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52 lines
1.5 KiB
C
52 lines
1.5 KiB
C
/*
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* (I)RDFT transforms
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* Copyright (c) 2009 Alex Converse <alex dot converse at gmail dot com>
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*
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* This file is part of FFmpeg.
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*
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* FFmpeg is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with FFmpeg; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#if !defined(AVCODEC_RDFT_H) && (!defined(FFT_FLOAT) || FFT_FLOAT)
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#define AVCODEC_RDFT_H
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#include "config.h"
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#include "fft.h"
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struct RDFTContext {
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int nbits;
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int inverse;
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int sign_convention;
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/* pre/post rotation tables */
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const FFTSample *tcos;
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const FFTSample *tsin;
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int negative_sin;
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FFTContext fft;
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void (*rdft_calc)(struct RDFTContext *s, FFTSample *z);
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};
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/**
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* Set up a real FFT.
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* @param nbits log2 of the length of the input array
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* @param trans the type of transform
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*/
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int ff_rdft_init(RDFTContext *s, int nbits, enum RDFTransformType trans);
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void ff_rdft_end(RDFTContext *s);
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void ff_rdft_init_arm(RDFTContext *s);
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#endif /* AVCODEC_RDFT_H */
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