FFmpeg
audiodsp.c
Go to the documentation of this file.
1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #include <stdint.h>
20 
21 #include "libavutil/attributes.h"
22 #include "libavutil/common.h"
23 #include "audiodsp.h"
24 
25 static inline uint32_t clipf_c_one(uint32_t a, uint32_t mini,
26  uint32_t maxi, uint32_t maxisign)
27 {
28  if (a > mini)
29  return mini;
30  else if ((a ^ (1U << 31)) > maxisign)
31  return maxi;
32  else
33  return a;
34 }
35 
36 static void vector_clipf_c_opposite_sign(float *dst, const float *src,
37  float *min, float *max, int len)
38 {
39  int i;
40  uint32_t mini = *(uint32_t *) min;
41  uint32_t maxi = *(uint32_t *) max;
42  uint32_t maxisign = maxi ^ (1U << 31);
43  uint32_t *dsti = (uint32_t *) dst;
44  const uint32_t *srci = (const uint32_t *) src;
45 
46  for (i = 0; i < len; i += 8) {
47  dsti[i + 0] = clipf_c_one(srci[i + 0], mini, maxi, maxisign);
48  dsti[i + 1] = clipf_c_one(srci[i + 1], mini, maxi, maxisign);
49  dsti[i + 2] = clipf_c_one(srci[i + 2], mini, maxi, maxisign);
50  dsti[i + 3] = clipf_c_one(srci[i + 3], mini, maxi, maxisign);
51  dsti[i + 4] = clipf_c_one(srci[i + 4], mini, maxi, maxisign);
52  dsti[i + 5] = clipf_c_one(srci[i + 5], mini, maxi, maxisign);
53  dsti[i + 6] = clipf_c_one(srci[i + 6], mini, maxi, maxisign);
54  dsti[i + 7] = clipf_c_one(srci[i + 7], mini, maxi, maxisign);
55  }
56 }
57 
58 static void vector_clipf_c(float *dst, const float *src, int len,
59  float min, float max)
60 {
61  int i;
62 
63  if (min < 0 && max > 0) {
64  vector_clipf_c_opposite_sign(dst, src, &min, &max, len);
65  } else {
66  for (i = 0; i < len; i += 8) {
67  dst[i] = av_clipf(src[i], min, max);
68  dst[i + 1] = av_clipf(src[i + 1], min, max);
69  dst[i + 2] = av_clipf(src[i + 2], min, max);
70  dst[i + 3] = av_clipf(src[i + 3], min, max);
71  dst[i + 4] = av_clipf(src[i + 4], min, max);
72  dst[i + 5] = av_clipf(src[i + 5], min, max);
73  dst[i + 6] = av_clipf(src[i + 6], min, max);
74  dst[i + 7] = av_clipf(src[i + 7], min, max);
75  }
76  }
77 }
78 
79 static int32_t scalarproduct_int16_c(const int16_t *v1, const int16_t *v2,
80  int order)
81 {
82  int res = 0;
83 
84  while (order--)
85  res += *v1++ **v2++;
86 
87  return res;
88 }
89 
90 static void vector_clip_int32_c(int32_t *dst, const int32_t *src, int32_t min,
91  int32_t max, unsigned int len)
92 {
93  do {
94  *dst++ = av_clip(*src++, min, max);
95  *dst++ = av_clip(*src++, min, max);
96  *dst++ = av_clip(*src++, min, max);
97  *dst++ = av_clip(*src++, min, max);
98  *dst++ = av_clip(*src++, min, max);
99  *dst++ = av_clip(*src++, min, max);
100  *dst++ = av_clip(*src++, min, max);
101  *dst++ = av_clip(*src++, min, max);
102  len -= 8;
103  } while (len > 0);
104 }
105 
107 {
111 
112  if (ARCH_ARM)
114  if (ARCH_PPC)
116  if (ARCH_X86)
118 }
static void vector_clipf_c_opposite_sign(float *dst, const float *src, float *min, float *max, int len)
Definition: audiodsp.c:36
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:36
#define src
Definition: vp8dsp.c:254
static void vector_clipf_c(float *dst, const float *src, int len, float min, float max)
Definition: audiodsp.c:58
Macro definitions for various function/variable attributes.
av_cold void ff_audiodsp_init_arm(AudioDSPContext *c)
void(* vector_clip_int32)(int32_t *dst, const int32_t *src, int32_t min, int32_t max, unsigned int len)
Clip each element in an array of int32_t to a given minimum and maximum value.
Definition: audiodsp.h:46
#define av_cold
Definition: attributes.h:82
av_cold void ff_audiodsp_init(AudioDSPContext *c)
Definition: audiodsp.c:106
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
void(* vector_clipf)(float *dst, const float *src, int len, float min, float max)
Definition: audiodsp.h:49
av_cold void ff_audiodsp_init_ppc(AudioDSPContext *c)
Definition: audiodsp.c:86
#define max(a, b)
Definition: cuda_runtime.h:33
static uint32_t clipf_c_one(uint32_t a, uint32_t mini, uint32_t maxi, uint32_t maxisign)
Definition: audiodsp.c:25
#define U(x)
Definition: vp56_arith.h:37
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
int32_t
static int32_t scalarproduct_int16_c(const int16_t *v1, const int16_t *v2, int order)
Definition: audiodsp.c:79
int32_t(* scalarproduct_int16)(const int16_t *v1, const int16_t *v2, int len)
Calculate scalar product of two vectors.
Definition: audiodsp.h:29
common internal and external API header
int len
static void vector_clip_int32_c(int32_t *dst, const int32_t *src, int32_t min, int32_t max, unsigned int len)
Definition: audiodsp.c:90
float min
void ff_audiodsp_init_x86(AudioDSPContext *c)
Definition: audiodsp_init.c:43