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samidec.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  * SAMI subtitle demuxer
24  * @see http://msdn.microsoft.com/en-us/library/ms971327.aspx
25  */
26 
27 #include "avformat.h"
28 #include "internal.h"
29 #include "subtitles.h"
30 #include "libavcodec/internal.h"
31 #include "libavutil/avstring.h"
32 #include "libavutil/bprint.h"
33 #include "libavutil/intreadwrite.h"
34 
35 typedef struct {
37 } SAMIContext;
38 
39 static int sami_probe(AVProbeData *p)
40 {
41  char buf[6];
42  FFTextReader tr;
43  ff_text_init_buf(&tr, p->buf, p->buf_size);
44  ff_text_read(&tr, buf, sizeof(buf));
45 
46  return !strncmp(buf, "<SAMI>", 6) ? AVPROBE_SCORE_MAX : 0;
47 }
48 
50 {
51  SAMIContext *sami = s->priv_data;
53  AVBPrint buf, hdr_buf;
54  char c = 0;
55  int res = 0, got_first_sync_point = 0;
56  FFTextReader tr;
57  ff_text_init_avio(s, &tr, s->pb);
58 
59  if (!st)
60  return AVERROR(ENOMEM);
61  avpriv_set_pts_info(st, 64, 1, 1000);
64 
67 
68  while (!ff_text_eof(&tr)) {
69  AVPacket *sub;
70  const int64_t pos = ff_text_pos(&tr) - (c != 0);
71  int is_sync, is_body, n = ff_smil_extract_next_text_chunk(&tr, &buf, &c);
72 
73  if (n == 0)
74  break;
75 
76  is_body = !av_strncasecmp(buf.str, "</BODY", 6);
77  if (is_body) {
78  av_bprint_clear(&buf);
79  break;
80  }
81 
82  is_sync = !av_strncasecmp(buf.str, "<SYNC", 5);
83  if (is_sync)
84  got_first_sync_point = 1;
85 
86  if (!got_first_sync_point) {
87  av_bprintf(&hdr_buf, "%s", buf.str);
88  } else {
89  sub = ff_subtitles_queue_insert(&sami->q, buf.str, buf.len, !is_sync);
90  if (!sub) {
91  res = AVERROR(ENOMEM);
92  goto end;
93  }
94  if (is_sync) {
95  const char *p = ff_smil_get_attr_ptr(buf.str, "Start");
96  sub->pos = pos;
97  sub->pts = p ? strtol(p, NULL, 10) : 0;
98  sub->duration = -1;
99  }
100  }
101  av_bprint_clear(&buf);
102  }
103 
104  res = ff_bprint_to_codecpar_extradata(st->codecpar, &hdr_buf);
105  if (res < 0)
106  goto end;
107 
108  ff_subtitles_queue_finalize(s, &sami->q);
109 
110 end:
111  av_bprint_finalize(&buf, NULL);
112  return res;
113 }
114 
116 {
117  SAMIContext *sami = s->priv_data;
118  return ff_subtitles_queue_read_packet(&sami->q, pkt);
119 }
120 
121 static int sami_read_seek(AVFormatContext *s, int stream_index,
122  int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
123 {
124  SAMIContext *sami = s->priv_data;
125  return ff_subtitles_queue_seek(&sami->q, s, stream_index,
126  min_ts, ts, max_ts, flags);
127 }
128 
130 {
131  SAMIContext *sami = s->priv_data;
132  ff_subtitles_queue_clean(&sami->q);
133  return 0;
134 }
135 
137  .name = "sami",
138  .long_name = NULL_IF_CONFIG_SMALL("SAMI subtitle format"),
139  .priv_data_size = sizeof(SAMIContext),
143  .read_seek2 = sami_read_seek,
145  .extensions = "smi,sami",
146 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
void av_bprintf(AVBPrint *buf, const char *fmt,...)
Definition: bprint.c:94
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1610
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:4504
static int sami_read_seek(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
Definition: samidec.c:121
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3953
void ff_subtitles_queue_clean(FFDemuxSubtitlesQueue *q)
Remove and destroy all the subtitles packets.
Definition: subtitles.c:297
int av_strncasecmp(const char *a, const char *b, size_t n)
Locale-independent case-insensitive compare.
Definition: avstring.c:223
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:1327
const char * ff_smil_get_attr_ptr(const char *s, const char *attr)
SMIL helper to point on the value of an attribute in the given tag.
Definition: subtitles.c:330
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:1608
AVInputFormat ff_sami_demuxer
Definition: samidec.c:136
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4137
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
#define AV_BPRINT_SIZE_UNLIMITED
int ff_text_eof(FFTextReader *r)
Return non-zero if EOF was reached.
Definition: subtitles.c:92
#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
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:3949
void ff_text_init_avio(void *s, FFTextReader *r, AVIOContext *pb)
Initialize the FFTextReader from the given AVIOContext.
Definition: subtitles.c:27
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
int64_t ff_text_pos(FFTextReader *r)
Return the byte position of the next byte returned by ff_text_r8().
Definition: subtitles.c:60
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
static int sami_probe(AVProbeData *p)
Definition: samidec.c:39
int n
Definition: avisynth_c.h:684
void ff_text_read(FFTextReader *r, char *buf, size_t size)
Read the given number of bytes (in UTF-8).
Definition: subtitles.c:86
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:514
Stream structure.
Definition: avformat.h:878
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
int ff_smil_extract_next_text_chunk(FFTextReader *tr, AVBPrint *buf, char *c)
SMIL helper to load next chunk ("<...>" or untagged content) in buf.
Definition: subtitles.c:307
static int sami_read_header(AVFormatContext *s)
Definition: samidec.c:49
AVIOContext * pb
I/O context.
Definition: avformat.h:1369
void * buf
Definition: avisynth_c.h:690
int ff_bprint_to_codecpar_extradata(AVCodecParameters *par, struct AVBPrint *buf)
Finalize buf into extradata and set its size appropriately.
Definition: utils.c:5257
This structure contains the data a format has to probe a file.
Definition: avformat.h:461
static int flags
Definition: cpu.c:47
void av_bprint_clear(AVBPrint *buf)
Reset the string to "" but keep internal allocated data.
Definition: bprint.c:227
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:473
Main libavformat public API header.
common internal api header.
static double c[64]
void ff_text_init_buf(FFTextReader *r, void *buf, size_t size)
Similar to ff_text_init_avio(), but sets it up to read from a bounded buffer.
Definition: subtitles.c:53
static int sami_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: samidec.c:115
static int sami_read_close(AVFormatContext *s)
Definition: samidec.c:129
void * priv_data
Format private data.
Definition: avformat.h:1355
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:662
AVCodecParameters * codecpar
Definition: avformat.h:1230
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:1567
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:1583
FFDemuxSubtitlesQueue q
Definition: samidec.c:36