevel::paintEvent(QPaintEvent *event) +{ + Q_UNUSED(event); + + QPainter painter(this); + // draw level + qreal widthLevel = m_level * width(); + painter.fillRect(0, 0, widthLevel, height(), Qt::red); + // clear the rest of the control + painter.fillRect(widthLevel, 0, width(), height(), Qt::black); +} HistogramWidget::HistogramWidget(QWidget *parent) : QWidget(parent) @@ -50,6 +98,7 @@ HistogramWidget::HistogramWidget(QWidget *parent) qRegisterMetaType<QVector<qreal> >("QVector<qreal>"); connect(&m_processor, SIGNAL(histogramReady(QVector<qreal>)), SLOT(setHistogram(QVector<qreal>))); m_processorThread.start(QThread::LowestPriority); + setLayout(new QHBoxLayout); } HistogramWidget::~HistogramWidget() @@ -60,7 +109,7 @@ HistogramWidget::~HistogramWidget() void HistogramWidget::processFrame(QVideoFrame frame) { - if (m_isBusy) + if (m_isBusy && frame.isValid()) return; //drop frame m_isBusy = true; @@ -68,6 +117,132 @@ void HistogramWidget::processFrame(QVideoFrame frame) Qt::QueuedConnection, Q_ARG(QVideoFrame, frame), Q_ARG(int, m_levels)); } +// This function returns the maximum possible sample value for a given audio format +qreal getPeakValue(const QAudioFormat& format) +{ + // Note: Only the most common sample formats are supported + if (!format.isValid()) + return qreal(0); + + if (format.codec() != "audio/pcm") + return qreal(0); + + switch (format.sampleType()) { + case QAudioFormat::Unknown: + break; + case QAudioFormat::Float: + if (format.sampleSize() != 32) // other sample formats are not supported + return qreal(0); + return qreal(1.00003); + case QAudioFormat::SignedInt: + if (format.sampleSize() == 32) + return qreal(INT_MAX); + if (format.sampleSize() == 16) + return qreal(SHRT_MAX); + if (format.sampleSize() == 8) + return qreal(CHAR_MAX); + break; + case QAudioFormat::UnSignedInt: + if (format.sampleSize() == 32) + return qreal(UINT_MAX); + if (format.sampleSize() == 16) + return qreal(USHRT_MAX); + if (format.sampleSize() == 8) + return qreal(UCHAR_MAX); + break; + } + + return qreal(0); +} + +// returns the audio level for each channel +QVector<qreal> getBufferLevels(const QAudioBuffer& buffer) +{ + QVector<qreal> values; + + if (!buffer.isValid()) + return values; + + if (!buffer.format().isValid() || buffer.format().byteOrder() != QAudioFormat::LittleEndian) + return values; + + if (buffer.format().codec() != "audio/pcm") + return values; + + int channelCount = buffer.format().channelCount(); + values.fill(0, channelCount); + qreal peak_value = getPeakValue(buffer.format()); + if (qFuzzyCompare(peak_value, qreal(0))) + return values; + + switch (buffer.format().sampleType()) { + case QAudioFormat::Unknown: + case QAudioFormat::UnSignedInt: + if (buffer.format().sampleSize() == 32) + values = getBufferLevels(buffer.constData<quint32>(), buffer.frameCount(), channelCount); + if (buffer.format().sampleSize() == 16) + values = getBufferLevels(buffer.constData<quint16>(), buffer.frameCount(), channelCount); + if (buffer.format().sampleSize() == 8) + values = getBufferLevels(buffer.constData<quint8>(), buffer.frameCount(), channelCount); + for (int i = 0; i < values.size(); ++i) + values[i] = qAbs(values.at(i) - peak_value / 2) / (peak_value / 2); + break; + case QAudioFormat::Float: + if (buffer.format().sampleSize() == 32) { + values = getBufferLevels(buffer.constData<float>(), buffer.frameCount(), channelCount); + for (int i = 0; i < values.size(); ++i) + values[i] /= peak_value; + } + break; + case QAudioFormat::SignedInt: + if (buffer.format().sampleSize() == 32) + values = getBufferLevels(buffer.constData<qint32>(), buffer.frameCount(), channelCount); + if (buffer.format().sampleSize() == 16) + values = getBufferLevels(buffer.constData<qint16>(), buffer.frameCount(), channelCount); + if (buffer.format().sampleSize() == 8) + values = getBufferLevels(buffer.constData<qint8>(), buffer.frameCount(), channelCount); + for (int i = 0; i < values.size(); ++i) + values[i] /= peak_value; + break; + } + + return values; +} + +template <class T> +QVector<qreal> getBufferLevels(const T *buffer, int frames, int channels) +{ + QVector<qreal> max_values; + max_values.fill(0, channels); + + for (int i = 0; i < frames; ++i) { + for (int j = 0; j < channels; ++j) { + qreal value = qAbs(qreal(buffer[i * channels + j])); + if (value > max_values.at(j)) + max_values.replace(j, value); + } + } + + return max_values; +} + +void HistogramWidget::processBuffer(QAudioBuffer buffer) +{ + if (audioLevels.count() != buffer.format().channelCount()) { + qDeleteAll(audioLevels); + audioLevels.clear(); + for (int i = 0; i < buffer.format().channelCount(); ++i) { + QAudioLevel *level = new QAudioLevel(this); + audioLevels.append(level); + layout()->addWidget(level); + } + } + + QVector<qreal> levels = getBufferLevels(buffer); + for (int i = 0; i < levels.count(); ++i) + audioLevels.at(i)->setLevel(levels.at(i)); +} + void HistogramWidget::setHistogram(QVector<qreal> histogram) { m_isBusy = false; @@ -79,6 +254,9 @@ void HistogramWidget::paintEvent(QPaintEvent *event) { Q_UNUSED(event); + if (!audioLevels.isEmpty()) + return; + QPainter painter(this); if (m_histogram.isEmpty()) { @@ -152,3 +330,5 @@ void FrameProcessor::processFrame(QVideoFrame frame, int levels) emit histogramReady(histogram); } + +#include "histogramwidget.moc" |