blob: 33b87469eaad2cf90030f94cf3fd2db07340b6ef (
plain)
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
|
/*
Copyright (C) 2014 Matthias P. Braendli (http://www.opendigitalradio.org)
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
dabplussnoop.cpp
Parse DAB+ frames from a ETI file
Authors:
Matthias P. Braendli <matthias@mpb.li>
*/
/* From the spec:
subchannel_index = MSC sub-channel size (kbps) / 8
audio_super_frame_size (bytes) = subchannel_index * 110
// Derived from
// au_start[n] = au_start[n - 1] + au_size[n - 1] + 2;
// 2 bytes for CRC
au_size[n] = au_start[n+1] - au_start[n] - 2;
he_aac_super_frame(subchannel_index)
{
he_aac_super_frame_header()
{
header_firecode 16
rfa 1
dac_rate 1
sbr_flag 1
aac_channel_mode 1
ps_flag 1
mpeg_surround_config 3
// end of audio parameters
if ((dac_rate == 0) && (sbr_flag == 1)) num_aus = 2;
// AAC core sampling rate 16 kHz
if ((dac_rate == 1) && (sbr_flag == 1)) num_aus = 3;
// AAC core sampling rate 24 kHz
if ((dac_rate == 0) && (sbr_flag == 0)) num_aus = 4;
// AAC core sampling rate 32 kHz
if ((dac_rate == 1) && (sbr_flag == 0)) num_aus = 6;
// AAC core sampling rate 48 kHz
for (n = 1; n < num_aus; n++) {
au_start[n]; 12
}
if !((dac_rate == 1) && (sbr_flag == 1))
alignment 4
}
for (n = 0; n < num_aus; n++) {
au[n] 8 * au_size[n]
au_crc[n] 16
}
}
*/
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <string>
#include <sstream>
#include <vector>
#include "faad_decoder.h"
#ifndef __DABPLUSSNOOP_H_
#define __DABPLUSSNOOP_H_
class DabPlusSnoop
{
public:
DabPlusSnoop() :
m_index(0),
m_subchannel_index(0),
m_data(0),
m_raw_data_stream_fd(NULL) {}
void set_subchannel_index(unsigned subchannel_index)
{
m_subchannel_index = subchannel_index;
}
void set_index(int index)
{
m_index = index;
}
void push(uint8_t* streamdata, size_t streamsize);
void close(void);
private:
/* Data needed for FAAD */
FaadDecoder m_faad_decoder;
int m_index;
bool m_ps_flag;
bool m_aac_channel_mode;
bool m_dac_rate;
bool m_sbr_flag;
int m_mpeg_surround_config;
/* Functions */
bool seek_valid_firecode(void);
bool decode(void);
bool extract_au(std::vector<int> au_start);
bool analyse_au(std::vector<std::vector<uint8_t> >& aus);
unsigned m_subchannel_index;
std::vector<uint8_t> m_data;
FILE* m_raw_data_stream_fd;
};
#endif
|
