FFmpeg  4.0
resample_init.c
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1 /*
2  * Audio resampling
3  *
4  * Copyright (c) 2004-2012 Michael Niedermayer <michaelni@gmx.at>
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 "config.h"
24 
25 #include "libavutil/cpu.h"
26 #include "libavutil/avassert.h"
27 
28 #include "libavutil/arm/cpu.h"
29 #include "libswresample/resample.h"
30 
31 #define DECLARE_RESAMPLE_COMMON_TEMPLATE(TYPE, DELEM, FELEM, FELEM2, OUT) \
32  \
33 void ff_resample_common_apply_filter_x4_##TYPE##_neon(FELEM2 *acc, const DELEM *src, \
34  const FELEM *filter, int length); \
35  \
36 void ff_resample_common_apply_filter_x8_##TYPE##_neon(FELEM2 *acc, const DELEM *src, \
37  const FELEM *filter, int length); \
38  \
39 static int ff_resample_common_##TYPE##_neon(ResampleContext *c, void *dest, const void *source, \
40  int n, int update_ctx) \
41 { \
42  DELEM *dst = dest; \
43  const DELEM *src = source; \
44  int dst_index; \
45  int index = c->index; \
46  int frac = c->frac; \
47  int sample_index = 0; \
48  int x4_aligned_filter_length = c->filter_length & ~3; \
49  int x8_aligned_filter_length = c->filter_length & ~7; \
50  \
51  while (index >= c->phase_count) { \
52  sample_index++; \
53  index -= c->phase_count; \
54  } \
55  \
56  for (dst_index = 0; dst_index < n; dst_index++) { \
57  FELEM *filter = ((FELEM *) c->filter_bank) + c->filter_alloc * index; \
58  \
59  FELEM2 val = 0; \
60  int i = 0; \
61  if (x8_aligned_filter_length >= 8) { \
62  ff_resample_common_apply_filter_x8_##TYPE##_neon(&val, &src[sample_index], \
63  filter, x8_aligned_filter_length); \
64  i += x8_aligned_filter_length; \
65  \
66  } else if (x4_aligned_filter_length >= 4) { \
67  ff_resample_common_apply_filter_x4_##TYPE##_neon(&val, &src[sample_index], \
68  filter, x4_aligned_filter_length); \
69  i += x4_aligned_filter_length; \
70  } \
71  for (; i < c->filter_length; i++) { \
72  val += src[sample_index + i] * (FELEM2)filter[i]; \
73  } \
74  OUT(dst[dst_index], val); \
75  \
76  frac += c->dst_incr_mod; \
77  index += c->dst_incr_div; \
78  if (frac >= c->src_incr) { \
79  frac -= c->src_incr; \
80  index++; \
81  } \
82  \
83  while (index >= c->phase_count) { \
84  sample_index++; \
85  index -= c->phase_count; \
86  } \
87  } \
88  \
89  if (update_ctx) { \
90  c->frac = frac; \
91  c->index = index; \
92  } \
93  \
94  return sample_index; \
95 } \
96 
97 #define OUT(d, v) d = v
98 DECLARE_RESAMPLE_COMMON_TEMPLATE(float, float, float, float, OUT)
99 #undef OUT
100 
101 #define OUT(d, v) (v) = ((v) + (1<<(14)))>>15; (d) = av_clip_int16(v)
102 DECLARE_RESAMPLE_COMMON_TEMPLATE(s16, int16_t, int16_t, int32_t, OUT)
103 #undef OUT
104 
105 av_cold void swri_resample_dsp_arm_init(ResampleContext *c)
106 {
107  int cpu_flags = av_get_cpu_flags();
108 
109  if (!have_neon(cpu_flags))
110  return;
111 
112  switch(c->format) {
113  case AV_SAMPLE_FMT_FLTP:
114  c->dsp.resample_common = ff_resample_common_float_neon;
115  break;
116  case AV_SAMPLE_FMT_S16P:
117  c->dsp.resample_common = ff_resample_common_s16_neon;
118  break;
119  }
120 }
AV_SAMPLE_FMT_FLTP
float, planar
Definition: samplefmt.h:69
cpu_flags
static atomic_int cpu_flags
Definition: cpu.c:50
OUT
#define OUT(d, v)
Definition: resample_init.c:101
swri_resample_dsp_arm_init
av_cold void swri_resample_dsp_arm_init(ResampleContext *c)
Definition: resample_init.c:105
ResampleContext::format
enum AVSampleFormat format
Definition: resample.h:48
av_cold
#define av_cold
Definition: attributes.h:82
avassert.h
simple assert() macros that are a bit more flexible than ISO C assert().
have_neon
#define have_neon(flags)
Definition: cpu.h:26
ResampleContext::dsp
struct ResampleContext::@267 dsp
ResampleContext::resample_common
int(* resample_common)(struct ResampleContext *c, void *dst, const void *src, int n, int update_ctx)
Definition: resample.h:56
int32_t
int32_t
Definition: audio_convert.c:194
av_get_cpu_flags
int av_get_cpu_flags(void)
Return the flags which specify extensions supported by the CPU.
Definition: cpu.c:93
c
static double c[64]
Definition: vsrc_mptestsrc.c:87
AV_SAMPLE_FMT_S16P
signed 16 bits, planar
Definition: samplefmt.h:67
DECLARE_RESAMPLE_COMMON_TEMPLATE
#define DECLARE_RESAMPLE_COMMON_TEMPLATE(TYPE, DELEM, FELEM, FELEM2, OUT)
Definition: resample_init.c:31
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