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dvdsubdec.c
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1 /*
2  * DVD subtitle decoding
3  * Copyright (c) 2005 Fabrice Bellard
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 "get_bits.h"
24 #include "internal.h"
25 
26 #include "libavutil/attributes.h"
27 #include "libavutil/colorspace.h"
28 #include "libavutil/opt.h"
29 #include "libavutil/imgutils.h"
30 #include "libavutil/avstring.h"
31 #include "libavutil/bswap.h"
32 
33 typedef struct DVDSubContext
34 {
35  AVClass *class;
36  uint32_t palette[16];
37  char *palette_str;
38  char *ifo_str;
39  int has_palette;
40  uint8_t colormap[4];
41  uint8_t alpha[256];
42  uint8_t buf[0x10000];
43  int buf_size;
44  int forced_subs_only;
45 #ifdef DEBUG
46  int sub_id;
47 #endif
48 } DVDSubContext;
49 
50 static void yuv_a_to_rgba(const uint8_t *ycbcr, const uint8_t *alpha, uint32_t *rgba, int num_values)
51 {
52  const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;
53  uint8_t r, g, b;
54  int i, y, cb, cr;
55  int r_add, g_add, b_add;
56 
57  for (i = num_values; i > 0; i--) {
58  y = *ycbcr++;
59  cr = *ycbcr++;
60  cb = *ycbcr++;
61  YUV_TO_RGB1_CCIR(cb, cr);
62  YUV_TO_RGB2_CCIR(r, g, b, y);
63  *rgba++ = (*alpha++ << 24) | (r << 16) | (g << 8) | b;
64  }
65 }
66 
67 static int decode_run_2bit(GetBitContext *gb, int *color)
68 {
69  unsigned int v, t;
70 
71  v = 0;
72  for (t = 1; v < t && t <= 0x40; t <<= 2)
73  v = (v << 4) | get_bits(gb, 4);
74  *color = v & 3;
75  if (v < 4) { /* Code for fill rest of line */
76  return INT_MAX;
77  }
78  return v >> 2;
79 }
80 
81 static int decode_run_8bit(GetBitContext *gb, int *color)
82 {
83  int len;
84  int has_run = get_bits1(gb);
85  if (get_bits1(gb))
86  *color = get_bits(gb, 8);
87  else
88  *color = get_bits(gb, 2);
89  if (has_run) {
90  if (get_bits1(gb)) {
91  len = get_bits(gb, 7);
92  if (len == 0)
93  len = INT_MAX;
94  else
95  len += 9;
96  } else
97  len = get_bits(gb, 3) + 2;
98  } else
99  len = 1;
100  return len;
101 }
102 
103 static int decode_rle(uint8_t *bitmap, int linesize, int w, int h,
104  const uint8_t *buf, int start, int buf_size, int is_8bit)
105 {
106  GetBitContext gb;
107  int bit_len;
108  int x, y, len, color;
109  uint8_t *d;
110 
111  if (start >= buf_size)
112  return -1;
113 
114  if (w <= 0 || h <= 0)
115  return -1;
116 
117  bit_len = (buf_size - start) * 8;
118  init_get_bits(&gb, buf + start, bit_len);
119 
120  x = 0;
121  y = 0;
122  d = bitmap;
123  for(;;) {
124  if (get_bits_count(&gb) > bit_len)
125  return -1;
126  if (is_8bit)
127  len = decode_run_8bit(&gb, &color);
128  else
129  len = decode_run_2bit(&gb, &color);
130  len = FFMIN(len, w - x);
131  memset(d + x, color, len);
132  x += len;
133  if (x >= w) {
134  y++;
135  if (y >= h)
136  break;
137  d += linesize;
138  x = 0;
139  /* byte align */
140  align_get_bits(&gb);
141  }
142  }
143  return 0;
144 }
145 
146 static void guess_palette(DVDSubContext* ctx,
147  uint32_t *rgba_palette,
148  uint32_t subtitle_color)
149 {
150  static const uint8_t level_map[4][4] = {
151  // this configuration (full range, lowest to highest) in tests
152  // seemed most common, so assume this
153  {0xff},
154  {0x00, 0xff},
155  {0x00, 0x80, 0xff},
156  {0x00, 0x55, 0xaa, 0xff},
157  };
158  uint8_t color_used[16] = { 0 };
159  int nb_opaque_colors, i, level, j, r, g, b;
160  uint8_t *colormap = ctx->colormap, *alpha = ctx->alpha;
161 
162  if(ctx->has_palette) {
163  for(i = 0; i < 4; i++)
164  rgba_palette[i] = (ctx->palette[colormap[i]] & 0x00ffffff)
165  | ((alpha[i] * 17U) << 24);
166  return;
167  }
168 
169  for(i = 0; i < 4; i++)
170  rgba_palette[i] = 0;
171 
172  nb_opaque_colors = 0;
173  for(i = 0; i < 4; i++) {
174  if (alpha[i] != 0 && !color_used[colormap[i]]) {
175  color_used[colormap[i]] = 1;
176  nb_opaque_colors++;
177  }
178  }
179 
180  if (nb_opaque_colors == 0)
181  return;
182 
183  j = 0;
184  memset(color_used, 0, 16);
185  for(i = 0; i < 4; i++) {
186  if (alpha[i] != 0) {
187  if (!color_used[colormap[i]]) {
188  level = level_map[nb_opaque_colors][j];
189  r = (((subtitle_color >> 16) & 0xff) * level) >> 8;
190  g = (((subtitle_color >> 8) & 0xff) * level) >> 8;
191  b = (((subtitle_color >> 0) & 0xff) * level) >> 8;
192  rgba_palette[i] = b | (g << 8) | (r << 16) | ((alpha[i] * 17) << 24);
193  color_used[colormap[i]] = (i + 1);
194  j++;
195  } else {
196  rgba_palette[i] = (rgba_palette[color_used[colormap[i]] - 1] & 0x00ffffff) |
197  ((alpha[i] * 17) << 24);
198  }
199  }
200  }
201 }
202 
203 static void reset_rects(AVSubtitle *sub_header)
204 {
205  int i;
206 
207  if (sub_header->rects) {
208  for (i = 0; i < sub_header->num_rects; i++) {
209  av_freep(&sub_header->rects[i]->pict.data[0]);
210  av_freep(&sub_header->rects[i]->pict.data[1]);
211  av_freep(&sub_header->rects[i]);
212  }
213  av_freep(&sub_header->rects);
214  sub_header->num_rects = 0;
215  }
216 }
217 
218 #define READ_OFFSET(a) (big_offsets ? AV_RB32(a) : AV_RB16(a))
219 
220 static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,
221  const uint8_t *buf, int buf_size)
222 {
223  int cmd_pos, pos, cmd, x1, y1, x2, y2, offset1, offset2, next_cmd_pos;
224  int big_offsets, offset_size, is_8bit = 0;
225  const uint8_t *yuv_palette = NULL;
226  uint8_t *colormap = ctx->colormap, *alpha = ctx->alpha;
227  int date;
228  int i;
229  int is_menu = 0;
230 
231  if (buf_size < 10)
232  return -1;
233 
234  if (AV_RB16(buf) == 0) { /* HD subpicture with 4-byte offsets */
235  big_offsets = 1;
236  offset_size = 4;
237  cmd_pos = 6;
238  } else {
239  big_offsets = 0;
240  offset_size = 2;
241  cmd_pos = 2;
242  }
243 
244  cmd_pos = READ_OFFSET(buf + cmd_pos);
245 
246  if (cmd_pos < 0 || cmd_pos > buf_size - 2 - offset_size)
247  return AVERROR(EAGAIN);
248 
249  while (cmd_pos > 0 && cmd_pos < buf_size - 2 - offset_size) {
250  date = AV_RB16(buf + cmd_pos);
251  next_cmd_pos = READ_OFFSET(buf + cmd_pos + 2);
252  av_dlog(NULL, "cmd_pos=0x%04x next=0x%04x date=%d\n",
253  cmd_pos, next_cmd_pos, date);
254  pos = cmd_pos + 2 + offset_size;
255  offset1 = -1;
256  offset2 = -1;
257  x1 = y1 = x2 = y2 = 0;
258  while (pos < buf_size) {
259  cmd = buf[pos++];
260  av_dlog(NULL, "cmd=%02x\n", cmd);
261  switch(cmd) {
262  case 0x00:
263  /* menu subpicture */
264  is_menu = 1;
265  break;
266  case 0x01:
267  /* set start date */
268  sub_header->start_display_time = (date << 10) / 90;
269  break;
270  case 0x02:
271  /* set end date */
272  sub_header->end_display_time = (date << 10) / 90;
273  break;
274  case 0x03:
275  /* set colormap */
276  if ((buf_size - pos) < 2)
277  goto fail;
278  colormap[3] = buf[pos] >> 4;
279  colormap[2] = buf[pos] & 0x0f;
280  colormap[1] = buf[pos + 1] >> 4;
281  colormap[0] = buf[pos + 1] & 0x0f;
282  pos += 2;
283  break;
284  case 0x04:
285  /* set alpha */
286  if ((buf_size - pos) < 2)
287  goto fail;
288  alpha[3] = buf[pos] >> 4;
289  alpha[2] = buf[pos] & 0x0f;
290  alpha[1] = buf[pos + 1] >> 4;
291  alpha[0] = buf[pos + 1] & 0x0f;
292  pos += 2;
293  av_dlog(NULL, "alpha=%x%x%x%x\n", alpha[0],alpha[1],alpha[2],alpha[3]);
294  break;
295  case 0x05:
296  case 0x85:
297  if ((buf_size - pos) < 6)
298  goto fail;
299  x1 = (buf[pos] << 4) | (buf[pos + 1] >> 4);
300  x2 = ((buf[pos + 1] & 0x0f) << 8) | buf[pos + 2];
301  y1 = (buf[pos + 3] << 4) | (buf[pos + 4] >> 4);
302  y2 = ((buf[pos + 4] & 0x0f) << 8) | buf[pos + 5];
303  if (cmd & 0x80)
304  is_8bit = 1;
305  av_dlog(NULL, "x1=%d x2=%d y1=%d y2=%d\n", x1, x2, y1, y2);
306  pos += 6;
307  break;
308  case 0x06:
309  if ((buf_size - pos) < 4)
310  goto fail;
311  offset1 = AV_RB16(buf + pos);
312  offset2 = AV_RB16(buf + pos + 2);
313  av_dlog(NULL, "offset1=0x%04x offset2=0x%04x\n", offset1, offset2);
314  pos += 4;
315  break;
316  case 0x86:
317  if ((buf_size - pos) < 8)
318  goto fail;
319  offset1 = AV_RB32(buf + pos);
320  offset2 = AV_RB32(buf + pos + 4);
321  av_dlog(NULL, "offset1=0x%04x offset2=0x%04x\n", offset1, offset2);
322  pos += 8;
323  break;
324 
325  case 0x83:
326  /* HD set palette */
327  if ((buf_size - pos) < 768)
328  goto fail;
329  yuv_palette = buf + pos;
330  pos += 768;
331  break;
332  case 0x84:
333  /* HD set contrast (alpha) */
334  if ((buf_size - pos) < 256)
335  goto fail;
336  for (i = 0; i < 256; i++)
337  alpha[i] = 0xFF - buf[pos+i];
338  pos += 256;
339  break;
340 
341  case 0xff:
342  goto the_end;
343  default:
344  av_dlog(NULL, "unrecognised subpicture command 0x%x\n", cmd);
345  goto the_end;
346  }
347  }
348  the_end:
349  if (offset1 >= 0) {
350  int w, h;
351  uint8_t *bitmap;
352 
353  /* decode the bitmap */
354  w = x2 - x1 + 1;
355  if (w < 0)
356  w = 0;
357  h = y2 - y1 + 1;
358  if (h < 0)
359  h = 0;
360  if (w > 0 && h > 0) {
361  reset_rects(sub_header);
362 
363  sub_header->rects = av_mallocz(sizeof(*sub_header->rects));
364  if (!sub_header->rects)
365  goto fail;
366  sub_header->rects[0] = av_mallocz(sizeof(AVSubtitleRect));
367  if (!sub_header->rects[0])
368  goto fail;
369  sub_header->num_rects = 1;
370  bitmap = sub_header->rects[0]->pict.data[0] = av_malloc(w * h);
371  if (!bitmap)
372  goto fail;
373  if (decode_rle(bitmap, w * 2, w, (h + 1) / 2,
374  buf, offset1, buf_size, is_8bit) < 0)
375  goto fail;
376  if (decode_rle(bitmap + w, w * 2, w, h / 2,
377  buf, offset2, buf_size, is_8bit) < 0)
378  goto fail;
379  sub_header->rects[0]->pict.data[1] = av_mallocz(AVPALETTE_SIZE);
380  if (!sub_header->rects[0]->pict.data[1])
381  goto fail;
382  if (is_8bit) {
383  if (!yuv_palette)
384  goto fail;
385  sub_header->rects[0]->nb_colors = 256;
386  yuv_a_to_rgba(yuv_palette, alpha, (uint32_t*)sub_header->rects[0]->pict.data[1], 256);
387  } else {
388  sub_header->rects[0]->nb_colors = 4;
389  guess_palette(ctx, (uint32_t*)sub_header->rects[0]->pict.data[1],
390  0xffff00);
391  }
392  sub_header->rects[0]->x = x1;
393  sub_header->rects[0]->y = y1;
394  sub_header->rects[0]->w = w;
395  sub_header->rects[0]->h = h;
396  sub_header->rects[0]->type = SUBTITLE_BITMAP;
397  sub_header->rects[0]->pict.linesize[0] = w;
398  sub_header->rects[0]->flags = is_menu ? AV_SUBTITLE_FLAG_FORCED : 0;
399  }
400  }
401  if (next_cmd_pos < cmd_pos) {
402  av_log(NULL, AV_LOG_ERROR, "Invalid command offset\n");
403  break;
404  }
405  if (next_cmd_pos == cmd_pos)
406  break;
407  cmd_pos = next_cmd_pos;
408  }
409  if (sub_header->num_rects > 0)
410  return is_menu;
411  fail:
412  reset_rects(sub_header);
413  return -1;
414 }
415 
416 static int is_transp(const uint8_t *buf, int pitch, int n,
417  const uint8_t *transp_color)
418 {
419  int i;
420  for(i = 0; i < n; i++) {
421  if (!transp_color[*buf])
422  return 0;
423  buf += pitch;
424  }
425  return 1;
426 }
427 
428 /* return 0 if empty rectangle, 1 if non empty */
429 static int find_smallest_bounding_rectangle(AVSubtitle *s)
430 {
431  uint8_t transp_color[256] = { 0 };
432  int y1, y2, x1, x2, y, w, h, i;
433  uint8_t *bitmap;
434 
435  if (s->num_rects == 0 || !s->rects || s->rects[0]->w <= 0 || s->rects[0]->h <= 0)
436  return 0;
437 
438  for(i = 0; i < s->rects[0]->nb_colors; i++) {
439  if ((((uint32_t*)s->rects[0]->pict.data[1])[i] >> 24) == 0)
440  transp_color[i] = 1;
441  }
442  y1 = 0;
443  while (y1 < s->rects[0]->h && is_transp(s->rects[0]->pict.data[0] + y1 * s->rects[0]->pict.linesize[0],
444  1, s->rects[0]->w, transp_color))
445  y1++;
446  if (y1 == s->rects[0]->h) {
447  av_freep(&s->rects[0]->pict.data[0]);
448  s->rects[0]->w = s->rects[0]->h = 0;
449  return 0;
450  }
451 
452  y2 = s->rects[0]->h - 1;
453  while (y2 > 0 && is_transp(s->rects[0]->pict.data[0] + y2 * s->rects[0]->pict.linesize[0], 1,
454  s->rects[0]->w, transp_color))
455  y2--;
456  x1 = 0;
457  while (x1 < (s->rects[0]->w - 1) && is_transp(s->rects[0]->pict.data[0] + x1, s->rects[0]->pict.linesize[0],
458  s->rects[0]->h, transp_color))
459  x1++;
460  x2 = s->rects[0]->w - 1;
461  while (x2 > 0 && is_transp(s->rects[0]->pict.data[0] + x2, s->rects[0]->pict.linesize[0], s->rects[0]->h,
462  transp_color))
463  x2--;
464  w = x2 - x1 + 1;
465  h = y2 - y1 + 1;
466  bitmap = av_malloc(w * h);
467  if (!bitmap)
468  return 1;
469  for(y = 0; y < h; y++) {
470  memcpy(bitmap + w * y, s->rects[0]->pict.data[0] + x1 + (y1 + y) * s->rects[0]->pict.linesize[0], w);
471  }
472  av_freep(&s->rects[0]->pict.data[0]);
473  s->rects[0]->pict.data[0] = bitmap;
474  s->rects[0]->pict.linesize[0] = w;
475  s->rects[0]->w = w;
476  s->rects[0]->h = h;
477  s->rects[0]->x += x1;
478  s->rects[0]->y += y1;
479  return 1;
480 }
481 
482 #ifdef DEBUG
483 #define ALPHA_MIX(A,BACK,FORE) (((255-(A)) * (BACK) + (A) * (FORE)) / 255)
484 static void ppm_save(const char *filename, uint8_t *bitmap, int w, int h,
485  uint32_t *rgba_palette)
486 {
487  int x, y, alpha;
488  uint32_t v;
489  int back[3] = {0, 255, 0}; /* green background */
490  FILE *f;
491 
492  f = fopen(filename, "w");
493  if (!f) {
494  perror(filename);
495  return;
496  }
497  fprintf(f, "P6\n"
498  "%d %d\n"
499  "%d\n",
500  w, h, 255);
501  for(y = 0; y < h; y++) {
502  for(x = 0; x < w; x++) {
503  v = rgba_palette[bitmap[y * w + x]];
504  alpha = v >> 24;
505  putc(ALPHA_MIX(alpha, back[0], (v >> 16) & 0xff), f);
506  putc(ALPHA_MIX(alpha, back[1], (v >> 8) & 0xff), f);
507  putc(ALPHA_MIX(alpha, back[2], (v >> 0) & 0xff), f);
508  }
509  }
510  fclose(f);
511 }
512 #endif
513 
514 static int append_to_cached_buf(AVCodecContext *avctx,
515  const uint8_t *buf, int buf_size)
516 {
517  DVDSubContext *ctx = avctx->priv_data;
518 
519  if (ctx->buf_size >= sizeof(ctx->buf) - buf_size) {
520  av_log(avctx, AV_LOG_WARNING, "Attempt to reconstruct "
521  "too large SPU packets aborted.\n");
522  return AVERROR_INVALIDDATA;
523  }
524  memcpy(ctx->buf + ctx->buf_size, buf, buf_size);
525  ctx->buf_size += buf_size;
526  return 0;
527 }
528 
529 static int dvdsub_decode(AVCodecContext *avctx,
530  void *data, int *data_size,
531  AVPacket *avpkt)
532 {
533  DVDSubContext *ctx = avctx->priv_data;
534  const uint8_t *buf = avpkt->data;
535  int buf_size = avpkt->size;
536  AVSubtitle *sub = data;
537  int is_menu;
538 
539  if (ctx->buf_size) {
540  int ret = append_to_cached_buf(avctx, buf, buf_size);
541  if (ret < 0) {
542  *data_size = 0;
543  return ret;
544  }
545  buf = ctx->buf;
546  buf_size = ctx->buf_size;
547  }
548 
549  is_menu = decode_dvd_subtitles(ctx, sub, buf, buf_size);
550  if (is_menu == AVERROR(EAGAIN)) {
551  *data_size = 0;
552  return append_to_cached_buf(avctx, buf, buf_size);
553  }
554 
555  if (is_menu < 0) {
556  no_subtitle:
557  reset_rects(sub);
558  *data_size = 0;
559 
560  return buf_size;
561  }
562  if (!is_menu && find_smallest_bounding_rectangle(sub) == 0)
563  goto no_subtitle;
564 
565  if (ctx->forced_subs_only && !(sub->rects[0]->flags & AV_SUBTITLE_FLAG_FORCED))
566  goto no_subtitle;
567 
568 #if defined(DEBUG)
569  {
570  char ppm_name[32];
571 
572  snprintf(ppm_name, sizeof(ppm_name), "/tmp/%05d.ppm", ctx->sub_id++);
573  av_dlog(NULL, "start=%d ms end =%d ms\n",
574  sub->start_display_time,
575  sub->end_display_time);
576  ppm_save(ppm_name, sub->rects[0]->pict.data[0],
577  sub->rects[0]->w, sub->rects[0]->h, (uint32_t*) sub->rects[0]->pict.data[1]);
578  }
579 #endif
580 
581  ctx->buf_size = 0;
582  *data_size = 1;
583  return buf_size;
584 }
585 
586 static void parse_palette(DVDSubContext *ctx, char *p)
587 {
588  int i;
589 
590  ctx->has_palette = 1;
591  for(i=0;i<16;i++) {
592  ctx->palette[i] = strtoul(p, &p, 16);
593  while(*p == ',' || av_isspace(*p))
594  p++;
595  }
596 }
597 
598 static int parse_ifo_palette(DVDSubContext *ctx, char *p)
599 {
600  FILE *ifo;
601  char ifostr[12];
602  uint32_t sp_pgci, pgci, off_pgc, pgc;
603  uint8_t r, g, b, yuv[65], *buf;
604  int i, y, cb, cr, r_add, g_add, b_add;
605  int ret = 0;
606  const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;
607 
608  ctx->has_palette = 0;
609  if ((ifo = fopen(p, "r")) == NULL) {
610  av_log(ctx, AV_LOG_WARNING, "Unable to open IFO file \"%s\": %s\n", p, av_err2str(AVERROR(errno)));
611  return AVERROR_EOF;
612  }
613  if (fread(ifostr, 12, 1, ifo) != 1 || memcmp(ifostr, "DVDVIDEO-VTS", 12)) {
614  av_log(ctx, AV_LOG_WARNING, "\"%s\" is not a proper IFO file\n", p);
615  ret = AVERROR_INVALIDDATA;
616  goto end;
617  }
618  if (fseek(ifo, 0xCC, SEEK_SET) == -1) {
619  ret = AVERROR(errno);
620  goto end;
621  }
622  if (fread(&sp_pgci, 4, 1, ifo) == 1) {
623  pgci = av_be2ne32(sp_pgci) * 2048;
624  if (fseek(ifo, pgci + 0x0C, SEEK_SET) == -1) {
625  ret = AVERROR(errno);
626  goto end;
627  }
628  if (fread(&off_pgc, 4, 1, ifo) == 1) {
629  pgc = pgci + av_be2ne32(off_pgc);
630  if (fseek(ifo, pgc + 0xA4, SEEK_SET) == -1) {
631  ret = AVERROR(errno);
632  goto end;
633  }
634  if (fread(yuv, 64, 1, ifo) == 1) {
635  buf = yuv;
636  for(i=0; i<16; i++) {
637  y = *++buf;
638  cr = *++buf;
639  cb = *++buf;
640  YUV_TO_RGB1_CCIR(cb, cr);
641  YUV_TO_RGB2_CCIR(r, g, b, y);
642  ctx->palette[i] = (r << 16) + (g << 8) + b;
643  buf++;
644  }
645  ctx->has_palette = 1;
646  }
647  }
648  }
649  if (ctx->has_palette == 0) {
650  av_log(ctx, AV_LOG_WARNING, "Failed to read palette from IFO file \"%s\"\n", p);
651  ret = AVERROR_INVALIDDATA;
652  }
653 end:
654  fclose(ifo);
655  return ret;
656 }
657 
658 static int dvdsub_parse_extradata(AVCodecContext *avctx)
659 {
660  DVDSubContext *ctx = (DVDSubContext*) avctx->priv_data;
661  char *dataorig, *data;
662  int ret = 1;
663 
664  if (!avctx->extradata || !avctx->extradata_size)
665  return 1;
666 
667  dataorig = data = av_malloc(avctx->extradata_size+1);
668  if (!data)
669  return AVERROR(ENOMEM);
670  memcpy(data, avctx->extradata, avctx->extradata_size);
671  data[avctx->extradata_size] = '\0';
672 
673  for(;;) {
674  int pos = strcspn(data, "\n\r");
675  if (pos==0 && *data==0)
676  break;
677 
678  if (strncmp("palette:", data, 8) == 0) {
679  parse_palette(ctx, data + 8);
680  } else if (strncmp("size:", data, 5) == 0) {
681  int w, h;
682  if (sscanf(data + 5, "%dx%d", &w, &h) == 2) {
683  ret = ff_set_dimensions(avctx, w, h);
684  if (ret < 0)
685  goto fail;
686  }
687  }
688 
689  data += pos;
690  data += strspn(data, "\n\r");
691  }
692 
693 fail:
694  av_free(dataorig);
695  return ret;
696 }
697 
698 static av_cold int dvdsub_init(AVCodecContext *avctx)
699 {
700  DVDSubContext *ctx = avctx->priv_data;
701  int ret;
702 
703  if ((ret = dvdsub_parse_extradata(avctx)) < 0)
704  return ret;
705 
706  if (ctx->ifo_str)
707  parse_ifo_palette(ctx, ctx->ifo_str);
708  if (ctx->palette_str)
709  parse_palette(ctx, ctx->palette_str);
710  if (ctx->has_palette) {
711  int i;
712  av_log(avctx, AV_LOG_DEBUG, "palette:");
713  for(i=0;i<16;i++)
714  av_log(avctx, AV_LOG_DEBUG, " 0x%06x", ctx->palette[i]);
715  av_log(avctx, AV_LOG_DEBUG, "\n");
716  }
717 
718  return 1;
719 }
720 
721 static av_cold int dvdsub_close(AVCodecContext *avctx)
722 {
723  DVDSubContext *ctx = avctx->priv_data;
724  ctx->buf_size = 0;
725  return 0;
726 }
727 
728 #define OFFSET(field) offsetof(DVDSubContext, field)
729 #define SD AV_OPT_FLAG_SUBTITLE_PARAM | AV_OPT_FLAG_DECODING_PARAM
730 static const AVOption options[] = {
731  { "palette", "set the global palette", OFFSET(palette_str), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, SD },
732  { "ifo_palette", "obtain the global palette from .IFO file", OFFSET(ifo_str), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, SD },
733  { "forced_subs_only", "Only show forced subtitles", OFFSET(forced_subs_only), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, SD},
734  { NULL }
735 };
736 static const AVClass dvdsub_class = {
737  .class_name = "dvdsubdec",
738  .item_name = av_default_item_name,
739  .option = options,
740  .version = LIBAVUTIL_VERSION_INT,
741 };
742 
743 AVCodec ff_dvdsub_decoder = {
744  .name = "dvdsub",
745  .long_name = NULL_IF_CONFIG_SMALL("DVD subtitles"),
746  .type = AVMEDIA_TYPE_SUBTITLE,
747  .id = AV_CODEC_ID_DVD_SUBTITLE,
748  .priv_data_size = sizeof(DVDSubContext),
749  .init = dvdsub_init,
750  .decode = dvdsub_decode,
751  .close = dvdsub_close,
752  .priv_class = &dvdsub_class,
753 };
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