/* * Copyright (c) 2000, 2001, 2002 Fabrice Bellard * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at> * * This file is part of Libav. * * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Libav 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef AVCODEC_FFT_H #define AVCODEC_FFT_H #ifndef FFT_FLOAT #define FFT_FLOAT 1 #endif #include <stdint.h> #include "config.h" #include "libavutil/mem.h" #if FFT_FLOAT #include "avfft.h" #define FFT_NAME(x) x typedef float FFTDouble; #else #define FFT_NAME(x) x ## _fixed typedef int16_t FFTSample; typedef int FFTDouble; typedef struct FFTComplex { int16_t re, im; } FFTComplex; typedef struct FFTContext FFTContext; #endif /* FFT_FLOAT */ typedef struct FFTDComplex { FFTDouble re, im; } FFTDComplex; /* FFT computation */ enum fft_permutation_type { FF_FFT_PERM_DEFAULT, FF_FFT_PERM_SWAP_LSBS, FF_FFT_PERM_AVX, }; enum mdct_permutation_type { FF_MDCT_PERM_NONE, FF_MDCT_PERM_INTERLEAVE, }; struct FFTContext { int nbits; int inverse; uint16_t *revtab; FFTComplex *tmp_buf; int mdct_size; /* size of MDCT (i.e. number of input data * 2) */ int mdct_bits; /* n = 2^nbits */ /* pre/post rotation tables */ FFTSample *tcos; FFTSample *tsin; /** * Do the permutation needed BEFORE calling fft_calc(). */ void (*fft_permute)(struct FFTContext *s, FFTComplex *z); /** * Do a complex FFT with the parameters defined in ff_fft_init(). The * input data must be permuted before. No 1.0/sqrt(n) normalization is done. */ void (*fft_calc)(struct FFTContext *s, FFTComplex *z); void (*imdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input); void (*imdct_half)(struct FFTContext *s, FFTSample *output, const FFTSample *input); void (*mdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input); void (*mdct_calcw)(struct FFTContext *s, FFTDouble *output, const FFTSample *input); enum fft_permutation_type fft_permutation; enum mdct_permutation_type mdct_permutation; }; #if CONFIG_HARDCODED_TABLES #define COSTABLE_CONST const #else #define COSTABLE_CONST #endif #define COSTABLE(size) \ COSTABLE_CONST DECLARE_ALIGNED(32, FFTSample, FFT_NAME(ff_cos_##size))[size/2] extern COSTABLE(16); extern COSTABLE(32); extern COSTABLE(64); extern COSTABLE(128); extern COSTABLE(256); extern COSTABLE(512); extern COSTABLE(1024); extern COSTABLE(2048); extern COSTABLE(4096); extern COSTABLE(8192); extern COSTABLE(16384); extern COSTABLE(32768); extern COSTABLE(65536); extern COSTABLE_CONST FFTSample* const FFT_NAME(ff_cos_tabs)[17]; #define ff_init_ff_cos_tabs FFT_NAME(ff_init_ff_cos_tabs) /** * Initialize the cosine table in ff_cos_tabs[index] * @param index index in ff_cos_tabs array of the table to initialize */ void ff_init_ff_cos_tabs(int index); #define ff_fft_init FFT_NAME(ff_fft_init) #define ff_fft_end FFT_NAME(ff_fft_end) /** * Set up a complex FFT. * @param nbits log2 of the length of the input array * @param inverse if 0 perform the forward transform, if 1 perform the inverse */ int ff_fft_init(FFTContext *s, int nbits, int inverse); void ff_fft_init_aarch64(FFTContext *s); void ff_fft_init_x86(FFTContext *s); void ff_fft_init_arm(FFTContext *s); void ff_fft_init_ppc(FFTContext *s); void ff_fft_fixed_init_arm(FFTContext *s); void ff_fft_end(FFTContext *s); #define ff_mdct_init FFT_NAME(ff_mdct_init) #define ff_mdct_end FFT_NAME(ff_mdct_end) int ff_mdct_init(FFTContext *s, int nbits, int inverse, double scale); void ff_mdct_end(FFTContext *s); #endif /* AVCODEC_FFT_H */