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mpl2dec.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  * MPL2 subtitles format demuxer
24  */
25 
26 #include "libavutil/intreadwrite.h"
27 
28 #include "avformat.h"
29 #include "internal.h"
30 #include "subtitles.h"
31 
32 typedef struct {
34 } MPL2Context;
35 
36 static int mpl2_probe(AVProbeData *p)
37 {
38  int i;
39  char c;
40  int64_t start, end;
41  const unsigned char *ptr = p->buf;
42  const unsigned char *ptr_end = ptr + p->buf_size;
43 
44  if (AV_RB24(ptr) == 0xefbbbf)
45  ptr += 3;
46 
47  for (i = 0; i < 2; i++) {
48  if (sscanf(ptr, "[%"SCNd64"][%"SCNd64"]%c", &start, &end, &c) != 3 &&
49  sscanf(ptr, "[%"SCNd64"][]%c", &start, &c) != 2)
50  return 0;
51  ptr += ff_subtitles_next_line(ptr);
52  if (ptr >= ptr_end)
53  return 0;
54  }
55  return AVPROBE_SCORE_MAX;
56 }
57 
58 static int read_ts(char **line, int64_t *pts_start, int *duration)
59 {
60  char c;
61  int len;
62  int64_t end;
63 
64  if (sscanf(*line, "[%"SCNd64"][]%c%n",
65  pts_start, &c, &len) >= 2) {
66  *duration = -1;
67  *line += len - 1;
68  return 0;
69  }
70  if (sscanf(*line, "[%"SCNd64"][%"SCNd64"]%c%n",
71  pts_start, &end, &c, &len) >= 3) {
72  *duration = end - *pts_start;
73  *line += len - 1;
74  return 0;
75  }
76  return -1;
77 }
78 
80 {
81  MPL2Context *mpl2 = s->priv_data;
83  int res = 0;
84 
85  if (!st)
86  return AVERROR(ENOMEM);
87  avpriv_set_pts_info(st, 64, 1, 10);
90 
91  if (avio_rb24(s->pb) != 0xefbbbf)
92  avio_seek(s->pb, -3, SEEK_CUR);
93 
94  while (!avio_feof(s->pb)) {
95  char line[4096];
96  char *p = line;
97  const int64_t pos = avio_tell(s->pb);
98  int len = ff_get_line(s->pb, line, sizeof(line));
99  int64_t pts_start;
100  int duration;
101 
102  if (!len)
103  break;
104 
105  line[strcspn(line, "\r\n")] = 0;
106 
107  if (!read_ts(&p, &pts_start, &duration)) {
108  AVPacket *sub;
109 
110  sub = ff_subtitles_queue_insert(&mpl2->q, p, strlen(p), 0);
111  if (!sub)
112  return AVERROR(ENOMEM);
113  sub->pos = pos;
114  sub->pts = pts_start;
115  sub->duration = duration;
116  }
117  }
118 
119  ff_subtitles_queue_finalize(s, &mpl2->q);
120  return res;
121 }
122 
124 {
125  MPL2Context *mpl2 = s->priv_data;
126  return ff_subtitles_queue_read_packet(&mpl2->q, pkt);
127 }
128 
129 static int mpl2_read_seek(AVFormatContext *s, int stream_index,
130  int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
131 {
132  MPL2Context *mpl2 = s->priv_data;
133  return ff_subtitles_queue_seek(&mpl2->q, s, stream_index,
134  min_ts, ts, max_ts, flags);
135 }
136 
138 {
139  MPL2Context *mpl2 = s->priv_data;
140  ff_subtitles_queue_clean(&mpl2->q);
141  return 0;
142 }
143 
145  .name = "mpl2",
146  .long_name = NULL_IF_CONFIG_SMALL("MPL2 subtitles"),
147  .priv_data_size = sizeof(MPL2Context),
151  .read_seek2 = mpl2_read_seek,
153  .extensions = "txt,mpl2",
154 };
#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:1677
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:4727
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:4074
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:235
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:1349
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:1675
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4357
int64_t duration
Definition: movenc.c:63
static int flags
Definition: log.c:57
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:527
AVInputFormat ff_mpl2_demuxer
Definition: mpl2dec.c:144
#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:179
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:4070
Definition: graph2dot.c:48
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:464
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:463
unsigned int avio_rb24(AVIOContext *s)
Definition: aviobuf.c:767
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:782
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:509
static int mpl2_read_header(AVFormatContext *s)
Definition: mpl2dec.c:79
Stream structure.
Definition: avformat.h:889
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
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_RB24
Definition: bytestream.h:87
AVIOContext * pb
I/O context.
Definition: avformat.h:1391
FFDemuxSubtitlesQueue q
Definition: mpl2dec.c:33
static int mpl2_probe(AVProbeData *p)
Definition: mpl2dec.c:36
static int mpl2_read_close(AVFormatContext *s)
Definition: mpl2dec.c:137
This structure contains the data a format has to probe a file.
Definition: avformat.h:461
static int mpl2_read_seek(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
Definition: mpl2dec.c:129
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
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:473
Main libavformat public API header.
static int mpl2_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mpl2dec.c:123
static int read_ts(char **line, int64_t *pts_start, int *duration)
Definition: mpl2dec.c:58
static double c[64]
int len
void * priv_data
Format private data.
Definition: avformat.h:1377
void INT64 start
Definition: avisynth_c.h:690
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:664
AVCodecParameters * codecpar
Definition: avformat.h:1252
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:345
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:1634
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:1650