Gnash  0.8.10
SoundUtils.h
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00001 // SoundUtils.h     Utilities for handling sound data.
00002 // 
00003 //   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
00004 //   Free Software Foundation, Inc
00005 // 
00006 // This program is free software; you can redistribute it and/or modify
00007 // it under the terms of the GNU General Public License as published by
00008 // the Free Software Foundation; either version 3 of the License, or
00009 // (at your option) any later version.
00010 // 
00011 // This program is distributed in the hope that it will be useful,
00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014 // GNU General Public License for more details.
00015 // 
00016 // You should have received a copy of the GNU General Public License
00017 // along with this program; if not, write to the Free Software
00018 // Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
00019 
00020 #ifndef GNASH_SOUND_UTILS_H
00021 #define GNASH_SOUND_UTILS_H
00022 
00023 #include <algorithm>
00024 #include <boost/bind.hpp>
00025 #include <boost/cstdint.hpp>
00026 
00027 #include "SoundInfo.h"
00028 
00029 namespace gnash {
00030 namespace sound {
00031 
00033 //
00037 template<typename T>
00038 inline void
00039 adjustVolume(T* start, T* end, float volume)
00040 {
00041     std::transform(start, end, start,
00042             boost::bind(std::multiplies<float>(), volume, _1));
00043 }
00044 
00046 //
00054 inline size_t
00055 swfToOutSamples(const media::SoundInfo& sinfo, size_t swfSamples,
00056         const size_t outRate = 44100)
00057 {
00058     // NOTE: this was tested with inputs:
00059     //     - isStereo?0 is16bit()?1 sampleRate?11025
00060     //     - isStereo?0 is16bit()?1 sampleRate?22050
00061     //     - isStereo?1 is16bit()?1 sampleRate?22050
00062     //     - isStereo?0 is16bit()?1 sampleRate?44100
00063     //     - isStereo?1 is16bit()?1 sampleRate?44100
00064     //
00065     // TODO: test with other sample sizes !
00066     return swfSamples * (outRate / sinfo.getSampleRate());
00067 }
00068 
00069 } // namespace sound
00070 } // namespace gnash
00071 
00072 #endif