FFmpeg  2.1.1
realtextdec.c
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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 {
37 
39 {
40  const unsigned char *ptr = p->buf;
41 
42  if (AV_RB24(ptr) == 0xEFBBBF)
43  ptr += 3; /* skip UTF-8 BOM */
44  return !av_strncasecmp(ptr, "<window", 7) ? AVPROBE_SCORE_EXTENSION : 0;
45 }
46 
47 static int read_ts(const char *s)
48 {
49  int hh, mm, ss, ms;
50 
51  if (sscanf(s, "%u:%u:%u.%u", &hh, &mm, &ss, &ms) == 4) return (hh*3600 + mm*60 + ss) * 100 + ms;
52  if (sscanf(s, "%u:%u:%u" , &hh, &mm, &ss ) == 3) return (hh*3600 + mm*60 + ss) * 100;
53  if (sscanf(s, "%u:%u.%u", &mm, &ss, &ms) == 3) return ( mm*60 + ss) * 100 + ms;
54  if (sscanf(s, "%u:%u" , &mm, &ss ) == 2) return ( mm*60 + ss) * 100;
55  if (sscanf(s, "%u.%u", &ss, &ms) == 2) return ( ss) * 100 + ms;
56  return strtol(s, NULL, 10) * 100;
57 }
58 
60 {
61  RealTextContext *rt = s->priv_data;
62  AVStream *st = avformat_new_stream(s, NULL);
63  AVBPrint buf;
64  char c = 0;
65  int res = 0, duration = read_ts("60"); // default duration is 60 seconds
66 
67  if (!st)
68  return AVERROR(ENOMEM);
69  avpriv_set_pts_info(st, 64, 1, 100);
72 
74 
75  while (!url_feof(s->pb)) {
76  AVPacket *sub;
77  const int64_t pos = avio_tell(s->pb) - (c != 0);
78  int n = ff_smil_extract_next_chunk(s->pb, &buf, &c);
79 
80  if (n == 0)
81  break;
82 
83  if (!av_strncasecmp(buf.str, "<window", 7)) {
84  /* save header to extradata */
85  const char *p = ff_smil_get_attr_ptr(buf.str, "duration");
86 
87  if (p)
88  duration = read_ts(p);
89  st->codec->extradata = av_strdup(buf.str);
90  if (!st->codec->extradata) {
91  res = AVERROR(ENOMEM);
92  goto end;
93  }
94  st->codec->extradata_size = buf.len + 1;
95  } else {
96  /* if we just read a <time> tag, introduce a new event, otherwise merge
97  * with the previous one */
98  int merge = !av_strncasecmp(buf.str, "<time", 5) ? 0 : 1;
99  sub = ff_subtitles_queue_insert(&rt->q, buf.str, buf.len, merge);
100  if (!sub) {
101  res = AVERROR(ENOMEM);
102  goto end;
103  }
104  if (!merge) {
105  const char *begin = ff_smil_get_attr_ptr(buf.str, "begin");
106  const char *end = ff_smil_get_attr_ptr(buf.str, "end");
107 
108  sub->pos = pos;
109  sub->pts = begin ? read_ts(begin) : 0;
110  sub->duration = end ? (read_ts(end) - sub->pts) : duration;
111  }
112  }
113  av_bprint_clear(&buf);
114  }
116 
117 end:
118  av_bprint_finalize(&buf, NULL);
119  return res;
120 }
121 
123 {
124  RealTextContext *rt = s->priv_data;
125  return ff_subtitles_queue_read_packet(&rt->q, pkt);
126 }
127 
128 static int realtext_read_seek(AVFormatContext *s, int stream_index,
129  int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
130 {
131  RealTextContext *rt = s->priv_data;
132  return ff_subtitles_queue_seek(&rt->q, s, stream_index,
133  min_ts, ts, max_ts, flags);
134 }
135 
137 {
138  RealTextContext *rt = s->priv_data;
140  return 0;
141 }
142 
144  .name = "realtext",
145  .long_name = NULL_IF_CONFIG_SMALL("RealText subtitle format"),
146  .priv_data_size = sizeof(RealTextContext),
150  .read_seek2 = realtext_read_seek,
152  .extensions = "rt",
153 };
static int realtext_read_close(AVFormatContext *s)
Definition: realtextdec.c:136
const char * s
Definition: avisynth_c.h:668
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:478
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1092
char * av_strdup(const char *s) av_malloc_attrib
Duplicate the string s.
Definition: mem.c:256
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:3922
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:686
static int realtext_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: realtextdec.c:122
static int read_ts(const char *s)
Definition: realtextdec.c:47
void ff_subtitles_queue_clean(FFDemuxSubtitlesQueue *q)
Remove and destroy all the subtitles packets.
Definition: subtitles.c:185
int av_strncasecmp(const char *a, const char *b, size_t n)
Locale-independent case-insensitive compare.
Definition: avstring.c:222
AVPacket * ff_subtitles_queue_insert(FFDemuxSubtitlesQueue *q, const uint8_t *event, int len, int merge)
Insert a new subtitle event.
Definition: subtitles.c:26
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1254
Format I/O context.
Definition: avformat.h:968
static uint8_t * res
Definition: ffhash.c:43
const char * ff_smil_get_attr_ptr(const char *s, const char *attr)
SMIL helper to point on the value of an attribute in the given tag.
Definition: subtitles.c:218
int ff_subtitles_queue_read_packet(FFDemuxSubtitlesQueue *q, AVPacket *pkt)
Generic read_packet() callback for subtitles demuxers using this queue system.
Definition: subtitles.c:96
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:67
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:336
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:248
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
static int64_t duration
Definition: ffplay.c:306
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3348
int duration
Duration of this packet in AVStream-&gt;time_base units, 0 if unknown.
Definition: avcodec.h:1085
FFDemuxSubtitlesQueue q
Definition: realtextdec.c:35
void * priv_data
Format private data.
Definition: avformat.h:988
#define AV_BPRINT_SIZE_UNLIMITED
Convenience macros for special values for av_bprint_init() size_max parameter.
Definition: bprint.h:91
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:151
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
Definition: bprint.c:235
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
Init a print buffer.
Definition: bprint.c:69
static int realtext_read_seek(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
Definition: realtextdec.c:128
Buffer to print data progressively.
Definition: bprint.h:77
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:54
static int realtext_read_header(AVFormatContext *s)
Definition: realtextdec.c:59
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:341
int ff_smil_extract_next_chunk(AVIOContext *pb, AVBPrint *buf, char *c)
SMIL helper to load next chunk (&quot;&lt;...&gt;&quot; or untagged content) in buf.
Definition: subtitles.c:195
void ff_subtitles_queue_finalize(FFDemuxSubtitlesQueue *q)
Set missing durations and sort subtitles by PTS, and then byte position.
Definition: subtitles.c:84
int n
Definition: avisynth_c.h:588
static int realtext_probe(AVProbeData *p)
Definition: realtextdec.c:38
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:592
Stream structure.
Definition: avformat.h:667
int ff_subtitles_queue_seek(FFDemuxSubtitlesQueue *q, AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
Update current_sub_idx to emulate a seek.
Definition: subtitles.c:133
enum AVMediaType codec_type
Definition: avcodec.h:1154
enum AVCodecID codec_id
Definition: avcodec.h:1157
AVInputFormat ff_realtext_demuxer
Definition: realtextdec.c:143
AVIOContext * pb
I/O context.
Definition: avformat.h:1001
void * buf
Definition: avisynth_c.h:594
int extradata_size
Definition: avcodec.h:1255
static int read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: libcdio.c:114
void av_bprint_clear(AVBPrint *buf)
Reset the string to &quot;&quot; but keep internal allocated data.
Definition: bprint.c:227
#define AV_RB24(x)
Definition: intreadwrite.h:436
This structure contains the data a format has to probe a file.
Definition: avformat.h:334
static void merge(GetBitContext *gb, uint8_t *dst, uint8_t *src, int size)
Merge two consequent lists of equal size depending on bits read.
Definition: bink.c:217
static int flags
Definition: cpu.c:45
int url_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:280
static double c[64]
Main libavformat public API header.
#define AVERROR(e)
static AVPacket pkt
Definition: demuxing.c:52
This structure stores compressed data.
Definition: avcodec.h:1040
int64_t pts
Presentation timestamp in AVStream-&gt;time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1056