FFmpeg
subviewer1dec.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 v1 subtitle demuxer
24  */
25 
26 #include "avformat.h"
27 #include "internal.h"
28 #include "subtitles.h"
29 
30 typedef struct {
33 
34 static int subviewer1_probe(const AVProbeData *p)
35 {
36  const unsigned char *ptr = p->buf;
37 
38  if (strstr(ptr, "******** START SCRIPT ********"))
40  return 0;
41 }
42 
44 {
45  int delay = 0;
46  AVPacket *sub = NULL;
47  SubViewer1Context *subviewer1 = s->priv_data;
49 
50  if (!st)
51  return AVERROR(ENOMEM);
52  avpriv_set_pts_info(st, 64, 1, 1);
55 
56  while (!avio_feof(s->pb)) {
57  char line[4096];
58  int len = ff_get_line(s->pb, line, sizeof(line));
59  int hh, mm, ss;
60 
61  if (!len)
62  break;
63 
64  if (!strncmp(line, "[DELAY]", 7)) {
65  ff_get_line(s->pb, line, sizeof(line));
66  sscanf(line, "%d", &delay);
67  }
68 
69  if (sscanf(line, "[%d:%d:%d]", &hh, &mm, &ss) == 3) {
70  const int64_t pos = avio_tell(s->pb);
71  int64_t pts_start = hh*3600LL + mm*60LL + ss + delay;
72 
73  len = ff_get_line(s->pb, line, sizeof(line));
74  line[strcspn(line, "\r\n")] = 0;
75  if (!*line) {
76  if (sub)
77  sub->duration = pts_start - sub->pts;
78  } else {
79  sub = ff_subtitles_queue_insert(&subviewer1->q, line, len, 0);
80  if (!sub)
81  return AVERROR(ENOMEM);
82  sub->pos = pos;
83  sub->pts = pts_start;
84  sub->duration = -1;
85  }
86  }
87  }
88 
89  ff_subtitles_queue_finalize(s, &subviewer1->q);
90  return 0;
91 }
92 
94 {
95  SubViewer1Context *subviewer1 = s->priv_data;
96  return ff_subtitles_queue_read_packet(&subviewer1->q, pkt);
97 }
98 
99 static int subviewer1_read_seek(AVFormatContext *s, int stream_index,
100  int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
101 {
102  SubViewer1Context *subviewer1 = s->priv_data;
103  return ff_subtitles_queue_seek(&subviewer1->q, s, stream_index,
104  min_ts, ts, max_ts, flags);
105 }
106 
108 {
109  SubViewer1Context *subviewer1 = s->priv_data;
110  ff_subtitles_queue_clean(&subviewer1->q);
111  return 0;
112 }
113 
115  .name = "subviewer1",
116  .long_name = NULL_IF_CONFIG_SMALL("SubViewer v1 subtitle format"),
117  .priv_data_size = sizeof(SubViewer1Context),
121  .read_seek2 = subviewer1_read_seek,
123  .extensions = "sub",
124 };
#define NULL
Definition: coverity.c:32
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1497
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
static int subviewer1_read_close(AVFormatContext *s)
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3953
static int subviewer1_read_header(AVFormatContext *s)
Definition: subviewer1dec.c:43
void ff_subtitles_queue_clean(FFDemuxSubtitlesQueue *q)
Remove and destroy all the subtitles packets.
Definition: subtitles.c:297
static AVPacket pkt
Format I/O context.
Definition: avformat.h:1358
static int subviewer1_read_seek(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
Definition: subviewer1dec.c:99
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
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
#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
static int subviewer1_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: subviewer1dec.c:93
Definition: graph2dot.c:48
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
#define ss(width, name, subs,...)
Definition: cbs_vp9.c:261
#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 subviewer1_probe(const AVProbeData *p)
Definition: subviewer1dec.c:34
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
AVInputFormat ff_subviewer1_demuxer
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
#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
Main libavformat public API header.
int len
FFDemuxSubtitlesQueue q
Definition: subviewer1dec.c:31
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
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
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