1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
|
/*
* TAK common code
* Copyright (c) 2012 Paul B Mahol
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "tak.h"
#include "libavutil/crc.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/bswap.h"
static const int64_t tak_channel_layouts[] = {
0,
AV_CH_FRONT_LEFT,
AV_CH_FRONT_RIGHT,
AV_CH_FRONT_CENTER,
AV_CH_LOW_FREQUENCY,
AV_CH_BACK_LEFT,
AV_CH_BACK_RIGHT,
AV_CH_FRONT_LEFT_OF_CENTER,
AV_CH_FRONT_RIGHT_OF_CENTER,
AV_CH_BACK_CENTER,
AV_CH_SIDE_LEFT,
AV_CH_SIDE_RIGHT,
AV_CH_TOP_CENTER,
AV_CH_TOP_FRONT_LEFT,
AV_CH_TOP_FRONT_CENTER,
AV_CH_TOP_FRONT_RIGHT,
AV_CH_TOP_BACK_LEFT,
AV_CH_TOP_BACK_CENTER,
AV_CH_TOP_BACK_RIGHT,
};
static const uint16_t frame_duration_type_quants[] = {
3, 4, 6, 8, 4096, 8192, 16384, 512, 1024, 2048,
};
static int tak_get_nb_samples(int sample_rate, enum TAKFrameSizeType type)
{
int nb_samples, max_nb_samples;
if (type <= TAK_FST_250ms) {
nb_samples = sample_rate * frame_duration_type_quants[type] >>
TAK_FRAME_DURATION_QUANT_SHIFT;
max_nb_samples = 16384;
} else if (type < FF_ARRAY_ELEMS(frame_duration_type_quants)) {
nb_samples = frame_duration_type_quants[type];
max_nb_samples = sample_rate * frame_duration_type_quants[TAK_FST_250ms] >>
TAK_FRAME_DURATION_QUANT_SHIFT;
} else {
return AVERROR_INVALIDDATA;
}
if (nb_samples <= 0 || nb_samples > max_nb_samples)
return AVERROR_INVALIDDATA;
return nb_samples;
}
static int crc_init = 0;
#if CONFIG_SMALL
#define CRC_TABLE_SIZE 257
#else
#define CRC_TABLE_SIZE 1024
#endif
static AVCRC crc_24[CRC_TABLE_SIZE];
av_cold void ff_tak_init_crc(void)
{
if (!crc_init) {
av_crc_init(crc_24, 0, 24, 0x864CFBU, sizeof(crc_24));
crc_init = 1;
}
}
int ff_tak_check_crc(const uint8_t *buf, unsigned int buf_size)
{
uint32_t crc, CRC;
if (buf_size < 4)
return AVERROR_INVALIDDATA;
buf_size -= 3;
CRC = av_bswap32(AV_RL24(buf + buf_size)) >> 8;
crc = av_crc(crc_24, 0xCE04B7U, buf, buf_size);
if (CRC != crc)
return AVERROR_INVALIDDATA;
return 0;
}
void avpriv_tak_parse_streaminfo(GetBitContext *gb, TAKStreamInfo *s)
{
uint64_t channel_mask = 0;
int frame_type, i;
s->codec = get_bits(gb, TAK_ENCODER_CODEC_BITS);
skip_bits(gb, TAK_ENCODER_PROFILE_BITS);
frame_type = get_bits(gb, TAK_SIZE_FRAME_DURATION_BITS);
s->samples = get_bits_longlong(gb, TAK_SIZE_SAMPLES_NUM_BITS);
s->data_type = get_bits(gb, TAK_FORMAT_DATA_TYPE_BITS);
s->sample_rate = get_bits(gb, TAK_FORMAT_SAMPLE_RATE_BITS) + TAK_SAMPLE_RATE_MIN;
s->bps = get_bits(gb, TAK_FORMAT_BPS_BITS) + TAK_BPS_MIN;
s->channels = get_bits(gb, TAK_FORMAT_CHANNEL_BITS) + TAK_CHANNELS_MIN;
if (get_bits1(gb)) {
skip_bits(gb, TAK_FORMAT_VALID_BITS);
if (get_bits1(gb)) {
for (i = 0; i < s->channels; i++) {
int value = get_bits(gb, TAK_FORMAT_CH_LAYOUT_BITS);
if (value < FF_ARRAY_ELEMS(tak_channel_layouts))
channel_mask |= tak_channel_layouts[value];
}
}
}
s->ch_layout = channel_mask;
s->frame_samples = tak_get_nb_samples(s->sample_rate, frame_type);
}
#define FRAME_IS_LAST 1
#define FRAME_HAVE_INFO 2
#define FRAME_HAVE_METADATA 4
int ff_tak_decode_frame_header(AVCodecContext *avctx, GetBitContext *gb,
TAKStreamInfo *ti, int log_level_offset)
{
int flags;
if (get_bits(gb, TAK_FRAME_HEADER_SYNC_ID_BITS) != TAK_FRAME_HEADER_SYNC_ID) {
av_log(avctx, AV_LOG_ERROR + log_level_offset, "missing sync id\n");
return AVERROR_INVALIDDATA;
}
flags = get_bits(gb, TAK_FRAME_HEADER_FLAGS_BITS);
ti->frame_num = get_bits(gb, TAK_FRAME_HEADER_NO_BITS);
if (flags & FRAME_IS_LAST) {
ti->last_frame_samples = get_bits(gb, TAK_FRAME_HEADER_SAMPLE_COUNT_BITS) + 1;
skip_bits(gb, 2);
} else {
ti->last_frame_samples = 0;
}
if (flags & FRAME_HAVE_INFO) {
avpriv_tak_parse_streaminfo(gb, ti);
if (get_bits(gb, 6))
skip_bits(gb, 25);
align_get_bits(gb);
}
if (flags & FRAME_HAVE_METADATA)
return AVERROR_INVALIDDATA;
skip_bits(gb, 24);
return 0;
}
|
