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  sub->duration = frame - sub->pts;
78  sub = NULL;
79  }
80  } else if (*line) {
81  if (!new_event) {
82  sub = ff_subtitles_queue_insert(&aqt->q, "\n", 1, 1);
83  if (!sub)
84  return AVERROR(ENOMEM);
85  }
86  sub = ff_subtitles_queue_insert(&aqt->q, line, strlen(line), !new_event);
87  if (!sub)
88  return AVERROR(ENOMEM);
89  if (new_event) {
90  sub->pts = frame;
91  sub->duration = -1;
92  sub->pos = pos;
93  }
94  new_event = 0;
95  }
96  }
97 
99  return 0;
100 }
101 
103 {
104  AQTitleContext *aqt = s->priv_data;
105  return ff_subtitles_queue_read_packet(&aqt->q, pkt);
106 }
107 
108 static int aqt_read_seek(AVFormatContext *s, int stream_index,
109  int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
110 {
111  AQTitleContext *aqt = s->priv_data;
112  return ff_subtitles_queue_seek(&aqt->q, s, stream_index,
113  min_ts, ts, max_ts, flags);
114 }
115 
117 {
118  AQTitleContext *aqt = s->priv_data;
120  return 0;
121 }
122 
123 #define OFFSET(x) offsetof(AQTitleContext, x)
124 #define SD AV_OPT_FLAG_SUBTITLE_PARAM|AV_OPT_FLAG_DECODING_PARAM
125 static const AVOption aqt_options[] = {
126  { "subfps", "set the movie frame rate", OFFSET(frame_rate), AV_OPT_TYPE_RATIONAL, {.dbl=25}, 0, INT_MAX, SD },
127  { NULL }
128 };
129 
130 static const AVClass aqt_class = {
131  .class_name = "aqtdec",
132  .item_name = av_default_item_name,
133  .option = aqt_options,
134  .version = LIBAVUTIL_VERSION_INT,
135 };
136 
138  .name = "aqtitle",
139  .long_name = NULL_IF_CONFIG_SMALL("AQTitle subtitles"),
140  .priv_data_size = sizeof(AQTitleContext),
144  .read_seek2 = aqt_read_seek,
146  .extensions = "aqt",
147  .priv_class = &aqt_class,
148 };
#define NULL
Definition: coverity.c:32
AVOption.
Definition: opt.h:246
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1497
#define OFFSET(x)
Definition: aqtitledec.c:123
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:4882
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3953
int num
Numerator.
Definition: rational.h:59
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
void ff_subtitles_queue_clean(FFDemuxSubtitlesQueue *q)
Remove and destroy all the subtitles packets.
Definition: subtitles.c:297
static AVPacket pkt
static int aqt_read_header(AVFormatContext *s)
Definition: aqtitledec.c:50
static const AVOption aqt_options[]
Definition: aqtitledec.c:125
Format I/O context.
Definition: avformat.h:1358
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:72
static int aqt_read_close(AVFormatContext *s)
Definition: aqtitledec.c:116
AVOptions.
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
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1495
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4455
AVRational frame_rate
Definition: aqtitledec.c:37
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:557
FFDemuxSubtitlesQueue q
Definition: aqtitledec.c:36
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3949
Definition: graph2dot.c:48
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
#define s(width, name)
Definition: cbs_vp9.c:257
int ff_get_line(AVIOContext *s, char *buf, int maxlen)
Read a whole line of text from AVIOContext.
Definition: aviobuf.c:809
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
Stream structure.
Definition: avformat.h:881
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
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
Describe the class of an AVClass context structure.
Definition: log.h:67
Rational number (pair of numerator and denominator).
Definition: rational.h:58
#define SD
Definition: aqtitledec.c:124
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:456
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
#define flags(name, subs,...)
Definition: cbs_av1.c:561
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
static const AVClass aqt_class
Definition: aqtitledec.c:130
Main libavformat public API header.
raw UTF-8 text
Definition: avcodec.h:660
int den
Denominator.
Definition: rational.h:60
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:108
int len
void * priv_data
Format private data.
Definition: avformat.h:1386
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
AVInputFormat ff_aqtitle_demuxer
Definition: aqtitledec.c:137
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:358
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
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
This structure stores compressed data.
Definition: avcodec.h:1454
static int aqt_probe(const AVProbeData *p)
Definition: aqtitledec.c:40
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:1470
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
static int aqt_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: aqtitledec.c:102