qtmultimedia/src/plugins/audiocapture/audiocapturesession.h

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#ifndef AUDIOCAPTURESESSION_H
#define AUDIOCAPTURESESSION_H

#include <QFile>
#include <QUrl>
#include <QDir>
#include <QMutex>

#include "audioencodercontrol.h"
#include "audioinputselector.h"
#include "audiomediarecordercontrol.h"

#include <qaudioformat.h>
#include <qaudioinput.h>
#include <qaudiodeviceinfo.h>

QT_BEGIN_NAMESPACE

class AudioCaptureProbeControl;

class FileProbeProxy: public QFile {
public:
    void startProbes(const QAudioFormat& format);
    void stopProbes();
    void addProbe(AudioCaptureProbeControl *probe);
    void removeProbe(AudioCaptureProbeControl *probe);

protected:
    virtual qint64 writeData(const char *data, qint64 len);

private:
    QAudioFormat m_format;
    QList<AudioCaptureProbeControl*> m_probes;
    QMutex m_probeMutex;
};


class AudioCaptureSession : public QObject
{
    Q_OBJECT

public:
    AudioCaptureSession(QObject *parent = 0);
    ~AudioCaptureSession();

    QAudioFormat format() const;
    void setFormat(const QAudioFormat &format);

    QString containerFormat() const;
    void setContainerFormat(const QString &formatMimeType);

    QUrl outputLocation() const;
    bool setOutputLocation(const QUrl& location);

    qint64 position() const;

    void setState(QMediaRecorder::State state);
    QMediaRecorder::State state() const;
    QMediaRecorder::Status status() const;

    void addProbe(AudioCaptureProbeControl *probe);
    void removeProbe(AudioCaptureProbeControl *probe);

    void setCaptureDevice(const QString &deviceName);

signals:
    void stateChanged(QMediaRecorder::State state);
    void statusChanged(QMediaRecorder::Status status);
    void positionChanged(qint64 position);
    void actualLocationChanged(const QUrl &location);
    void error(int error, const QString &errorString);

private slots:
    void audioInputStateChanged(QAudio::State state);
    void notify();

private:
    void record();
    void pause();
    void stop();

    void setStatus(QMediaRecorder::Status status);

    QDir defaultDir() const;
    QString generateFileName(const QString &requestedName,
                             const QString &extension) const;
    QString generateFileName(const QDir &dir, const QString &extension) const;

    FileProbeProxy file;
    QString m_captureDevice;
    QUrl m_requestedOutputLocation;
    QUrl m_actualOutputLocation;
    QMediaRecorder::State m_state;
    QMediaRecorder::Status m_status;
    QAudioInput *m_audioInput;
    QAudioDeviceInfo m_deviceInfo;
    QAudioFormat m_format;
    bool m_wavFile;

    // WAV header stuff

    struct chunk
    {
        char        id[4];
        quint32     size;
    };

    struct RIFFHeader
    {
        chunk       descriptor;
        char        type[4];
    };

    struct WAVEHeader
    {
        chunk       descriptor;
        quint16     audioFormat;        // PCM = 1
        quint16     numChannels;
        quint32     sampleRate;
        quint32     byteRate;
        quint16     blockAlign;
        quint16     bitsPerSample;
    };

    struct DATAHeader
    {
        chunk       descriptor;
//        quint8      data[];
    };

    struct CombinedHeader
    {
        RIFFHeader  riff;
        WAVEHeader  wave;
        DATAHeader  data;
    };

    CombinedHeader      header;
};

QT_END_NAMESPACE

#endif