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microdvddec.c
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1 /*
2  * MicroDVD subtitle demuxer
3  * Copyright (c) 2010 Aurelien Jacobs <aurel@gnuage.org>
4  * Copyright (c) 2012 Clément Bœsch <u pkh me>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include "avformat.h"
24 #include "internal.h"
25 #include "subtitles.h"
26 #include "libavutil/intreadwrite.h"
27 #include "libavutil/opt.h"
28 
29 #define MAX_LINESIZE 2048
30 
31 
32 typedef struct {
33  const AVClass *class;
37 
38 
40 {
41  unsigned char c;
42  const uint8_t *ptr = p->buf;
43  int i;
44 
45  if (AV_RB24(ptr) == 0xEFBBBF)
46  ptr += 3; /* skip UTF-8 BOM */
47 
48  for (i=0; i<3; i++) {
49  if (sscanf(ptr, "{%*d}{}%c", &c) != 1 &&
50  sscanf(ptr, "{%*d}{%*d}%c", &c) != 1 &&
51  sscanf(ptr, "{DEFAULT}{}%c", &c) != 1)
52  return 0;
53  ptr += ff_subtitles_next_line(ptr);
54  }
55  return AVPROBE_SCORE_MAX;
56 }
57 
58 static int64_t get_pts(const char *buf)
59 {
60  int frame;
61  char c;
62 
63  if (sscanf(buf, "{%d}{%c", &frame, &c) == 2)
64  return frame;
65  return AV_NOPTS_VALUE;
66 }
67 
68 static int get_duration(const char *buf)
69 {
71 
72  if (sscanf(buf, "{%d}{%d}", &frame_start, &frame_end) == 2)
73  return frame_end - frame_start;
74  return -1;
75 }
76 
77 static const char *bom = "\xEF\xBB\xBF";
78 
80 {
81  AVRational pts_info = (AVRational){ 2997, 125 }; /* default: 23.976 fps */
82  MicroDVDContext *microdvd = s->priv_data;
84  int i = 0;
85  char line_buf[MAX_LINESIZE];
86  int has_real_fps = 0;
87 
88  if (!st)
89  return AVERROR(ENOMEM);
90 
91  while (!avio_feof(s->pb)) {
92  char *p;
93  AVPacket *sub;
94  int64_t pos = avio_tell(s->pb);
95  int len = ff_get_line(s->pb, line_buf, sizeof(line_buf));
96  char *line = line_buf;
97 
98  if (!strncmp(line, bom, 3))
99  line += 3;
100  p = line;
101 
102  if (!len)
103  break;
104  line[strcspn(line, "\r\n")] = 0;
105  if (i++ < 3) {
106  int frame;
107  double fps;
108  char c;
109 
110  if ((sscanf(line, "{%d}{}%6lf", &frame, &fps) == 2 ||
111  sscanf(line, "{%d}{%*d}%6lf", &frame, &fps) == 2)
112  && frame <= 1 && fps > 3 && fps < 100) {
113  pts_info = av_d2q(fps, 100000);
114  has_real_fps = 1;
115  continue;
116  }
117  if (!st->codecpar->extradata && sscanf(line, "{DEFAULT}{}%c", &c) == 1) {
118  st->codecpar->extradata = av_strdup(line + 11);
119  if (!st->codecpar->extradata)
120  return AVERROR(ENOMEM);
121  st->codecpar->extradata_size = strlen(st->codecpar->extradata) + 1;
122  continue;
123  }
124  }
125 #define SKIP_FRAME_ID \
126  p = strchr(p, '}'); \
127  if (!p) { \
128  av_log(s, AV_LOG_WARNING, "Invalid event \"%s\"" \
129  " at line %d\n", line, i); \
130  continue; \
131  } \
132  p++
135  if (!*p)
136  continue;
137  sub = ff_subtitles_queue_insert(&microdvd->q, p, strlen(p), 0);
138  if (!sub)
139  return AVERROR(ENOMEM);
140  sub->pos = pos;
141  sub->pts = get_pts(line);
142  sub->duration = get_duration(line);
143  }
144  ff_subtitles_queue_finalize(s, &microdvd->q);
145  if (has_real_fps) {
146  /* export the FPS info only if set in the file */
147  microdvd->frame_rate = pts_info;
148  } else if (microdvd->frame_rate.num) {
149  /* fallback on user specified frame rate */
150  pts_info = microdvd->frame_rate;
151  }
152  avpriv_set_pts_info(st, 64, pts_info.den, pts_info.num);
155  return 0;
156 }
157 
159 {
160  MicroDVDContext *microdvd = s->priv_data;
161  return ff_subtitles_queue_read_packet(&microdvd->q, pkt);
162 }
163 
164 static int microdvd_read_seek(AVFormatContext *s, int stream_index,
165  int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
166 {
167  MicroDVDContext *microdvd = s->priv_data;
168  return ff_subtitles_queue_seek(&microdvd->q, s, stream_index,
169  min_ts, ts, max_ts, flags);
170 }
171 
173 {
174  MicroDVDContext *microdvd = s->priv_data;
175  ff_subtitles_queue_clean(&microdvd->q);
176  return 0;
177 }
178 
179 
180 #define OFFSET(x) offsetof(MicroDVDContext, x)
181 #define SD AV_OPT_FLAG_SUBTITLE_PARAM|AV_OPT_FLAG_DECODING_PARAM
182 static const AVOption microdvd_options[] = {
183  { "subfps", "set the movie frame rate fallback", OFFSET(frame_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX, SD },
184  { NULL }
185 };
186 
187 static const AVClass microdvd_class = {
188  .class_name = "microdvddec",
189  .item_name = av_default_item_name,
190  .option = microdvd_options,
191  .version = LIBAVUTIL_VERSION_INT,
192 };
193 
195  .name = "microdvd",
196  .long_name = NULL_IF_CONFIG_SMALL("MicroDVD subtitle format"),
197  .priv_data_size = sizeof(MicroDVDContext),
201  .read_seek2 = microdvd_read_seek,
203  .priv_class = &microdvd_class,
204 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
static int microdvd_read_seek(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
Definition: microdvddec.c:164
AVOption.
Definition: opt.h:245
#define LIBAVUTIL_VERSION_INT
Definition: version.h:70
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
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3953
int num
Numerator.
Definition: rational.h:59
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:1327
static int microdvd_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: microdvddec.c:158
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
#define OFFSET(x)
Definition: microdvddec.c:180
uint8_t
AVOptions.
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
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1608
#define SD
Definition: microdvddec.c:181
#define MAX_LINESIZE
Definition: microdvddec.c:29
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4137
static AVFrame * frame
static int64_t get_pts(const char *buf)
Definition: microdvddec.c:58
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:511
static const char * bom
Definition: microdvddec.c:77
av_default_item_name
#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
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3949
Definition: graph2dot.c:48
static int microdvd_read_header(AVFormatContext *s)
Definition: microdvddec.c:79
int extradata_size
Size of the extradata content in bytes.
Definition: avcodec.h:3971
static void frame_end(MpegEncContext *s)
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:463
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
AVInputFormat ff_microdvd_demuxer
Definition: microdvddec.c:194
static const AVClass microdvd_class
Definition: microdvddec.c:187
int ff_get_line(AVIOContext *s, char *buf, int maxlen)
Read a whole line of text from AVIOContext.
Definition: aviobuf.c:765
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
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:267
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:1369
static int frame_start(MpegEncContext *s)
void * buf
Definition: avisynth_c.h:690
FFDemuxSubtitlesQueue q
Definition: microdvddec.c:34
Describe the class of an AVClass context structure.
Definition: log.h:67
Rational number (pair of numerator and denominator).
Definition: rational.h:58
This structure contains the data a format has to probe a file.
Definition: avformat.h:461
#define SKIP_FRAME_ID
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
AVRational av_d2q(double d, int max)
Convert a double precision floating point number to a rational.
Definition: rational.c:106
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:473
static const AVOption microdvd_options[]
Definition: microdvddec.c:182
Main libavformat public API header.
static double c[64]
int den
Denominator.
Definition: rational.h:60
static int microdvd_read_close(AVFormatContext *s)
Definition: microdvddec.c:172
int len
void * priv_data
Format private data.
Definition: avformat.h:1355
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:3967
static int get_duration(const char *buf)
Definition: microdvddec.c:68
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:662
AVCodecParameters * codecpar
Definition: avformat.h:1230
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:328
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
static int microdvd_probe(AVProbeData *p)
Definition: microdvddec.c:39
This structure stores compressed data.
Definition: avcodec.h:1567
AVRational frame_rate
Definition: microdvddec.c:35
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
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:242