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  ** This file is part of the Qt Toolkit.
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  ** accordance with the commercial license agreement provided with the
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  #ifndef WAVEDECODER_H
  #define WAVEDECODER_H
  
  //
  //  W A R N I N G
  //  -------------
  //
  // This file is not part of the Qt API.  It exists for the convenience
  // of other Qt classes.  This header file may change from version to
  // version without notice, or even be removed.
  //
  // We mean it.
  //
  
  #include <QtCore/qiodevice.h>
  #include <qaudioformat.h>
  
  
  QT_BEGIN_NAMESPACE
  
  
  
  class QWaveDecoder : public QIODevice
  {
      Q_OBJECT
  
  public:
      explicit QWaveDecoder(QIODevice *source, QObject *parent = 0);
      ~QWaveDecoder();
  
      QAudioFormat audioFormat() const;
      int duration() const;
  
      qint64 size() const override;
      bool isSequential() const override;
      qint64 bytesAvailable() const override;
  
  Q_SIGNALS:
      void formatKnown();
      void parsingError();
  
  private Q_SLOTS:
      void handleData();
  
  private:
      qint64 readData(char *data, qint64 maxlen) override;
      qint64 writeData(const char *data, qint64 len) override;
  
      bool enoughDataAvailable();
      bool findChunk(const char *chunkId);
      void discardBytes(qint64 numBytes);
      void parsingFailed();
  
      enum State {
          InitialState,
          WaitingForFormatState,
          WaitingForDataState
      };
  
      struct chunk
      {
          char        id[4];
          quint32     size;
      };
      bool peekChunk(chunk* pChunk, bool handleEndianness = true);
  
      struct RIFFHeader
      {
          chunk       descriptor;
          char        type[4];
      };
      struct WAVEHeader
      {
          chunk       descriptor;
          quint16     audioFormat;
          quint16     numChannels;
          quint32     sampleRate;
          quint32     byteRate;
          quint16     blockAlign;
          quint16     bitsPerSample;
      };
  
      bool haveFormat;
      qint64 dataSize;
      QAudioFormat format;
      QIODevice *source;
      State state;
      quint32 junkToSkip;
      bool bigEndian;
  };
  
  QT_END_NAMESPACE
  
  #endif // WAVEDECODER_H
  