1 /*
2 * Copyright (c) 2012 Clément Bœsch
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 /**
22 * @file
23 * RealText subtitle demuxer
24 * @see http://service.real.com/help/library/guides/ProductionGuide/prodguide/htmfiles/realtext.htm
25 */
26
27 #include "avformat.h"
28 #include "internal.h"
29 #include "subtitles.h"
30 #include "libavutil/avstring.h"
31 #include "libavutil/bprint.h"
32 #include "libavutil/intreadwrite.h"
33
34 typedef struct {
35 FFDemuxSubtitlesQueue q;
36 } RealTextContext;
37
realtext_probe(const AVProbeData * p)38 static int realtext_probe(const AVProbeData *p)
39 {
40 char buf[7];
41 FFTextReader tr;
42 ff_text_init_buf(&tr, p->buf, p->buf_size);
43 ff_text_read(&tr, buf, sizeof(buf));
44
45 return !av_strncasecmp(buf, "<window", 7) ? AVPROBE_SCORE_EXTENSION : 0;
46 }
47
read_ts(const char * s)48 static int64_t read_ts(const char *s)
49 {
50 int hh, mm, ss, ms;
51
52 if (sscanf(s, "%u:%u:%u.%u", &hh, &mm, &ss, &ms) == 4) return (hh*3600LL + mm*60LL + ss) * 100LL + ms;
53 if (sscanf(s, "%u:%u:%u" , &hh, &mm, &ss ) == 3) return (hh*3600LL + mm*60LL + ss) * 100LL;
54 if (sscanf(s, "%u:%u.%u", &mm, &ss, &ms) == 3) return ( mm*60LL + ss) * 100LL + ms;
55 if (sscanf(s, "%u:%u" , &mm, &ss ) == 2) return ( mm*60LL + ss) * 100LL;
56 if (sscanf(s, "%u.%u", &ss, &ms) == 2) return ( ss) * 100LL + ms;
57 return strtoll(s, NULL, 10) * 100ULL;
58 }
59
realtext_read_header(AVFormatContext * s)60 static int realtext_read_header(AVFormatContext *s)
61 {
62 RealTextContext *rt = s->priv_data;
63 AVStream *st = avformat_new_stream(s, NULL);
64 AVBPrint buf;
65 char c = 0;
66 int res = 0, duration = read_ts("60"); // default duration is 60 seconds
67 FFTextReader tr;
68 ff_text_init_avio(s, &tr, s->pb);
69
70 if (!st)
71 return AVERROR(ENOMEM);
72 avpriv_set_pts_info(st, 64, 1, 100);
73 st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;
74 st->codecpar->codec_id = AV_CODEC_ID_REALTEXT;
75
76 av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED);
77
78 while (!ff_text_eof(&tr)) {
79 AVPacket *sub;
80 const int64_t pos = ff_text_pos(&tr) - (c != 0);
81 int n = ff_smil_extract_next_text_chunk(&tr, &buf, &c);
82
83 if (n == 0)
84 break;
85
86 if (!av_strncasecmp(buf.str, "<window", 7)) {
87 /* save header to extradata */
88 const char *p = ff_smil_get_attr_ptr(buf.str, "duration");
89
90 if (st->codecpar->extradata) {
91 res = AVERROR_INVALIDDATA;
92 goto end;
93 }
94 if (p)
95 duration = read_ts(p);
96 st->codecpar->extradata = av_strdup(buf.str);
97 if (!st->codecpar->extradata) {
98 res = AVERROR(ENOMEM);
99 goto end;
100 }
101 st->codecpar->extradata_size = buf.len + 1;
102 } else {
103 /* if we just read a <time> tag, introduce a new event, otherwise merge
104 * with the previous one */
105 int merge = !av_strncasecmp(buf.str, "<time", 5) ? 0 : 1;
106 sub = ff_subtitles_queue_insert(&rt->q, buf.str, buf.len, merge);
107 if (!sub) {
108 res = AVERROR(ENOMEM);
109 goto end;
110 }
111 if (!merge) {
112 const char *begin = ff_smil_get_attr_ptr(buf.str, "begin");
113 const char *end = ff_smil_get_attr_ptr(buf.str, "end");
114 int64_t endi = end ? read_ts(end) : 0;
115
116 sub->pos = pos;
117 sub->pts = begin ? read_ts(begin) : 0;
118 sub->duration = (end && endi > sub->pts && endi - (uint64_t)sub->pts <= INT64_MAX) ? endi - sub->pts : duration;
119 }
120 }
121 av_bprint_clear(&buf);
122 }
123 ff_subtitles_queue_finalize(s, &rt->q);
124
125 end:
126 av_bprint_finalize(&buf, NULL);
127 if (res < 0)
128 ff_subtitles_queue_clean(&rt->q);
129 return res;
130 }
131
realtext_read_packet(AVFormatContext * s,AVPacket * pkt)132 static int realtext_read_packet(AVFormatContext *s, AVPacket *pkt)
133 {
134 RealTextContext *rt = s->priv_data;
135 return ff_subtitles_queue_read_packet(&rt->q, pkt);
136 }
137
realtext_read_seek(AVFormatContext * s,int stream_index,int64_t min_ts,int64_t ts,int64_t max_ts,int flags)138 static int realtext_read_seek(AVFormatContext *s, int stream_index,
139 int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
140 {
141 RealTextContext *rt = s->priv_data;
142 return ff_subtitles_queue_seek(&rt->q, s, stream_index,
143 min_ts, ts, max_ts, flags);
144 }
145
realtext_read_close(AVFormatContext * s)146 static int realtext_read_close(AVFormatContext *s)
147 {
148 RealTextContext *rt = s->priv_data;
149 ff_subtitles_queue_clean(&rt->q);
150 return 0;
151 }
152
153 AVInputFormat ff_realtext_demuxer = {
154 .name = "realtext",
155 .long_name = NULL_IF_CONFIG_SMALL("RealText subtitle format"),
156 .priv_data_size = sizeof(RealTextContext),
157 .read_probe = realtext_probe,
158 .read_header = realtext_read_header,
159 .read_packet = realtext_read_packet,
160 .read_seek2 = realtext_read_seek,
161 .read_close = realtext_read_close,
162 .extensions = "rt",
163 };
164