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  goto fail;
85  }
86  sub = ff_subtitles_queue_insert(&aqt->q, line, strlen(line), !new_event);
87  if (!sub)
88  goto fail;
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 fail:
102  return AVERROR(ENOMEM);
103 }
104 
106 {
107  AQTitleContext *aqt = s->priv_data;
108  return ff_subtitles_queue_read_packet(&aqt->q, pkt);
109 }
110 
111 static int aqt_read_seek(AVFormatContext *s, int stream_index,
112  int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
113 {
114  AQTitleContext *aqt = s->priv_data;
115  return ff_subtitles_queue_seek(&aqt->q, s, stream_index,
116  min_ts, ts, max_ts, flags);
117 }
118 
120 {
121  AQTitleContext *aqt = s->priv_data;
123  return 0;
124 }
125 
126 #define OFFSET(x) offsetof(AQTitleContext, x)
127 #define SD AV_OPT_FLAG_SUBTITLE_PARAM|AV_OPT_FLAG_DECODING_PARAM
128 static const AVOption aqt_options[] = {
129  { "subfps", "set the movie frame rate", OFFSET(frame_rate), AV_OPT_TYPE_RATIONAL, {.dbl=25}, 0, INT_MAX, SD },
130  { NULL }
131 };
132 
133 static const AVClass aqt_class = {
134  .class_name = "aqtdec",
135  .item_name = av_default_item_name,
136  .option = aqt_options,
137  .version = LIBAVUTIL_VERSION_INT,
138 };
139 
141  .name = "aqtitle",
142  .long_name = NULL_IF_CONFIG_SMALL("AQTitle subtitles"),
143  .priv_data_size = sizeof(AQTitleContext),
147  .read_seek2 = aqt_read_seek,
149  .extensions = "aqt",
150  .priv_class = &aqt_class,
151 };
#define NULL
Definition: coverity.c:32
AVOption.
Definition: opt.h:248
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:375
#define OFFSET(x)
Definition: aqtitledec.c:126
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:4938
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int num
Numerator.
Definition: rational.h:59
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
void ff_subtitles_queue_clean(FFDemuxSubtitlesQueue *q)
Remove and destroy all the subtitles packets.
Definition: subtitles.c:302
static AVPacket pkt
static int aqt_read_header(AVFormatContext *s)
Definition: aqtitledec.c:50
static const AVOption aqt_options[]
Definition: aqtitledec.c:128
Format I/O context.
Definition: avformat.h:1351
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:119
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:212
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:373
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4519
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:153
unsigned int pos
Definition: spdifenc.c:410
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
Definition: graph2dot.c:48
#define fail()
Definition: checkasm.h:123
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
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:798
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
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:250
AVIOContext * pb
I/O context.
Definition: avformat.h:1393
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:127
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:451
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
#define flags(name, subs,...)
Definition: cbs_av1.c:560
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
static const AVClass aqt_class
Definition: aqtitledec.c:133
Main libavformat public API header.
raw UTF-8 text
Definition: codec_id.h:511
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:111
int len
void * priv_data
Format private data.
Definition: avformat.h:1379
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:650
AVInputFormat ff_aqtitle_demuxer
Definition: aqtitledec.c:140
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1023
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:368
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: packet.h:332
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:194
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:348
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
static int aqt_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: aqtitledec.c:105