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/* -*- 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 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 AUDIO_FILE_SIZE_ESTIMATOR_H
#define AUDIO_FILE_SIZE_ESTIMATOR_H
#include "base/BaseTypes.h"
#include "data/fileio/FileSource.h"
namespace sv {
/**
* Estimate the number of samples in an audio file. For many
* compressed files this returns only a very approximate estimate,
* based on a rough estimate of compression ratio. Initially we're
* only aiming for a conservative estimate for purposes like "will
* this file fit in memory?" (and if unsure, say no).
*/
class AudioFileSizeEstimator
{
public:
/**
* Return an estimate of the number of samples (across all
* channels) in the given audio file, once it has been decoded and
* (if applicable) resampled to the given rate.
*
* This function is intended to be reasonably fast -- it may open
* the file, but it should not do any decoding. (However, if the
* file source is remote, it will probably be downloaded in its
* entirety before anything can be estimated.)
*
* The returned value is an estimate, and is deliberately usually
* on the high side. If the estimator has no idea at all, this
* will return 0.
*/
static sv_frame_t estimate(FileSource source,
sv_samplerate_t targetRate = 0);
};
} // end namespace sv
#endif
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