FFmpeg
mdct15_init.c
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1 /*
2  * SIMD optimized non-power-of-two MDCT functions
3  *
4  * Copyright (C) 2017 Rostislav Pehlivanov <atomnuker@gmail.com>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include <string.h>
24 
25 #include "config.h"
26 
27 #include "libavutil/attributes.h"
28 #include "libavutil/x86/cpu.h"
29 #include "libavcodec/mdct15.h"
30 
31 void ff_mdct15_postreindex_sse3(FFTComplex *out, FFTComplex *in, FFTComplex *exp, int *lut, ptrdiff_t len8);
32 void ff_mdct15_postreindex_avx2(FFTComplex *out, FFTComplex *in, FFTComplex *exp, int *lut, ptrdiff_t len8);
33 
35 
37 {
38  int k;
39  FFTComplex tmp[30];
40 
41  /* 5-point FFT twiddles */
42  s->exptab[60].re = s->exptab[60].im = s->exptab[19].re;
43  s->exptab[61].re = s->exptab[61].im = s->exptab[19].im;
44  s->exptab[62].re = s->exptab[62].im = s->exptab[20].re;
45  s->exptab[63].re = s->exptab[63].im = s->exptab[20].im;
46 
47  /* 15-point FFT twiddles */
48  for (k = 0; k < 5; k++) {
49  tmp[6*k + 0] = s->exptab[k + 0];
50  tmp[6*k + 2] = s->exptab[k + 5];
51  tmp[6*k + 4] = s->exptab[k + 10];
52 
53  tmp[6*k + 1] = s->exptab[2 * (k + 0)];
54  tmp[6*k + 3] = s->exptab[2 * (k + 5)];
55  tmp[6*k + 5] = s->exptab[2 * k + 5 ];
56  }
57 
58  for (k = 0; k < 6; k++) {
59  FFTComplex ac_exp[] = {
60  { tmp[6*1 + k].re, tmp[6*1 + k].re },
61  { tmp[6*2 + k].re, tmp[6*2 + k].re },
62  { tmp[6*3 + k].re, tmp[6*3 + k].re },
63  { tmp[6*4 + k].re, tmp[6*4 + k].re },
64  { tmp[6*1 + k].im, -tmp[6*1 + k].im },
65  { tmp[6*2 + k].im, -tmp[6*2 + k].im },
66  { tmp[6*3 + k].im, -tmp[6*3 + k].im },
67  { tmp[6*4 + k].im, -tmp[6*4 + k].im },
68  };
69  memcpy(s->exptab + 8*k, ac_exp, 8*sizeof(FFTComplex));
70  }
71 
72  /* Specialcase when k = 0 */
73  for (k = 0; k < 3; k++) {
74  FFTComplex dc_exp[] = {
75  { tmp[2*k + 0].re, -tmp[2*k + 0].im },
76  { tmp[2*k + 0].im, tmp[2*k + 0].re },
77  { tmp[2*k + 1].re, -tmp[2*k + 1].im },
78  { tmp[2*k + 1].im, tmp[2*k + 1].re },
79  };
80  memcpy(s->exptab + 8*6 + 4*k, dc_exp, 4*sizeof(FFTComplex));
81  }
82 }
83 
85 {
86  int adjust_twiddles = 0;
88 
90  s->postreindex = ff_mdct15_postreindex_sse3;
91 
92 #if ARCH_X86_64
93  if (EXTERNAL_AVX(cpu_flags)) {
94  s->fft15 = ff_fft15_avx;
95  adjust_twiddles = 1;
96  }
97 
99  s->postreindex = ff_mdct15_postreindex_avx2;
100 #endif
101 
102  if (adjust_twiddles)
103  perm_twiddles(s);
104 }
cpu.h
out
FILE * out
Definition: movenc.c:54
ff_mdct15_postreindex_avx2
void ff_mdct15_postreindex_avx2(FFTComplex *out, FFTComplex *in, FFTComplex *exp, int *lut, ptrdiff_t len8)
EXTERNAL_AVX2_FAST
#define EXTERNAL_AVX2_FAST(flags)
Definition: cpu.h:79
tmp
static uint8_t tmp[11]
Definition: aes_ctr.c:28
mdct15.h
av_get_cpu_flags
int av_get_cpu_flags(void)
Return the flags which specify extensions supported by the CPU.
Definition: cpu.c:101
perm_twiddles
static void perm_twiddles(MDCT15Context *s)
Definition: mdct15_init.c:36
cpu_flags
static atomic_int cpu_flags
Definition: cpu.c:52
av_cold
#define av_cold
Definition: attributes.h:90
s
#define s(width, name)
Definition: cbs_vp9.c:256
MDCT15Context
Definition: mdct15.h:30
EXTERNAL_SSE3
#define EXTERNAL_SSE3(flags)
Definition: cpu.h:62
exp
int8_t exp
Definition: eval.c:72
exptab
static struct @140 * exptab
ff_mdct15_init_x86
av_cold void ff_mdct15_init_x86(MDCT15Context *s)
Definition: mdct15_init.c:84
attributes.h
ff_mdct15_postreindex_sse3
void ff_mdct15_postreindex_sse3(FFTComplex *out, FFTComplex *in, FFTComplex *exp, int *lut, ptrdiff_t len8)
stride
#define stride
Definition: h264pred_template.c:537
ff_fft15_avx
void ff_fft15_avx(FFTComplex *out, FFTComplex *in, FFTComplex *exptab, ptrdiff_t stride)
EXTERNAL_AVX
#define EXTERNAL_AVX(flags)
Definition: cpu.h:70
FFTComplex
Definition: avfft.h:37