FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
dvdsubdec.c
Go to the documentation of this file.
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;
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  bit_len = (buf_size - start) * 8;
112  init_get_bits(&gb, buf + start, bit_len);
113 
114  x = 0;
115  y = 0;
116  d = bitmap;
117  for(;;) {
118  if (get_bits_count(&gb) > bit_len)
119  return -1;
120  if (is_8bit)
121  len = decode_run_8bit(&gb, &color);
122  else
123  len = decode_run_2bit(&gb, &color);
124  len = FFMIN(len, w - x);
125  memset(d + x, color, len);
126  x += len;
127  if (x >= w) {
128  y++;
129  if (y >= h)
130  break;
131  d += linesize;
132  x = 0;
133  /* byte align */
134  align_get_bits(&gb);
135  }
136  }
137  return 0;
138 }
139 
140 static void guess_palette(DVDSubContext* ctx,
141  uint32_t *rgba_palette,
142  uint32_t subtitle_color)
143 {
144  static const uint8_t level_map[4][4] = {
145  // this configuration (full range, lowest to highest) in tests
146  // seemed most common, so assume this
147  {0xff},
148  {0x00, 0xff},
149  {0x00, 0x80, 0xff},
150  {0x00, 0x55, 0xaa, 0xff},
151  };
152  uint8_t color_used[16] = { 0 };
153  int nb_opaque_colors, i, level, j, r, g, b;
154  uint8_t *colormap = ctx->colormap, *alpha = ctx->alpha;
155 
156  if(ctx->has_palette) {
157  for(i = 0; i < 4; i++)
158  rgba_palette[i] = (ctx->palette[colormap[i]] & 0x00ffffff)
159  | ((alpha[i] * 17U) << 24);
160  return;
161  }
162 
163  for(i = 0; i < 4; i++)
164  rgba_palette[i] = 0;
165 
166  nb_opaque_colors = 0;
167  for(i = 0; i < 4; i++) {
168  if (alpha[i] != 0 && !color_used[colormap[i]]) {
169  color_used[colormap[i]] = 1;
170  nb_opaque_colors++;
171  }
172  }
173 
174  if (nb_opaque_colors == 0)
175  return;
176 
177  j = 0;
178  memset(color_used, 0, 16);
179  for(i = 0; i < 4; i++) {
180  if (alpha[i] != 0) {
181  if (!color_used[colormap[i]]) {
182  level = level_map[nb_opaque_colors][j];
183  r = (((subtitle_color >> 16) & 0xff) * level) >> 8;
184  g = (((subtitle_color >> 8) & 0xff) * level) >> 8;
185  b = (((subtitle_color >> 0) & 0xff) * level) >> 8;
186  rgba_palette[i] = b | (g << 8) | (r << 16) | ((alpha[i] * 17) << 24);
187  color_used[colormap[i]] = (i + 1);
188  j++;
189  } else {
190  rgba_palette[i] = (rgba_palette[color_used[colormap[i]] - 1] & 0x00ffffff) |
191  ((alpha[i] * 17) << 24);
192  }
193  }
194  }
195 }
196 
197 static void reset_rects(AVSubtitle *sub_header)
198 {
199  int i;
200 
201  if (sub_header->rects) {
202  for (i = 0; i < sub_header->num_rects; i++) {
203  av_freep(&sub_header->rects[i]->pict.data[0]);
204  av_freep(&sub_header->rects[i]->pict.data[1]);
205  av_freep(&sub_header->rects[i]);
206  }
207  av_freep(&sub_header->rects);
208  sub_header->num_rects = 0;
209  }
210 }
211 
212 #define READ_OFFSET(a) (big_offsets ? AV_RB32(a) : AV_RB16(a))
213 
214 static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,
215  const uint8_t *buf, int buf_size)
216 {
217  int cmd_pos, pos, cmd, x1, y1, x2, y2, offset1, offset2, next_cmd_pos;
218  int big_offsets, offset_size, is_8bit = 0;
219  const uint8_t *yuv_palette = NULL;
220  uint8_t *colormap = ctx->colormap, *alpha = ctx->alpha;
221  int date;
222  int i;
223  int is_menu = 0;
224 
225  if (buf_size < 10)
226  return -1;
227 
228  if (AV_RB16(buf) == 0) { /* HD subpicture with 4-byte offsets */
229  big_offsets = 1;
230  offset_size = 4;
231  cmd_pos = 6;
232  } else {
233  big_offsets = 0;
234  offset_size = 2;
235  cmd_pos = 2;
236  }
237 
238  cmd_pos = READ_OFFSET(buf + cmd_pos);
239 
240  if (cmd_pos < 0 || cmd_pos > buf_size - 2 - offset_size)
241  return AVERROR(EAGAIN);
242 
243  while (cmd_pos > 0 && cmd_pos < buf_size - 2 - offset_size) {
244  date = AV_RB16(buf + cmd_pos);
245  next_cmd_pos = READ_OFFSET(buf + cmd_pos + 2);
246  av_dlog(NULL, "cmd_pos=0x%04x next=0x%04x date=%d\n",
247  cmd_pos, next_cmd_pos, date);
248  pos = cmd_pos + 2 + offset_size;
249  offset1 = -1;
250  offset2 = -1;
251  x1 = y1 = x2 = y2 = 0;
252  while (pos < buf_size) {
253  cmd = buf[pos++];
254  av_dlog(NULL, "cmd=%02x\n", cmd);
255  switch(cmd) {
256  case 0x00:
257  /* menu subpicture */
258  is_menu = 1;
259  break;
260  case 0x01:
261  /* set start date */
262  sub_header->start_display_time = (date << 10) / 90;
263  break;
264  case 0x02:
265  /* set end date */
266  sub_header->end_display_time = (date << 10) / 90;
267  break;
268  case 0x03:
269  /* set colormap */
270  if ((buf_size - pos) < 2)
271  goto fail;
272  colormap[3] = buf[pos] >> 4;
273  colormap[2] = buf[pos] & 0x0f;
274  colormap[1] = buf[pos + 1] >> 4;
275  colormap[0] = buf[pos + 1] & 0x0f;
276  pos += 2;
277  break;
278  case 0x04:
279  /* set alpha */
280  if ((buf_size - pos) < 2)
281  goto fail;
282  alpha[3] = buf[pos] >> 4;
283  alpha[2] = buf[pos] & 0x0f;
284  alpha[1] = buf[pos + 1] >> 4;
285  alpha[0] = buf[pos + 1] & 0x0f;
286  pos += 2;
287  av_dlog(NULL, "alpha=%x%x%x%x\n", alpha[0],alpha[1],alpha[2],alpha[3]);
288  break;
289  case 0x05:
290  case 0x85:
291  if ((buf_size - pos) < 6)
292  goto fail;
293  x1 = (buf[pos] << 4) | (buf[pos + 1] >> 4);
294  x2 = ((buf[pos + 1] & 0x0f) << 8) | buf[pos + 2];
295  y1 = (buf[pos + 3] << 4) | (buf[pos + 4] >> 4);
296  y2 = ((buf[pos + 4] & 0x0f) << 8) | buf[pos + 5];
297  if (cmd & 0x80)
298  is_8bit = 1;
299  av_dlog(NULL, "x1=%d x2=%d y1=%d y2=%d\n", x1, x2, y1, y2);
300  pos += 6;
301  break;
302  case 0x06:
303  if ((buf_size - pos) < 4)
304  goto fail;
305  offset1 = AV_RB16(buf + pos);
306  offset2 = AV_RB16(buf + pos + 2);
307  av_dlog(NULL, "offset1=0x%04x offset2=0x%04x\n", offset1, offset2);
308  pos += 4;
309  break;
310  case 0x86:
311  if ((buf_size - pos) < 8)
312  goto fail;
313  offset1 = AV_RB32(buf + pos);
314  offset2 = AV_RB32(buf + pos + 4);
315  av_dlog(NULL, "offset1=0x%04x offset2=0x%04x\n", offset1, offset2);
316  pos += 8;
317  break;
318 
319  case 0x83:
320  /* HD set palette */
321  if ((buf_size - pos) < 768)
322  goto fail;
323  yuv_palette = buf + pos;
324  pos += 768;
325  break;
326  case 0x84:
327  /* HD set contrast (alpha) */
328  if ((buf_size - pos) < 256)
329  goto fail;
330  for (i = 0; i < 256; i++)
331  alpha[i] = 0xFF - buf[pos+i];
332  pos += 256;
333  break;
334 
335  case 0xff:
336  goto the_end;
337  default:
338  av_dlog(NULL, "unrecognised subpicture command 0x%x\n", cmd);
339  goto the_end;
340  }
341  }
342  the_end:
343  if (offset1 >= 0) {
344  int w, h;
345  uint8_t *bitmap;
346 
347  /* decode the bitmap */
348  w = x2 - x1 + 1;
349  if (w < 0)
350  w = 0;
351  h = y2 - y1 + 1;
352  if (h < 0)
353  h = 0;
354  if (w > 0 && h > 0) {
355  reset_rects(sub_header);
356 
357  bitmap = av_malloc(w * h);
358  sub_header->rects = av_mallocz(sizeof(*sub_header->rects));
359  sub_header->rects[0] = av_mallocz(sizeof(AVSubtitleRect));
360  sub_header->num_rects = 1;
361  sub_header->rects[0]->pict.data[0] = bitmap;
362  decode_rle(bitmap, w * 2, w, (h + 1) / 2,
363  buf, offset1, buf_size, is_8bit);
364  decode_rle(bitmap + w, w * 2, w, h / 2,
365  buf, offset2, buf_size, is_8bit);
366  sub_header->rects[0]->pict.data[1] = av_mallocz(AVPALETTE_SIZE);
367  if (is_8bit) {
368  if (!yuv_palette)
369  goto fail;
370  sub_header->rects[0]->nb_colors = 256;
371  yuv_a_to_rgba(yuv_palette, alpha, (uint32_t*)sub_header->rects[0]->pict.data[1], 256);
372  } else {
373  sub_header->rects[0]->nb_colors = 4;
374  guess_palette(ctx, (uint32_t*)sub_header->rects[0]->pict.data[1],
375  0xffff00);
376  }
377  sub_header->rects[0]->x = x1;
378  sub_header->rects[0]->y = y1;
379  sub_header->rects[0]->w = w;
380  sub_header->rects[0]->h = h;
381  sub_header->rects[0]->type = SUBTITLE_BITMAP;
382  sub_header->rects[0]->pict.linesize[0] = w;
383  sub_header->rects[0]->flags = is_menu ? AV_SUBTITLE_FLAG_FORCED : 0;
384  }
385  }
386  if (next_cmd_pos < cmd_pos) {
387  av_log(NULL, AV_LOG_ERROR, "Invalid command offset\n");
388  break;
389  }
390  if (next_cmd_pos == cmd_pos)
391  break;
392  cmd_pos = next_cmd_pos;
393  }
394  if (sub_header->num_rects > 0)
395  return is_menu;
396  fail:
397  reset_rects(sub_header);
398  return -1;
399 }
400 
401 static int is_transp(const uint8_t *buf, int pitch, int n,
402  const uint8_t *transp_color)
403 {
404  int i;
405  for(i = 0; i < n; i++) {
406  if (!transp_color[*buf])
407  return 0;
408  buf += pitch;
409  }
410  return 1;
411 }
412 
413 /* return 0 if empty rectangle, 1 if non empty */
414 static int find_smallest_bounding_rectangle(AVSubtitle *s)
415 {
416  uint8_t transp_color[256] = { 0 };
417  int y1, y2, x1, x2, y, w, h, i;
418  uint8_t *bitmap;
419 
420  if (s->num_rects == 0 || !s->rects || s->rects[0]->w <= 0 || s->rects[0]->h <= 0)
421  return 0;
422 
423  for(i = 0; i < s->rects[0]->nb_colors; i++) {
424  if ((((uint32_t*)s->rects[0]->pict.data[1])[i] >> 24) == 0)
425  transp_color[i] = 1;
426  }
427  y1 = 0;
428  while (y1 < s->rects[0]->h && is_transp(s->rects[0]->pict.data[0] + y1 * s->rects[0]->pict.linesize[0],
429  1, s->rects[0]->w, transp_color))
430  y1++;
431  if (y1 == s->rects[0]->h) {
432  av_freep(&s->rects[0]->pict.data[0]);
433  s->rects[0]->w = s->rects[0]->h = 0;
434  return 0;
435  }
436 
437  y2 = s->rects[0]->h - 1;
438  while (y2 > 0 && is_transp(s->rects[0]->pict.data[0] + y2 * s->rects[0]->pict.linesize[0], 1,
439  s->rects[0]->w, transp_color))
440  y2--;
441  x1 = 0;
442  while (x1 < (s->rects[0]->w - 1) && is_transp(s->rects[0]->pict.data[0] + x1, s->rects[0]->pict.linesize[0],
443  s->rects[0]->h, transp_color))
444  x1++;
445  x2 = s->rects[0]->w - 1;
446  while (x2 > 0 && is_transp(s->rects[0]->pict.data[0] + x2, s->rects[0]->pict.linesize[0], s->rects[0]->h,
447  transp_color))
448  x2--;
449  w = x2 - x1 + 1;
450  h = y2 - y1 + 1;
451  bitmap = av_malloc(w * h);
452  if (!bitmap)
453  return 1;
454  for(y = 0; y < h; y++) {
455  memcpy(bitmap + w * y, s->rects[0]->pict.data[0] + x1 + (y1 + y) * s->rects[0]->pict.linesize[0], w);
456  }
457  av_freep(&s->rects[0]->pict.data[0]);
458  s->rects[0]->pict.data[0] = bitmap;
459  s->rects[0]->pict.linesize[0] = w;
460  s->rects[0]->w = w;
461  s->rects[0]->h = h;
462  s->rects[0]->x += x1;
463  s->rects[0]->y += y1;
464  return 1;
465 }
466 
467 #ifdef DEBUG
468 #define ALPHA_MIX(A,BACK,FORE) (((255-(A)) * (BACK) + (A) * (FORE)) / 255)
469 static void ppm_save(const char *filename, uint8_t *bitmap, int w, int h,
470  uint32_t *rgba_palette)
471 {
472  int x, y, alpha;
473  uint32_t v;
474  int back[3] = {0, 255, 0}; /* green background */
475  FILE *f;
476 
477  f = fopen(filename, "w");
478  if (!f) {
479  perror(filename);
480  return;
481  }
482  fprintf(f, "P6\n"
483  "%d %d\n"
484  "%d\n",
485  w, h, 255);
486  for(y = 0; y < h; y++) {
487  for(x = 0; x < w; x++) {
488  v = rgba_palette[bitmap[y * w + x]];
489  alpha = v >> 24;
490  putc(ALPHA_MIX(alpha, back[0], (v >> 16) & 0xff), f);
491  putc(ALPHA_MIX(alpha, back[1], (v >> 8) & 0xff), f);
492  putc(ALPHA_MIX(alpha, back[2], (v >> 0) & 0xff), f);
493  }
494  }
495  fclose(f);
496 }
497 #endif
498 
499 static int append_to_cached_buf(AVCodecContext *avctx,
500  const uint8_t *buf, int buf_size)
501 {
502  DVDSubContext *ctx = avctx->priv_data;
503 
504  if (ctx->buf_size > 0xffff - buf_size) {
505  av_log(avctx, AV_LOG_WARNING, "Attempt to reconstruct "
506  "too large SPU packets aborted.\n");
507  av_freep(&ctx->buf);
508  return AVERROR_INVALIDDATA;
509  }
510  ctx->buf = av_realloc(ctx->buf, ctx->buf_size + buf_size);
511  if (!ctx->buf)
512  return AVERROR(ENOMEM);
513  memcpy(ctx->buf + ctx->buf_size, buf, buf_size);
514  ctx->buf_size += buf_size;
515  return 0;
516 }
517 
518 static int dvdsub_decode(AVCodecContext *avctx,
519  void *data, int *data_size,
520  AVPacket *avpkt)
521 {
522  DVDSubContext *ctx = avctx->priv_data;
523  const uint8_t *buf = avpkt->data;
524  int buf_size = avpkt->size;
525  AVSubtitle *sub = data;
526  int is_menu;
527 
528  if (ctx->buf) {
529  int ret = append_to_cached_buf(avctx, buf, buf_size);
530  if (ret < 0) {
531  *data_size = 0;
532  return ret;
533  }
534  buf = ctx->buf;
535  buf_size = ctx->buf_size;
536  }
537 
538  is_menu = decode_dvd_subtitles(ctx, sub, buf, buf_size);
539  if (is_menu == AVERROR(EAGAIN)) {
540  *data_size = 0;
541  return append_to_cached_buf(avctx, buf, buf_size);
542  }
543 
544  if (is_menu < 0) {
545  no_subtitle:
546  reset_rects(sub);
547  *data_size = 0;
548 
549  return buf_size;
550  }
551  if (!is_menu && find_smallest_bounding_rectangle(sub) == 0)
552  goto no_subtitle;
553 
554  if (ctx->forced_subs_only && !(sub->rects[0]->flags & AV_SUBTITLE_FLAG_FORCED))
555  goto no_subtitle;
556 
557 #if defined(DEBUG)
558  {
559  char ppm_name[32];
560 
561  snprintf(ppm_name, sizeof(ppm_name), "/tmp/%05d.ppm", ctx->sub_id++);
562  av_dlog(NULL, "start=%d ms end =%d ms\n",
563  sub->start_display_time,
564  sub->end_display_time);
565  ppm_save(ppm_name, sub->rects[0]->pict.data[0],
566  sub->rects[0]->w, sub->rects[0]->h, (uint32_t*) sub->rects[0]->pict.data[1]);
567  }
568 #endif
569 
570  av_freep(&ctx->buf);
571  ctx->buf_size = 0;
572  *data_size = 1;
573  return buf_size;
574 }
575 
576 static void parse_palette(DVDSubContext *ctx, char *p)
577 {
578  int i;
579 
580  ctx->has_palette = 1;
581  for(i=0;i<16;i++) {
582  ctx->palette[i] = strtoul(p, &p, 16);
583  while(*p == ',' || av_isspace(*p))
584  p++;
585  }
586 }
587 
588 static int parse_ifo_palette(DVDSubContext *ctx, char *p)
589 {
590  FILE *ifo;
591  char ifostr[12];
592  uint32_t sp_pgci, pgci, off_pgc, pgc;
593  uint8_t r, g, b, yuv[65], *buf;
594  int i, y, cb, cr, r_add, g_add, b_add;
595  int ret = 0;
596  const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;
597 
598  ctx->has_palette = 0;
599  if ((ifo = fopen(p, "r")) == NULL) {
600  av_log(ctx, AV_LOG_WARNING, "Unable to open IFO file \"%s\": %s\n", p, strerror(errno));
601  return AVERROR_EOF;
602  }
603  if (fread(ifostr, 12, 1, ifo) != 1 || memcmp(ifostr, "DVDVIDEO-VTS", 12)) {
604  av_log(ctx, AV_LOG_WARNING, "\"%s\" is not a proper IFO file\n", p);
605  ret = AVERROR_INVALIDDATA;
606  goto end;
607  }
608  if (fseek(ifo, 0xCC, SEEK_SET) == -1) {
609  ret = AVERROR(errno);
610  goto end;
611  }
612  if (fread(&sp_pgci, 4, 1, ifo) == 1) {
613  pgci = av_be2ne32(sp_pgci) * 2048;
614  if (fseek(ifo, pgci + 0x0C, SEEK_SET) == -1) {
615  ret = AVERROR(errno);
616  goto end;
617  }
618  if (fread(&off_pgc, 4, 1, ifo) == 1) {
619  pgc = pgci + av_be2ne32(off_pgc);
620  if (fseek(ifo, pgc + 0xA4, SEEK_SET) == -1) {
621  ret = AVERROR(errno);
622  goto end;
623  }
624  if (fread(yuv, 64, 1, ifo) == 1) {
625  buf = yuv;
626  for(i=0; i<16; i++) {
627  y = *++buf;
628  cr = *++buf;
629  cb = *++buf;
630  YUV_TO_RGB1_CCIR(cb, cr);
631  YUV_TO_RGB2_CCIR(r, g, b, y);
632  ctx->palette[i] = (r << 16) + (g << 8) + b;
633  buf++;
634  }
635  ctx->has_palette = 1;
636  }
637  }
638  }
639  if (ctx->has_palette == 0) {
640  av_log(ctx, AV_LOG_WARNING, "Failed to read palette from IFO file \"%s\"\n", p);
641  ret = AVERROR_INVALIDDATA;
642  }
643 end:
644  fclose(ifo);
645  return ret;
646 }
647 
648 static int dvdsub_parse_extradata(AVCodecContext *avctx)
649 {
650  DVDSubContext *ctx = (DVDSubContext*) avctx->priv_data;
651  char *dataorig, *data;
652  int ret = 1;
653 
654  if (!avctx->extradata || !avctx->extradata_size)
655  return 1;
656 
657  dataorig = data = av_malloc(avctx->extradata_size+1);
658  if (!data)
659  return AVERROR(ENOMEM);
660  memcpy(data, avctx->extradata, avctx->extradata_size);
661  data[avctx->extradata_size] = '\0';
662 
663  for(;;) {
664  int pos = strcspn(data, "\n\r");
665  if (pos==0 && *data==0)
666  break;
667 
668  if (strncmp("palette:", data, 8) == 0) {
669  parse_palette(ctx, data + 8);
670  } else if (strncmp("size:", data, 5) == 0) {
671  int w, h;
672  if (sscanf(data + 5, "%dx%d", &w, &h) == 2) {
673  ret = ff_set_dimensions(avctx, w, h);
674  if (ret < 0)
675  goto fail;
676  }
677  }
678 
679  data += pos;
680  data += strspn(data, "\n\r");
681  }
682 
683 fail:
684  av_free(dataorig);
685  return ret;
686 }
687 
688 static av_cold int dvdsub_init(AVCodecContext *avctx)
689 {
690  DVDSubContext *ctx = avctx->priv_data;
691  int ret;
692 
693  if ((ret = dvdsub_parse_extradata(avctx)) < 0)
694  return ret;
695 
696  if (ctx->ifo_str)
697  parse_ifo_palette(ctx, ctx->ifo_str);
698  if (ctx->palette_str)
699  parse_palette(ctx, ctx->palette_str);
700  if (ctx->has_palette) {
701  int i;
702  av_log(avctx, AV_LOG_DEBUG, "palette:");
703  for(i=0;i<16;i++)
704  av_log(avctx, AV_LOG_DEBUG, " 0x%06x", ctx->palette[i]);
705  av_log(avctx, AV_LOG_DEBUG, "\n");
706  }
707 
708  return 1;
709 }
710 
711 static av_cold int dvdsub_close(AVCodecContext *avctx)
712 {
713  DVDSubContext *ctx = avctx->priv_data;
714  av_freep(&ctx->buf);
715  ctx->buf_size = 0;
716  return 0;
717 }
718 
719 #define OFFSET(field) offsetof(DVDSubContext, field)
720 #define SD AV_OPT_FLAG_SUBTITLE_PARAM | AV_OPT_FLAG_DECODING_PARAM
721 static const AVOption options[] = {
722  { "palette", "set the global palette", OFFSET(palette_str), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, SD },
723  { "ifo_palette", "obtain the global palette from .IFO file", OFFSET(ifo_str), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, SD },
724  { "forced_subs_only", "Only show forced subtitles", OFFSET(forced_subs_only), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, SD},
725  { NULL }
726 };
727 static const AVClass dvdsub_class = {
728  .class_name = "dvdsubdec",
729  .item_name = av_default_item_name,
730  .option = options,
731  .version = LIBAVUTIL_VERSION_INT,
732 };
733 
734 AVCodec ff_dvdsub_decoder = {
735  .name = "dvdsub",
736  .long_name = NULL_IF_CONFIG_SMALL("DVD subtitles"),
737  .type = AVMEDIA_TYPE_SUBTITLE,
738  .id = AV_CODEC_ID_DVD_SUBTITLE,
739  .priv_data_size = sizeof(DVDSubContext),
740  .init = dvdsub_init,
741  .decode = dvdsub_decode,
742  .close = dvdsub_close,
743  .priv_class = &dvdsub_class,
744 };
Generated on Fri Dec 5 2014 04:41:53 for FFmpeg by   doxygen 1.8.2