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ass_split.c
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1 /*
2  * SSA/ASS spliting functions
3  * Copyright (c) 2010 Aurelien Jacobs <aurel@gnuage.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 "avcodec.h"
23 #include "ass_split.h"
24 
25 typedef enum {
26  ASS_STR,
27  ASS_INT,
28  ASS_FLT,
29  ASS_COLOR,
30  ASS_TIMESTAMP,
31  ASS_ALGN,
32 } ASSFieldType;
33 
34 typedef struct {
35  const char *name;
36  int type;
37  int offset;
38 } ASSFields;
39 
40 typedef struct {
41  const char *section;
42  const char *format_header;
43  const char *fields_header;
44  int size;
45  int offset;
46  int offset_count;
47  ASSFields fields[24];
48 } ASSSection;
49 
50 static const ASSSection ass_sections[] = {
51  { .section = "Script Info",
52  .offset = offsetof(ASS, script_info),
53  .fields = {{"ScriptType", ASS_STR, offsetof(ASSScriptInfo, script_type)},
54  {"Collisions", ASS_STR, offsetof(ASSScriptInfo, collisions) },
55  {"PlayResX", ASS_INT, offsetof(ASSScriptInfo, play_res_x) },
56  {"PlayResY", ASS_INT, offsetof(ASSScriptInfo, play_res_y) },
57  {"Timer", ASS_FLT, offsetof(ASSScriptInfo, timer) },
58  {0},
59  }
60  },
61  { .section = "V4+ Styles",
62  .format_header = "Format",
63  .fields_header = "Style",
64  .size = sizeof(ASSStyle),
65  .offset = offsetof(ASS, styles),
66  .offset_count = offsetof(ASS, styles_count),
67  .fields = {{"Name", ASS_STR, offsetof(ASSStyle, name) },
68  {"Fontname", ASS_STR, offsetof(ASSStyle, font_name) },
69  {"Fontsize", ASS_INT, offsetof(ASSStyle, font_size) },
70  {"PrimaryColour", ASS_COLOR, offsetof(ASSStyle, primary_color) },
71  {"SecondaryColour", ASS_COLOR, offsetof(ASSStyle, secondary_color)},
72  {"OutlineColour", ASS_COLOR, offsetof(ASSStyle, outline_color) },
73  {"BackColour", ASS_COLOR, offsetof(ASSStyle, back_color) },
74  {"Bold", ASS_INT, offsetof(ASSStyle, bold) },
75  {"Italic", ASS_INT, offsetof(ASSStyle, italic) },
76  {"Underline", ASS_INT, offsetof(ASSStyle, underline) },
77  {"StrikeOut", ASS_INT, offsetof(ASSStyle, strikeout) },
78  {"ScaleX", ASS_FLT, offsetof(ASSStyle, scalex) },
79  {"ScaleY", ASS_FLT, offsetof(ASSStyle, scaley) },
80  {"Spacing", ASS_FLT, offsetof(ASSStyle, spacing) },
81  {"Angle", ASS_FLT, offsetof(ASSStyle, angle) },
82  {"BorderStyle", ASS_INT, offsetof(ASSStyle, border_style) },
83  {"Outline", ASS_FLT, offsetof(ASSStyle, outline) },
84  {"Shadow", ASS_FLT, offsetof(ASSStyle, shadow) },
85  {"Alignment", ASS_INT, offsetof(ASSStyle, alignment) },
86  {"MarginL", ASS_INT, offsetof(ASSStyle, margin_l) },
87  {"MarginR", ASS_INT, offsetof(ASSStyle, margin_r) },
88  {"MarginV", ASS_INT, offsetof(ASSStyle, margin_v) },
89  {"Encoding", ASS_INT, offsetof(ASSStyle, encoding) },
90  {0},
91  }
92  },
93  { .section = "V4 Styles",
94  .format_header = "Format",
95  .fields_header = "Style",
96  .size = sizeof(ASSStyle),
97  .offset = offsetof(ASS, styles),
98  .offset_count = offsetof(ASS, styles_count),
99  .fields = {{"Name", ASS_STR, offsetof(ASSStyle, name) },
100  {"Fontname", ASS_STR, offsetof(ASSStyle, font_name) },
101  {"Fontsize", ASS_INT, offsetof(ASSStyle, font_size) },
102  {"PrimaryColour", ASS_COLOR, offsetof(ASSStyle, primary_color) },
103  {"SecondaryColour", ASS_COLOR, offsetof(ASSStyle, secondary_color)},
104  {"TertiaryColour", ASS_COLOR, offsetof(ASSStyle, outline_color) },
105  {"BackColour", ASS_COLOR, offsetof(ASSStyle, back_color) },
106  {"Bold", ASS_INT, offsetof(ASSStyle, bold) },
107  {"Italic", ASS_INT, offsetof(ASSStyle, italic) },
108  {"BorderStyle", ASS_INT, offsetof(ASSStyle, border_style) },
109  {"Outline", ASS_FLT, offsetof(ASSStyle, outline) },
110  {"Shadow", ASS_FLT, offsetof(ASSStyle, shadow) },
111  {"Alignment", ASS_ALGN, offsetof(ASSStyle, alignment) },
112  {"MarginL", ASS_INT, offsetof(ASSStyle, margin_l) },
113  {"MarginR", ASS_INT, offsetof(ASSStyle, margin_r) },
114  {"MarginV", ASS_INT, offsetof(ASSStyle, margin_v) },
115  {"AlphaLevel", ASS_INT, offsetof(ASSStyle, alpha_level) },
116  {"Encoding", ASS_INT, offsetof(ASSStyle, encoding) },
117  {0},
118  }
119  },
120  { .section = "Events",
121  .format_header = "Format",
122  .fields_header = "Dialogue",
123  .size = sizeof(ASSDialog),
124  .offset = offsetof(ASS, dialogs),
125  .offset_count = offsetof(ASS, dialogs_count),
126  .fields = {{"Layer", ASS_INT, offsetof(ASSDialog, layer) },
127  {"Start", ASS_TIMESTAMP, offsetof(ASSDialog, start) },
128  {"End", ASS_TIMESTAMP, offsetof(ASSDialog, end) },
129  {"Style", ASS_STR, offsetof(ASSDialog, style) },
130  {"Name", ASS_STR, offsetof(ASSDialog, name) },
131  {"MarginL", ASS_INT, offsetof(ASSDialog, margin_l)},
132  {"MarginR", ASS_INT, offsetof(ASSDialog, margin_r)},
133  {"MarginV", ASS_INT, offsetof(ASSDialog, margin_v)},
134  {"Effect", ASS_STR, offsetof(ASSDialog, effect) },
135  {"Text", ASS_STR, offsetof(ASSDialog, text) },
136  {0},
137  }
138  },
139 };
140 
141 
142 typedef int (*ASSConvertFunc)(void *dest, const char *buf, int len);
143 
144 static int convert_str(void *dest, const char *buf, int len)
145 {
146  char *str = av_malloc(len + 1);
147  if (str) {
148  memcpy(str, buf, len);
149  str[len] = 0;
150  if (*(void **)dest)
151  av_free(*(void **)dest);
152  *(char **)dest = str;
153  }
154  return !str;
155 }
156 static int convert_int(void *dest, const char *buf, int len)
157 {
158  return sscanf(buf, "%d", (int *)dest) == 1;
159 }
160 static int convert_flt(void *dest, const char *buf, int len)
161 {
162  return sscanf(buf, "%f", (float *)dest) == 1;
163 }
164 static int convert_color(void *dest, const char *buf, int len)
165 {
166  return sscanf(buf, "&H%8x", (int *)dest) == 1 ||
167  sscanf(buf, "%d", (int *)dest) == 1;
168 }
169 static int convert_timestamp(void *dest, const char *buf, int len)
170 {
171  int c, h, m, s, cs;
172  if ((c = sscanf(buf, "%d:%02d:%02d.%02d", &h, &m, &s, &cs)) == 4)
173  *(int *)dest = 360000*h + 6000*m + 100*s + cs;
174  return c == 4;
175 }
176 static int convert_alignment(void *dest, const char *buf, int len)
177 {
178  int a;
179  if (sscanf(buf, "%d", &a) == 1) {
180  /* convert V4 Style alignment to V4+ Style */
181  *(int *)dest = a + ((a&4) >> 1) - 5*!!(a&8);
182  return 1;
183  }
184  return 0;
185 }
186 
187 static const ASSConvertFunc convert_func[] = {
188  [ASS_STR] = convert_str,
189  [ASS_INT] = convert_int,
190  [ASS_FLT] = convert_flt,
191  [ASS_COLOR] = convert_color,
192  [ASS_TIMESTAMP] = convert_timestamp,
193  [ASS_ALGN] = convert_alignment,
194 };
195 
196 
197 struct ASSSplitContext {
198  ASS ass;
199  int current_section;
200  int field_number[FF_ARRAY_ELEMS(ass_sections)];
201  int *field_order[FF_ARRAY_ELEMS(ass_sections)];
202 };
203 
204 
205 static uint8_t *realloc_section_array(ASSSplitContext *ctx)
206 {
207  const ASSSection *section = &ass_sections[ctx->current_section];
208  int *count = (int *)((uint8_t *)&ctx->ass + section->offset_count);
209  void **section_ptr = (void **)((uint8_t *)&ctx->ass + section->offset);
210  uint8_t *tmp = av_realloc_array(*section_ptr, (*count+1), section->size);
211  if (!tmp)
212  return NULL;
213  *section_ptr = tmp;
214  tmp += *count * section->size;
215  memset(tmp, 0, section->size);
216  (*count)++;
217  return tmp;
218 }
219 
220 static inline int is_eol(char buf)
221 {
222  return buf == '\r' || buf == '\n' || buf == 0;
223 }
224 
225 static inline const char *skip_space(const char *buf)
226 {
227  while (*buf == ' ')
228  buf++;
229  return buf;
230 }
231 
232 static int *get_default_field_orders(const ASSSection *section)
233 {
234  int i;
235  int *order = av_malloc_array(FF_ARRAY_ELEMS(section->fields), sizeof(*order));
236 
237  if (!order)
238  return NULL;
239  for (i = 0; section->fields[i].name; i++)
240  order[i] = i;
241  while (i < FF_ARRAY_ELEMS(section->fields))
242  order[i] = -1;
243  return order;
244 }
245 
246 static const char *ass_split_section(ASSSplitContext *ctx, const char *buf)
247 {
248  const ASSSection *section = &ass_sections[ctx->current_section];
249  int *number = &ctx->field_number[ctx->current_section];
250  int *order = ctx->field_order[ctx->current_section];
251  int *tmp, i, len;
252 
253  while (buf && *buf) {
254  if (buf[0] == '[') {
255  ctx->current_section = -1;
256  break;
257  }
258  if (buf[0] == ';' || (buf[0] == '!' && buf[1] == ':')) {
259  /* skip comments */
260  } else if (section->format_header && !order) {
261  len = strlen(section->format_header);
262  if (strncmp(buf, section->format_header, len) || buf[len] != ':')
263  goto next_line;
264  buf += len + 1;
265  while (!is_eol(*buf)) {
266  buf = skip_space(buf);
267  len = strcspn(buf, ", \r\n");
268  if (!(tmp = av_realloc_array(order, (*number + 1), sizeof(*order))))
269  return NULL;
270  order = tmp;
271  order[*number] = -1;
272  for (i=0; section->fields[i].name; i++)
273  if (!strncmp(buf, section->fields[i].name, len)) {
274  order[*number] = i;
275  break;
276  }
277  (*number)++;
278  buf = skip_space(buf + len + (buf[len] == ','));
279  }
280  ctx->field_order[ctx->current_section] = order;
281  } else if (section->fields_header) {
282  len = strlen(section->fields_header);
283  if (!strncmp(buf, section->fields_header, len) && buf[len] == ':') {
284  uint8_t *ptr, *struct_ptr = realloc_section_array(ctx);
285  if (!struct_ptr) return NULL;
286 
287  /* No format header line found so far, assume default */
288  if (!order) {
289  order = get_default_field_orders(section);
290  if (!order)
291  return NULL;
292  ctx->field_order[ctx->current_section] = order;
293  }
294 
295  buf += len + 1;
296  for (i=0; !is_eol(*buf) && i < *number; i++) {
297  int last = i == *number - 1;
298  buf = skip_space(buf);
299  len = strcspn(buf, last ? "\r\n" : ",\r\n");
300  if (order[i] >= 0) {
301  ASSFieldType type = section->fields[order[i]].type;
302  ptr = struct_ptr + section->fields[order[i]].offset;
303  convert_func[type](ptr, buf, len);
304  }
305  buf += len;
306  if (!last && *buf) buf++;
307  buf = skip_space(buf);
308  }
309  }
310  } else {
311  len = strcspn(buf, ":\r\n");
312  if (buf[len] == ':') {
313  for (i=0; section->fields[i].name; i++)
314  if (!strncmp(buf, section->fields[i].name, len)) {
315  ASSFieldType type = section->fields[i].type;
316  uint8_t *ptr = (uint8_t *)&ctx->ass + section->offset;
317  ptr += section->fields[i].offset;
318  buf = skip_space(buf + len + 1);
319  convert_func[type](ptr, buf, strcspn(buf, "\r\n"));
320  break;
321  }
322  }
323  }
324 next_line:
325  buf += strcspn(buf, "\n");
326  buf += !!*buf;
327  }
328  return buf;
329 }
330 
331 static int ass_split(ASSSplitContext *ctx, const char *buf)
332 {
333  char c, section[16];
334  int i;
335 
336  if (ctx->current_section >= 0)
337  buf = ass_split_section(ctx, buf);
338 
339  while (buf && *buf) {
340  if (sscanf(buf, "[%15[0-9A-Za-z+ ]]%c", section, &c) == 2) {
341  buf += strcspn(buf, "\n");
342  buf += !!*buf;
343  for (i=0; i<FF_ARRAY_ELEMS(ass_sections); i++)
344  if (!strcmp(section, ass_sections[i].section)) {
345  ctx->current_section = i;
346  buf = ass_split_section(ctx, buf);
347  }
348  } else {
349  buf += strcspn(buf, "\n");
350  buf += !!*buf;
351  }
352  }
353  return buf ? 0 : AVERROR_INVALIDDATA;
354 }
355 
356 ASSSplitContext *ff_ass_split(const char *buf)
357 {
358  ASSSplitContext *ctx = av_mallocz(sizeof(*ctx));
359  ctx->current_section = -1;
360  if (ass_split(ctx, buf) < 0) {
361  ff_ass_split_free(ctx);
362  return NULL;
363  }
364  return ctx;
365 }
366 
367 static void free_section(ASSSplitContext *ctx, const ASSSection *section)
368 {
369  uint8_t *ptr = (uint8_t *)&ctx->ass + section->offset;
370  int i, j, *count, c = 1;
371 
372  if (section->format_header) {
373  ptr = *(void **)ptr;
374  count = (int *)((uint8_t *)&ctx->ass + section->offset_count);
375  } else
376  count = &c;
377 
378  if (ptr)
379  for (i=0; i<*count; i++, ptr += section->size)
380  for (j=0; section->fields[j].name; j++) {
381  const ASSFields *field = &section->fields[j];
382  if (field->type == ASS_STR)
383  av_freep(ptr + field->offset);
384  }
385  *count = 0;
386 
387  if (section->format_header)
388  av_freep((uint8_t *)&ctx->ass + section->offset);
389 }
390 
391 ASSDialog *ff_ass_split_dialog(ASSSplitContext *ctx, const char *buf,
392  int cache, int *number)
393 {
394  ASSDialog *dialog = NULL;
395  int i, count;
396  if (!cache)
397  for (i=0; i<FF_ARRAY_ELEMS(ass_sections); i++)
398  if (!strcmp(ass_sections[i].section, "Events")) {
399  free_section(ctx, &ass_sections[i]);
400  break;
401  }
402  count = ctx->ass.dialogs_count;
403  if (ass_split(ctx, buf) == 0)
404  dialog = ctx->ass.dialogs + count;
405  if (number)
406  *number = ctx->ass.dialogs_count - count;
407  return dialog;
408 }
409 
410 void ff_ass_split_free(ASSSplitContext *ctx)
411 {
412  if (ctx) {
413  int i;
414  for (i=0; i<FF_ARRAY_ELEMS(ass_sections); i++) {
415  free_section(ctx, &ass_sections[i]);
416  av_freep(&(ctx->field_order[i]));
417  }
418  av_free(ctx);
419  }
420 }
421 
422 
423 int ff_ass_split_override_codes(const ASSCodesCallbacks *callbacks, void *priv,
424  const char *buf)
425 {
426  const char *text = NULL;
427  char new_line[2];
428  int text_len = 0;
429 
430  while (buf && *buf) {
431  if (text && callbacks->text &&
432  (sscanf(buf, "\\%1[nN]", new_line) == 1 ||
433  !strncmp(buf, "{\\", 2))) {
434  callbacks->text(priv, text, text_len);
435  text = NULL;
436  }
437  if (sscanf(buf, "\\%1[nN]", new_line) == 1) {
438  if (callbacks->new_line)
439  callbacks->new_line(priv, new_line[0] == 'N');
440  buf += 2;
441  } else if (!strncmp(buf, "{\\", 2)) {
442  buf++;
443  while (*buf == '\\') {
444  char style[2], c[2], sep[2], c_num[2] = "0", tmp[128] = {0};
445  unsigned int color = 0xFFFFFFFF;
446  int len, size = -1, an = -1, alpha = -1;
447  int x1, y1, x2, y2, t1 = -1, t2 = -1;
448  if (sscanf(buf, "\\%1[bisu]%1[01\\}]%n", style, c, &len) > 1) {
449  int close = c[0] == '0' ? 1 : c[0] == '1' ? 0 : -1;
450  len += close != -1;
451  if (callbacks->style)
452  callbacks->style(priv, style[0], close);
453  } else if (sscanf(buf, "\\c%1[\\}]%n", sep, &len) > 0 ||
454  sscanf(buf, "\\c&H%X&%1[\\}]%n", &color, sep, &len) > 1 ||
455  sscanf(buf, "\\%1[1234]c%1[\\}]%n", c_num, sep, &len) > 1 ||
456  sscanf(buf, "\\%1[1234]c&H%X&%1[\\}]%n", c_num, &color, sep, &len) > 2) {
457  if (callbacks->color)
458  callbacks->color(priv, color, c_num[0] - '0');
459  } else if (sscanf(buf, "\\alpha%1[\\}]%n", sep, &len) > 0 ||
460  sscanf(buf, "\\alpha&H%2X&%1[\\}]%n", &alpha, sep, &len) > 1 ||
461  sscanf(buf, "\\%1[1234]a%1[\\}]%n", c_num, sep, &len) > 1 ||
462  sscanf(buf, "\\%1[1234]a&H%2X&%1[\\}]%n", c_num, &alpha, sep, &len) > 2) {
463  if (callbacks->alpha)
464  callbacks->alpha(priv, alpha, c_num[0] - '0');
465  } else if (sscanf(buf, "\\fn%1[\\}]%n", sep, &len) > 0 ||
466  sscanf(buf, "\\fn%127[^\\}]%1[\\}]%n", tmp, sep, &len) > 1) {
467  if (callbacks->font_name)
468  callbacks->font_name(priv, tmp[0] ? tmp : NULL);
469  } else if (sscanf(buf, "\\fs%1[\\}]%n", sep, &len) > 0 ||
470  sscanf(buf, "\\fs%u%1[\\}]%n", &size, sep, &len) > 1) {
471  if (callbacks->font_size)
472  callbacks->font_size(priv, size);
473  } else if (sscanf(buf, "\\a%1[\\}]%n", sep, &len) > 0 ||
474  sscanf(buf, "\\a%2u%1[\\}]%n", &an, sep, &len) > 1 ||
475  sscanf(buf, "\\an%1[\\}]%n", sep, &len) > 0 ||
476  sscanf(buf, "\\an%1u%1[\\}]%n", &an, sep, &len) > 1) {
477  if (an != -1 && buf[2] != 'n')
478  an = (an&3) + (an&4 ? 6 : an&8 ? 3 : 0);
479  if (callbacks->alignment)
480  callbacks->alignment(priv, an);
481  } else if (sscanf(buf, "\\r%1[\\}]%n", sep, &len) > 0 ||
482  sscanf(buf, "\\r%127[^\\}]%1[\\}]%n", tmp, sep, &len) > 1) {
483  if (callbacks->cancel_overrides)
484  callbacks->cancel_overrides(priv, tmp);
485  } else if (sscanf(buf, "\\move(%d,%d,%d,%d)%1[\\}]%n", &x1, &y1, &x2, &y2, sep, &len) > 4 ||
486  sscanf(buf, "\\move(%d,%d,%d,%d,%d,%d)%1[\\}]%n", &x1, &y1, &x2, &y2, &t1, &t2, sep, &len) > 6) {
487  if (callbacks->move)
488  callbacks->move(priv, x1, y1, x2, y2, t1, t2);
489  } else if (sscanf(buf, "\\pos(%d,%d)%1[\\}]%n", &x1, &y1, sep, &len) > 2) {
490  if (callbacks->move)
491  callbacks->move(priv, x1, y1, x1, y1, -1, -1);
492  } else if (sscanf(buf, "\\org(%d,%d)%1[\\}]%n", &x1, &y1, sep, &len) > 2) {
493  if (callbacks->origin)
494  callbacks->origin(priv, x1, y1);
495  } else {
496  len = strcspn(buf+1, "\\}") + 2; /* skip unknown code */
497  }
498  buf += len - 1;
499  }
500  if (*buf++ != '}')
501  return AVERROR_INVALIDDATA;
502  } else {
503  if (!text) {
504  text = buf;
505  text_len = 1;
506  } else
507  text_len++;
508  buf++;
509  }
510  }
511  if (text && callbacks->text)
512  callbacks->text(priv, text, text_len);
513  if (callbacks->end)
514  callbacks->end(priv);
515  return 0;
516 }
517 
518 ASSStyle *ff_ass_style_get(ASSSplitContext *ctx, const char *style)
519 {
520  ASS *ass = &ctx->ass;
521  int i;
522 
523  if (!style || !*style)
524  style = "Default";
525  for (i=0; i<ass->styles_count; i++)
526  if (!strcmp(ass->styles[i].name, style))
527  return ass->styles + i;
528  return NULL;
529 }
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