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/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* 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.
*
*/
// Based on eos' (I)RDFT code which is in turn
// Based upon the (I)RDFT code in FFmpeg
// Copyright (c) 2009 Alex Converse <alex dot converse at gmail dot com>
#ifndef COMMON_RDFT_H
#define COMMON_RDFT_H
#include "common/scummsys.h"
#include "common/math.h"
#include "common/fft.h"
namespace Common {
class SineTable;
class CosineTable;
/**
* (Inverse) Real Discrete Fourier Transform.
*
* Used in engines:
* - scumm
*/
class RDFT {
public:
enum TransformType {
DFT_R2C,
IDFT_C2R,
IDFT_R2C,
DFT_C2R
};
RDFT(int bits, TransformType trans);
~RDFT();
void calc(float *data);
private:
int _bits;
int _inverse;
int _signConvention;
SineTable *_sin;
CosineTable *_cos;
const float *_tSin;
const float *_tCos;
FFT *_fft;
};
} // End of namespace Common
#endif // COMMON_RDFT_H
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