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@1038: #include "base/BaseTypes.h"
Chris@317: #include "FileSource.h"
Chris@316: 
Chris@327: #include <vector>
Chris@632: #include <map>
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@1038:     sv_frame_t getFrameCount() const { return m_frameCount; }
Chris@929:     int getChannelCount() const { return m_channelCount; }
Chris@1040:     sv_samplerate_t getSampleRate() const { return m_sampleRate; }
Chris@660: 
Chris@1040:     virtual sv_samplerate_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@1010:     /**
Chris@1010:      * Return the local file path of the audio data. This is the
Chris@1010:      * location most likely to contain readable audio data: it may be
Chris@1010:      * in a different place or format from the originally specified
Chris@1010:      * location, for example if the file has been retrieved and
Chris@1010:      * decoded. In some cases there may be no local file path, and
Chris@1010:      * this will return "" if there is none.
Chris@1010:      */
Chris@1010:     virtual QString getLocalFilename() const { return ""; }
Chris@1010:     
Chris@632:     typedef std::map<QString, QString> TagMap;
Chris@632:     virtual TagMap getTags() const { return TagMap(); }
Chris@632: 
Chris@823:     /**
Chris@823:      * Return true if this file supports fast seek and random
Chris@823:      * access. Typically this will be true for uncompressed formats
Chris@823:      * and false for compressed ones.
Chris@823:      */
Chris@823:     virtual bool isQuicklySeekable() const = 0;
Chris@823: 
Chris@148:     /** 
Chris@327:      * Return interleaved samples for count frames from index start.
Chris@327:      * The resulting sample block will contain count *
Chris@989:      * getChannelCount() samples (or fewer if end of file is
Chris@989:      * reached). The caller does not need to allocate space and any
Chris@989:      * existing content in the SampleBlock will be erased.
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@1041:     virtual SampleBlock getInterleavedFrames(sv_frame_t start, sv_frame_t count) 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@1041:     virtual std::vector<SampleBlock> getDeInterleavedFrames(sv_frame_t start, sv_frame_t count) 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@1038:     sv_frame_t m_frameCount;
Chris@929:     int m_channelCount;
Chris@1040:     sv_samplerate_t m_sampleRate;
Chris@148: };
Chris@148: 
Chris@148: #endif