FFmpeg
aqtitledec.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  * AQTitle subtitles format demuxer
24  *
25  * @see http://web.archive.org/web/20070210095721/http://www.volny.cz/aberka/czech/aqt.html
26  * @see https://trac.annodex.net/wiki/AQTitle
27  */
28 
29 #include "avformat.h"
30 #include "internal.h"
31 #include "subtitles.h"
32 #include "libavutil/opt.h"
33 
34 typedef struct {
35  const AVClass *class;
39 
40 static int aqt_probe(const AVProbeData *p)
41 {
42  int frame;
43  const char *ptr = p->buf;
44 
45  if (sscanf(ptr, "-->> %d", &frame) == 1)
47  return 0;
48 }
49 
51 {
52  AQTitleContext *aqt = s->priv_data;
54  int new_event = 1;
55  int64_t pos = 0, frame = AV_NOPTS_VALUE;
56  AVPacket *sub = NULL;
57 
58  if (!st)
59  return AVERROR(ENOMEM);
60  avpriv_set_pts_info(st, 64, aqt->frame_rate.den, aqt->frame_rate.num);
63 
64  while (!avio_feof(s->pb)) {
65  char line[4096];
66  int len = ff_get_line(s->pb, line, sizeof(line));
67 
68  if (!len)
69  break;
70 
71  line[strcspn(line, "\r\n")] = 0;
72 
73  if (sscanf(line, "-->> %"SCNd64, &frame) == 1) {
74  new_event = 1;
75  pos = avio_tell(s->pb);
76  if (sub) {
77  if (frame >= sub->pts && (uint64_t)frame - sub->pts < INT64_MAX)
78  sub->duration = frame - sub->pts;
79  sub = NULL;
80  }
81  } else if (*line) {
82  if (!new_event) {
83  sub = ff_subtitles_queue_insert(&aqt->q, "\n", 1, 1);
84  if (!sub)
85  return AVERROR(ENOMEM);
86  }
87  sub = ff_subtitles_queue_insert(&aqt->q, line, strlen(line), !new_event);
88  if (!sub)
89  return AVERROR(ENOMEM);
90  if (new_event) {
91  sub->pts = frame;
92  sub->duration = -1;
93  sub->pos = pos;
94  }
95  new_event = 0;
96  }
97  }
98 
100  return 0;
101 }
102 
104 {
105  AQTitleContext *aqt = s->priv_data;
106  return ff_subtitles_queue_read_packet(&aqt->q, pkt);
107 }
108 
109 static int aqt_read_seek(AVFormatContext *s, int stream_index,
110  int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
111 {
112  AQTitleContext *aqt = s->priv_data;
113  return ff_subtitles_queue_seek(&aqt->q, s, stream_index,
114  min_ts, ts, max_ts, flags);
115 }
116 
118 {
119  AQTitleContext *aqt = s->priv_data;
121  return 0;
122 }
123 
124 #define OFFSET(x) offsetof(AQTitleContext, x)
125 #define SD AV_OPT_FLAG_SUBTITLE_PARAM|AV_OPT_FLAG_DECODING_PARAM
126 static const AVOption aqt_options[] = {
127  { "subfps", "set the movie frame rate", OFFSET(frame_rate), AV_OPT_TYPE_RATIONAL, {.dbl=25}, 0, INT_MAX, SD },
128  { NULL }
129 };
130 
131 static const AVClass aqt_class = {
132  .class_name = "aqtdec",
133  .item_name = av_default_item_name,
134  .option = aqt_options,
135  .version = LIBAVUTIL_VERSION_INT,
136 };
137 
139  .name = "aqtitle",
140  .long_name = NULL_IF_CONFIG_SMALL("AQTitle subtitles"),
141  .priv_data_size = sizeof(AQTitleContext),
142  .flags_internal = FF_FMT_INIT_CLEANUP,
146  .read_seek2 = aqt_read_seek,
148  .extensions = "aqt",
149  .priv_class = &aqt_class,
150 };
AVMEDIA_TYPE_SUBTITLE
@ AVMEDIA_TYPE_SUBTITLE
Definition: avutil.h:204
FF_FMT_INIT_CLEANUP
#define FF_FMT_INIT_CLEANUP
For an AVInputFormat with this flag set read_close() needs to be called by the caller upon read_heade...
Definition: internal.h:46
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AVOption
AVOption.
Definition: opt.h:251
AQTitleContext::q
FFDemuxSubtitlesQueue q
Definition: aqtitledec.c:36
AQTitleContext
Definition: aqtitledec.c:34
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:540
aqt_read_header
static int aqt_read_header(AVFormatContext *s)
Definition: aqtitledec.c:50
AV_OPT_TYPE_RATIONAL
@ AV_OPT_TYPE_RATIONAL
Definition: opt.h:230
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:830
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:513
AVRational::num
int num
Numerator.
Definition: rational.h:59
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:261
pkt
AVPacket * pkt
Definition: movenc.c:59
AVInputFormat
Definition: avformat.h:549
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:41
s
#define s(width, name)
Definition: cbs_vp9.c:198
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:554
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:454
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:222
frame
static AVFrame * frame
Definition: demux_decode.c:54
aqt_options
static const AVOption aqt_options[]
Definition: aqtitledec.c:126
AVFormatContext
Format I/O context.
Definition: avformat.h:1202
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:864
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
NULL
#define NULL
Definition: coverity.c:32
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:452
aqt_read_seek
static int aqt_read_seek(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
Definition: aqtitledec.c:109
ff_subtitles_queue_insert
AVPacket * ff_subtitles_queue_insert(FFDemuxSubtitlesQueue *q, const uint8_t *event, size_t len, int merge)
Insert a new subtitle event.
Definition: subtitles.c:109
aqt_probe
static int aqt_probe(const AVProbeData *p)
Definition: aqtitledec.c:40
AVPROBE_SCORE_EXTENSION
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:462
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:106
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:204
FFDemuxSubtitlesQueue
Definition: subtitles.h:103
aqt_class
static const AVClass aqt_class
Definition: aqtitledec.c:131
AQTitleContext::frame_rate
AVRational frame_rate
Definition: aqtitledec.c:37
ff_subtitles_queue_clean
void ff_subtitles_queue_clean(FFDemuxSubtitlesQueue *q)
Remove and destroy all the subtitles packets.
Definition: subtitles.c:313
line
Definition: graph2dot.c:48
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:515
ff_get_line
int ff_get_line(AVIOContext *s, char *buf, int maxlen)
Read a whole line of text from AVIOContext.
Definition: aviobuf.c:816
len
int len
Definition: vorbis_enc_data.h:426
AVStream
Stream structure.
Definition: avformat.h:841
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:413
avformat.h
AV_CODEC_ID_TEXT
@ AV_CODEC_ID_TEXT
raw UTF-8 text
Definition: codec_id.h:554
subtitles.h
AVRational::den
int den
Denominator.
Definition: rational.h:60
aqt_read_packet
static int aqt_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: aqtitledec.c:103
SD
#define SD
Definition: aqtitledec.c:125
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:29
aqt_read_close
static int aqt_read_close(AVFormatContext *s)
Definition: aqtitledec.c:117
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:499
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:542
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
OFFSET
#define OFFSET(x)
Definition: aqtitledec.c:124
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:393
ff_aqtitle_demuxer
const AVInputFormat ff_aqtitle_demuxer
Definition: aqtitledec.c:138