FFmpeg
tedcaptionsdec.c
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1 /*
2  * TED Talks captions format decoder
3  * Copyright (c) 2012 Nicolas George
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/bprint.h"
23 #include "libavutil/log.h"
24 #include "libavutil/opt.h"
25 #include "avformat.h"
26 #include "demux.h"
27 #include "internal.h"
28 #include "subtitles.h"
29 
30 typedef struct {
31  AVClass *class;
32  int64_t start_time;
35 
36 static const AVOption tedcaptions_options[] = {
37  { "start_time", "set the start time (offset) of the subtitles, in ms",
39  { .i64 = 15000 }, INT64_MIN, INT64_MAX,
41  { NULL },
42 };
43 
45  .class_name = "tedcaptions_demuxer",
46  .item_name = av_default_item_name,
47  .option = tedcaptions_options,
48  .version = LIBAVUTIL_VERSION_INT,
49 };
50 
51 #define BETWEEN(a, amin, amax) ((unsigned)((a) - (amin)) <= (amax) - (amin))
52 
53 #define HEX_DIGIT_TEST(c) (BETWEEN(c, '0', '9') || BETWEEN((c) | 32, 'a', 'z'))
54 #define HEX_DIGIT_VAL(c) ((c) <= '9' ? (c) - '0' : ((c) | 32) - 'a' + 10)
55 #define ERR_CODE(c) ((c) < 0 ? (c) : AVERROR_INVALIDDATA)
56 
57 static void av_bprint_utf8(AVBPrint *bp, unsigned c)
58 {
59  int bytes, i;
60 
61  if (c <= 0x7F) {
62  av_bprint_chars(bp, c, 1);
63  return;
64  }
65  bytes = (av_log2(c) - 2) / 5;
66  av_bprint_chars(bp, (c >> (bytes * 6)) | ((0xFF80 >> bytes) & 0xFF), 1);
67  for (i = bytes - 1; i >= 0; i--)
68  av_bprint_chars(bp, ((c >> (i * 6)) & 0x3F) | 0x80, 1);
69 }
70 
71 static void next_byte(AVIOContext *pb, int *cur_byte)
72 {
73  uint8_t b;
74  int ret = avio_read(pb, &b, 1);
75  *cur_byte = ret > 0 ? b : ret == 0 ? AVERROR_EOF : ret;
76 }
77 
78 static void skip_spaces(AVIOContext *pb, int *cur_byte)
79 {
80  while (*cur_byte == ' ' || *cur_byte == '\t' ||
81  *cur_byte == '\n' || *cur_byte == '\r')
82  next_byte(pb, cur_byte);
83 }
84 
85 static int expect_byte(AVIOContext *pb, int *cur_byte, uint8_t c)
86 {
87  skip_spaces(pb, cur_byte);
88  if (*cur_byte != c)
89  return ERR_CODE(*cur_byte);
90  next_byte(pb, cur_byte);
91  return 0;
92 }
93 
94 static int parse_string(AVIOContext *pb, int *cur_byte, AVBPrint *bp, int full)
95 {
96  int ret;
97 
98  ret = expect_byte(pb, cur_byte, '"');
99  if (ret < 0)
100  return ret;
101  while (*cur_byte > 0 && *cur_byte != '"') {
102  if (*cur_byte == '\\') {
103  next_byte(pb, cur_byte);
104  if (*cur_byte < 0)
105  return AVERROR_INVALIDDATA;
106  if ((*cur_byte | 32) == 'u') {
107  unsigned chr = 0, i;
108  for (i = 0; i < 4; i++) {
109  next_byte(pb, cur_byte);
110  if (!HEX_DIGIT_TEST(*cur_byte))
111  return ERR_CODE(*cur_byte);
112  chr = chr * 16 + HEX_DIGIT_VAL(*cur_byte);
113  }
114  av_bprint_utf8(bp, chr);
115  } else {
116  av_bprint_chars(bp, *cur_byte, 1);
117  }
118  } else {
119  av_bprint_chars(bp, *cur_byte, 1);
120  }
121  next_byte(pb, cur_byte);
122  }
123  ret = expect_byte(pb, cur_byte, '"');
124  if (ret < 0)
125  return ret;
126  if (full && !av_bprint_is_complete(bp))
127  return AVERROR(ENOMEM);
128 
129  return 0;
130 }
131 
132 static int parse_label(AVIOContext *pb, int *cur_byte, AVBPrint *bp)
133 {
134  int ret;
135 
137  ret = parse_string(pb, cur_byte, bp, 0);
138  if (ret < 0)
139  return ret;
140  ret = expect_byte(pb, cur_byte, ':');
141  if (ret < 0)
142  return ret;
143  return 0;
144 }
145 
146 static int parse_boolean(AVIOContext *pb, int *cur_byte, int *result)
147 {
148  static const char * const text[] = { "false", "true" };
149  const char *p;
150  int i;
151 
152  skip_spaces(pb, cur_byte);
153  for (i = 0; i < 2; i++) {
154  p = text[i];
155  if (*cur_byte != *p)
156  continue;
157  for (; *p; p++, next_byte(pb, cur_byte))
158  if (*cur_byte != *p)
159  return AVERROR_INVALIDDATA;
160  if (BETWEEN(*cur_byte | 32, 'a', 'z'))
161  return AVERROR_INVALIDDATA;
162  *result = i;
163  return 0;
164  }
165  return AVERROR_INVALIDDATA;
166 }
167 
168 static int parse_int(AVIOContext *pb, int *cur_byte, int64_t *result)
169 {
170  int64_t val = 0;
171 
172  skip_spaces(pb, cur_byte);
173  if ((unsigned)*cur_byte - '0' > 9)
174  return AVERROR_INVALIDDATA;
175  while (BETWEEN(*cur_byte, '0', '9')) {
176  if (val > INT_MAX/10 - (*cur_byte - '0'))
177  return AVERROR_INVALIDDATA;
178  val = val * 10 + (*cur_byte - '0');
179  next_byte(pb, cur_byte);
180  }
181  *result = val;
182  return 0;
183 }
184 
186 {
187  int ret, cur_byte, start_of_par;
188  AVBPrint label, content;
189  int64_t pos, start, duration;
190  AVPacket *pkt;
191 
193 
194  next_byte(pb, &cur_byte);
195  ret = expect_byte(pb, &cur_byte, '{');
196  if (ret < 0)
197  return AVERROR_INVALIDDATA;
198  ret = parse_label(pb, &cur_byte, &label);
199  if (ret < 0 || strcmp(label.str, "captions"))
200  return AVERROR_INVALIDDATA;
201  ret = expect_byte(pb, &cur_byte, '[');
202  if (ret < 0)
203  return AVERROR_INVALIDDATA;
204  while (1) {
205  start = duration = AV_NOPTS_VALUE;
206  ret = expect_byte(pb, &cur_byte, '{');
207  if (ret < 0)
208  goto fail;
209  pos = avio_tell(pb) - 1;
210  while (1) {
211  ret = parse_label(pb, &cur_byte, &label);
212  if (ret < 0)
213  goto fail;
214  if (!strcmp(label.str, "startOfParagraph")) {
215  ret = parse_boolean(pb, &cur_byte, &start_of_par);
216  if (ret < 0)
217  goto fail;
218  } else if (!strcmp(label.str, "content")) {
219  ret = parse_string(pb, &cur_byte, &content, 1);
220  if (ret < 0)
221  goto fail;
222  } else if (!strcmp(label.str, "startTime")) {
223  ret = parse_int(pb, &cur_byte, &start);
224  if (ret < 0)
225  goto fail;
226  } else if (!strcmp(label.str, "duration")) {
227  ret = parse_int(pb, &cur_byte, &duration);
228  if (ret < 0)
229  goto fail;
230  } else {
232  goto fail;
233  }
234  skip_spaces(pb, &cur_byte);
235  if (cur_byte != ',')
236  break;
237  next_byte(pb, &cur_byte);
238  }
239  ret = expect_byte(pb, &cur_byte, '}');
240  if (ret < 0)
241  goto fail;
242 
243  if (!content.size || start == AV_NOPTS_VALUE ||
246  goto fail;
247  }
248  pkt = ff_subtitles_queue_insert_bprint(subs, &content, 0);
249  if (!pkt) {
250  ret = AVERROR(ENOMEM);
251  goto fail;
252  }
253  pkt->pos = pos;
254  pkt->pts = start;
255  pkt->duration = duration;
256  av_bprint_clear(&content);
257 
258  skip_spaces(pb, &cur_byte);
259  if (cur_byte != ',')
260  break;
261  next_byte(pb, &cur_byte);
262  }
263  ret = expect_byte(pb, &cur_byte, ']');
264  if (ret < 0)
265  goto fail;
266  ret = expect_byte(pb, &cur_byte, '}');
267  if (ret < 0)
268  goto fail;
269  skip_spaces(pb, &cur_byte);
270  if (cur_byte != AVERROR_EOF)
271  ret = ERR_CODE(cur_byte);
272 fail:
273  av_bprint_finalize(&content, NULL);
274  return ret;
275 }
276 
278 {
280  AVStream *st = avformat_new_stream(avf, NULL);
281  FFStream *sti;
282  int ret, i;
283  AVPacket *last;
284 
285  if (!st)
286  return AVERROR(ENOMEM);
287 
288  sti = ffstream(st);
289  ret = parse_file(avf->pb, &tc->subs);
290  if (ret < 0) {
291  if (ret == AVERROR_INVALIDDATA)
292  av_log(avf, AV_LOG_ERROR, "Syntax error near offset %"PRId64".\n",
293  avio_tell(avf->pb));
294  return ret;
295  }
296  ff_subtitles_queue_finalize(avf, &tc->subs);
297  for (i = 0; i < tc->subs.nb_subs; i++)
298  tc->subs.subs[i]->pts += tc->start_time;
299 
300  last = tc->subs.subs[tc->subs.nb_subs - 1];
303  avpriv_set_pts_info(st, 64, 1, 1000);
304  sti->probe_packets = 0;
305  st->start_time = 0;
306  st->duration = last->pts + last->duration;
307  sti->cur_dts = 0;
308 
309  return 0;
310 }
311 
313 {
315 
316  return ff_subtitles_queue_read_packet(&tc->subs, packet);
317 }
318 
320 {
322 
324  return 0;
325 }
326 
328 {
329  static const char *const tags[] = {
330  "\"captions\"", "\"duration\"", "\"content\"",
331  "\"startOfParagraph\"", "\"startTime\"",
332  };
333  unsigned i, count = 0;
334  const char *t;
335 
336  if (p->buf[strspn(p->buf, " \t\r\n")] != '{')
337  return 0;
338  for (i = 0; i < FF_ARRAY_ELEMS(tags); i++) {
339  if (!(t = strstr(p->buf, tags[i])))
340  continue;
341  t += strlen(tags[i]);
342  t += strspn(t, " \t\r\n");
343  if (*t == ':')
344  count++;
345  }
346  return count == FF_ARRAY_ELEMS(tags) ? AVPROBE_SCORE_MAX :
347  count ? AVPROBE_SCORE_EXTENSION : 0;
348 }
349 
350 static int tedcaptions_read_seek(AVFormatContext *avf, int stream_index,
351  int64_t min_ts, int64_t ts, int64_t max_ts,
352  int flags)
353 {
355  return ff_subtitles_queue_seek(&tc->subs, avf, stream_index,
356  min_ts, ts, max_ts, flags);
357 }
358 
360  .p.name = "tedcaptions",
361  .p.long_name = NULL_IF_CONFIG_SMALL("TED Talks captions"),
362  .p.priv_class = &tedcaptions_demuxer_class,
363  .priv_data_size = sizeof(TEDCaptionsDemuxer),
364  .flags_internal = FF_INFMT_FLAG_INIT_CLEANUP,
369  .read_seek2 = tedcaptions_read_seek,
370 };
skip_spaces
static void skip_spaces(AVIOContext *pb, int *cur_byte)
Definition: tedcaptionsdec.c:78
AVMEDIA_TYPE_SUBTITLE
@ AVMEDIA_TYPE_SUBTITLE
Definition: avutil.h:204
AV_BPRINT_SIZE_UNLIMITED
#define AV_BPRINT_SIZE_UNLIMITED
av_bprint_is_complete
static int av_bprint_is_complete(const AVBPrint *buf)
Test if the print buffer is complete (not truncated).
Definition: bprint.h:218
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
opt.h
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
tedcaptions_options
static const AVOption tedcaptions_options[]
Definition: tedcaptionsdec.c:36
av_bprint_init
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
Definition: bprint.c:69
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
ff_tedcaptions_demuxer
const FFInputFormat ff_tedcaptions_demuxer
Definition: tedcaptionsdec.c:359
tedcaptions_read_seek
static int tedcaptions_read_seek(AVFormatContext *avf, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
Definition: tedcaptionsdec.c:350
AVOption
AVOption.
Definition: opt.h:357
b
#define b
Definition: input.c:41
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:542
ERR_CODE
#define ERR_CODE(c)
Definition: tedcaptionsdec.c:55
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:463
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:853
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:417
fail
#define fail()
Definition: checkasm.h:182
TEDCaptionsDemuxer::start_time
int64_t start_time
Definition: tedcaptionsdec.c:32
read_close
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:143
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:494
AV_BPRINT_SIZE_AUTOMATIC
#define AV_BPRINT_SIZE_AUTOMATIC
val
static double val(void *priv, double ch)
Definition: aeval.c:78
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:802
ff_subtitles_queue_seek
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:269
pkt
AVPacket * pkt
Definition: movenc.c:60
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
FF_ARRAY_ELEMS
#define FF_ARRAY_ELEMS(a)
Definition: sinewin_tablegen.c:29
av_cold
#define av_cold
Definition: attributes.h:90
HEX_DIGIT_VAL
#define HEX_DIGIT_VAL(c)
Definition: tedcaptionsdec.c:54
duration
int64_t duration
Definition: movenc.c:65
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:42
TEDCaptionsDemuxer
Definition: tedcaptionsdec.c:30
tedcaptions_demuxer_class
static const AVClass tedcaptions_demuxer_class
Definition: tedcaptionsdec.c:44
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:553
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
AV_OPT_TYPE_INT64
@ AV_OPT_TYPE_INT64
Definition: opt.h:246
TEDCaptionsDemuxer::subs
FFDemuxSubtitlesQueue subs
Definition: tedcaptionsdec.c:33
ff_subtitles_queue_read_packet
int ff_subtitles_queue_read_packet(FFDemuxSubtitlesQueue *q, AVPacket *pkt)
Generic read_packet() callback for subtitles demuxers using this queue system.
Definition: subtitles.c:230
FF_INFMT_FLAG_INIT_CLEANUP
#define FF_INFMT_FLAG_INIT_CLEANUP
For an FFInputFormat with this flag set read_close() needs to be called by the caller upon read_heade...
Definition: demux.h:35
AVFormatContext
Format I/O context.
Definition: avformat.h:1255
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:766
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:550
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
result
and forward the result(frame or status change) to the corresponding input. If nothing is possible
NULL
#define NULL
Definition: coverity.c:32
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1297
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
tedcaptions_read_packet
static int tedcaptions_read_packet(AVFormatContext *avf, AVPacket *packet)
Definition: tedcaptionsdec.c:312
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AVPROBE_SCORE_EXTENSION
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:461
HEX_DIGIT_TEST
#define HEX_DIGIT_TEST(c)
Definition: tedcaptionsdec.c:53
AVIOContext
Bytestream IO Context.
Definition: avio.h:160
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:94
av_bprint_finalize
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
Definition: bprint.c:240
FFStream
Definition: internal.h:193
start_time
static int64_t start_time
Definition: ffplay.c:326
AV_NOPTS_VALUE
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
ff_subtitles_queue_finalize
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:212
av_bprint_utf8
static void av_bprint_utf8(AVBPrint *bp, unsigned c)
Definition: tedcaptionsdec.c:57
FFDemuxSubtitlesQueue
Definition: subtitles.h:103
FFInputFormat::p
AVInputFormat p
The public AVInputFormat.
Definition: demux.h:41
ff_subtitles_queue_clean
void ff_subtitles_queue_clean(FFDemuxSubtitlesQueue *q)
Remove and destroy all the subtitles packets.
Definition: subtitles.c:321
tedcaptions_read_probe
static av_cold int tedcaptions_read_probe(const AVProbeData *p)
Definition: tedcaptionsdec.c:327
FFStream::probe_packets
int probe_packets
Number of packets to buffer for codec probing.
Definition: internal.h:383
parse_string
static int parse_string(AVIOContext *pb, int *cur_byte, AVBPrint *bp, int full)
Definition: tedcaptionsdec.c:94
ff_subtitles_queue_insert_bprint
AVPacket * ff_subtitles_queue_insert_bprint(FFDemuxSubtitlesQueue *q, const AVBPrint *event, int merge)
Same as ff_subtitles_queue_insert but takes an AVBPrint input.
Definition: subtitles.c:156
parse_int
static int parse_int(AVIOContext *pb, int *cur_byte, int64_t *result)
Definition: tedcaptionsdec.c:168
bprint.h
log.h
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:517
expect_byte
static int expect_byte(AVIOContext *pb, int *cur_byte, uint8_t c)
Definition: tedcaptionsdec.c:85
AV_OPT_FLAG_SUBTITLE_PARAM
#define AV_OPT_FLAG_SUBTITLE_PARAM
Definition: opt.h:287
next_byte
static void next_byte(AVIOContext *pb, int *cur_byte)
Definition: tedcaptionsdec.c:71
demux.h
tedcaptions_read_close
static int tedcaptions_read_close(AVFormatContext *avf)
Definition: tedcaptionsdec.c:319
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:743
AVClass::class_name
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:71
pos
unsigned int pos
Definition: spdifenc.c:414
avformat.h
AV_CODEC_ID_TEXT
@ AV_CODEC_ID_TEXT
raw UTF-8 text
Definition: codec_id.h:552
subtitles.h
av_bprint_clear
void av_bprint_clear(AVBPrint *buf)
Reset the string to "" but keep internal allocated data.
Definition: bprint.c:232
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:612
parse_file
static int parse_file(AVIOContext *pb, FFDemuxSubtitlesQueue *subs)
Definition: tedcaptionsdec.c:185
parse_boolean
static int parse_boolean(AVIOContext *pb, int *cur_byte, int *result)
Definition: tedcaptionsdec.c:146
tc
#define tc
Definition: regdef.h:69
AV_OPT_FLAG_DECODING_PARAM
#define AV_OPT_FLAG_DECODING_PARAM
A generic parameter which can be set by the user for demuxing or decoding.
Definition: opt.h:284
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:30
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:501
FFStream::cur_dts
int64_t cur_dts
Definition: internal.h:410
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:544
FFInputFormat
Definition: demux.h:37
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
av_bprint_chars
void av_bprint_chars(AVBPrint *buf, char c, unsigned n)
Append char c n times to a print buffer.
Definition: bprint.c:145
AVStream::start_time
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:792
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1283
parse_label
static int parse_label(AVIOContext *pb, int *cur_byte, AVBPrint *bp)
Definition: tedcaptionsdec.c:132
av_log2
int av_log2(unsigned v)
Definition: intmath.c:26
tedcaptions_read_header
static av_cold int tedcaptions_read_header(AVFormatContext *avf)
Definition: tedcaptionsdec.c:277
BETWEEN
#define BETWEEN(a, amin, amax)
Definition: tedcaptionsdec.c:51