FFmpeg: libavcodec/audiodsp.c Source File

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libavcodec

audiodsp.c

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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 */

19 #include <stdint.h>

21 #include "libavutil/attributes.h"

22 #include "libavutil/common.h"

23 #include "audiodsp.h"

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 }

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;

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 }

58 static void vector_clipf_c(float *dst, const float *src, int len,

59 float min, float max)

60 {

61 int i;

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 }

79 static int32_t scalarproduct_int16_c(const int16_t *v1, const int16_t *v2,

80 int order)

81 {

82 unsigned res = 0;

84 while (order--)

85 res += *v1++ **v2++;

87 return res;

88 }

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

106 av_cold void ff_audiodsp_init(AudioDSPContext *c)

107 {

108 c->scalarproduct_int16 = scalarproduct_int16_c;

109 c->vector_clip_int32 = vector_clip_int32_c;

110 c->vector_clipf = vector_clipf_c;

111

112 if (ARCH_ARM)

113 ff_audiodsp_init_arm(c);

114 if (ARCH_PPC)

115 ff_audiodsp_init_ppc(c);

116 if (ARCH_X86)

117 ff_audiodsp_init_x86(c);

118 }

av_clip

#define av_clip

Definition: common.h:96

vector_clipf_c_opposite_sign

static void vector_clipf_c_opposite_sign(float *dst, const float *src, float *min, float *max, int len)

Definition: audiodsp.c:36

ff_audiodsp_init_x86

void ff_audiodsp_init_x86(AudioDSPContext *c)

Definition: audiodsp_init.c:43

ff_audiodsp_init

av_cold void ff_audiodsp_init(AudioDSPContext *c)

Definition: audiodsp.c:106

max

#define max(a, b)

Definition: cuda_runtime.h:33

ff_audiodsp_init_ppc

av_cold void ff_audiodsp_init_ppc(AudioDSPContext *c)

Definition: audiodsp.c:86

clipf_c_one

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

av_cold

#define av_cold

Definition: attributes.h:90

vector_clipf_c

static void vector_clipf_c(float *dst, const float *src, int len, float min, float max)

Definition: audiodsp.c:58

ff_audiodsp_init_arm

av_cold void ff_audiodsp_init_arm(AudioDSPContext *c)

Definition: audiodsp_init_arm.c:27

av_clipf

#define av_clipf

Definition: common.h:144

src

#define src

Definition: vp8dsp.c:255

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

vector_clip_int32_c

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

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:41

attributes.h

#define i(width, name, range_min, range_max)

Definition: cbs_h2645.c:271

common.h

len

int len

Definition: vorbis_enc_data.h:426

scalarproduct_int16_c

static int32_t scalarproduct_int16_c(const int16_t *v1, const int16_t *v2, int order)

Definition: audiodsp.c:79

audiodsp.h