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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 "avformat.h"
27 #include "internal.h"
28 #include "subtitles.h"
29 
30 typedef struct {
32 } MPL2Context;
33 
34 static int mpl2_probe(AVProbeData *p)
35 {
36  int i;
37  char c;
38  int64_t start, end;
39  const unsigned char *ptr = p->buf;
40  const unsigned char *ptr_end = ptr + p->buf_size;
41 
42  for (i = 0; i < 2; i++) {
43  if (sscanf(ptr, "[%"SCNd64"][%"SCNd64"]%c", &start, &end, &c) != 3 &&
44  sscanf(ptr, "[%"SCNd64"][]%c", &start, &c) != 2)
45  return 0;
46  ptr += ff_subtitles_next_line(ptr);
47  if (ptr >= ptr_end)
48  return 0;
49  }
50  return AVPROBE_SCORE_MAX;
51 }
52 
53 static int read_ts(char **line, int64_t *pts_start, int *duration)
54 {
55  char c;
56  int len;
57  int64_t end;
58 
59  if (sscanf(*line, "[%"SCNd64"][]%c%n",
60  pts_start, &c, &len) >= 2) {
61  *duration = -1;
62  *line += len - 1;
63  return 0;
64  }
65  if (sscanf(*line, "[%"SCNd64"][%"SCNd64"]%c%n",
66  pts_start, &end, &c, &len) >= 3) {
67  *duration = end - *pts_start;
68  *line += len - 1;
69  return 0;
70  }
71  return -1;
72 }
73 
75 {
76  MPL2Context *mpl2 = s->priv_data;
78  int res = 0;
79 
80  if (!st)
81  return AVERROR(ENOMEM);
82  avpriv_set_pts_info(st, 64, 1, 10);
85 
86  while (!avio_feof(s->pb)) {
87  char line[4096];
88  char *p = line;
89  const int64_t pos = avio_tell(s->pb);
90  int len = ff_get_line(s->pb, line, sizeof(line));
91  int64_t pts_start;
92  int duration;
93 
94  if (!len)
95  break;
96 
97  line[strcspn(line, "\r\n")] = 0;
98 
99  if (!read_ts(&p, &pts_start, &duration)) {
100  AVPacket *sub;
101 
102  sub = ff_subtitles_queue_insert(&mpl2->q, p, strlen(p), 0);
103  if (!sub)
104  return AVERROR(ENOMEM);
105  sub->pos = pos;
106  sub->pts = pts_start;
107  sub->duration = duration;
108  }
109  }
110 
111  ff_subtitles_queue_finalize(s, &mpl2->q);
112  return res;
113 }
114 
116 {
117  MPL2Context *mpl2 = s->priv_data;
118  return ff_subtitles_queue_read_packet(&mpl2->q, pkt);
119 }
120 
121 static int mpl2_read_seek(AVFormatContext *s, int stream_index,
122  int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
123 {
124  MPL2Context *mpl2 = s->priv_data;
125  return ff_subtitles_queue_seek(&mpl2->q, s, stream_index,
126  min_ts, ts, max_ts, flags);
127 }
128 
130 {
131  MPL2Context *mpl2 = s->priv_data;
132  ff_subtitles_queue_clean(&mpl2->q);
133  return 0;
134 }
135 
137  .name = "mpl2",
138  .long_name = NULL_IF_CONFIG_SMALL("MPL2 subtitles"),
139  .priv_data_size = sizeof(MPL2Context),
143  .read_seek2 = mpl2_read_seek,
145  .extensions = "txt,mpl2",
146 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:631
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1487
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:4149
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:1314
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:1485
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3805
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:442
AVInputFormat ff_mpl2_demuxer
Definition: mpl2dec.c:136
#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:176
Definition: graph2dot.c:48
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:896
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:463
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:462
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
int64_t duration
Definition: movenc-test.c:63
int ff_get_line(AVIOContext *s, char *buf, int maxlen)
Read a whole line of text from AVIOContext.
Definition: aviobuf.c:706
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:638
static int mpl2_read_header(AVFormatContext *s)
Definition: mpl2dec.c:74
Stream structure.
Definition: avformat.h:877
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
enum AVMediaType codec_type
Definition: avcodec.h:1540
enum AVCodecID codec_id
Definition: avcodec.h:1549
AVIOContext * pb
I/O context.
Definition: avformat.h:1356
FFDemuxSubtitlesQueue q
Definition: mpl2dec.c:31
static int mpl2_probe(AVProbeData *p)
Definition: mpl2dec.c:34
static int mpl2_read_close(AVFormatContext *s)
Definition: mpl2dec.c:129
This structure contains the data a format has to probe a file.
Definition: avformat.h:460
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:121
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
static int flags
Definition: cpu.c:47
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:472
Main libavformat public API header.
static int mpl2_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mpl2dec.c:115
static int read_ts(char **line, int64_t *pts_start, int *duration)
Definition: mpl2dec.c:53
static double c[64]
int len
void * priv_data
Format private data.
Definition: avformat.h:1342
void INT64 start
Definition: avisynth_c.h:553
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:661
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:306
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:1444
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:1460