FFmpeg: libavcodec/jpeg2000dsp.c Source File

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jpeg2000dsp.c

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1 /*

2 * JPEG 2000 DSP functions

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 */

23 #include "config.h"

24 #include "libavutil/attributes.h"

25 #include "jpeg2000dsp.h"

27 /* Inverse ICT parameters in float and integer.

28 * int value = (float value) * (1<<16) */

29 static const float f_ict_params[4] = {

30 1.402f,

31 0.34413f,

32 0.71414f,

33 1.772f

34 };

36 static const int i_ict_params[4] = {

37 91881,

38 22553,

39 46802,

40 116130

41 };

43 static void ict_float(void *_src0, void *_src1, void *_src2, int csize)

44 {

45 float *src0 = _src0, *src1 = _src1, *src2 = _src2;

46 float i0f, i1f, i2f;

47 int i;

49 for (i = 0; i < csize; i++) {

50 i0f = *src0 + (f_ict_params[0] * *src2);

51 i1f = *src0 - (f_ict_params[1] * *src1)

52 - (f_ict_params[2] * *src2);

53 i2f = *src0 + (f_ict_params[3] * *src1);

54 *src0++ = i0f;

55 *src1++ = i1f;

56 *src2++ = i2f;

57 }

58 }

60 static void ict_int(void *_src0, void *_src1, void *_src2, int csize)

61 {

62 int32_t *src0 = _src0, *src1 = _src1, *src2 = _src2;

63 int32_t i0, i1, i2;

64 int i;

66 for (i = 0; i < csize; i++) {

67 i0 = *src0 + *src2 + ((int)((26345U * *src2) + (1 << 15)) >> 16);

68 i1 = *src0 - ((int)(((unsigned)i_ict_params[1] * *src1) + (1 << 15)) >> 16)

69 - ((int)(((unsigned)i_ict_params[2] * *src2) + (1 << 15)) >> 16);

70 i2 = *src0 + (2 * *src1) + ((int)((-14942U * *src1) + (1 << 15)) >> 16);

71 *src0++ = i0;

72 *src1++ = i1;

73 *src2++ = i2;

74 }

75 }

77 static void rct_int(void *_src0, void *_src1, void *_src2, int csize)

78 {

79 int32_t *src0 = _src0, *src1 = _src1, *src2 = _src2;

80 int32_t i0, i1, i2;

81 int i;

83 for (i = 0; i < csize; i++) {

84 i1 = *src0 - (*src2 + *src1 >> 2);

85 i0 = i1 + *src2;

86 i2 = i1 + *src1;

87 *src0++ = i0;

88 *src1++ = i1;

89 *src2++ = i2;

90 }

91 }

93 av_cold void ff_jpeg2000dsp_init(Jpeg2000DSPContext *c)

94 {

95 c->mct_decode[FF_DWT97] = ict_float;

96 c->mct_decode[FF_DWT53] = rct_int;

97 c->mct_decode[FF_DWT97_INT] = ict_int;

99 if (ARCH_X86)

100 ff_jpeg2000dsp_init_x86(c);

101 }

ict_float

static void ict_float(void *_src0, void *_src1, void *_src2, int csize)

Definition: jpeg2000dsp.c:43

ff_jpeg2000dsp_init_x86

void ff_jpeg2000dsp_init_x86(Jpeg2000DSPContext *c)

Definition: jpeg2000dsp_init.c:34

FF_DWT97

@ FF_DWT97

Definition: jpeg2000dwt.h:37

#define U(x)

Definition: vp56_arith.h:37

av_cold

#define av_cold

Definition: attributes.h:90

ict_int

static void ict_int(void *_src0, void *_src1, void *_src2, int csize)

Definition: jpeg2000dsp.c:60

ff_jpeg2000dsp_init

av_cold void ff_jpeg2000dsp_init(Jpeg2000DSPContext *c)

Definition: jpeg2000dsp.c:93

Jpeg2000DSPContext

Definition: jpeg2000dsp.h:29

i_ict_params

static const int i_ict_params[4]

Definition: jpeg2000dsp.c:36

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

i2f

static Float11 * i2f(int i, Float11 *f)

Definition: g726.c:46

attributes.h

src0

#define src0

Definition: h264pred.c:139

src1

#define src1

Definition: h264pred.c:140

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