WAVAudioFileSource.hh

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// "liveMedia"
// Copyright (c) 1996-2021 Live Networks, Inc.  All rights reserved.
// A WAV audio file source
// NOTE: Samples are returned in little-endian order (the same order in which
// they were stored in the file).
// C++ header
 
#ifndef _WAV_AUDIO_FILE_SOURCE_HH
#define _WAV_AUDIO_FILE_SOURCE_HH
 
#ifndef _AUDIO_INPUT_DEVICE_HH
#include "AudioInputDevice.hh"
#endif
 
typedef enum {
  WA_PCM = 0x01,
  WA_PCMA = 0x06,
  WA_PCMU = 0x07,
  WA_IMA_ADPCM = 0x11,
  WA_UNKNOWN
} WAV_AUDIO_FORMAT;
 
 
class WAVAudioFileSource: public AudioInputDevice {
public:
 
  static WAVAudioFileSource* createNew(UsageEnvironment& env,
                                        char const* fileName);
 
  unsigned numPCMBytes() const;
  void setScaleFactor(int scale);
  void seekToPCMByte(unsigned byteNumber);
  void limitNumBytesToStream(unsigned numBytesToStream);
      // if "numBytesToStream" is >0, then we limit the stream to that number of bytes, before treating it as EOF
 
  unsigned char getAudioFormat();
 
protected:
  WAVAudioFileSource(UsageEnvironment& env, FILE* fid);
        // called only by createNew()
 
  virtual ~WAVAudioFileSource();
 
  static void fileReadableHandler(WAVAudioFileSource* source, int mask);
  void doReadFromFile();
 
private:
  // redefined virtual functions:
  virtual void doGetNextFrame();
  virtual void doStopGettingFrames();
  virtual Boolean setInputPort(int portIndex);
  virtual double getAverageLevel() const;
 
protected:
  unsigned fPreferredFrameSize;
 
private:
  FILE* fFid;
  double fPlayTimePerSample; // useconds
  Boolean fFidIsSeekable;
  unsigned fLastPlayTime; // useconds
  Boolean fHaveStartedReading;
  unsigned fWAVHeaderSize;
  unsigned fFileSize;
  int fScaleFactor;
  Boolean fLimitNumBytesToStream;
  unsigned fNumBytesToStream; // used iff "fLimitNumBytesToStream" is True
  unsigned char fAudioFormat;
};
 
#endif