FFmpeg
Main Page
Related Pages
Modules
Namespaces
Data Structures
Files
Examples
File List
Globals
All
Data Structures
Namespaces
Files
Functions
Variables
Typedefs
Enumerations
Enumerator
Macros
Groups
Pages
libavformat
lvfdec.c
Go to the documentation of this file.
1
/*
2
* LVF demuxer
3
* Copyright (c) 2012 Paul B Mahol
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 "
libavutil/intreadwrite.h
"
23
#include "
avformat.h
"
24
#include "
riff.h
"
25
26
static
int
lvf_probe
(
AVProbeData
*p)
27
{
28
if
(
AV_RL32
(p->
buf
) !=
MKTAG
(
'L'
,
'V'
,
'F'
,
'F'
))
29
return
0;
30
31
if
(!
AV_RL32
(p->
buf
+ 16) ||
AV_RL32
(p->
buf
+ 16) > 256)
32
return
AVPROBE_SCORE_MAX
/ 8;
33
34
return
AVPROBE_SCORE_EXTENSION
;
35
}
36
37
static
int
lvf_read_header
(
AVFormatContext
*
s
)
38
{
39
AVStream
*st;
40
int64_t next_offset;
41
unsigned
size
,
nb_streams
,
id
;
42
43
avio_skip
(s->
pb
, 16);
44
nb_streams =
avio_rl32
(s->
pb
);
45
if
(!nb_streams)
46
return
AVERROR_INVALIDDATA
;
47
if
(nb_streams > 2) {
48
avpriv_request_sample
(s,
"%d streams"
, nb_streams);
49
return
AVERROR_PATCHWELCOME
;
50
}
51
52
avio_skip
(s->
pb
, 1012);
53
54
while
(!
avio_feof
(s->
pb
)) {
55
id
=
avio_rl32
(s->
pb
);
56
size =
avio_rl32
(s->
pb
);
57
next_offset =
avio_tell
(s->
pb
) +
size
;
58
59
switch
(
id
) {
60
case
MKTAG
(
'0'
,
'0'
,
'f'
,
'm'
):
61
st =
avformat_new_stream
(s, 0);
62
if
(!st)
63
return
AVERROR
(ENOMEM);
64
65
st->
codec
->
codec_type
=
AVMEDIA_TYPE_VIDEO
;
66
avio_skip
(s->
pb
, 4);
67
st->
codec
->
width
=
avio_rl32
(s->
pb
);
68
st->
codec
->
height
=
avio_rl32
(s->
pb
);
69
avio_skip
(s->
pb
, 4);
70
st->
codec
->
codec_tag
=
avio_rl32
(s->
pb
);
71
st->
codec
->
codec_id
=
ff_codec_get_id
(
ff_codec_bmp_tags
,
72
st->
codec
->
codec_tag
);
73
avpriv_set_pts_info
(st, 32, 1, 1000);
74
break
;
75
case
MKTAG
(
'0'
,
'1'
,
'f'
,
'm'
):
76
st =
avformat_new_stream
(s, 0);
77
if
(!st)
78
return
AVERROR
(ENOMEM);
79
80
st->
codec
->
codec_type
=
AVMEDIA_TYPE_AUDIO
;
81
st->
codec
->
codec_tag
=
avio_rl16
(s->
pb
);
82
st->
codec
->
channels
=
avio_rl16
(s->
pb
);
83
st->
codec
->
sample_rate
=
avio_rl16
(s->
pb
);
84
avio_skip
(s->
pb
, 8);
85
st->
codec
->
bits_per_coded_sample
=
avio_r8
(s->
pb
);
86
st->
codec
->
codec_id
=
ff_codec_get_id
(
ff_codec_wav_tags
,
87
st->
codec
->
codec_tag
);
88
avpriv_set_pts_info
(st, 32, 1, 1000);
89
break
;
90
case
0:
91
avio_seek
(s->
pb
, 2048 + 8, SEEK_SET);
92
return
0;
93
default
:
94
avpriv_request_sample
(s,
"id %d"
,
id
);
95
return
AVERROR_PATCHWELCOME
;
96
}
97
98
avio_seek
(s->
pb
, next_offset, SEEK_SET);
99
}
100
101
return
AVERROR_EOF
;
102
}
103
104
static
int
lvf_read_packet
(
AVFormatContext
*
s
,
AVPacket
*
pkt
)
105
{
106
unsigned
size
,
flags
, timestamp,
id
;
107
int64_t pos;
108
int
ret
, is_video = 0;
109
110
pos =
avio_tell
(s->
pb
);
111
while
(!
avio_feof
(s->
pb
)) {
112
id
=
avio_rl32
(s->
pb
);
113
size =
avio_rl32
(s->
pb
);
114
115
if
(size == 0xFFFFFFFFu)
116
return
AVERROR_EOF
;
117
118
switch
(
id
) {
119
case
MKTAG
(
'0'
,
'0'
,
'd'
,
'c'
):
120
is_video = 1;
121
case
MKTAG
(
'0'
,
'1'
,
'w'
,
'b'
):
122
if
(size < 8)
123
return
AVERROR_INVALIDDATA
;
124
timestamp =
avio_rl32
(s->
pb
);
125
flags =
avio_rl32
(s->
pb
);
126
ret =
av_get_packet
(s->
pb
, pkt, size - 8);
127
if
(flags & (1 << 12))
128
pkt->
flags
|=
AV_PKT_FLAG_KEY
;
129
pkt->
stream_index
= is_video ? 0 : 1;
130
pkt->
pts
= timestamp;
131
pkt->
pos
= pos;
132
return
ret
;
133
default
:
134
ret =
avio_skip
(s->
pb
, size);
135
}
136
137
if
(ret < 0)
138
return
ret
;
139
}
140
141
return
AVERROR_EOF
;
142
}
143
144
AVInputFormat
ff_lvf_demuxer
= {
145
.
name
=
"lvf"
,
146
.long_name =
NULL_IF_CONFIG_SMALL
(
"LVF"
),
147
.read_probe =
lvf_probe
,
148
.read_header =
lvf_read_header
,
149
.read_packet =
lvf_read_packet
,
150
.extensions =
"lvf"
,
151
.flags =
AVFMT_GENERIC_INDEX
,
152
};
Generated on Fri Dec 5 2014 04:42:11 for FFmpeg by
1.8.2