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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  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 
48 static int 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*3600 + mm*60 + ss) * 100 + ms;
53  if (sscanf(s, "%u:%u:%u" , &hh, &mm, &ss ) == 3) return (hh*3600 + mm*60 + ss) * 100;
54  if (sscanf(s, "%u:%u.%u", &mm, &ss, &ms) == 3) return ( mm*60 + ss) * 100 + ms;
55  if (sscanf(s, "%u:%u" , &mm, &ss ) == 2) return ( mm*60 + ss) * 100;
56  if (sscanf(s, "%u.%u", &ss, &ms) == 2) return ( ss) * 100 + ms;
57  return strtol(s, NULL, 10) * 100;
58 }
59 
61 {
62  RealTextContext *rt = s->priv_data;
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);
75 
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 (p)
91  duration = read_ts(p);
92  st->codecpar->extradata = av_strdup(buf.str);
93  if (!st->codecpar->extradata) {
94  res = AVERROR(ENOMEM);
95  goto end;
96  }
97  st->codecpar->extradata_size = buf.len + 1;
98  } else {
99  /* if we just read a <time> tag, introduce a new event, otherwise merge
100  * with the previous one */
101  int merge = !av_strncasecmp(buf.str, "<time", 5) ? 0 : 1;
102  sub = ff_subtitles_queue_insert(&rt->q, buf.str, buf.len, merge);
103  if (!sub) {
104  res = AVERROR(ENOMEM);
105  goto end;
106  }
107  if (!merge) {
108  const char *begin = ff_smil_get_attr_ptr(buf.str, "begin");
109  const char *end = ff_smil_get_attr_ptr(buf.str, "end");
110 
111  sub->pos = pos;
112  sub->pts = begin ? read_ts(begin) : 0;
113  sub->duration = end ? (read_ts(end) - sub->pts) : duration;
114  }
115  }
116  av_bprint_clear(&buf);
117  }
119 
120 end:
121  av_bprint_finalize(&buf, NULL);
122  return res;
123 }
124 
126 {
127  RealTextContext *rt = s->priv_data;
128  return ff_subtitles_queue_read_packet(&rt->q, pkt);
129 }
130 
131 static int realtext_read_seek(AVFormatContext *s, int stream_index,
132  int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
133 {
134  RealTextContext *rt = s->priv_data;
135  return ff_subtitles_queue_seek(&rt->q, s, stream_index,
136  min_ts, ts, max_ts, flags);
137 }
138 
140 {
141  RealTextContext *rt = s->priv_data;
143  return 0;
144 }
145 
147  .name = "realtext",
148  .long_name = NULL_IF_CONFIG_SMALL("RealText subtitle format"),
149  .priv_data_size = sizeof(RealTextContext),
153  .read_seek2 = realtext_read_seek,
155  .extensions = "rt",
156 };
static int realtext_read_close(AVFormatContext *s)
Definition: realtextdec.c:139
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:631
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1594
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:4402
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3911
static int realtext_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: realtextdec.c:125
static int read_ts(const char *s)
Definition: realtextdec.c:48
void ff_subtitles_queue_clean(FFDemuxSubtitlesQueue *q)
Remove and destroy all the subtitles packets.
Definition: subtitles.c:297
int av_strncasecmp(const char *a, const char *b, size_t n)
Locale-independent case-insensitive compare.
Definition: avstring.c:223
static AVPacket pkt
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
Definition: bprint.c:235
Format I/O context.
Definition: avformat.h:1319
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:330
int ff_subtitles_queue_read_packet(FFDemuxSubtitlesQueue *q, AVPacket *pkt)
Generic read_packet() callback for subtitles demuxers using this queue system.
Definition: subtitles.c:208
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1592
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4040
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
FFDemuxSubtitlesQueue q
Definition: realtextdec.c:35
#define AV_BPRINT_SIZE_UNLIMITED
int ff_text_eof(FFTextReader *r)
Return non-zero if EOF was reached.
Definition: subtitles.c:92
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
Definition: bprint.c:69
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3907
void ff_text_init_avio(void *s, FFTextReader *r, AVIOContext *pb)
Initialize the FFTextReader from the given AVIOContext.
Definition: subtitles.c:27
int extradata_size
Size of the extradata content in bytes.
Definition: avcodec.h:3929
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:462
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:461
int64_t ff_text_pos(FFTextReader *r)
Return the byte position of the next byte returned by ff_text_r8().
Definition: subtitles.c:60
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:131
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
static int realtext_read_header(AVFormatContext *s)
Definition: realtextdec.c:60
int64_t duration
Definition: movenc-test.c:63
int n
Definition: avisynth_c.h:547
void ff_text_read(FFTextReader *r, char *buf, size_t size)
Read the given number of bytes (in UTF-8).
Definition: subtitles.c:86
static int realtext_probe(AVProbeData *p)
Definition: realtextdec.c:38
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:638
Stream structure.
Definition: avformat.h:876
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
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:245
int ff_smil_extract_next_text_chunk(FFTextReader *tr, AVBPrint *buf, char *c)
SMIL helper to load next chunk ("<...>" or untagged content) in buf.
Definition: subtitles.c:307
char * av_strdup(const char *s)
Duplicate the string s.
Definition: mem.c:267
AVIOContext * pb
I/O context.
Definition: avformat.h:1361
#define ss
AVInputFormat ff_realtext_demuxer
Definition: realtextdec.c:146
void * buf
Definition: avisynth_c.h:553
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:469
This structure contains the data a format has to probe a file.
Definition: avformat.h:459
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:47
void av_bprint_clear(AVBPrint *buf)
Reset the string to "" but keep internal allocated data.
Definition: bprint.c:227
Main libavformat public API header.
static double c[64]
void ff_text_init_buf(FFTextReader *r, void *buf, size_t size)
Similar to ff_text_init_avio(), but sets it up to read from a bounded buffer.
Definition: subtitles.c:53
void * priv_data
Format private data.
Definition: avformat.h:1347
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:3925
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:660
AVCodecParameters * codecpar
Definition: avformat.h:1006
AVPacket * ff_subtitles_queue_insert(FFDemuxSubtitlesQueue *q, const uint8_t *event, size_t len, int merge)
Insert a new subtitle event.
Definition: subtitles.c:111
This structure stores compressed data.
Definition: avcodec.h:1551
void ff_subtitles_queue_finalize(void *log_ctx, FFDemuxSubtitlesQueue *q)
Set missing durations, sort subtitles by PTS (and then byte position), and drop duplicated events...
Definition: subtitles.c:193
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1567