FFmpeg
flacdsp_template.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 <stdint.h>
22 #include "libavutil/avutil.h"
23 
24 #undef FUNC
25 #undef FSUF
26 #undef sample
27 #undef sample_type
28 #undef OUT
29 #undef S
30 
31 #if SAMPLE_SIZE == 32
32 # define sample_type int32_t
33 #else
34 # define sample_type int16_t
35 #endif
36 
37 #if PLANAR
38 # define FSUF AV_JOIN(SAMPLE_SIZE, p)
39 # define sample sample_type *
40 # define OUT(n) n
41 # define S(s, c, i) (s[c][i])
42 #else
43 # define FSUF SAMPLE_SIZE
44 # define sample sample_type
45 # define OUT(n) n[0]
46 # define S(s, c, i) (*s++)
47 #endif
48 
49 #define FUNC(n) AV_JOIN(n ## _, FSUF)
50 
51 static void FUNC(flac_decorrelate_indep_c)(uint8_t **out, int32_t **in,
52  int channels, int len, int shift)
53 {
54  sample *samples = (sample *) OUT(out);
55  int i, j;
56 
57  for (j = 0; j < len; j++)
58  for (i = 0; i < channels; i++)
59  S(samples, i, j) = (int)((unsigned)in[i][j] << shift);
60 }
61 
62 static void FUNC(flac_decorrelate_ls_c)(uint8_t **out, int32_t **in,
63  int channels, int len, int shift)
64 {
65  sample *samples = (sample *) OUT(out);
66  int i;
67 
68  for (i = 0; i < len; i++) {
69  unsigned a = in[0][i];
70  unsigned b = in[1][i];
71  S(samples, 0, i) = a << shift;
72  S(samples, 1, i) = (a - b) << shift;
73  }
74 }
75 
76 static void FUNC(flac_decorrelate_rs_c)(uint8_t **out, int32_t **in,
77  int channels, int len, int shift)
78 {
79  sample *samples = (sample *) OUT(out);
80  int i;
81 
82  for (i = 0; i < len; i++) {
83  unsigned a = in[0][i];
84  unsigned b = in[1][i];
85  S(samples, 0, i) = (a + b) << shift;
86  S(samples, 1, i) = b << shift;
87  }
88 }
89 
90 static void FUNC(flac_decorrelate_ms_c)(uint8_t **out, int32_t **in,
91  int channels, int len, int shift)
92 {
93  sample *samples = (sample *) OUT(out);
94  int i;
95 
96  for (i = 0; i < len; i++) {
97  unsigned a = in[0][i];
98  int b = in[1][i];
99  a -= b >> 1;
100  S(samples, 0, i) = (a + b) << shift;
101  S(samples, 1, i) = a << shift;
102  }
103 }
flac_decorrelate_rs_c
static void FUNC() flac_decorrelate_rs_c(uint8_t **out, int32_t **in, int channels, int len, int shift)
Definition: flacdsp_template.c:76
out
FILE * out
Definition: movenc.c:54
b
#define b
Definition: input.c:40
FUNC
#define FUNC(n)
Definition: flacdsp_template.c:49
S
#define S(s, c, i)
Definition: flacdsp_template.c:46
flac_decorrelate_ms_c
static void FUNC() flac_decorrelate_ms_c(uint8_t **out, int32_t **in, int channels, int len, int shift)
Definition: flacdsp_template.c:90
channels
channels
Definition: aptx.h:33
OUT
#define OUT(n)
Definition: flacdsp_template.c:45
flac_decorrelate_ls_c
static void FUNC() flac_decorrelate_ls_c(uint8_t **out, int32_t **in, int channels, int len, int shift)
Definition: flacdsp_template.c:62
sample
#define sample
Definition: flacdsp_template.c:44
a
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
i
int i
Definition: input.c:406
len
int len
Definition: vorbis_enc_data.h:426
samples
Filter the word “frame” indicates either a video frame or a group of audio samples
Definition: filter_design.txt:8
shift
static int shift(int a, int b)
Definition: sonic.c:83
avutil.h
flac_decorrelate_indep_c
static void FUNC() flac_decorrelate_indep_c(uint8_t **out, int32_t **in, int channels, int len, int shift)
Definition: flacdsp_template.c:51
int32_t
int32_t
Definition: audioconvert.c:56
int
int
Definition: ffmpeg_filter.c:156