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movtextenc.c
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1 /*
2  * 3GPP TS 26.245 Timed Text encoder
3  * Copyright (c) 2012 Philip Langdale <philipl@overt.org>
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 <stdarg.h>
23 #include "avcodec.h"
24 #include "libavutil/avassert.h"
25 #include "libavutil/avstring.h"
26 #include "libavutil/intreadwrite.h"
27 #include "libavutil/mem.h"
28 #include "libavutil/common.h"
29 #include "ass_split.h"
30 #include "ass.h"
31 
32 #define STYLE_FLAG_BOLD (1<<0)
33 #define STYLE_FLAG_ITALIC (1<<1)
34 #define STYLE_FLAG_UNDERLINE (1<<2)
35 #define STYLE_RECORD_SIZE 12
36 #define SIZE_ADD 10
37 
38 #define STYL_BOX (1<<0)
39 #define HLIT_BOX (1<<1)
40 #define HCLR_BOX (1<<2)
41 
42 #define av_bprint_append_any(buf, data, size) av_bprint_append_data(buf, ((const char*)data), size)
43 
44 typedef struct {
45  uint16_t style_start;
46  uint16_t style_end;
47  uint8_t style_flag;
48 } StyleBox;
49 
50 typedef struct {
51  uint16_t start;
52  uint16_t end;
53 } HighlightBox;
54 
55 typedef struct {
56  uint32_t color;
58 
59 typedef struct {
61  AVBPrint buffer;
66  int count;
67  uint8_t box_flags;
68  uint16_t style_entries;
69  uint16_t style_fontID;
71  uint32_t style_color;
72  uint16_t text_pos;
74 
75 typedef struct {
76  uint32_t type;
77  void (*encode)(MovTextContext *s, uint32_t tsmb_type);
78 } Box;
79 
81 {
82  int j;
83  if (s->box_flags & STYL_BOX) {
84  for (j = 0; j < s->count; j++) {
85  av_freep(&s->style_attributes[j]);
86  }
88  }
89 }
90 
91 static void encode_styl(MovTextContext *s, uint32_t tsmb_type)
92 {
93  int j;
94  uint32_t tsmb_size;
95  if (s->box_flags & STYL_BOX) {
96  tsmb_size = s->count * STYLE_RECORD_SIZE + SIZE_ADD;
97  tsmb_size = AV_RB32(&tsmb_size);
98  s->style_entries = AV_RB16(&s->count);
99  s->style_fontID = 0x00 | 0x01<<8;
100  s->style_fontsize = 0x12;
101  s->style_color = MKTAG(0xFF, 0xFF, 0xFF, 0xFF);
102  /*The above three attributes are hard coded for now
103  but will come from ASS style in the future*/
104  av_bprint_append_any(&s->buffer, &tsmb_size, 4);
105  av_bprint_append_any(&s->buffer, &tsmb_type, 4);
107  for (j = 0; j < s->count; j++) {
114  }
115  mov_text_cleanup(s);
116  }
117 }
118 
119 static void encode_hlit(MovTextContext *s, uint32_t tsmb_type)
120 {
121  uint32_t tsmb_size;
122  if (s->box_flags & HLIT_BOX) {
123  tsmb_size = 12;
124  tsmb_size = AV_RB32(&tsmb_size);
125  av_bprint_append_any(&s->buffer, &tsmb_size, 4);
126  av_bprint_append_any(&s->buffer, &tsmb_type, 4);
127  av_bprint_append_any(&s->buffer, &s->hlit.start, 2);
128  av_bprint_append_any(&s->buffer, &s->hlit.end, 2);
129  }
130 }
131 
132 static void encode_hclr(MovTextContext *s, uint32_t tsmb_type)
133 {
134  uint32_t tsmb_size;
135  if (s->box_flags & HCLR_BOX) {
136  tsmb_size = 12;
137  tsmb_size = AV_RB32(&tsmb_size);
138  av_bprint_append_any(&s->buffer, &tsmb_size, 4);
139  av_bprint_append_any(&s->buffer, &tsmb_type, 4);
140  av_bprint_append_any(&s->buffer, &s->hclr.color, 4);
141  }
142 }
143 
144 static const Box box_types[] = {
145  { MKTAG('s','t','y','l'), encode_styl },
146  { MKTAG('h','l','i','t'), encode_hlit },
147  { MKTAG('h','c','l','r'), encode_hclr },
148 };
149 
150 const static size_t box_count = FF_ARRAY_ELEMS(box_types);
151 
153 {
154  /*
155  * For now, we'll use a fixed default style. When we add styling
156  * support, this will be generated from the ASS style.
157  */
158  static const uint8_t text_sample_entry[] = {
159  0x00, 0x00, 0x00, 0x00, // uint32_t displayFlags
160  0x01, // int8_t horizontal-justification
161  0xFF, // int8_t vertical-justification
162  0x00, 0x00, 0x00, 0x00, // uint8_t background-color-rgba[4]
163  // BoxRecord {
164  0x00, 0x00, // int16_t top
165  0x00, 0x00, // int16_t left
166  0x00, 0x00, // int16_t bottom
167  0x00, 0x00, // int16_t right
168  // };
169  // StyleRecord {
170  0x00, 0x00, // uint16_t startChar
171  0x00, 0x00, // uint16_t endChar
172  0x00, 0x01, // uint16_t font-ID
173  0x00, // uint8_t face-style-flags
174  0x12, // uint8_t font-size
175  0xFF, 0xFF, 0xFF, 0xFF, // uint8_t text-color-rgba[4]
176  // };
177  // FontTableBox {
178  0x00, 0x00, 0x00, 0x12, // uint32_t size
179  'f', 't', 'a', 'b', // uint8_t name[4]
180  0x00, 0x01, // uint16_t entry-count
181  // FontRecord {
182  0x00, 0x01, // uint16_t font-ID
183  0x05, // uint8_t font-name-length
184  'S', 'e', 'r', 'i', 'f',// uint8_t font[font-name-length]
185  // };
186  // };
187  };
188 
189  MovTextContext *s = avctx->priv_data;
190 
191  avctx->extradata_size = sizeof text_sample_entry;
193  if (!avctx->extradata)
194  return AVERROR(ENOMEM);
195 
197 
198  memcpy(avctx->extradata, text_sample_entry, avctx->extradata_size);
199 
200  s->ass_ctx = ff_ass_split(avctx->subtitle_header);
201  return s->ass_ctx ? 0 : AVERROR_INVALIDDATA;
202 }
203 
204 static void mov_text_style_cb(void *priv, const char style, int close)
205 {
206  MovTextContext *s = priv;
207  if (!close) {
208  if (!(s->box_flags & STYL_BOX)) { //first style entry
209 
211 
212  if (!s->style_attributes_temp) {
213  av_bprint_clear(&s->buffer);
214  s->box_flags &= ~STYL_BOX;
215  return;
216  }
217 
220  } else {
221  if (s->style_attributes_temp->style_flag) { //break the style record here and start a new one
225  if (!s->style_attributes_temp) {
226  mov_text_cleanup(s);
227  av_bprint_clear(&s->buffer);
228  s->box_flags &= ~STYL_BOX;
229  return;
230  }
231 
234  } else {
237  }
238  }
239  switch (style){
240  case 'b':
242  break;
243  case 'i':
245  break;
246  case 'u':
248  break;
249  }
250  } else {
253 
255 
256  if (!s->style_attributes_temp) {
257  mov_text_cleanup(s);
258  av_bprint_clear(&s->buffer);
259  s->box_flags &= ~STYL_BOX;
260  return;
261  }
262 
264  switch (style){
265  case 'b':
267  break;
268  case 'i':
270  break;
271  case 'u':
273  break;
274  }
275  if (s->style_attributes_temp->style_flag) { //start of new style record
277  }
278  }
279  s->box_flags |= STYL_BOX;
280 }
281 
282 static void mov_text_color_cb(void *priv, unsigned int color, unsigned int color_id)
283 {
284  MovTextContext *s = priv;
285  if (color_id == 2) { //secondary color changes
286  if (s->box_flags & HLIT_BOX) { //close tag
287  s->hlit.end = AV_RB16(&s->text_pos);
288  } else {
289  s->box_flags |= HCLR_BOX;
290  s->box_flags |= HLIT_BOX;
291  s->hlit.start = AV_RB16(&s->text_pos);
292  s->hclr.color = color | (0xFF << 24); //set alpha value to FF
293  }
294  }
295  /* If there are more than one secondary color changes in ASS, take start of
296  first section and end of last section. Movtext allows only one
297  highlight box per sample.
298  */
299 }
300 
301 static void mov_text_text_cb(void *priv, const char *text, int len)
302 {
303  MovTextContext *s = priv;
304  av_bprint_append_data(&s->buffer, text, len);
305  s->text_pos += len;
306 }
307 
308 static void mov_text_new_line_cb(void *priv, int forced)
309 {
310  MovTextContext *s = priv;
311  av_bprint_append_data(&s->buffer, "\n", 1);
312  s->text_pos += 1;
313 }
314 
317  .new_line = mov_text_new_line_cb,
318  .style = mov_text_style_cb,
319  .color = mov_text_color_cb,
320 };
321 
322 static int mov_text_encode_frame(AVCodecContext *avctx, unsigned char *buf,
323  int bufsize, const AVSubtitle *sub)
324 {
325  MovTextContext *s = avctx->priv_data;
326  ASSDialog *dialog;
327  int i, length;
328  size_t j;
329 
330  s->text_pos = 0;
331  s->count = 0;
332  s->box_flags = 0;
333  s->style_entries = 0;
334  for (i = 0; i < sub->num_rects; i++) {
335  const char *ass = sub->rects[i]->ass;
336 
337  if (sub->rects[i]->type != SUBTITLE_ASS) {
338  av_log(avctx, AV_LOG_ERROR, "Only SUBTITLE_ASS type supported.\n");
339  return AVERROR(ENOSYS);
340  }
341 
342 #if FF_API_ASS_TIMING
343  if (!strncmp(ass, "Dialogue: ", 10)) {
344  int num;
345  dialog = ff_ass_split_dialog(s->ass_ctx, ass, 0, &num);
346  for (; dialog && num--; dialog++) {
347  ff_ass_split_override_codes(&mov_text_callbacks, s, dialog->text);
348  }
349  } else {
350 #endif
351  dialog = ff_ass_split_dialog2(s->ass_ctx, ass);
352  if (!dialog)
353  return AVERROR(ENOMEM);
354  ff_ass_split_override_codes(&mov_text_callbacks, s, dialog->text);
355  ff_ass_free_dialog(&dialog);
356 #if FF_API_ASS_TIMING
357  }
358 #endif
359 
360  for (j = 0; j < box_count; j++) {
361  box_types[j].encode(s, box_types[j].type);
362  }
363  }
364 
365  AV_WB16(buf, s->text_pos);
366  buf += 2;
367 
368  if (!av_bprint_is_complete(&s->buffer)) {
369  length = AVERROR(ENOMEM);
370  goto exit;
371  }
372 
373  if (!s->buffer.len) {
374  length = 0;
375  goto exit;
376  }
377 
378  if (s->buffer.len > bufsize - 3) {
379  av_log(avctx, AV_LOG_ERROR, "Buffer too small for ASS event.\n");
380  length = AVERROR(EINVAL);
381  goto exit;
382  }
383 
384  memcpy(buf, s->buffer.str, s->buffer.len);
385  length = s->buffer.len + 2;
386 
387 exit:
388  av_bprint_clear(&s->buffer);
389  return length;
390 }
391 
393 {
394  MovTextContext *s = avctx->priv_data;
397  return 0;
398 }
399 
401  .name = "mov_text",
402  .long_name = NULL_IF_CONFIG_SMALL("3GPP Timed Text subtitle"),
403  .type = AVMEDIA_TYPE_SUBTITLE,
404  .id = AV_CODEC_ID_MOV_TEXT,
405  .priv_data_size = sizeof(MovTextContext),
407  .encode_sub = mov_text_encode_frame,
408  .close = mov_text_encode_close,
409 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
fields extracted from the [Events] section
Definition: ass_split.h:71
Memory handling functions.
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
ASSDialog * ff_ass_split_dialog2(ASSSplitContext *ctx, const char *buf)
Split one ASS Dialogue line from a string buffer.
Definition: ass_split.c:442
static const size_t box_count
Definition: movtextenc.c:150
ASSSplitContext * ff_ass_split(const char *buf)
Split a full ASS file or a ASS header from a string buffer and store the split structure in a newly a...
Definition: ass_split.c:374
static av_cold int mov_text_encode_init(AVCodecContext *avctx)
Definition: movtextenc.c:152
unsigned num_rects
Definition: avcodec.h:3949
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:252
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_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:87
AVCodec.
Definition: avcodec.h:3589
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
Definition: bprint.c:235
uint16_t style_entries
Definition: movtextdec.c:98
AVSubtitleRect ** rects
Definition: avcodec.h:3950
char * text
actual text which will be displayed as a subtitle, can include style override control codes (see ff_a...
Definition: ass_split.h:82
uint8_t style_fontsize
Definition: movtextenc.c:70
This struct can be casted to ASS to access to the split data.
Definition: ass_split.c:197
uint8_t
#define av_cold
Definition: attributes.h:82
#define av_malloc(s)
void ff_ass_free_dialog(ASSDialog **dialogp)
Free a dialogue obtained from ff_ass_split_dialog2().
Definition: ass_split.c:430
ASSSplitContext * ass_ctx
Definition: movtextenc.c:60
AVBPrint buffer
Definition: movtextenc.c:61
#define STYL_BOX
Definition: movtextenc.c:38
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1790
int ff_ass_split_override_codes(const ASSCodesCallbacks *callbacks, void *priv, const char *buf)
Split override codes out of a ASS "Dialogue" Text field.
Definition: ass_split.c:492
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_RB32
Definition: bytestream.h:87
static void mov_text_color_cb(void *priv, unsigned int color, unsigned int color_id)
Definition: movtextenc.c:282
void av_bprint_append_data(AVBPrint *buf, const char *data, unsigned size)
Append data to a print buffer.
Definition: bprint.c:158
uint16_t style_fontID
Definition: movtextenc.c:69
static void mov_text_text_cb(void *priv, const char *text, int len)
Definition: movtextenc.c:301
#define AV_WB16(p, v)
Definition: intreadwrite.h:405
HighlightBox hlit
Definition: movtextenc.c:64
ASSDialog * ff_ass_split_dialog(ASSSplitContext *ctx, const char *buf, int cache, int *number)
Split one or several ASS "Dialogue" lines from a string buffer and store them in an already initializ...
Definition: ass_split.c:411
#define av_log(a,...)
uint16_t end
Definition: movtextenc.c:52
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define STYLE_FLAG_UNDERLINE
Definition: movtextenc.c:34
#define AV_BPRINT_SIZE_UNLIMITED
uint8_t style_flag
Definition: movtextdec.c:70
#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
simple assert() macros that are a bit more flexible than ISO C assert().
GLsizei GLsizei * length
Definition: opengl_enc.c:115
const char * name
Name of the codec implementation.
Definition: avcodec.h:3596
uint32_t color
Definition: movtextenc.c:56
#define STYLE_FLAG_ITALIC
Definition: movtextenc.c:33
static const Box box_types[]
Definition: movtextenc.c:144
static void mov_text_cleanup(MovTextContext *s)
Definition: movtextenc.c:80
uint8_t box_flags
Definition: movtextdec.c:97
void(* text)(void *priv, const char *text, int len)
Definition: ass_split.h:159
typedef void(APIENTRY *FF_PFNGLACTIVETEXTUREPROC)(GLenum texture)
#define SIZE_ADD
Definition: movtextenc.c:36
void(* encode)(MovTextContext *s, uint32_t tsmb_type)
Definition: movtextenc.c:77
#define HLIT_BOX
Definition: movtextenc.c:39
static int av_bprint_is_complete(const AVBPrint *buf)
Test if the print buffer is complete (not truncated).
Definition: bprint.h:185
Set of callback functions corresponding to each override codes that can be encountered in a "Dialogue...
Definition: ass_split.h:154
AVCodec ff_movtext_encoder
Definition: movtextenc.c:400
StyleBox * style_attributes_temp
Definition: movtextenc.c:63
uint16_t style_start
Definition: movtextdec.c:68
#define FF_ARRAY_ELEMS(a)
static int mov_text_encode_frame(AVCodecContext *avctx, unsigned char *buf, int bufsize, const AVSubtitle *sub)
Definition: movtextenc.c:322
Libavcodec external API header.
static const ASSCodesCallbacks mov_text_callbacks
Definition: movtextenc.c:315
static void encode_hclr(MovTextContext *s, uint32_t tsmb_type)
Definition: movtextenc.c:132
uint16_t style_end
Definition: movtextdec.c:69
#define STYLE_RECORD_SIZE
Definition: movtextenc.c:35
main external API structure.
Definition: avcodec.h:1675
static int mov_text_encode_close(AVCodecContext *avctx)
Definition: movtextenc.c:392
#define STYLE_FLAG_BOLD
Definition: movtextenc.c:32
void * buf
Definition: avisynth_c.h:690
GLint GLenum type
Definition: opengl_enc.c:105
int extradata_size
Definition: avcodec.h:1791
uint16_t text_pos
Definition: movtextenc.c:72
uint32_t style_color
Definition: movtextenc.c:71
HilightcolorBox hclr
Definition: movtextenc.c:65
StyleBox ** style_attributes
Definition: movtextenc.c:62
void av_bprint_clear(AVBPrint *buf)
Reset the string to "" but keep internal allocated data.
Definition: bprint.c:227
static void encode_hlit(MovTextContext *s, uint32_t tsmb_type)
Definition: movtextenc.c:119
common internal and external API header
uint16_t start
Definition: movtextenc.c:51
static void mov_text_new_line_cb(void *priv, int forced)
Definition: movtextenc.c:308
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:733
static void mov_text_style_cb(void *priv, const char style, int close)
Definition: movtextenc.c:204
void * priv_data
Definition: avcodec.h:1717
Formatted text, the ass field must be set by the decoder and is authoritative.
Definition: avcodec.h:3905
void av_dynarray_add(void *tab_ptr, int *nb_ptr, void *elem)
Add the pointer to an element to a dynamic array.
Definition: mem.c:324
int len
#define HCLR_BOX
Definition: movtextenc.c:40
#define av_bprint_append_any(buf, data, size)
Definition: movtextenc.c:42
char * ass
0 terminated ASS/SSA compatible event line.
Definition: avcodec.h:3940
void ff_ass_split_free(ASSSplitContext *ctx)
Free all the memory allocated for an ASSSplitContext.
Definition: ass_split.c:479
#define av_freep(p)
enum AVSubtitleType type
Definition: avcodec.h:3931
#define MKTAG(a, b, c, d)
Definition: common.h:342
static void encode_styl(MovTextContext *s, uint32_t tsmb_type)
Definition: movtextenc.c:91
uint8_t * subtitle_header
Header containing style information for text subtitles.
Definition: avcodec.h:3310