Chris@148: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
Chris@148: 
Chris@148: /*
Chris@148:     Sonic Visualiser
Chris@148:     An audio file viewer and annotation editor.
Chris@148:     Centre for Digital Music, Queen Mary, University of London.
Chris@148:     This file copyright 2006 Chris Cannam.
Chris@148:     
Chris@148:     This program is free software; you can redistribute it and/or
Chris@148:     modify it under the terms of the GNU General Public License as
Chris@148:     published by the Free Software Foundation; either version 2 of the
Chris@148:     License, or (at your option) any later version.  See the file
Chris@148:     COPYING included with this distribution for more information.
Chris@148: */
Chris@148: 
Chris@148: #ifndef _AUDIO_FILE_READER_H_
Chris@148: #define _AUDIO_FILE_READER_H_
Chris@148: 
Chris@290: #include <QString>
Chris@148: 
Chris@317: #include "FileSource.h"
Chris@316: 
Chris@327: #include <vector>
Chris@327: 
Chris@327: typedef std::vector<float> SampleBlock;
Chris@327: 
Chris@175: class AudioFileReader : public QObject
Chris@148: {
Chris@175:     Q_OBJECT
Chris@175: 
Chris@148: public:
Chris@148:     virtual ~AudioFileReader() { }
Chris@148: 
Chris@148:     bool isOK() const { return (m_channelCount > 0); }
Chris@148: 
Chris@290:     virtual QString getError() const { return ""; }
Chris@148: 
Chris@148:     size_t getFrameCount() const { return m_frameCount; }
Chris@148:     size_t getChannelCount() const { return m_channelCount; }
Chris@148:     size_t getSampleRate() const { return m_sampleRate; }
Chris@297:     size_t getNativeRate() const { return m_sampleRate; } // if resampled
Chris@345: 
Chris@345:     /**
Chris@345:      * Return the location of the audio data in the reader (as passed
Chris@345:      * in to the FileSource constructor, for example).
Chris@345:      */
Chris@345:     virtual QString getLocation() const { return ""; }
Chris@148:     
Chris@271:     /**
Chris@271:      * Return the title of the work in the audio file, if known.  This
Chris@271:      * may be implemented by subclasses that support file tagging.
Chris@271:      * This is not the same thing as the file name.
Chris@271:      */
Chris@290:     virtual QString getTitle() const { return ""; }
Chris@271: 
Chris@333:     /**
Chris@333:      * Return the "maker" of the work in the audio file, if known.
Chris@333:      * This could represent almost anything (band, composer,
Chris@333:      * conductor, artist etc).
Chris@333:      */
Chris@333:     virtual QString getMaker() const { return ""; }
Chris@333: 
Chris@148:     /** 
Chris@327:      * Return interleaved samples for count frames from index start.
Chris@327:      * The resulting sample block will contain count *
Chris@327:      * getChannelCount() samples (or fewer if end of file is reached).
Chris@327:      *
Chris@148:      * The subclass implementations of this function must be
Chris@148:      * thread-safe -- that is, safe to call from multiple threads with
Chris@148:      * different arguments on the same object at the same time.
Chris@148:      */
Chris@148:     virtual void getInterleavedFrames(size_t start, size_t count,
Chris@148: 				      SampleBlock &frames) const = 0;
Chris@175: 
Chris@327:     /**
Chris@327:      * Return de-interleaved samples for count frames from index
Chris@327:      * start.  Implemented in this class (it calls
Chris@327:      * getInterleavedFrames and de-interleaves).  The resulting vector
Chris@327:      * will contain getChannelCount() sample blocks of count samples
Chris@327:      * each (or fewer if end of file is reached).
Chris@327:      */
Chris@327:     virtual void getDeInterleavedFrames(size_t start, size_t count,
Chris@327:                                         std::vector<SampleBlock> &frames) const;
Chris@327: 
Chris@265:     // only subclasses that do not know exactly how long the audio
Chris@265:     // file is until it's been completely decoded should implement this
Chris@265:     virtual int getDecodeCompletion() const { return 100; } // %
Chris@265: 
Chris@176:     virtual bool isUpdating() const { return false; }
Chris@176: 
Chris@175: signals:
Chris@175:     void frameCountChanged();
Chris@148:     
Chris@148: protected:
Chris@148:     size_t m_frameCount;
Chris@148:     size_t m_channelCount;
Chris@148:     size_t m_sampleRate;
Chris@148: };
Chris@148: 
Chris@148: #endif