FFmpeg
assenc.c
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1 /*
2  * SSA/ASS muxer
3  * Copyright (c) 2008 Michael Niedermayer
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/avstring.h"
23 #include "avformat.h"
24 #include "avio_internal.h"
25 #include "internal.h"
26 #include "mux.h"
27 
28 #include "libavutil/opt.h"
29 
30 typedef struct DialogueLine {
31  int readorder;
32  char *line;
33  struct DialogueLine *prev, *next;
34 } DialogueLine;
35 
36 typedef struct ASSContext {
37  const AVClass *class;
42  int ssa_mode;
44  uint8_t *trailer;
45  size_t trailer_size;
46 } ASSContext;
47 
49 {
50  ASSContext *ass = s->priv_data;
51  AVCodecParameters *par = s->streams[0]->codecpar;
52 
53  avpriv_set_pts_info(s->streams[0], 64, 1, 100);
54  if (par->extradata_size > 0) {
55  size_t header_size = par->extradata_size;
56  uint8_t *trailer = strstr(par->extradata, "\n[Events]");
57 
58  if (trailer)
59  trailer = strstr(trailer, "Format:");
60  if (trailer)
61  trailer = strstr(trailer, "\n");
62 
63  if (trailer) {
64  header_size = (++trailer - par->extradata);
65  ass->trailer_size = par->extradata_size - header_size;
66  if (ass->trailer_size)
67  ass->trailer = trailer;
68  }
69 
70  ffio_write_lines(s->pb, par->extradata, header_size, NULL);
71 
72  ass->ssa_mode = !strstr(par->extradata, "\n[V4+ Styles]");
73  if (!strstr(par->extradata, "\n[Events]"))
74  avio_printf(s->pb, "[Events]\nFormat: %s, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text\n",
75  ass->ssa_mode ? "Marked" : "Layer");
76  }
77 
78  return 0;
79 }
80 
81 static void purge_dialogues(AVFormatContext *s, int force)
82 {
83  int n = 0;
84  ASSContext *ass = s->priv_data;
85  DialogueLine *dialogue = ass->dialogue_cache;
86 
87  while (dialogue && (dialogue->readorder == ass->expected_readorder || force)) {
88  DialogueLine *next = dialogue->next;
89  if (dialogue->readorder != ass->expected_readorder) {
90  av_log(s, AV_LOG_WARNING, "ReadOrder gap found between %d and %d\n",
91  ass->expected_readorder, dialogue->readorder);
92  ass->expected_readorder = dialogue->readorder;
93  }
94  avio_print(s->pb, "Dialogue: ", dialogue->line, "\n");
95  if (dialogue == ass->last_added_dialogue)
96  ass->last_added_dialogue = next;
97  av_freep(&dialogue->line);
98  av_free(dialogue);
99  if (next)
100  next->prev = NULL;
101  dialogue = ass->dialogue_cache = next;
102  ass->expected_readorder++;
103  n++;
104  }
105  ass->cache_size -= n;
106  if (n > 1)
107  av_log(s, AV_LOG_DEBUG, "wrote %d ASS lines, cached dialogues: %d, waiting for event id %d\n",
108  n, ass->cache_size, ass->expected_readorder);
109 }
110 
111 static void insert_dialogue(ASSContext *ass, DialogueLine *dialogue)
112 {
113  DialogueLine *cur, *next = NULL, *prev = NULL;
114 
115  /* from the last added to the end of the list */
116  if (ass->last_added_dialogue) {
117  for (cur = ass->last_added_dialogue; cur; cur = cur->next) {
118  if (cur->readorder > dialogue->readorder)
119  break;
120  prev = cur;
121  next = cur->next;
122  }
123  }
124 
125  /* from the beginning to the last one added */
126  if (!prev) {
127  next = ass->dialogue_cache;
128  for (cur = next; cur != ass->last_added_dialogue; cur = cur->next) {
129  if (cur->readorder > dialogue->readorder)
130  break;
131  prev = cur;
132  next = cur->next;
133  }
134  }
135 
136  if (prev) {
137  prev->next = dialogue;
138  dialogue->prev = prev;
139  } else {
140  dialogue->prev = ass->dialogue_cache;
141  ass->dialogue_cache = dialogue;
142  }
143  if (next) {
144  next->prev = dialogue;
145  dialogue->next = next;
146  }
147  ass->cache_size++;
148  ass->last_added_dialogue = dialogue;
149 }
150 
152 {
153  ASSContext *ass = s->priv_data;
154 
155  long int layer;
156  int text_len;
157  char *p = pkt->data;
158  int64_t start = pkt->pts;
159  int64_t end = start + pkt->duration;
160  int hh1, mm1, ss1, ms1;
161  int hh2, mm2, ss2, ms2;
162  DialogueLine *dialogue = av_mallocz(sizeof(*dialogue));
163 
164  if (!dialogue)
165  return AVERROR(ENOMEM);
166 
167  dialogue->readorder = strtol(p, &p, 10);
168  if (dialogue->readorder < ass->expected_readorder)
169  av_log(s, AV_LOG_WARNING, "Unexpected ReadOrder %d\n",
170  dialogue->readorder);
171  if (*p == ',')
172  p++;
173 
174  if (ass->ssa_mode && !strncmp(p, "Marked=", 7))
175  p += 7;
176 
177  layer = strtol(p, &p, 10);
178  if (*p == ',')
179  p++;
180  hh1 = (int)(start / 360000); mm1 = (int)(start / 6000) % 60;
181  hh2 = (int)(end / 360000); mm2 = (int)(end / 6000) % 60;
182  ss1 = (int)(start / 100) % 60; ms1 = (int)(start % 100);
183  ss2 = (int)(end / 100) % 60; ms2 = (int)(end % 100);
184  if (hh1 > 9) hh1 = 9, mm1 = 59, ss1 = 59, ms1 = 99;
185  if (hh2 > 9) hh2 = 9, mm2 = 59, ss2 = 59, ms2 = 99;
186 
187  text_len = strlen(p);
188  while (text_len > 0 && p[text_len - 1] == '\r' || p[text_len - 1] == '\n')
189  text_len--;
190 
191  dialogue->line = av_asprintf("%s%ld,%d:%02d:%02d.%02d,%d:%02d:%02d.%02d,%.*s",
192  ass->ssa_mode ? "Marked=" : "",
193  layer, hh1, mm1, ss1, ms1, hh2, mm2, ss2, ms2, text_len, p);
194  if (!dialogue->line) {
195  av_free(dialogue);
196  return AVERROR(ENOMEM);
197  }
198  insert_dialogue(ass, dialogue);
200 
201  return 0;
202 }
203 
205 {
206  ASSContext *ass = s->priv_data;
207 
208  purge_dialogues(s, 1);
209 
210  if (ass->trailer) {
211  ffio_write_lines(s->pb, ass->trailer, ass->trailer_size, NULL);
212  }
213 
214  return 0;
215 }
216 
217 #define OFFSET(x) offsetof(ASSContext, x)
218 #define E AV_OPT_FLAG_ENCODING_PARAM
219 static const AVOption options[] = {
220  { "ignore_readorder", "write events immediately, even if they're out-of-order", OFFSET(ignore_readorder), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, E },
221  { NULL },
222 };
223 
224 static const AVClass ass_class = {
225  .class_name = "ass muxer",
226  .item_name = av_default_item_name,
227  .option = options,
228  .version = LIBAVUTIL_VERSION_INT,
229 };
230 
232  .p.name = "ass",
233  .p.long_name = NULL_IF_CONFIG_SMALL("SSA (SubStation Alpha) subtitle"),
234  .p.mime_type = "text/x-ass",
235  .p.extensions = "ass,ssa",
236  .p.audio_codec = AV_CODEC_ID_NONE,
237  .p.video_codec = AV_CODEC_ID_NONE,
238  .p.subtitle_codec = AV_CODEC_ID_ASS,
240  .flags_internal = FF_OFMT_FLAG_MAX_ONE_OF_EACH |
242  .p.priv_class = &ass_class,
243  .priv_data_size = sizeof(ASSContext),
247 };
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:69
AVOutputFormat::name
const char * name
Definition: avformat.h:510
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
opt.h
ASSContext::cache_size
int cache_size
Definition: assenc.c:41
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:47
AVFMT_NOTIMESTAMPS
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:479
int64_t
long long int64_t
Definition: coverity.c:34
av_asprintf
char * av_asprintf(const char *fmt,...)
Definition: avstring.c:115
insert_dialogue
static void insert_dialogue(ASSContext *ass, DialogueLine *dialogue)
Definition: assenc.c:111
AVPacket::data
uint8_t * data
Definition: packet.h:522
AVOption
AVOption.
Definition: opt.h:346
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:540
DialogueLine::readorder
int readorder
Definition: assenc.c:31
FF_OFMT_FLAG_ONLY_DEFAULT_CODECS
#define FF_OFMT_FLAG_ONLY_DEFAULT_CODECS
If this flag is set, then the only permitted audio/video/subtitle codec ids are AVOutputFormat....
Definition: mux.h:59
ASSContext::trailer_size
size_t trailer_size
Definition: assenc.c:45
ASSContext::ignore_readorder
int ignore_readorder
Definition: assenc.c:43
FFOutputFormat::p
AVOutputFormat p
The public AVOutputFormat.
Definition: mux.h:65
AV_CODEC_ID_ASS
@ AV_CODEC_ID_ASS
Definition: codec_id.h:571
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:853
DialogueLine::line
char * line
Definition: assenc.c:32
ASSContext::trailer
uint8_t * trailer
Definition: assenc.c:44
purge_dialogues
static void purge_dialogues(AVFormatContext *s, int force)
Definition: assenc.c:81
pkt
AVPacket * pkt
Definition: movenc.c:59
s
#define s(width, name)
Definition: cbs_vp9.c:198
DialogueLine
Definition: assenc.c:30
write_header
static int write_header(AVFormatContext *s)
Definition: assenc.c:48
AV_LOG_DEBUG
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:201
AVFormatContext
Format I/O context.
Definition: avformat.h:1255
DialogueLine::prev
struct DialogueLine * prev
Definition: assenc.c:33
internal.h
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
ass_class
static const AVClass ass_class
Definition: assenc.c:224
avio_print
#define avio_print(s,...)
Write strings (const char *) to the context.
Definition: avio.h:537
ASSContext::ssa_mode
int ssa_mode
Definition: assenc.c:42
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
FFOutputFormat
Definition: mux.h:61
OFFSET
#define OFFSET(x)
Definition: assenc.c:217
ff_ass_muxer
const FFOutputFormat ff_ass_muxer
Definition: assenc.c:231
DialogueLine::next
struct DialogueLine * next
Definition: assenc.c:33
AVCodecParameters::extradata_size
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:73
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:106
ASSContext::expected_readorder
int expected_readorder
Definition: assenc.c:38
write_packet
static int write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: assenc.c:151
AVFMT_GLOBALHEADER
#define AVFMT_GLOBALHEADER
Format wants global header.
Definition: avformat.h:478
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:50
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:515
avio_internal.h
FF_OFMT_FLAG_MAX_ONE_OF_EACH
#define FF_OFMT_FLAG_MAX_ONE_OF_EACH
If this flag is set, it indicates that for each codec type whose corresponding default codec (i....
Definition: mux.h:50
av_mallocz
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:254
AVFMT_TS_NONSTRICT
#define AVFMT_TS_NONSTRICT
Format does not require strictly increasing timestamps, but they must still be monotonic.
Definition: avformat.h:491
AVClass::class_name
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:71
avformat.h
ffio_write_lines
void ffio_write_lines(AVIOContext *s, const unsigned char *buf, int size, const unsigned char *ending)
Write a sequence of text lines, converting line endings.
Definition: aviobuf.c:959
avio_printf
int avio_printf(AVIOContext *s, const char *fmt,...) av_printf_format(2
Writes a formatted string to the context.
E
#define E
Definition: assenc.c:218
ASSContext
Definition: assdec.c:31
av_free
#define av_free(p)
Definition: tableprint_vlc.h:33
AVPacket
This structure stores compressed data.
Definition: packet.h:499
AV_OPT_TYPE_BOOL
@ AV_OPT_TYPE_BOOL
Definition: opt.h:251
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
ASSContext::last_added_dialogue
DialogueLine * last_added_dialogue
Definition: assenc.c:40
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
avstring.h
options
static const AVOption options[]
Definition: assenc.c:219
int
int
Definition: ffmpeg_filter.c:409
ASSContext::dialogue_cache
DialogueLine * dialogue_cache
Definition: assenc.c:39
write_trailer
static int write_trailer(AVFormatContext *s)
Definition: assenc.c:204
mux.h