FFmpeg
flacdsp.c
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1 /*
2  * Copyright (c) 2012 Mans Rullgard <mans@mansr.com>
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  */
20 
21 #include "libavutil/attributes.h"
22 #include "libavutil/samplefmt.h"
23 #include "flacdsp.h"
24 #include "config.h"
25 
26 #define SAMPLE_SIZE 16
27 #define PLANAR 0
28 #include "flacdsp_template.c"
29 #include "flacdsp_lpc_template.c"
30 
31 #undef PLANAR
32 #define PLANAR 1
33 #include "flacdsp_template.c"
34 
35 #undef SAMPLE_SIZE
36 #undef PLANAR
37 #define SAMPLE_SIZE 32
38 #define PLANAR 0
39 #include "flacdsp_template.c"
40 #include "flacdsp_lpc_template.c"
41 
42 #undef PLANAR
43 #define PLANAR 1
44 #include "flacdsp_template.c"
45 
46 static void flac_lpc_16_c(int32_t *decoded, const int coeffs[32],
47  int pred_order, int qlevel, int len)
48 {
49  int i, j;
50 
51  for (i = pred_order; i < len - 1; i += 2, decoded += 2) {
52  SUINT c = coeffs[0];
53  SUINT d = decoded[0];
54  int s0 = 0, s1 = 0;
55  for (j = 1; j < pred_order; j++) {
56  s0 += c*d;
57  d = decoded[j];
58  s1 += c*d;
59  c = coeffs[j];
60  }
61  s0 += c*d;
62  d = decoded[j] += (SUINT)(s0 >> qlevel);
63  s1 += c*d;
64  decoded[j + 1] += (SUINT)(s1 >> qlevel);
65  }
66  if (i < len) {
67  int sum = 0;
68  for (j = 0; j < pred_order; j++)
69  sum += coeffs[j] * (SUINT)decoded[j];
70  decoded[j] = decoded[j] + (unsigned)(sum >> qlevel);
71  }
72 }
73 
74 static void flac_lpc_32_c(int32_t *decoded, const int coeffs[32],
75  int pred_order, int qlevel, int len)
76 {
77  int i, j;
78 
79  for (i = pred_order; i < len; i++, decoded++) {
80  int64_t sum = 0;
81  for (j = 0; j < pred_order; j++)
82  sum += (int64_t)coeffs[j] * decoded[j];
83  decoded[j] += sum >> qlevel;
84  }
85 
86 }
87 
89  int bps)
90 {
91  c->lpc16 = flac_lpc_16_c;
92  c->lpc32 = flac_lpc_32_c;
93  c->lpc16_encode = flac_lpc_encode_c_16;
94  c->lpc32_encode = flac_lpc_encode_c_32;
95 
96  switch (fmt) {
97  case AV_SAMPLE_FMT_S32:
98  c->decorrelate[0] = flac_decorrelate_indep_c_32;
99  c->decorrelate[1] = flac_decorrelate_ls_c_32;
100  c->decorrelate[2] = flac_decorrelate_rs_c_32;
101  c->decorrelate[3] = flac_decorrelate_ms_c_32;
102  break;
103 
104  case AV_SAMPLE_FMT_S32P:
105  c->decorrelate[0] = flac_decorrelate_indep_c_32p;
106  c->decorrelate[1] = flac_decorrelate_ls_c_32p;
107  c->decorrelate[2] = flac_decorrelate_rs_c_32p;
108  c->decorrelate[3] = flac_decorrelate_ms_c_32p;
109  break;
110 
111  case AV_SAMPLE_FMT_S16:
112  c->decorrelate[0] = flac_decorrelate_indep_c_16;
113  c->decorrelate[1] = flac_decorrelate_ls_c_16;
114  c->decorrelate[2] = flac_decorrelate_rs_c_16;
115  c->decorrelate[3] = flac_decorrelate_ms_c_16;
116  break;
117 
118  case AV_SAMPLE_FMT_S16P:
119  c->decorrelate[0] = flac_decorrelate_indep_c_16p;
120  c->decorrelate[1] = flac_decorrelate_ls_c_16p;
121  c->decorrelate[2] = flac_decorrelate_rs_c_16p;
122  c->decorrelate[3] = flac_decorrelate_ms_c_16p;
123  break;
124  }
125 
126  if (ARCH_ARM)
127  ff_flacdsp_init_arm(c, fmt, channels, bps);
128  if (ARCH_X86)
129  ff_flacdsp_init_x86(c, fmt, channels, bps);
130 }
const char * fmt
Definition: avisynth_c.h:861
av_cold void ff_flacdsp_init(FLACDSPContext *c, enum AVSampleFormat fmt, int channels, int bps)
Definition: flacdsp.c:88
channels
Definition: aptx.c:30
void(* lpc32)(int32_t *samples, const int coeffs[32], int order, int qlevel, int len)
Definition: flacdsp.h:31
#define SUINT
Macro definitions for various function/variable attributes.
#define av_cold
Definition: attributes.h:82
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
signed 32 bits
Definition: samplefmt.h:62
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define s0
Definition: regdef.h:37
void(* lpc16)(int32_t *samples, const int coeffs[32], int order, int qlevel, int len)
Definition: flacdsp.h:29
signed 32 bits, planar
Definition: samplefmt.h:68
int32_t
void ff_flacdsp_init_x86(FLACDSPContext *c, enum AVSampleFormat fmt, int channels, int bps)
Definition: flacdsp_init.c:53
static void flac_lpc_16_c(int32_t *decoded, const int coeffs[32], int pred_order, int qlevel, int len)
Definition: flacdsp.c:46
static void flac_lpc_32_c(int32_t *decoded, const int coeffs[32], int pred_order, int qlevel, int len)
Definition: flacdsp.c:74
void(* lpc16_encode)(int32_t *res, const int32_t *smp, int len, int order, const int32_t coefs[32], int shift)
Definition: flacdsp.h:33
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
#define s1
Definition: regdef.h:38
av_cold void ff_flacdsp_init_arm(FLACDSPContext *c, enum AVSampleFormat fmt, int channels, int bps)
signed 16 bits
Definition: samplefmt.h:61
void(* lpc32_encode)(int32_t *res, const int32_t *smp, int len, int order, const int32_t coefs[32], int shift)
Definition: flacdsp.h:35
unsigned bps
Definition: movenc.c:1532
int len
signed 16 bits, planar
Definition: samplefmt.h:67
void(* decorrelate[4])(uint8_t **out, int32_t **in, int channels, int len, int shift)
Definition: flacdsp.h:27