FFmpeg
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(const 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 
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  res = AVERROR(ENOMEM);
102  goto end;
103  }
104  avpriv_set_pts_info(st, 64, pts_info.den, pts_info.num);
107 
108  ff_subtitles_queue_finalize(s, &mpsub->q);
109 
110 end:
111  if (res < 0)
112  ff_subtitles_queue_clean(&mpsub->q);
113 
115  return res;
116 }
117 
119 {
120  MPSubContext *mpsub = s->priv_data;
121  return ff_subtitles_queue_read_packet(&mpsub->q, pkt);
122 }
123 
124 static int mpsub_read_seek(AVFormatContext *s, int stream_index,
125  int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
126 {
127  MPSubContext *mpsub = s->priv_data;
128  return ff_subtitles_queue_seek(&mpsub->q, s, stream_index,
129  min_ts, ts, max_ts, flags);
130 }
131 
133 {
134  MPSubContext *mpsub = s->priv_data;
135  ff_subtitles_queue_clean(&mpsub->q);
136  return 0;
137 }
138 
140  .name = "mpsub",
141  .long_name = NULL_IF_CONFIG_SMALL("MPlayer subtitles"),
142  .priv_data_size = sizeof(MPSubContext),
146  .read_seek2 = mpsub_read_seek,
148  .extensions = "sub",
149 };
AVMEDIA_TYPE_SUBTITLE
@ AVMEDIA_TYPE_SUBTITLE
Definition: avutil.h:204
AV_BPRINT_SIZE_UNLIMITED
#define AV_BPRINT_SIZE_UNLIMITED
AVERROR
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4480
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3953
av_bprint_finalize
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
Definition: bprint.c:235
av_bprint_init
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
Definition: bprint.c:69
end
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1495
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:449
mpsub_read_close
static int mpsub_read_close(AVFormatContext *s)
Definition: mpsubdec.c:132
start
void INT64 start
Definition: avisynth_c.h:767
read_close
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
AVRational::num
int num
Numerator.
Definition: rational.h:59
ff_subtitles_queue_seek
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:249
buf
void * buf
Definition: avisynth_c.h:766
AVInputFormat
Definition: avformat.h:640
MPSubContext
Definition: mpsubdec.c:30
duration
int64_t duration
Definition: movenc.c:63
MPSubContext::q
FFDemuxSubtitlesQueue q
Definition: mpsubdec.c:31
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:645
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
mpsub_read_packet
static int mpsub_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mpsubdec.c:118
mpsub_read_header
static int mpsub_read_header(AVFormatContext *s)
Definition: mpsubdec.c:54
ff_subtitles_queue_read_packet
int ff_subtitles_queue_read_packet(FFDemuxSubtitlesQueue *q, AVPacket *pkt)
Generic read_packet() callback for subtitles demuxers using this queue system.
Definition: subtitles.c:212
AVFormatContext
Format I/O context.
Definition: avformat.h:1342
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1017
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
NULL
#define NULL
Definition: coverity.c:32
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
ff_subtitles_queue_insert
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
AVPROBE_SCORE_EXTENSION
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:456
mpsub_read_seek
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:124
ff_mpsub_demuxer
AVInputFormat ff_mpsub_demuxer
Definition: mpsubdec.c:139
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:188
mpsub_probe
static int mpsub_probe(const AVProbeData *p)
Definition: mpsubdec.c:34
avpriv_set_pts_info
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:4910
ff_subtitles_queue_finalize
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:194
FFDemuxSubtitlesQueue
Definition: subtitles.h:102
ff_subtitles_queue_clean
void ff_subtitles_queue_clean(FFDemuxSubtitlesQueue *q)
Remove and destroy all the subtitles packets.
Definition: subtitles.c:301
line
Definition: graph2dot.c:48
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1470
ff_get_line
int ff_get_line(AVIOContext *s, char *buf, int maxlen)
Read a whole line of text from AVIOContext.
Definition: aviobuf.c:808
len
int len
Definition: vorbis_enc_data.h:452
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVStream
Stream structure.
Definition: avformat.h:870
ff_subtitles_read_chunk
void ff_subtitles_read_chunk(AVIOContext *pb, AVBPrint *buf)
Same as ff_subtitles_read_text_chunk(), but read from an AVIOContext.
Definition: subtitles.c:401
avformat.h
AV_CODEC_ID_TEXT
@ AV_CODEC_ID_TEXT
raw UTF-8 text
Definition: avcodec.h:660
subtitles.h
pkt
static AVPacket pkt
Definition: demuxing_decoding.c:54
AVRational::den
int den
Denominator.
Definition: rational.h:60
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3957
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1454
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1497
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:565
ff_subtitles_next_line
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
int
int
Definition: ffmpeg_filter.c:191
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:358