FFmpeg  4.0
mpsubdec.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  * MPlayer subtitles format demuxer
24  */
25 
26 #include "avformat.h"
27 #include "internal.h"
28 #include "subtitles.h"
29 
30 typedef struct {
32 } MPSubContext;
33 
34 static int mpsub_probe(AVProbeData *p)
35 {
36  const char *ptr = p->buf;
37  const char *ptr_end = p->buf + p->buf_size;
38 
39  while (ptr < ptr_end) {
40  int inc;
41 
42  if (!memcmp(ptr, "FORMAT=TIME", 11))
44  if (!memcmp(ptr, "FORMAT=", 7))
45  return AVPROBE_SCORE_EXTENSION / 3;
46  inc = ff_subtitles_next_line(ptr);
47  if (!inc)
48  break;
49  ptr += inc;
50  }
51  return 0;
52 }
53 
55 {
56  MPSubContext *mpsub = s->priv_data;
57  AVStream *st;
58  AVBPrint buf;
59  AVRational pts_info = (AVRational){ 100, 1 }; // ts based by default
60  int res = 0;
61  int multiplier = 100;
62  double current_pts = 0;
63 
65 
66  while (!avio_feof(s->pb)) {
67  char line[1024];
68  double start, duration;
69  int fps, len = ff_get_line(s->pb, line, sizeof(line));
70 
71  if (!len)
72  break;
73 
74  line[strcspn(line, "\r\n")] = 0;
75 
76  if (sscanf(line, "FORMAT=%d", &fps) == 1 && fps > 3 && fps < 100) {
77  /* frame based timing */
78  pts_info = (AVRational){ fps, 1 };
79  multiplier = 1;
80  } else if (sscanf(line, "%lf %lf", &start, &duration) == 2) {
81  AVPacket *sub;
82  const int64_t pos = avio_tell(s->pb);
83 
84  ff_subtitles_read_chunk(s->pb, &buf);
85  if (buf.len) {
86  sub = ff_subtitles_queue_insert(&mpsub->q, buf.str, buf.len, 0);
87  if (!sub) {
88  res = AVERROR(ENOMEM);
89  goto end;
90  }
91  sub->pts = (int64_t)(current_pts + start*multiplier);
92  sub->duration = (int)(duration * multiplier);
93  current_pts += (start + duration) * multiplier;
94  sub->pos = pos;
95  }
96  }
97  }
98 
99  st = avformat_new_stream(s, NULL);
100  if (!st)
101  return AVERROR(ENOMEM);
102  avpriv_set_pts_info(st, 64, pts_info.den, pts_info.num);
105 
106  ff_subtitles_queue_finalize(s, &mpsub->q);
107 
108 end:
109  av_bprint_finalize(&buf, NULL);
110  return res;
111 }
112 
114 {
115  MPSubContext *mpsub = s->priv_data;
116  return ff_subtitles_queue_read_packet(&mpsub->q, pkt);
117 }
118 
119 static int mpsub_read_seek(AVFormatContext *s, int stream_index,
120  int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
121 {
122  MPSubContext *mpsub = s->priv_data;
123  return ff_subtitles_queue_seek(&mpsub->q, s, stream_index,
124  min_ts, ts, max_ts, flags);
125 }
126 
128 {
129  MPSubContext *mpsub = s->priv_data;
130  ff_subtitles_queue_clean(&mpsub->q);
131  return 0;
132 }
133 
135  .name = "mpsub",
136  .long_name = NULL_IF_CONFIG_SMALL("MPlayer subtitles"),
137  .priv_data_size = sizeof(MPSubContext),
141  .read_seek2 = mpsub_read_seek,
143  .extensions = "sub",
144 };
AVInputFormat ff_mpsub_demuxer
Definition: mpsubdec.c:134
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1450
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:4811
void ff_subtitles_read_chunk(AVIOContext *pb, AVBPrint *buf)
Same as ff_subtitles_read_text_chunk(), but read from an AVIOContext.
Definition: subtitles.c:397
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3884
int num
Numerator.
Definition: rational.h:59
static int mpsub_probe(AVProbeData *p)
Definition: mpsubdec.c:34
void ff_subtitles_queue_clean(FFDemuxSubtitlesQueue *q)
Remove and destroy all the subtitles packets.
Definition: subtitles.c:297
static AVPacket pkt
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
Definition: bprint.c:235
Format I/O context.
Definition: avformat.h:1342
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
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1448
static int mpsub_read_seek(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
Definition: mpsubdec.c:119
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4441
int64_t duration
Definition: movenc.c:63
static int flags
Definition: log.c:55
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 AV_BPRINT_SIZE_UNLIMITED
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
Definition: bprint.c:69
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3880
Definition: graph2dot.c:48
static int mpsub_read_header(AVFormatContext *s)
Definition: mpsubdec.c:54
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:451
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
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:873
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:1384
void * buf
Definition: avisynth_c.h:690
static int mpsub_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mpsubdec.c:113
Rational number (pair of numerator and denominator).
Definition: rational.h:58
static int mpsub_read_close(AVFormatContext *s)
Definition: mpsubdec.c:127
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:458
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
static av_always_inline int ff_subtitles_next_line(const char *ptr)
Get the number of characters to increment to jump to the next line, or to the end of the string...
Definition: subtitles.h:187
Main libavformat public API header.
int
raw UTF-8 text
Definition: avcodec.h:645
FFDemuxSubtitlesQueue q
Definition: mpsubdec.c:31
int den
Denominator.
Definition: rational.h:60
int len
void * priv_data
Format private data.
Definition: avformat.h:1370
void INT64 start
Definition: avisynth_c.h:690
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1020
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
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
This structure stores compressed data.
Definition: avcodec.h:1407
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:1423