FFmpeg
mlpdsp.c
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1 /*
2  * Copyright (c) 2007-2008 Ian Caulfield
3  * 2009 Ramiro Polla
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "config.h"
23 #include "libavutil/attributes.h"
24 #include "mlpdsp.h"
25 #include "mlp.h"
26 
28  int firorder, int iirorder,
29  unsigned int filter_shift, int32_t mask,
30  int blocksize, int32_t *sample_buffer)
31 {
32  int32_t *firbuf = state;
34  const int32_t *fircoeff = coeff;
35  const int32_t *iircoeff = coeff + MAX_FIR_ORDER;
36  int i;
37 
38  for (i = 0; i < blocksize; i++) {
39  int32_t residual = *sample_buffer;
40  unsigned int order;
41  int64_t accum = 0;
43 
44  for (order = 0; order < firorder; order++)
45  accum += (int64_t) firbuf[order] * fircoeff[order];
46  for (order = 0; order < iirorder; order++)
47  accum += (int64_t) iirbuf[order] * iircoeff[order];
48 
49  accum = accum >> filter_shift;
50  result = (accum + residual) & mask;
51 
52  *--firbuf = result;
53  *--iirbuf = result - accum;
54 
55  *sample_buffer = result;
56  sample_buffer += MAX_CHANNELS;
57  }
58 }
59 
61  const int32_t *coeffs,
62  const uint8_t *bypassed_lsbs,
63  const int8_t *noise_buffer,
64  int index,
65  unsigned int dest_ch,
66  uint16_t blockpos,
67  unsigned int maxchan,
68  int matrix_noise_shift,
69  int access_unit_size_pow2,
70  int32_t mask)
71 {
72  unsigned int src_ch, i;
73  int index2 = 2 * index + 1;
74  for (i = 0; i < blockpos; i++) {
75  int64_t accum = 0;
76 
77  for (src_ch = 0; src_ch <= maxchan; src_ch++)
78  accum += (int64_t) samples[src_ch] * coeffs[src_ch];
79 
80  if (matrix_noise_shift) {
81  index &= access_unit_size_pow2 - 1;
82  accum += noise_buffer[index] * (1 << (matrix_noise_shift + 7));
83  index += index2;
84  }
85 
86  samples[dest_ch] = ((accum >> 14) & mask) + *bypassed_lsbs;
87  bypassed_lsbs += MAX_CHANNELS;
89  }
90 }
91 
92 static int32_t (*mlp_select_pack_output(uint8_t *ch_assign,
93  int8_t *output_shift,
94  uint8_t max_matrix_channel,
95  int is32))(int32_t, uint16_t, int32_t (*)[], void *, uint8_t*, int8_t *, uint8_t, int)
96 {
97  return ff_mlp_pack_output;
98 }
99 
100 int32_t ff_mlp_pack_output(int32_t lossless_check_data,
101  uint16_t blockpos,
102  int32_t (*sample_buffer)[MAX_CHANNELS],
103  void *data,
104  uint8_t *ch_assign,
105  int8_t *output_shift,
106  uint8_t max_matrix_channel,
107  int is32)
108 {
109  unsigned int i, out_ch = 0;
110  int32_t *data_32 = data;
111  int16_t *data_16 = data;
112 
113  for (i = 0; i < blockpos; i++) {
114  for (out_ch = 0; out_ch <= max_matrix_channel; out_ch++) {
115  int mat_ch = ch_assign[out_ch];
116  int32_t sample = sample_buffer[i][mat_ch] *
117  (1U << output_shift[mat_ch]);
118  lossless_check_data ^= (sample & 0xffffff) << mat_ch;
119  if (is32)
120  *data_32++ = sample * 256U;
121  else
122  *data_16++ = sample >> 8;
123  }
124  }
125  return lossless_check_data;
126 }
127 
129 {
130  c->mlp_filter_channel = mlp_filter_channel;
131  c->mlp_rematrix_channel = ff_mlp_rematrix_channel;
132  c->mlp_select_pack_output = mlp_select_pack_output;
133  c->mlp_pack_output = ff_mlp_pack_output;
134  if (ARCH_ARM)
136  if (ARCH_X86)
138 }
index
fg index
Definition: ffmpeg_filter.c:167
data
const char data[16]
Definition: mxf.c:143
ff_mlpdsp_init
av_cold void ff_mlpdsp_init(MLPDSPContext *c)
Definition: mlpdsp.c:128
U
#define U(x)
Definition: vp56_arith.h:37
mlp_filter_channel
static void mlp_filter_channel(int32_t *state, const int32_t *coeff, int firorder, int iirorder, unsigned int filter_shift, int32_t mask, int blocksize, int32_t *sample_buffer)
Definition: mlpdsp.c:27
mlp_select_pack_output
static int32_t(*)(int32_t, uint16_t, int32_t(*)[], void *, uint8_t *, int8_t *, uint8_t, int) mlp_select_pack_output(uint8_t *ch_assign, int8_t *output_shift, uint8_t max_matrix_channel, int is32)
Definition: mlpdsp.c:92
av_cold
#define av_cold
Definition: attributes.h:90
ff_mlp_pack_output
int32_t ff_mlp_pack_output(int32_t lossless_check_data, uint16_t blockpos, int32_t(*sample_buffer)[MAX_CHANNELS], void *data, uint8_t *ch_assign, int8_t *output_shift, uint8_t max_matrix_channel, int is32)
Definition: mlpdsp.c:100
mask
static const uint16_t mask[17]
Definition: lzw.c:38
result
and forward the result(frame or status change) to the corresponding input. If nothing is possible
c
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
ff_mlp_rematrix_channel
void ff_mlp_rematrix_channel(int32_t *samples, const int32_t *coeffs, const uint8_t *bypassed_lsbs, const int8_t *noise_buffer, int index, unsigned int dest_ch, uint16_t blockpos, unsigned int maxchan, int matrix_noise_shift, int access_unit_size_pow2, int32_t mask)
Definition: mlpdsp.c:60
state
static struct @320 state
sample
#define sample
Definition: flacdsp_template.c:44
mlpdsp.h
attributes.h
MAX_CHANNELS
#define MAX_CHANNELS
Definition: aac.h:48
MAX_FIR_ORDER
#define MAX_FIR_ORDER
The maximum number of taps in IIR and FIR filters.
Definition: mlp.h:65
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
MAX_BLOCKSIZE
#define MAX_BLOCKSIZE
Definition: diracdec.c:55
ff_mlpdsp_init_x86
void ff_mlpdsp_init_x86(MLPDSPContext *c)
Definition: mlpdsp_init.c:196
samples
Filter the word “frame” indicates either a video frame or a group of audio samples
Definition: filter_design.txt:8
ff_mlpdsp_init_arm
av_cold void ff_mlpdsp_init_arm(MLPDSPContext *c)
Definition: mlpdsp_init_arm.c:136
mlp.h
int32_t
int32_t
Definition: audioconvert.c:56
coeff
static const double coeff[2][5]
Definition: vf_owdenoise.c:78
MLPDSPContext
Definition: mlpdsp.h:49
int
int
Definition: ffmpeg_filter.c:153