FFmpeg: libavcodec/flacdsp.c Source File

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libavcodec

flacdsp.c

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1 /*

3 *

4 * This file is part of FFmpeg.

5 *

6 * FFmpeg is free software; you can redistribute it and/or

7 * modify it under the terms of the GNU Lesser General Public

8 * License as published by the Free Software Foundation; either

9 * version 2.1 of the License, or (at your option) any later version.

10 *

11 * FFmpeg is distributed in the hope that it will be useful,

12 * but WITHOUT ANY WARRANTY; without even the implied warranty of

13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

14 * Lesser General Public License for more details.

15 *

16 * You should have received a copy of the GNU Lesser General Public

17 * License along with FFmpeg; if not, write to the Free Software

18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

19 */

21 #include "libavutil/attributes.h"

22 #include "libavutil/internal.h"

23 #include "libavutil/samplefmt.h"

24 #include "flacdsp.h"

25 #include "config.h"

27 #define SAMPLE_SIZE 16

28 #define PLANAR 0

29 #include "flacdsp_template.c"

30 #include "flacdsp_lpc_template.c"

32 #undef PLANAR

33 #define PLANAR 1

34 #include "flacdsp_template.c"

36 #undef SAMPLE_SIZE

37 #undef PLANAR

38 #define SAMPLE_SIZE 32

39 #define PLANAR 0

40 #include "flacdsp_template.c"

41 #include "flacdsp_lpc_template.c"

43 #undef PLANAR

44 #define PLANAR 1

45 #include "flacdsp_template.c"

47 static void flac_lpc_16_c(int32_t *decoded, const int coeffs[32],

48 int pred_order, int qlevel, int len)

49 {

50 int i, j;

52 for (i = pred_order; i < len - 1; i += 2, decoded += 2) {

53 SUINT c = coeffs[0];

54 SUINT d = decoded[0];

55 int s0 = 0, s1 = 0;

56 for (j = 1; j < pred_order; j++) {

57 s0 += c*d;

58 d = decoded[j];

59 s1 += c*d;

60 c = coeffs[j];

61 }

62 s0 += c*d;

63 d = decoded[j] += (SUINT)(s0 >> qlevel);

64 s1 += c*d;

65 decoded[j + 1] += (SUINT)(s1 >> qlevel);

66 }

67 if (i < len) {

68 int sum = 0;

69 for (j = 0; j < pred_order; j++)

70 sum += coeffs[j] * (SUINT)decoded[j];

71 decoded[j] = decoded[j] + (unsigned)(sum >> qlevel);

72 }

73 }

75 static void flac_lpc_32_c(int32_t *decoded, const int coeffs[32],

76 int pred_order, int qlevel, int len)

77 {

78 int i, j;

80 for (i = pred_order; i < len; i++, decoded++) {

81 int64_t sum = 0;

82 for (j = 0; j < pred_order; j++)

83 sum += (int64_t)coeffs[j] * decoded[j];

84 decoded[j] += sum >> qlevel;

85 }

87 }

89 av_cold void ff_flacdsp_init(FLACDSPContext *c, enum AVSampleFormat fmt, int channels,

90 int bps)

91 {

92 c->lpc16 = flac_lpc_16_c;

93 c->lpc32 = flac_lpc_32_c;

94 c->lpc16_encode = flac_lpc_encode_c_16;

95 c->lpc32_encode = flac_lpc_encode_c_32;

97 switch (fmt) {

98 case AV_SAMPLE_FMT_S32:

99 c->decorrelate[0] = flac_decorrelate_indep_c_32;

100 c->decorrelate[1] = flac_decorrelate_ls_c_32;

101 c->decorrelate[2] = flac_decorrelate_rs_c_32;

102 c->decorrelate[3] = flac_decorrelate_ms_c_32;

103 break;

104

105 case AV_SAMPLE_FMT_S32P:

106 c->decorrelate[0] = flac_decorrelate_indep_c_32p;

107 c->decorrelate[1] = flac_decorrelate_ls_c_32p;

108 c->decorrelate[2] = flac_decorrelate_rs_c_32p;

109 c->decorrelate[3] = flac_decorrelate_ms_c_32p;

110 break;

111

112 case AV_SAMPLE_FMT_S16:

113 c->decorrelate[0] = flac_decorrelate_indep_c_16;

114 c->decorrelate[1] = flac_decorrelate_ls_c_16;

115 c->decorrelate[2] = flac_decorrelate_rs_c_16;

116 c->decorrelate[3] = flac_decorrelate_ms_c_16;

117 break;

118

119 case AV_SAMPLE_FMT_S16P:

120 c->decorrelate[0] = flac_decorrelate_indep_c_16p;

121 c->decorrelate[1] = flac_decorrelate_ls_c_16p;

122 c->decorrelate[2] = flac_decorrelate_rs_c_16p;

123 c->decorrelate[3] = flac_decorrelate_ms_c_16p;

124 break;

125 }

126

127 #if ARCH_ARM

128 ff_flacdsp_init_arm(c, fmt, channels, bps);

129 #elif ARCH_X86

130 ff_flacdsp_init_x86(c, fmt, channels, bps);

131 #endif

132 }

ff_flacdsp_init

av_cold void ff_flacdsp_init(FLACDSPContext *c, enum AVSampleFormat fmt, int channels, int bps)

Definition: flacdsp.c:89

AV_SAMPLE_FMT_S32P

@ AV_SAMPLE_FMT_S32P

signed 32 bits, planar

Definition: samplefmt.h:65

flacdsp.h

samplefmt.h

av_cold

#define av_cold

Definition: attributes.h:90

#define s1

Definition: regdef.h:38

channels

Definition: aptx.h:32

ff_flacdsp_init_x86

void ff_flacdsp_init_x86(FLACDSPContext *c, enum AVSampleFormat fmt, int channels, int bps)

Definition: flacdsp_init.c:55

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

flac_lpc_32_c

static void flac_lpc_32_c(int32_t *decoded, const int coeffs[32], int pred_order, int qlevel, int len)

Definition: flacdsp.c:75

ff_flacdsp_init_arm

av_cold void ff_flacdsp_init_arm(FLACDSPContext *c, enum AVSampleFormat fmt, int channels, int bps)

Definition: flacdsp_init_arm.c:29

bps

unsigned bps

Definition: movenc.c:1647

attributes.h

AV_SAMPLE_FMT_S16P