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
|
/*
* RedSpark demuxer
* Copyright (c) 2013 James Almer
*
* 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 "libavcodec/bytestream.h"
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "avio.h"
#include "internal.h"
#define HEADER_SIZE 4096
#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
typedef struct RedSparkContext {
int samples_count;
} RedSparkContext;
static int redspark_probe(const AVProbeData *p)
{
uint32_t key, data;
uint8_t header[8];
/* Decrypt first 8 bytes of the header */
data = AV_RB32(p->buf);
key = data ^ 0x52656453;
data ^= key;
AV_WB32(header, data);
key = rol(key, 11);
key += rol(key, 3);
data = AV_RB32(p->buf + 4) ^ key;
AV_WB32(header + 4, data);
if (AV_RB64(header) == AV_RB64("RedSpark"))
return AVPROBE_SCORE_MAX;
return 0;
}
static int redspark_read_header(AVFormatContext *s)
{
AVIOContext *pb = s->pb;
RedSparkContext *redspark = s->priv_data;
AVCodecParameters *par;
GetByteContext gbc;
int i, coef_off, ret = 0;
uint32_t key, data;
uint8_t header[HEADER_SIZE];
AVStream *st;
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
par = st->codecpar;
/* Decrypt header */
data = avio_rb32(pb);
key = data ^ 0x52656453;
data ^= key;
AV_WB32(header, data);
key = rol(key, 11);
for (i = 4; i < HEADER_SIZE; i += 4) {
key += rol(key, 3);
data = avio_rb32(pb) ^ key;
AV_WB32(header + i, data);
}
par->codec_id = AV_CODEC_ID_ADPCM_THP;
par->codec_type = AVMEDIA_TYPE_AUDIO;
bytestream2_init(&gbc, header, HEADER_SIZE);
bytestream2_seek(&gbc, 0x3c, SEEK_SET);
par->sample_rate = bytestream2_get_be32u(&gbc);
if (par->sample_rate <= 0 || par->sample_rate > 96000) {
av_log(s, AV_LOG_ERROR, "Invalid sample rate: %d\n", par->sample_rate);
return AVERROR_INVALIDDATA;
}
st->duration = bytestream2_get_be32u(&gbc) * 14;
redspark->samples_count = 0;
bytestream2_skipu(&gbc, 10);
par->ch_layout.nb_channels = bytestream2_get_byteu(&gbc);
if (!par->ch_layout.nb_channels) {
return AVERROR_INVALIDDATA;
}
coef_off = 0x54 + par->ch_layout.nb_channels * 8;
if (bytestream2_get_byteu(&gbc)) // Loop flag
coef_off += 16;
if (coef_off + par->ch_layout.nb_channels * (32 + 14) > HEADER_SIZE) {
return AVERROR_INVALIDDATA;
}
if (ff_alloc_extradata(par, 32 * par->ch_layout.nb_channels)) {
return AVERROR_INVALIDDATA;
}
/* Get the ADPCM table */
bytestream2_seek(&gbc, coef_off, SEEK_SET);
for (i = 0; i < par->ch_layout.nb_channels; i++) {
if (bytestream2_get_bufferu(&gbc, par->extradata + i * 32, 32) != 32) {
return AVERROR_INVALIDDATA;
}
bytestream2_skipu(&gbc, 14);
}
avpriv_set_pts_info(st, 64, 1, par->sample_rate);
return ret;
}
static int redspark_read_packet(AVFormatContext *s, AVPacket *pkt)
{
AVCodecParameters *par = s->streams[0]->codecpar;
RedSparkContext *redspark = s->priv_data;
uint32_t size = 8 * par->ch_layout.nb_channels;
int ret;
if (avio_feof(s->pb) || redspark->samples_count == s->streams[0]->duration)
return AVERROR_EOF;
ret = av_get_packet(s->pb, pkt, size);
if (ret != size) {
return AVERROR(EIO);
}
pkt->duration = 14;
redspark->samples_count += pkt->duration;
pkt->stream_index = 0;
return ret;
}
const AVInputFormat ff_redspark_demuxer = {
.name = "redspark",
.long_name = NULL_IF_CONFIG_SMALL("RedSpark"),
.priv_data_size = sizeof(RedSparkContext),
.read_probe = redspark_probe,
.read_header = redspark_read_header,
.read_packet = redspark_read_packet,
.extensions = "rsd",
};
|