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/*
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 * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
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 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
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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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#ifndef AVCODEC_FFT_H
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#define AVCODEC_FFT_H
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#include <stdint.h>
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#include "config.h"
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#include "libavutil/mem.h"
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#include "avfft.h"
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/* FFT computation */
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struct FFTContext {
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    int nbits;
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    int inverse;
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    uint16_t *revtab;
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    FFTComplex *tmp_buf;
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    int mdct_size; /* size of MDCT (i.e. number of input data * 2) */
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    int mdct_bits; /* n = 2^nbits */
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    /* pre/post rotation tables */
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    FFTSample *tcos;
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    FFTSample *tsin;
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    void (*fft_permute)(struct FFTContext *s, FFTComplex *z);
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    void (*fft_calc)(struct FFTContext *s, FFTComplex *z);
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    void (*imdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
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    void (*imdct_half)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
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    void (*mdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
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    int permutation;
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#define FF_MDCT_PERM_NONE       0
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#define FF_MDCT_PERM_INTERLEAVE 1
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};
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#if CONFIG_HARDCODED_TABLES
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#define COSTABLE_CONST const
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#define SINTABLE_CONST const
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#define SINETABLE_CONST const
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#else
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#define COSTABLE_CONST
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#define SINTABLE_CONST
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#define SINETABLE_CONST
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#endif
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#define COSTABLE(size) \
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    COSTABLE_CONST DECLARE_ALIGNED(16, FFTSample, ff_cos_##size)[size/2]
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#define SINTABLE(size) \
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    SINTABLE_CONST DECLARE_ALIGNED(16, FFTSample, ff_sin_##size)[size/2]
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#define SINETABLE(size) \
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    SINETABLE_CONST DECLARE_ALIGNED(16, float, ff_sine_##size)[size]
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extern COSTABLE(16);
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extern COSTABLE(32);
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extern COSTABLE(64);
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extern COSTABLE(128);
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extern COSTABLE(256);
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extern COSTABLE(512);
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extern COSTABLE(1024);
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extern COSTABLE(2048);
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extern COSTABLE(4096);
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extern COSTABLE(8192);
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extern COSTABLE(16384);
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extern COSTABLE(32768);
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extern COSTABLE(65536);
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extern COSTABLE_CONST FFTSample* const ff_cos_tabs[17];
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/**
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 * Initialize the cosine table in ff_cos_tabs[index]
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 * \param index index in ff_cos_tabs array of the table to initialize
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 */
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void ff_init_ff_cos_tabs(int index);
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extern SINTABLE(16);
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extern SINTABLE(32);
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extern SINTABLE(64);
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extern SINTABLE(128);
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extern SINTABLE(256);
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extern SINTABLE(512);
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extern SINTABLE(1024);
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extern SINTABLE(2048);
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extern SINTABLE(4096);
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extern SINTABLE(8192);
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extern SINTABLE(16384);
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extern SINTABLE(32768);
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extern SINTABLE(65536);
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/**
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 * Set up a complex FFT.
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 * @param nbits           log2 of the length of the input array
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 * @param inverse         if 0 perform the forward transform, if 1 perform the inverse
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 */
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int ff_fft_init(FFTContext *s, int nbits, int inverse);
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void ff_fft_init_altivec(FFTContext *s);
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void ff_fft_init_mmx(FFTContext *s);
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void ff_fft_init_arm(FFTContext *s);
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void ff_dct_init_mmx(DCTContext *s);
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/**
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 * Do the permutation needed BEFORE calling ff_fft_calc().
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 */
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static inline void ff_fft_permute(FFTContext *s, FFTComplex *z)
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{
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    s->fft_permute(s, z);
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}
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/**
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 * Do a complex FFT with the parameters defined in ff_fft_init(). The
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 * input data must be permuted before. No 1.0/sqrt(n) normalization is done.
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 */
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static inline void ff_fft_calc(FFTContext *s, FFTComplex *z)
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{
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    s->fft_calc(s, z);
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}
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void ff_fft_end(FFTContext *s);
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/* MDCT computation */
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static inline void ff_imdct_calc(FFTContext *s, FFTSample *output, const FFTSample *input)
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{
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    s->imdct_calc(s, output, input);
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}
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static inline void ff_imdct_half(FFTContext *s, FFTSample *output, const FFTSample *input)
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{
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    s->imdct_half(s, output, input);
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}
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static inline void ff_mdct_calc(FFTContext *s, FFTSample *output,
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                                const FFTSample *input)
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{
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    s->mdct_calc(s, output, input);
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}
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/**
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 * Maximum window size for ff_kbd_window_init.
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 */
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#define FF_KBD_WINDOW_MAX 1024
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/**
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 * Generate a Kaiser-Bessel Derived Window.
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 * @param   window  pointer to half window
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 * @param   alpha   determines window shape
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 * @param   n       size of half window, max FF_KBD_WINDOW_MAX
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 */
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void ff_kbd_window_init(float *window, float alpha, int n);
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/**
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 * Generate a sine window.
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 * @param   window  pointer to half window
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 * @param   n       size of half window
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 */
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void ff_sine_window_init(float *window, int n);
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/**
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 * initialize the specified entry of ff_sine_windows
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 */
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void ff_init_ff_sine_windows(int index);
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extern SINETABLE(  32);
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extern SINETABLE(  64);
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extern SINETABLE( 128);
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extern SINETABLE( 256);
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extern SINETABLE( 512);
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extern SINETABLE(1024);
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extern SINETABLE(2048);
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extern SINETABLE(4096);
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extern SINETABLE_CONST float * const ff_sine_windows[13];
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int ff_mdct_init(FFTContext *s, int nbits, int inverse, double scale);
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void ff_imdct_calc_c(FFTContext *s, FFTSample *output, const FFTSample *input);
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void ff_imdct_half_c(FFTContext *s, FFTSample *output, const FFTSample *input);
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void ff_mdct_calc_c(FFTContext *s, FFTSample *output, const FFTSample *input);
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void ff_mdct_end(FFTContext *s);
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/* Real Discrete Fourier Transform */
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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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    SINTABLE_CONST FFTSample *tsin;
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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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static av_always_inline void ff_rdft_calc(RDFTContext *s, FFTSample *data)
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{
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    s->rdft_calc(s, data);
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}
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/* Discrete Cosine Transform */
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struct DCTContext {
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    int nbits;
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    int inverse;
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    RDFTContext rdft;
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    const float *costab;
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    FFTSample *csc2;
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    void (*dct_calc)(struct DCTContext *s, FFTSample *data);
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    void (*dct32)(FFTSample *out, const FFTSample *in);
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};
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/**
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 * Set up DCT.
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 * @param nbits           size of the input array:
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 *                        (1 << nbits)     for DCT-II, DCT-III and DST-I
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 *                        (1 << nbits) + 1 for DCT-I
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 *
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 * @note the first element of the input of DST-I is ignored
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 */
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int  ff_dct_init(DCTContext *s, int nbits, enum DCTTransformType type);
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void ff_dct_calc(DCTContext *s, FFTSample *data);
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void ff_dct_end (DCTContext *s);
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#endif /* AVCODEC_FFT_H */