| 1 | /* |
| 2 | * Copyright (c) 2000, 2001, 2002 Fabrice Bellard |
| 3 | * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at> |
| 4 | * |
| 5 | * This file is part of FFmpeg. |
| 6 | * |
| 7 | * FFmpeg is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU Lesser General Public |
| 9 | * License as published by the Free Software Foundation; either |
| 10 | * version 2.1 of the License, or (at your option) any later version. |
| 11 | * |
| 12 | * FFmpeg is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * Lesser General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU Lesser General Public |
| 18 | * License along with FFmpeg; if not, write to the Free Software |
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 20 | */ |
| 21 | |
| 22 | #ifndef AVCODEC_FFT_H |
| 23 | #define AVCODEC_FFT_H |
| 24 | |
| 25 | #ifndef FFT_FLOAT |
| 26 | #define FFT_FLOAT 1 |
| 27 | #endif |
| 28 | |
| 29 | #ifndef FFT_FIXED_32 |
| 30 | #define FFT_FIXED_32 0 |
| 31 | #endif |
| 32 | |
| 33 | #include <stdint.h> |
| 34 | #include "config.h" |
| 35 | #include "libavutil/mem.h" |
| 36 | |
| 37 | #if FFT_FLOAT |
| 38 | |
| 39 | #include "avfft.h" |
| 40 | |
| 41 | #define FFT_NAME(x) x |
| 42 | |
| 43 | typedef float FFTDouble; |
| 44 | |
| 45 | #else |
| 46 | |
| 47 | #if FFT_FIXED_32 |
| 48 | |
| 49 | #define Q31(x) (int)((x)*2147483648.0 + 0.5) |
| 50 | #define FFT_NAME(x) x ## _fixed_32 |
| 51 | |
| 52 | typedef int32_t FFTSample; |
| 53 | |
| 54 | #else /* FFT_FIXED_32 */ |
| 55 | |
| 56 | #define FFT_NAME(x) x ## _fixed |
| 57 | |
| 58 | typedef int16_t FFTSample; |
| 59 | |
| 60 | #endif /* FFT_FIXED_32 */ |
| 61 | |
| 62 | typedef struct FFTComplex { |
| 63 | FFTSample re, im; |
| 64 | } FFTComplex; |
| 65 | |
| 66 | typedef int FFTDouble; |
| 67 | typedef struct FFTContext FFTContext; |
| 68 | |
| 69 | #endif /* FFT_FLOAT */ |
| 70 | |
| 71 | typedef struct FFTDComplex { |
| 72 | FFTDouble re, im; |
| 73 | } FFTDComplex; |
| 74 | |
| 75 | /* FFT computation */ |
| 76 | |
| 77 | enum fft_permutation_type { |
| 78 | FF_FFT_PERM_DEFAULT, |
| 79 | FF_FFT_PERM_SWAP_LSBS, |
| 80 | FF_FFT_PERM_AVX, |
| 81 | }; |
| 82 | |
| 83 | enum mdct_permutation_type { |
| 84 | FF_MDCT_PERM_NONE, |
| 85 | FF_MDCT_PERM_INTERLEAVE, |
| 86 | }; |
| 87 | |
| 88 | struct FFTContext { |
| 89 | int nbits; |
| 90 | int inverse; |
| 91 | uint16_t *revtab; |
| 92 | FFTComplex *tmp_buf; |
| 93 | int mdct_size; /* size of MDCT (i.e. number of input data * 2) */ |
| 94 | int mdct_bits; /* n = 2^nbits */ |
| 95 | /* pre/post rotation tables */ |
| 96 | FFTSample *tcos; |
| 97 | FFTSample *tsin; |
| 98 | /** |
| 99 | * Do the permutation needed BEFORE calling fft_calc(). |
| 100 | */ |
| 101 | void (*fft_permute)(struct FFTContext *s, FFTComplex *z); |
| 102 | /** |
| 103 | * Do a complex FFT with the parameters defined in ff_fft_init(). The |
| 104 | * input data must be permuted before. No 1.0/sqrt(n) normalization is done. |
| 105 | */ |
| 106 | void (*fft_calc)(struct FFTContext *s, FFTComplex *z); |
| 107 | void (*imdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input); |
| 108 | void (*imdct_half)(struct FFTContext *s, FFTSample *output, const FFTSample *input); |
| 109 | void (*mdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input); |
| 110 | void (*mdct_calcw)(struct FFTContext *s, FFTDouble *output, const FFTSample *input); |
| 111 | enum fft_permutation_type fft_permutation; |
| 112 | enum mdct_permutation_type mdct_permutation; |
| 113 | }; |
| 114 | |
| 115 | #if CONFIG_HARDCODED_TABLES |
| 116 | #define COSTABLE_CONST const |
| 117 | #else |
| 118 | #define COSTABLE_CONST |
| 119 | #endif |
| 120 | |
| 121 | #define COSTABLE(size) \ |
| 122 | COSTABLE_CONST DECLARE_ALIGNED(32, FFTSample, FFT_NAME(ff_cos_##size))[size/2] |
| 123 | |
| 124 | extern COSTABLE(16); |
| 125 | extern COSTABLE(32); |
| 126 | extern COSTABLE(64); |
| 127 | extern COSTABLE(128); |
| 128 | extern COSTABLE(256); |
| 129 | extern COSTABLE(512); |
| 130 | extern COSTABLE(1024); |
| 131 | extern COSTABLE(2048); |
| 132 | extern COSTABLE(4096); |
| 133 | extern COSTABLE(8192); |
| 134 | extern COSTABLE(16384); |
| 135 | extern COSTABLE(32768); |
| 136 | extern COSTABLE(65536); |
| 137 | extern COSTABLE_CONST FFTSample* const FFT_NAME(ff_cos_tabs)[17]; |
| 138 | |
| 139 | #define ff_init_ff_cos_tabs FFT_NAME(ff_init_ff_cos_tabs) |
| 140 | |
| 141 | /** |
| 142 | * Initialize the cosine table in ff_cos_tabs[index] |
| 143 | * @param index index in ff_cos_tabs array of the table to initialize |
| 144 | */ |
| 145 | void ff_init_ff_cos_tabs(int index); |
| 146 | |
| 147 | #define ff_fft_init FFT_NAME(ff_fft_init) |
| 148 | #define ff_fft_end FFT_NAME(ff_fft_end) |
| 149 | |
| 150 | /** |
| 151 | * Set up a complex FFT. |
| 152 | * @param nbits log2 of the length of the input array |
| 153 | * @param inverse if 0 perform the forward transform, if 1 perform the inverse |
| 154 | */ |
| 155 | int ff_fft_init(FFTContext *s, int nbits, int inverse); |
| 156 | |
| 157 | void ff_fft_init_aarch64(FFTContext *s); |
| 158 | void ff_fft_init_x86(FFTContext *s); |
| 159 | void ff_fft_init_arm(FFTContext *s); |
| 160 | void ff_fft_init_mips(FFTContext *s); |
| 161 | void ff_fft_init_ppc(FFTContext *s); |
| 162 | |
| 163 | void ff_fft_fixed_init_arm(FFTContext *s); |
| 164 | |
| 165 | void ff_fft_end(FFTContext *s); |
| 166 | |
| 167 | #define ff_mdct_init FFT_NAME(ff_mdct_init) |
| 168 | #define ff_mdct_end FFT_NAME(ff_mdct_end) |
| 169 | |
| 170 | int ff_mdct_init(FFTContext *s, int nbits, int inverse, double scale); |
| 171 | void ff_mdct_end(FFTContext *s); |
| 172 | |
| 173 | #endif /* AVCODEC_FFT_H */ |