audiostream.cpp

#include "audiostream.h"
#include <QDebug>
#include <QAudioDeviceInfo>
#include <QtCore/qendian.h>


AudioStream::AudioStream(QObject *parent)
    : QIODevice(parent)
    , m_format()
    , m_audioInput()
    , m_maxAmplitude(0)
    , m_level(0.0)
    , m_client()
    , hasClientSocket(false)
{
//    m_client->open(QIODevice::WriteOnly | QIODevice::Truncate | QIODevice::Unbuffered);
    m_format.setFrequency(8000);
    m_format.setChannels(1);
    m_format.setSampleSize(16);
    m_format.setSampleType(QAudioFormat::SignedInt);
    m_format.setByteOrder(QAudioFormat::LittleEndian);
    m_format.setCodec("audio/pcm");

    QAudioDeviceInfo info(QAudioDeviceInfo::defaultInputDevice());
    if (!info.isFormatSupported(m_format)) {
        qWarning() << "Default format not supported - trying to use nearest";
        m_format = info.nearestFormat(m_format);
    }

    switch (m_format.sampleSize()) {
    case 8:
        switch (m_format.sampleType()) {
        case QAudioFormat::UnSignedInt:
            m_maxAmplitude = 255;
            break;
        case QAudioFormat::SignedInt:
            m_maxAmplitude = 127;
            break;
        default:
            break;
        }
        break;
    case 16:
        switch (m_format.sampleType()) {
        case QAudioFormat::UnSignedInt:
            m_maxAmplitude = 65535;
            break;
        case QAudioFormat::SignedInt:
            m_maxAmplitude = 32767;
            break;
        default:
            break;
        }
        break;
    default:
        break;
    }

    m_audioInput = new QAudioInput(QAudioDeviceInfo::defaultInputDevice(), m_format, this);
}

void AudioStream::start()
{
    open(QIODevice::WriteOnly | QIODevice::Truncate | QIODevice::Unbuffered);
    m_audioInput->start(this);
}

void AudioStream::stop()
{
    m_audioInput->stop();
    close();
}

qint64 AudioStream::writeData(const char *data, qint64 len)
{
    if (m_maxAmplitude) {
        Q_ASSERT(m_format.sampleSize() % 8 == 0);
        const int channelBytes = m_format.sampleSize() / 8;
        const int sampleBytes = m_format.channels() * channelBytes;
        Q_ASSERT(len % sampleBytes == 0);
        const int numSamples = len / sampleBytes;

        quint16 maxValue = 0;
        const unsigned char *ptr = reinterpret_cast<const unsigned char *>(data);

        for (int i = 0; i < numSamples; ++i) {
            for(int j = 0; j < m_format.channels(); ++j) {
                quint16 value = 0;

                if (m_format.sampleSize() == 8 && m_format.sampleType() == QAudioFormat::UnSignedInt) {
                    value = *reinterpret_cast<const quint8*>(ptr);
                } else if (m_format.sampleSize() == 8 && m_format.sampleType() == QAudioFormat::SignedInt) {
                    value = qAbs(*reinterpret_cast<const qint8*>(ptr));
                } else if (m_format.sampleSize() == 16 && m_format.sampleType() == QAudioFormat::UnSignedInt) {
                    if (m_format.byteOrder() == QAudioFormat::LittleEndian)
                        value = qFromLittleEndian<quint16>(ptr);
                    else
                        value = qFromBigEndian<quint16>(ptr);
                } else if (m_format.sampleSize() == 16 && m_format.sampleType() == QAudioFormat::SignedInt) {
                    if (m_format.byteOrder() == QAudioFormat::LittleEndian)
                        value = qAbs(qFromLittleEndian<qint16>(ptr));
                    else
                        value = qAbs(qFromBigEndian<qint16>(ptr));
                }

                maxValue = qMax(value, maxValue);
                ptr += channelBytes;
            }
        }

        maxValue = qMin(maxValue, m_maxAmplitude);
        m_level = qreal(maxValue) / m_maxAmplitude;
    }



    emit updateLevel(m_level);

    if(hasClientSocket)
    {
        return m_client->write(data, len);
    }

    return len;
}

// Why do i need to do this?
qint64 AudioStream::readData(char *data, qint64 maxlen)
{
    Q_UNUSED(data)
    Q_UNUSED(maxlen)

    return 0;
}


void AudioStream::slotClientSocket(QIODevice *client)
{
    m_client = client;
    hasClientSocket = true;
}