AFV initial commit

src/blackcore/afv/audio/output.cpp

@@ -0,0 +1,92 @@
+#include "output.h"
+
+#include <QDebug>
+#include <cmath>
+
+AudioOutputBuffer::AudioOutputBuffer(ISampleProvider *sampleProvider, QObject *parent) :
+    QIODevice(parent),
+    m_sampleProvider(sampleProvider)
+{ }
+
+qint64 AudioOutputBuffer::readData(char *data, qint64 maxlen)
+{
+    int sampleBytes = m_outputFormat.sampleSize() / 8;
+    int channelCount = m_outputFormat.channelCount();
+    int count = maxlen / ( sampleBytes * channelCount);
+    QVector<qint16> buffer;
+    m_sampleProvider->readSamples(buffer, count);
+
+    for (const qint16 sample : buffer)
+    {
+        qint16 sampleInput = sample;
+        sampleInput = qAbs(sampleInput);
+        if (sampleInput > m_maxSampleOutput)
+            m_maxSampleOutput = sampleInput;
+    }
+
+    m_sampleCount += buffer.size();
+    if (m_sampleCount >= c_sampleCountPerEvent)
+    {
+        OutputVolumeStreamArgs outputVolumeStreamArgs;
+        qint16 maxInt = std::numeric_limits<qint16>::max();
+        outputVolumeStreamArgs.PeakRaw = m_maxSampleOutput / maxInt;
+        outputVolumeStreamArgs.PeakDB = (float)(20 * std::log10(outputVolumeStreamArgs.PeakRaw));
+        float db = qBound(minDb, outputVolumeStreamArgs.PeakDB, maxDb);
+        float ratio = (db - minDb) / (maxDb - minDb);
+        if (ratio < 0.30)
+            ratio = 0;
+        if (ratio > 1.0)
+            ratio = 1;
+        outputVolumeStreamArgs.PeakVU = ratio;
+        emit outputVolumeStream(outputVolumeStreamArgs);
+        m_sampleCount = 0;
+        m_maxSampleOutput = 0;
+    }
+
+    memcpy(data, buffer.constData(), maxlen);
+    return maxlen;
+}
+
+qint64 AudioOutputBuffer::writeData(const char *data, qint64 len)
+{
+    Q_UNUSED(data);
+    Q_UNUSED(len);
+    return -1;
+}
+
+Output::Output(QObject *parent) : QObject(parent)
+{ }
+
+void Output::start(const QAudioDeviceInfo &device, ISampleProvider *sampleProvider)
+{
+    m_audioOutputBuffer = new AudioOutputBuffer(sampleProvider, this);
+    connect(m_audioOutputBuffer, &AudioOutputBuffer::outputVolumeStream, this, &Output::outputVolumeStream);
+
+    QAudioFormat outputFormat;
+    outputFormat.setSampleRate(48000);
+    outputFormat.setChannelCount(1);
+    outputFormat.setSampleSize(16);
+    outputFormat.setSampleType(QAudioFormat::SignedInt);
+    outputFormat.setByteOrder(QAudioFormat::LittleEndian);
+    outputFormat.setCodec("audio/pcm");
+
+    if (!device.isFormatSupported(outputFormat))
+    {
+        qWarning() << "Default format not supported - trying to use nearest";
+        outputFormat = device.nearestFormat(outputFormat);
+    }
+
+    m_audioOutputCom1.reset(new QAudioOutput(device, outputFormat));
+    // m_audioOutput->setBufferSize(bufferSize);
+    m_audioOutputBuffer->open(QIODevice::ReadWrite | QIODevice::Unbuffered);
+    m_audioOutputBuffer->setAudioFormat(outputFormat);
+    m_audioOutputCom1->start(m_audioOutputBuffer);
+
+    m_started = true;
+}
+
+void Output::stop()
+{
+    if (!m_started) { return; }
+    m_started = false;
+}