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
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
|
/*
* Copyright (c) 2012 Clément Bœsch
*
* 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
*/
/**
* @file
* SubViewer subtitle demuxer
* @see https://en.wikipedia.org/wiki/SubViewer
*/
#include "avformat.h"
#include "internal.h"
#include "subtitles.h"
#include "avio_internal.h"
#include "libavcodec/internal.h"
#include "libavutil/avstring.h"
#include "libavutil/bprint.h"
#include "libavutil/intreadwrite.h"
typedef struct {
FFDemuxSubtitlesQueue q;
} SubViewerContext;
static int subviewer_probe(AVProbeData *p)
{
char c;
const unsigned char *ptr = p->buf;
if (AV_RB24(ptr) == 0xEFBBBF)
ptr += 3; /* skip UTF-8 BOM */
if (sscanf(ptr, "%*u:%*u:%*u.%*u,%*u:%*u:%*u.%*u%c", &c) == 1)
return AVPROBE_SCORE_EXTENSION;
if (!strncmp(ptr, "[INFORMATION]", 13))
return AVPROBE_SCORE_MAX/3;
return 0;
}
static int read_ts(const char *s, int64_t *start, int *duration)
{
int64_t end;
int hh1, mm1, ss1, ms1;
int hh2, mm2, ss2, ms2;
if (sscanf(s, "%u:%u:%u.%u,%u:%u:%u.%u",
&hh1, &mm1, &ss1, &ms1, &hh2, &mm2, &ss2, &ms2) == 8) {
end = (hh2*3600LL + mm2*60LL + ss2) * 100LL + ms2;
*start = (hh1*3600LL + mm1*60LL + ss1) * 100LL + ms1;
*duration = end - *start;
return 0;
}
return -1;
}
static int subviewer_read_header(AVFormatContext *s)
{
SubViewerContext *subviewer = s->priv_data;
AVStream *st = avformat_new_stream(s, NULL);
AVBPrint header;
int res = 0, new_event = 1;
int64_t pts_start = AV_NOPTS_VALUE;
int duration = -1;
AVPacket *sub = NULL;
if (!st)
return AVERROR(ENOMEM);
res = ffio_ensure_seekback(s->pb, 3);
if (res < 0)
return res;
if (avio_rb24(s->pb) != 0xefbbbf)
avio_seek(s->pb, -3, SEEK_CUR);
avpriv_set_pts_info(st, 64, 1, 100);
st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;
st->codecpar->codec_id = AV_CODEC_ID_SUBVIEWER;
av_bprint_init(&header, 0, AV_BPRINT_SIZE_UNLIMITED);
while (!avio_feof(s->pb)) {
char line[2048];
int64_t pos = 0;
int len = ff_get_line(s->pb, line, sizeof(line));
if (!len)
break;
line[strcspn(line, "\r\n")] = 0;
if (line[0] == '[' && strncmp(line, "[br]", 4)) {
/* ignore event style, XXX: add to side_data? */
if (strstr(line, "[COLF]") || strstr(line, "[SIZE]") ||
strstr(line, "[FONT]") || strstr(line, "[STYLE]"))
continue;
if (!st->codecpar->extradata) { // header not finalized yet
av_bprintf(&header, "%s\n", line);
if (!strncmp(line, "[END INFORMATION]", 17) || !strncmp(line, "[SUBTITLE]", 10)) {
/* end of header */
res = ff_bprint_to_codecpar_extradata(st->codecpar, &header);
if (res < 0)
goto end;
} else if (strncmp(line, "[INFORMATION]", 13)) {
/* assume file metadata at this point */
int i, j = 0;
char key[32], value[128];
for (i = 1; i < sizeof(key) - 1 && line[i] && line[i] != ']'; i++)
key[i - 1] = av_tolower(line[i]);
key[i - 1] = 0;
if (line[i] == ']')
i++;
while (line[i] == ' ')
i++;
while (j < sizeof(value) - 1 && line[i] && line[i] != ']')
value[j++] = line[i++];
value[j] = 0;
av_dict_set(&s->metadata, key, value, 0);
}
}
} else if (read_ts(line, &pts_start, &duration) >= 0) {
new_event = 1;
pos = avio_tell(s->pb);
} else if (*line) {
if (!new_event) {
sub = ff_subtitles_queue_insert(&subviewer->q, "\n", 1, 1);
if (!sub) {
res = AVERROR(ENOMEM);
goto end;
}
}
sub = ff_subtitles_queue_insert(&subviewer->q, line, strlen(line), !new_event);
if (!sub) {
res = AVERROR(ENOMEM);
goto end;
}
if (new_event) {
sub->pos = pos;
sub->pts = pts_start;
sub->duration = duration;
}
new_event = 0;
}
}
ff_subtitles_queue_finalize(s, &subviewer->q);
end:
av_bprint_finalize(&header, NULL);
return res;
}
static int subviewer_read_packet(AVFormatContext *s, AVPacket *pkt)
{
SubViewerContext *subviewer = s->priv_data;
return ff_subtitles_queue_read_packet(&subviewer->q, pkt);
}
static int subviewer_read_seek(AVFormatContext *s, int stream_index,
int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
{
SubViewerContext *subviewer = s->priv_data;
return ff_subtitles_queue_seek(&subviewer->q, s, stream_index,
min_ts, ts, max_ts, flags);
}
static int subviewer_read_close(AVFormatContext *s)
{
SubViewerContext *subviewer = s->priv_data;
ff_subtitles_queue_clean(&subviewer->q);
return 0;
}
AVInputFormat ff_subviewer_demuxer = {
.name = "subviewer",
.long_name = NULL_IF_CONFIG_SMALL("SubViewer subtitle format"),
.priv_data_size = sizeof(SubViewerContext),
.read_probe = subviewer_probe,
.read_header = subviewer_read_header,
.read_packet = subviewer_read_packet,
.read_seek2 = subviewer_read_seek,
.read_close = subviewer_read_close,
.extensions = "sub",
};
|
