mpd/src/ReplayGainInfo.cxx

43 lines
1.2 KiB
C++

/*
* Copyright 2003-2021 The Music Player Daemon Project
* http://www.musicpd.org
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "ReplayGainInfo.hxx"
#include "ReplayGainConfig.hxx"
#include <cmath>
float
ReplayGainTuple::CalculateScale(const ReplayGainConfig &config) const noexcept
{
float scale;
if (IsDefined()) {
scale = std::pow(10.0f, gain / 20.0f);
scale *= config.preamp;
if (scale > 15.0f)
scale = 15.0f;
if (config.limit && scale * peak > 1.0f)
scale = 1.0f / peak;
} else
scale = config.missing_preamp;
return scale;
}