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stldec.c
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1 /*
2  * Copyright (c) 2014 Eejya Singh
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  * STL subtitles format demuxer
24  * @see https://documentation.apple.com/en/dvdstudiopro/usermanual/index.html#chapter=19%26section=13%26tasks=true
25  */
26 
27 #include "avformat.h"
28 #include "internal.h"
29 #include "subtitles.h"
30 #include "libavutil/intreadwrite.h"
31 #include "libavutil/avstring.h"
32 
33 typedef struct {
35 } STLContext;
36 
37 static int stl_probe(AVProbeData *p)
38 {
39  char c;
40  const unsigned char *ptr = p->buf;
41 
42  if (AV_RB24(ptr) == 0xEFBBBF)
43  ptr += 3; /* skip UTF-8 BOM */
44 
45  while (*ptr == '\r' || *ptr == '\n' || *ptr == '$' || !strncmp(ptr, "//" , 2))
46  ptr += ff_subtitles_next_line(ptr);
47 
48  if (sscanf(ptr, "%*d:%*d:%*d:%*d , %*d:%*d:%*d:%*d , %c", &c) == 1)
49  return AVPROBE_SCORE_MAX;
50 
51  return 0;
52 }
53 
54 static int64_t get_pts(char **buf, int *duration)
55 {
56  int hh1, mm1, ss1, ms1;
57  int hh2, mm2, ss2, ms2;
58  int len = 0;
59 
60  if (sscanf(*buf, "%2d:%2d:%2d:%2d , %2d:%2d:%2d:%2d , %n",
61  &hh1, &mm1, &ss1, &ms1,
62  &hh2, &mm2, &ss2, &ms2, &len) >= 8 && len > 0) {
63  int64_t start = (hh1*3600LL + mm1*60LL + ss1) * 100LL + ms1;
64  int64_t end = (hh2*3600LL + mm2*60LL + ss2) * 100LL + ms2;
65  *duration = end - start;
66  *buf += len;
67  return start;
68  }
69  return AV_NOPTS_VALUE;
70 }
71 
73 {
74  STLContext *stl = s->priv_data;
76 
77  if (!st)
78  return AVERROR(ENOMEM);
79  avpriv_set_pts_info(st, 64, 1, 100);
82 
83  while (!avio_feof(s->pb)) {
84  char line[4096];
85  char *p = line;
86  const int64_t pos = avio_tell(s->pb);
87  int len = ff_get_line(s->pb, line, sizeof(line));
88  int64_t pts_start;
89  int duration;
90 
91  if (!len)
92  break;
93 
94  line[strcspn(line, "\r\n")] = 0;
95  pts_start = get_pts(&p , &duration);
96 
97  if (pts_start != AV_NOPTS_VALUE) {
98  AVPacket *sub;
99  sub = ff_subtitles_queue_insert(&stl->q, p, strlen(p), 0);
100  if (!sub)
101  return AVERROR(ENOMEM);
102  sub->pos = pos;
103  sub->pts = pts_start;
104  sub->duration = duration;
105  }
106  }
107  ff_subtitles_queue_finalize(s, &stl->q);
108  return 0;
109 }
111 {
112  STLContext *stl = s->priv_data;
113  return ff_subtitles_queue_read_packet(&stl->q, pkt);
114 }
115 
116 static int stl_read_seek(AVFormatContext *s, int stream_index,
117  int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
118 {
119  STLContext *stl = s->priv_data;
120  return ff_subtitles_queue_seek(&stl->q, s, stream_index,
121  min_ts, ts, max_ts, flags);
122 }
123 
125 {
126  STLContext *stl = s->priv_data;
128  return 0;
129 }
130 
132  .name = "stl",
133  .long_name = NULL_IF_CONFIG_SMALL("Spruce subtitle format"),
134  .priv_data_size = sizeof(STLContext),
138  .read_seek2 = stl_read_seek,
140  .extensions = "stl",
141 };
#define NULL
Definition: coverity.c:32
AVInputFormat ff_stl_demuxer
Definition: stldec.c:131
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1465
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
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3900
void ff_subtitles_queue_clean(FFDemuxSubtitlesQueue *q)
Remove and destroy all the subtitles packets.
Definition: subtitles.c:297
static AVPacket pkt
static int64_t get_pts(char **buf, int *duration)
Definition: stldec.c:54
Format I/O context.
Definition: avformat.h:1351
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:1463
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4455
int64_t duration
Definition: movenc.c:63
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
static int stl_read_seek(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
Definition: stldec.c:116
static int stl_probe(AVProbeData *p)
Definition: stldec.c:37
static int stl_read_close(AVFormatContext *s)
Definition: stldec.c:124
static int stl_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: stldec.c:110
#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
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3896
Definition: graph2dot.c:48
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
FFDemuxSubtitlesQueue q
Definition: stldec.c:34
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
#define stl(l, p)
Definition: asm.h:76
#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 read_header(FFV1Context *f)
Definition: ffv1dec.c:530
Stream structure.
Definition: avformat.h:874
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:1393
void * buf
Definition: avisynth_c.h:690
static int stl_read_header(AVFormatContext *s)
Definition: stldec.c:72
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
#define flags(name, subs,...)
Definition: cbs_av1.c:596
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:460
Main libavformat public API header.
static double c[64]
int len
void * priv_data
Format private data.
Definition: avformat.h:1379
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:1021
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:1422
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:1438
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248