view data/fileio/WavFileReader.h @ 1196:c7b9c902642f spectrogram-minor-refactor

Fix threshold in spectrogram -- it wasn't working in the last release.
There is a new protocol for this. Formerly the threshold parameter had a
range from -50dB to 0 with the default at -50, and -50 treated internally
as "no threshold". However, there was a hardcoded, hidden internal threshold
for spectrogram colour mapping at -80dB with anything below this being rounded
to zero. Now the threshold parameter has range -81 to -1 with the default
at -80, -81 is treated internally as "no threshold", and there is no hidden
internal threshold. So the default behaviour is the same as before, an
effective -80dB threshold, but it is now possible to change this in both
directions. Sessions reloaded from prior versions may look slightly different
because, if the session says there should be no threshold, there will now
actually be no threshold instead of having the hidden internal one.

Still need to do something in the UI to make it apparent that the -81dB
setting removes the threshold entirely. This is at least no worse than the
previous, also obscured, magic -50dB setting.

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Sonic Visualiser
    An audio file viewer and annotation editor.
    Centre for Digital Music, Queen Mary, University of London.
    This file copyright 2006 Chris Cannam.
    
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
    published by the Free Software Foundation; either version 2 of the
    License, or (at your option) any later version.  See the file
    COPYING included with this distribution for more information.
*/

#ifndef _WAV_FILE_READER_H_
#define _WAV_FILE_READER_H_

#include "AudioFileReader.h"

#include <sndfile.h>
#include <QMutex>

#include <set>

/**
 * Reader for audio files using libsndfile.
 *
 * This is typically intended for seekable file types that can be read
 * directly (e.g. WAV, AIFF etc).
 *
 * Compressed files supported by libsndfile (e.g. Ogg, FLAC) should
 * normally be read using DecodingWavFileReader instead (which decodes
 * to an intermediate cached file).
 */
class WavFileReader : public AudioFileReader
{
public:
    WavFileReader(FileSource source, bool fileUpdating = false);
    virtual ~WavFileReader();

    virtual QString getLocation() const { return m_source.getLocation(); }
    virtual QString getError() const { return m_error; }

    virtual QString getLocalFilename() const { return m_path; }
    
    virtual bool isQuicklySeekable() const { return m_seekable; }
    
    /** 
     * Must be safe to call from multiple threads with different
     * arguments on the same object at the same time.
     */
    virtual std::vector<float> getInterleavedFrames(sv_frame_t start, sv_frame_t count) const;
    
    static void getSupportedExtensions(std::set<QString> &extensions);
    static bool supportsExtension(QString ext);
    static bool supportsContentType(QString type);
    static bool supports(FileSource &source);

    virtual int getDecodeCompletion() const { return 100; }

    bool isUpdating() const { return m_updating; }

    void updateFrameCount();
    void updateDone();

protected:
    SF_INFO m_fileInfo;
    SNDFILE *m_file;

    FileSource m_source;
    QString m_path;
    QString m_error;

    bool m_seekable;

    mutable QMutex m_mutex;
    mutable std::vector<float> m_buffer;
    mutable sv_frame_t m_lastStart;
    mutable sv_frame_t m_lastCount;

    bool m_updating;
};

#endif