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subviewerdec.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  * SubViewer subtitle demuxer
24  * @see https://en.wikipedia.org/wiki/SubViewer
25  */
26 
27 #include "avformat.h"
28 #include "internal.h"
29 #include "subtitles.h"
30 #include "libavcodec/internal.h"
31 #include "libavutil/avstring.h"
32 #include "libavutil/bprint.h"
33 #include "libavutil/intreadwrite.h"
34 
35 typedef struct {
38 
40 {
41  char c;
42  const unsigned char *ptr = p->buf;
43 
44  if (AV_RB24(ptr) == 0xEFBBBF)
45  ptr += 3; /* skip UTF-8 BOM */
46  if (sscanf(ptr, "%*u:%*u:%*u.%*u,%*u:%*u:%*u.%*u%c", &c) == 1)
48  if (!strncmp(ptr, "[INFORMATION]", 13))
49  return AVPROBE_SCORE_MAX/3;
50  return 0;
51 }
52 
53 static int read_ts(const char *s, int64_t *start, int *duration)
54 {
55  int64_t end;
56  int hh1, mm1, ss1, ms1;
57  int hh2, mm2, ss2, ms2;
58 
59  if (sscanf(s, "%u:%u:%u.%u,%u:%u:%u.%u",
60  &hh1, &mm1, &ss1, &ms1, &hh2, &mm2, &ss2, &ms2) == 8) {
61  end = (hh2*3600LL + mm2*60LL + ss2) * 100LL + ms2;
62  *start = (hh1*3600LL + mm1*60LL + ss1) * 100LL + ms1;
63  *duration = end - *start;
64  return 0;
65  }
66  return -1;
67 }
68 
70 {
71  SubViewerContext *subviewer = s->priv_data;
73  AVBPrint header;
74  int res = 0, new_event = 1;
75  int64_t pts_start = AV_NOPTS_VALUE;
76  int duration = -1;
77  AVPacket *sub = NULL;
78 
79  if (!st)
80  return AVERROR(ENOMEM);
81  avpriv_set_pts_info(st, 64, 1, 100);
84 
86 
87  while (!avio_feof(s->pb)) {
88  char line[2048];
89  int64_t pos = 0;
90  int len = ff_get_line(s->pb, line, sizeof(line));
91 
92  if (!len)
93  break;
94 
95  line[strcspn(line, "\r\n")] = 0;
96 
97  if (line[0] == '[' && strncmp(line, "[br]", 4)) {
98 
99  /* ignore event style, XXX: add to side_data? */
100  if (strstr(line, "[COLF]") || strstr(line, "[SIZE]") ||
101  strstr(line, "[FONT]") || strstr(line, "[STYLE]"))
102  continue;
103 
104  if (!st->codecpar->extradata) { // header not finalized yet
105  av_bprintf(&header, "%s\n", line);
106  if (!strncmp(line, "[END INFORMATION]", 17) || !strncmp(line, "[SUBTITLE]", 10)) {
107  /* end of header */
108  res = ff_bprint_to_codecpar_extradata(st->codecpar, &header);
109  if (res < 0)
110  goto end;
111  } else if (strncmp(line, "[INFORMATION]", 13)) {
112  /* assume file metadata at this point */
113  int i, j = 0;
114  char key[32], value[128];
115 
116  for (i = 1; i < sizeof(key) - 1 && line[i] && line[i] != ']'; i++)
117  key[i - 1] = av_tolower(line[i]);
118  key[i - 1] = 0;
119 
120  if (line[i] == ']')
121  i++;
122  while (line[i] == ' ')
123  i++;
124  while (j < sizeof(value) - 1 && line[i] && line[i] != ']')
125  value[j++] = line[i++];
126  value[j] = 0;
127 
128  av_dict_set(&s->metadata, key, value, 0);
129  }
130  }
131  } else if (read_ts(line, &pts_start, &duration) >= 0) {
132  new_event = 1;
133  pos = avio_tell(s->pb);
134  } else if (*line) {
135  if (!new_event) {
136  sub = ff_subtitles_queue_insert(&subviewer->q, "\n", 1, 1);
137  if (!sub) {
138  res = AVERROR(ENOMEM);
139  goto end;
140  }
141  }
142  sub = ff_subtitles_queue_insert(&subviewer->q, line, strlen(line), !new_event);
143  if (!sub) {
144  res = AVERROR(ENOMEM);
145  goto end;
146  }
147  if (new_event) {
148  sub->pos = pos;
149  sub->pts = pts_start;
150  sub->duration = duration;
151  }
152  new_event = 0;
153  }
154  }
155 
156  ff_subtitles_queue_finalize(s, &subviewer->q);
157 
158 end:
159  av_bprint_finalize(&header, NULL);
160  return res;
161 }
162 
164 {
165  SubViewerContext *subviewer = s->priv_data;
166  return ff_subtitles_queue_read_packet(&subviewer->q, pkt);
167 }
168 
169 static int subviewer_read_seek(AVFormatContext *s, int stream_index,
170  int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
171 {
172  SubViewerContext *subviewer = s->priv_data;
173  return ff_subtitles_queue_seek(&subviewer->q, s, stream_index,
174  min_ts, ts, max_ts, flags);
175 }
176 
178 {
179  SubViewerContext *subviewer = s->priv_data;
180  ff_subtitles_queue_clean(&subviewer->q);
181  return 0;
182 }
183 
185  .name = "subviewer",
186  .long_name = NULL_IF_CONFIG_SMALL("SubViewer subtitle format"),
187  .priv_data_size = sizeof(SubViewerContext),
191  .read_seek2 = subviewer_read_seek,
193  .extensions = "sub",
194 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:631
void av_bprintf(AVBPrint *buf, const char *fmt,...)
Definition: bprint.c:94
static int subviewer_read_seek(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
Definition: subviewerdec.c:169
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1608
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:4493
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3939
void ff_subtitles_queue_clean(FFDemuxSubtitlesQueue *q)
Remove and destroy all the subtitles packets.
Definition: subtitles.c:297
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:1325
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:1606
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4131
int64_t duration
Definition: movenc.c:63
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:511
static const uint8_t header[24]
Definition: sdr2.c:67
static av_const int av_tolower(int c)
Locale-independent conversion of ASCII characters to lowercase.
Definition: avstring.h:241
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1539
#define AV_BPRINT_SIZE_UNLIMITED
#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:3935
Definition: graph2dot.c:48
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:461
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:109
static int subviewer_probe(AVProbeData *p)
Definition: subviewerdec.c:39
int ff_get_line(AVIOContext *s, char *buf, int maxlen)
Read a whole line of text from AVIOContext.
Definition: aviobuf.c:759
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
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_RB24
Definition: bytestream.h:87
AVIOContext * pb
I/O context.
Definition: avformat.h:1367
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:69
int ff_bprint_to_codecpar_extradata(AVCodecParameters *par, struct AVBPrint *buf)
Finalize buf into extradata and set its size appropriately.
Definition: utils.c:5252
#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 int read_ts(const char *s, int64_t *start, int *duration)
Definition: subviewerdec.c:53
static int flags
Definition: cpu.c:47
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:471
Main libavformat public API header.
common internal api header.
static double c[64]
static int subviewer_read_header(AVFormatContext *s)
Definition: subviewerdec.c:69
AVInputFormat ff_subviewer_demuxer
Definition: subviewerdec.c:184
int len
static int subviewer_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: subviewerdec.c:163
void * priv_data
Format private data.
Definition: avformat.h:1353
static int subviewer_read_close(AVFormatContext *s)
Definition: subviewerdec.c:177
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:3953
FFDemuxSubtitlesQueue q
Definition: subviewerdec.c:36
void INT64 start
Definition: avisynth_c.h:553
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:660
AVCodecParameters * codecpar
Definition: avformat.h:1228
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:328
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:1565
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:1581
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:240