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 "codec_internal.h"
24 #include "get_bits.h"
25 #include "internal.h"
26 
27 #include "libavutil/attributes.h"
28 #include "libavutil/colorspace.h"
29 #include "libavutil/opt.h"
30 #include "libavutil/imgutils.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   uint8_t  used_color[256];
46 } DVDSubContext;
47 
yuv_a_to_rgba(const uint8_t *ycbcr, const uint8_t *alpha, uint32_t *rgba, int num_values)48 static void yuv_a_to_rgba(const uint8_t *ycbcr, const uint8_t *alpha, uint32_t *rgba, int num_values)
49 {
50     const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;
51     uint8_t r, g, b;
52     int i, y, cb, cr;
53     int r_add, g_add, b_add;
54 
55     for (i = num_values; i > 0; i--) {
56         y = *ycbcr++;
57         cr = *ycbcr++;
58         cb = *ycbcr++;
59         YUV_TO_RGB1_CCIR(cb, cr);
60         YUV_TO_RGB2_CCIR(r, g, b, y);
61         *rgba++ = ((unsigned)*alpha++ << 24) | (r << 16) | (g << 8) | b;
62     }
63 }
64 
decode_run_2bit(GetBitContext *gb, int *color)65 static int decode_run_2bit(GetBitContext *gb, int *color)
66 {
67     unsigned int v, t;
68 
69     v = 0;
70     for (t = 1; v < t && t <= 0x40; t <<= 2)
71         v = (v << 4) | get_bits(gb, 4);
72     *color = v & 3;
73     if (v < 4) { /* Code for fill rest of line */
74         return INT_MAX;
75     }
76     return v >> 2;
77 }
78 
decode_run_8bit(GetBitContext *gb, int *color)79 static int decode_run_8bit(GetBitContext *gb, int *color)
80 {
81     int len;
82     int has_run = get_bits1(gb);
83     *color = get_bits(gb, 2 + 6*get_bits1(gb));
84     if (has_run) {
85         if (get_bits1(gb)) {
86             len = get_bits(gb, 7);
87             if (len == 0)
88                 len = INT_MAX;
89             else
90                 len += 9;
91         } else
92             len = get_bits(gb, 3) + 2;
93     } else
94         len = 1;
95     return len;
96 }
97 
decode_rle(uint8_t *bitmap, int linesize, int w, int h, uint8_t used_color[256], const uint8_t *buf, int start, int buf_size, int is_8bit)98 static int decode_rle(uint8_t *bitmap, int linesize, int w, int h, uint8_t used_color[256],
99                       const uint8_t *buf, int start, int buf_size, int is_8bit)
100 {
101     GetBitContext gb;
102     int bit_len;
103     int x, y, len, color;
104     uint8_t *d;
105 
106     if (start >= buf_size)
107         return -1;
108 
109     if (w <= 0 || h <= 0)
110         return -1;
111 
112     bit_len = (buf_size - start) * 8;
113     init_get_bits(&gb, buf + start, bit_len);
114 
115     x = 0;
116     y = 0;
117     d = bitmap;
118     for(;;) {
119         if (get_bits_count(&gb) > bit_len)
120             return -1;
121         if (is_8bit)
122             len = decode_run_8bit(&gb, &color);
123         else
124             len = decode_run_2bit(&gb, &color);
125         if (len != INT_MAX && len > w - x)
126             return AVERROR_INVALIDDATA;
127         len = FFMIN(len, w - x);
128         memset(d + x, color, len);
129         used_color[color] = 1;
130         x += len;
131         if (x >= w) {
132             y++;
133             if (y >= h)
134                 break;
135             d += linesize;
136             x = 0;
137             /* byte align */
138             align_get_bits(&gb);
139         }
140     }
141     return 0;
142 }
143 
guess_palette(DVDSubContext* ctx, uint32_t *rgba_palette, uint32_t subtitle_color)144 static void guess_palette(DVDSubContext* ctx,
145                           uint32_t *rgba_palette,
146                           uint32_t subtitle_color)
147 {
148     static const uint8_t level_map[4][4] = {
149         // this configuration (full range, lowest to highest) in tests
150         // seemed most common, so assume this
151         {0xff},
152         {0x00, 0xff},
153         {0x00, 0x80, 0xff},
154         {0x00, 0x55, 0xaa, 0xff},
155     };
156     uint8_t color_used[16] = { 0 };
157     int nb_opaque_colors, i, level, j, r, g, b;
158     uint8_t *colormap = ctx->colormap, *alpha = ctx->alpha;
159 
160     if(ctx->has_palette) {
161         for(i = 0; i < 4; i++)
162             rgba_palette[i] = (ctx->palette[colormap[i]] & 0x00ffffff)
163                               | ((alpha[i] * 17U) << 24);
164         return;
165     }
166 
167     for(i = 0; i < 4; i++)
168         rgba_palette[i] = 0;
169 
170     nb_opaque_colors = 0;
171     for(i = 0; i < 4; i++) {
172         if (alpha[i] != 0 && !color_used[colormap[i]]) {
173             color_used[colormap[i]] = 1;
174             nb_opaque_colors++;
175         }
176     }
177 
178     if (nb_opaque_colors == 0)
179         return;
180 
181     j = 0;
182     memset(color_used, 0, 16);
183     for(i = 0; i < 4; i++) {
184         if (alpha[i] != 0) {
185             if (!color_used[colormap[i]])  {
186                 level = level_map[nb_opaque_colors - 1][j];
187                 r = (((subtitle_color >> 16) & 0xff) * level) >> 8;
188                 g = (((subtitle_color >> 8) & 0xff) * level) >> 8;
189                 b = (((subtitle_color >> 0) & 0xff) * level) >> 8;
190                 rgba_palette[i] = b | (g << 8) | (r << 16) | ((alpha[i] * 17U) << 24);
191                 color_used[colormap[i]] = (i + 1);
192                 j++;
193             } else {
194                 rgba_palette[i] = (rgba_palette[color_used[colormap[i]] - 1] & 0x00ffffff) |
195                                     ((alpha[i] * 17U) << 24);
196             }
197         }
198     }
199 }
200 
reset_rects(AVSubtitle *sub_header)201 static void reset_rects(AVSubtitle *sub_header)
202 {
203     int i;
204 
205     if (sub_header->rects) {
206         for (i = 0; i < sub_header->num_rects; i++) {
207             av_freep(&sub_header->rects[i]->data[0]);
208             av_freep(&sub_header->rects[i]->data[1]);
209             av_freep(&sub_header->rects[i]);
210         }
211         av_freep(&sub_header->rects);
212         sub_header->num_rects = 0;
213     }
214 }
215 
216 #define READ_OFFSET(a) (big_offsets ? AV_RB32(a) : AV_RB16(a))
217 
decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header, const uint8_t *buf, int buf_size)218 static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,
219                                 const uint8_t *buf, int buf_size)
220 {
221     int cmd_pos, pos, cmd, x1, y1, x2, y2, next_cmd_pos;
222     int big_offsets, offset_size, is_8bit = 0;
223     const uint8_t *yuv_palette = NULL;
224     uint8_t *colormap = ctx->colormap, *alpha = ctx->alpha;
225     int date;
226     int i;
227     int is_menu = 0;
228     uint32_t size;
229     int64_t offset1, offset2;
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     size = READ_OFFSET(buf + (big_offsets ? 2 : 0));
245     cmd_pos = READ_OFFSET(buf + cmd_pos);
246 
247     if (cmd_pos < 0 || cmd_pos > buf_size - 2 - offset_size) {
248         if (cmd_pos > size) {
249             av_log(ctx, AV_LOG_ERROR, "Discarding invalid packet\n");
250             return 0;
251         }
252         return AVERROR(EAGAIN);
253     }
254 
255     while (cmd_pos > 0 && cmd_pos < buf_size - 2 - offset_size) {
256         date = AV_RB16(buf + cmd_pos);
257         next_cmd_pos = READ_OFFSET(buf + cmd_pos + 2);
258         ff_dlog(NULL, "cmd_pos=0x%04x next=0x%04x date=%d\n",
259                 cmd_pos, next_cmd_pos, date);
260         pos = cmd_pos + 2 + offset_size;
261         offset1 = -1;
262         offset2 = -1;
263         x1 = y1 = x2 = y2 = 0;
264         while (pos < buf_size) {
265             cmd = buf[pos++];
266             ff_dlog(NULL, "cmd=%02x\n", cmd);
267             switch(cmd) {
268             case 0x00:
269                 /* menu subpicture */
270                 is_menu = 1;
271                 break;
272             case 0x01:
273                 /* set start date */
274                 sub_header->start_display_time = (date << 10) / 90;
275                 break;
276             case 0x02:
277                 /* set end date */
278                 sub_header->end_display_time = (date << 10) / 90;
279                 break;
280             case 0x03:
281                 /* set colormap */
282                 if ((buf_size - pos) < 2)
283                     goto fail;
284                 colormap[3] = buf[pos] >> 4;
285                 colormap[2] = buf[pos] & 0x0f;
286                 colormap[1] = buf[pos + 1] >> 4;
287                 colormap[0] = buf[pos + 1] & 0x0f;
288                 pos += 2;
289                 break;
290             case 0x04:
291                 /* set alpha */
292                 if ((buf_size - pos) < 2)
293                     goto fail;
294                 alpha[3] = buf[pos] >> 4;
295                 alpha[2] = buf[pos] & 0x0f;
296                 alpha[1] = buf[pos + 1] >> 4;
297                 alpha[0] = buf[pos + 1] & 0x0f;
298                 pos += 2;
299                 ff_dlog(NULL, "alpha=%x%x%x%x\n", alpha[0],alpha[1],alpha[2],alpha[3]);
300                 break;
301             case 0x05:
302             case 0x85:
303                 if ((buf_size - pos) < 6)
304                     goto fail;
305                 x1 = (buf[pos] << 4) | (buf[pos + 1] >> 4);
306                 x2 = ((buf[pos + 1] & 0x0f) << 8) | buf[pos + 2];
307                 y1 = (buf[pos + 3] << 4) | (buf[pos + 4] >> 4);
308                 y2 = ((buf[pos + 4] & 0x0f) << 8) | buf[pos + 5];
309                 if (cmd & 0x80)
310                     is_8bit = 1;
311                 ff_dlog(NULL, "x1=%d x2=%d y1=%d y2=%d\n", x1, x2, y1, y2);
312                 pos += 6;
313                 break;
314             case 0x06:
315                 if ((buf_size - pos) < 4)
316                     goto fail;
317                 offset1 = AV_RB16(buf + pos);
318                 offset2 = AV_RB16(buf + pos + 2);
319                 ff_dlog(NULL, "offset1=0x%04"PRIx64" offset2=0x%04"PRIx64"\n", offset1, offset2);
320                 pos += 4;
321                 break;
322             case 0x86:
323                 if ((buf_size - pos) < 8)
324                     goto fail;
325                 offset1 = AV_RB32(buf + pos);
326                 offset2 = AV_RB32(buf + pos + 4);
327                 ff_dlog(NULL, "offset1=0x%04"PRIx64" offset2=0x%04"PRIx64"\n", offset1, offset2);
328                 pos += 8;
329                 break;
330 
331             case 0x83:
332                 /* HD set palette */
333                 if ((buf_size - pos) < 768)
334                     goto fail;
335                 yuv_palette = buf + pos;
336                 pos += 768;
337                 break;
338             case 0x84:
339                 /* HD set contrast (alpha) */
340                 if ((buf_size - pos) < 256)
341                     goto fail;
342                 for (i = 0; i < 256; i++)
343                     alpha[i] = 0xFF - buf[pos+i];
344                 pos += 256;
345                 break;
346 
347             case 0xff:
348                 goto the_end;
349             default:
350                 ff_dlog(NULL, "unrecognised subpicture command 0x%x\n", cmd);
351                 goto the_end;
352             }
353         }
354     the_end:
355         if (offset1 >= buf_size || offset2 >= buf_size)
356             goto fail;
357 
358         if (offset1 >= 0 && offset2 >= 0) {
359             int w, h;
360             uint8_t *bitmap;
361 
362             /* decode the bitmap */
363             w = x2 - x1 + 1;
364             if (w < 0)
365                 w = 0;
366             h = y2 - y1 + 1;
367             if (h < 0)
368                 h = 0;
369             if (w > 0 && h > 1) {
370                 reset_rects(sub_header);
371                 memset(ctx->used_color, 0, sizeof(ctx->used_color));
372                 sub_header->rects = av_mallocz(sizeof(*sub_header->rects));
373                 if (!sub_header->rects)
374                     goto fail;
375                 sub_header->rects[0] = av_mallocz(sizeof(AVSubtitleRect));
376                 if (!sub_header->rects[0])
377                     goto fail;
378                 sub_header->num_rects = 1;
379                 bitmap = sub_header->rects[0]->data[0] = av_malloc(w * h);
380                 if (!bitmap)
381                     goto fail;
382                 if (decode_rle(bitmap, w * 2, w, (h + 1) / 2, ctx->used_color,
383                                buf, offset1, buf_size, is_8bit) < 0)
384                     goto fail;
385                 if (decode_rle(bitmap + w, w * 2, w, h / 2, ctx->used_color,
386                                buf, offset2, buf_size, is_8bit) < 0)
387                     goto fail;
388                 sub_header->rects[0]->data[1] = av_mallocz(AVPALETTE_SIZE);
389                 if (!sub_header->rects[0]->data[1])
390                     goto fail;
391                 if (is_8bit) {
392                     if (!yuv_palette)
393                         goto fail;
394                     sub_header->rects[0]->nb_colors = 256;
395                     yuv_a_to_rgba(yuv_palette, alpha,
396                                   (uint32_t *)sub_header->rects[0]->data[1],
397                                   256);
398                 } else {
399                     sub_header->rects[0]->nb_colors = 4;
400                     guess_palette(ctx, (uint32_t*)sub_header->rects[0]->data[1],
401                                   0xffffff);
402                 }
403                 sub_header->rects[0]->x = x1;
404                 sub_header->rects[0]->y = y1;
405                 sub_header->rects[0]->w = w;
406                 sub_header->rects[0]->h = h;
407                 sub_header->rects[0]->type = SUBTITLE_BITMAP;
408                 sub_header->rects[0]->linesize[0] = w;
409                 sub_header->rects[0]->flags = is_menu ? AV_SUBTITLE_FLAG_FORCED : 0;
410             }
411         }
412         if (next_cmd_pos < cmd_pos) {
413             av_log(ctx, AV_LOG_ERROR, "Invalid command offset\n");
414             break;
415         }
416         if (next_cmd_pos == cmd_pos)
417             break;
418         cmd_pos = next_cmd_pos;
419     }
420     if (sub_header->num_rects > 0)
421         return is_menu;
422  fail:
423     reset_rects(sub_header);
424     return -1;
425 }
426 
is_transp(const uint8_t *buf, int pitch, int n, const uint8_t *transp_color)427 static int is_transp(const uint8_t *buf, int pitch, int n,
428                      const uint8_t *transp_color)
429 {
430     int i;
431     for(i = 0; i < n; i++) {
432         if (!transp_color[*buf])
433             return 0;
434         buf += pitch;
435     }
436     return 1;
437 }
438 
439 /* return 0 if empty rectangle, 1 if non empty */
find_smallest_bounding_rectangle(DVDSubContext *ctx, AVSubtitle *s)440 static int find_smallest_bounding_rectangle(DVDSubContext *ctx, AVSubtitle *s)
441 {
442     uint8_t transp_color[256] = { 0 };
443     int y1, y2, x1, x2, y, w, h, i;
444     uint8_t *bitmap;
445     int transparent = 1;
446 
447     if (s->num_rects == 0 || !s->rects || s->rects[0]->w <= 0 || s->rects[0]->h <= 0)
448         return 0;
449 
450     for(i = 0; i < s->rects[0]->nb_colors; i++) {
451         if ((((uint32_t *)s->rects[0]->data[1])[i] >> 24) == 0) {
452             transp_color[i] = 1;
453         } else if (ctx->used_color[i])
454             transparent = 0;
455     }
456     if (transparent)
457         return 0;
458     y1 = 0;
459     while (y1 < s->rects[0]->h && is_transp(s->rects[0]->data[0] + y1 * s->rects[0]->linesize[0],
460                                   1, s->rects[0]->w, transp_color))
461         y1++;
462     if (y1 == s->rects[0]->h) {
463         av_freep(&s->rects[0]->data[0]);
464         s->rects[0]->w = s->rects[0]->h = 0;
465         return 0;
466     }
467 
468     y2 = s->rects[0]->h - 1;
469     while (y2 > 0 && is_transp(s->rects[0]->data[0] + y2 * s->rects[0]->linesize[0], 1,
470                                s->rects[0]->w, transp_color))
471         y2--;
472     x1 = 0;
473     while (x1 < (s->rects[0]->w - 1) && is_transp(s->rects[0]->data[0] + x1, s->rects[0]->linesize[0],
474                                         s->rects[0]->h, transp_color))
475         x1++;
476     x2 = s->rects[0]->w - 1;
477     while (x2 > 0 && is_transp(s->rects[0]->data[0] + x2, s->rects[0]->linesize[0], s->rects[0]->h,
478                                   transp_color))
479         x2--;
480     w = x2 - x1 + 1;
481     h = y2 - y1 + 1;
482     bitmap = av_malloc(w * h);
483     if (!bitmap)
484         return 1;
485     for(y = 0; y < h; y++) {
486         memcpy(bitmap + w * y, s->rects[0]->data[0] + x1 + (y1 + y) * s->rects[0]->linesize[0], w);
487     }
488     av_freep(&s->rects[0]->data[0]);
489     s->rects[0]->data[0] = bitmap;
490     s->rects[0]->linesize[0] = w;
491     s->rects[0]->w = w;
492     s->rects[0]->h = h;
493     s->rects[0]->x += x1;
494     s->rects[0]->y += y1;
495 
496     return 1;
497 }
498 
append_to_cached_buf(AVCodecContext *avctx, const uint8_t *buf, int buf_size)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     av_assert0(buf_size >= 0 && ctx->buf_size <= sizeof(ctx->buf));
505     if (buf_size >= sizeof(ctx->buf) - ctx->buf_size) {
506         av_log(avctx, AV_LOG_WARNING, "Attempt to reconstruct "
507                "too large SPU packets aborted.\n");
508         ctx->buf_size = 0;
509         return AVERROR_INVALIDDATA;
510     }
511     memcpy(ctx->buf + ctx->buf_size, buf, buf_size);
512     ctx->buf_size += buf_size;
513     return 0;
514 }
515 
dvdsub_decode(AVCodecContext *avctx, AVSubtitle *sub, int *data_size, const AVPacket *avpkt)516 static int dvdsub_decode(AVCodecContext *avctx, AVSubtitle *sub,
517                          int *data_size, const AVPacket *avpkt)
518 {
519     DVDSubContext *ctx = avctx->priv_data;
520     const uint8_t *buf = avpkt->data;
521     int buf_size = avpkt->size;
522     int appended = 0;
523     int is_menu;
524 
525     if (ctx->buf_size) {
526         int ret = append_to_cached_buf(avctx, buf, buf_size);
527         if (ret < 0) {
528             *data_size = 0;
529             return ret;
530         }
531         buf = ctx->buf;
532         buf_size = ctx->buf_size;
533         appended = 1;
534     }
535 
536     is_menu = decode_dvd_subtitles(ctx, sub, buf, buf_size);
537     if (is_menu == AVERROR(EAGAIN)) {
538         *data_size = 0;
539         return appended ? 0 : append_to_cached_buf(avctx, buf, buf_size);
540     }
541 
542     if (is_menu < 0) {
543         ctx->buf_size = 0;
544     no_subtitle:
545         reset_rects(sub);
546         *data_size = 0;
547 
548         return buf_size;
549     }
550     if (!is_menu && find_smallest_bounding_rectangle(ctx, sub) == 0)
551         goto no_subtitle;
552 
553     if (ctx->forced_subs_only && !(sub->rects[0]->flags & AV_SUBTITLE_FLAG_FORCED))
554         goto no_subtitle;
555 
556     ctx->buf_size = 0;
557     *data_size = 1;
558     return buf_size;
559 }
560 
parse_ifo_palette(DVDSubContext *ctx, char *p)561 static int parse_ifo_palette(DVDSubContext *ctx, char *p)
562 {
563     FILE *ifo;
564     char ifostr[12];
565     uint32_t sp_pgci, pgci, off_pgc, pgc;
566     uint8_t r, g, b, yuv[65], *buf;
567     int i, y, cb, cr, r_add, g_add, b_add;
568     int ret = 0;
569     const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;
570 
571     ctx->has_palette = 0;
572     if ((ifo = avpriv_fopen_utf8(p, "r")) == NULL) {
573         av_log(ctx, AV_LOG_WARNING, "Unable to open IFO file \"%s\": %s\n", p, av_err2str(AVERROR(errno)));
574         return AVERROR_EOF;
575     }
576     if (fread(ifostr, 12, 1, ifo) != 1 || memcmp(ifostr, "DVDVIDEO-VTS", 12)) {
577         av_log(ctx, AV_LOG_WARNING, "\"%s\" is not a proper IFO file\n", p);
578         ret = AVERROR_INVALIDDATA;
579         goto end;
580     }
581     if (fseek(ifo, 0xCC, SEEK_SET) == -1) {
582         ret = AVERROR(errno);
583         goto end;
584     }
585     if (fread(&sp_pgci, 4, 1, ifo) == 1) {
586         pgci = av_be2ne32(sp_pgci) * 2048;
587         if (fseek(ifo, pgci + 0x0C, SEEK_SET) == -1) {
588             ret = AVERROR(errno);
589             goto end;
590         }
591         if (fread(&off_pgc, 4, 1, ifo) == 1) {
592             pgc = pgci + av_be2ne32(off_pgc);
593             if (fseek(ifo, pgc + 0xA4, SEEK_SET) == -1) {
594                 ret = AVERROR(errno);
595                 goto end;
596             }
597             if (fread(yuv, 64, 1, ifo) == 1) {
598                 buf = yuv;
599                 for(i=0; i<16; i++) {
600                     y  = *++buf;
601                     cr = *++buf;
602                     cb = *++buf;
603                     YUV_TO_RGB1_CCIR(cb, cr);
604                     YUV_TO_RGB2_CCIR(r, g, b, y);
605                     ctx->palette[i] = (r << 16) + (g << 8) + b;
606                     buf++;
607                 }
608                 ctx->has_palette = 1;
609             }
610         }
611     }
612     if (ctx->has_palette == 0) {
613         av_log(ctx, AV_LOG_WARNING, "Failed to read palette from IFO file \"%s\"\n", p);
614         ret = AVERROR_INVALIDDATA;
615     }
616 end:
617     fclose(ifo);
618     return ret;
619 }
620 
dvdsub_parse_extradata(AVCodecContext *avctx)621 static int dvdsub_parse_extradata(AVCodecContext *avctx)
622 {
623     DVDSubContext *ctx = (DVDSubContext*) avctx->priv_data;
624     char *dataorig, *data;
625     int ret = 1;
626 
627     if (!avctx->extradata || !avctx->extradata_size)
628         return 1;
629 
630     dataorig = data = av_malloc(avctx->extradata_size+1);
631     if (!data)
632         return AVERROR(ENOMEM);
633     memcpy(data, avctx->extradata, avctx->extradata_size);
634     data[avctx->extradata_size] = '\0';
635 
636     for(;;) {
637         int pos = strcspn(data, "\n\r");
638         if (pos==0 && *data==0)
639             break;
640 
641         if (strncmp("palette:", data, 8) == 0) {
642             ctx->has_palette = 1;
643             ff_dvdsub_parse_palette(ctx->palette, data + 8);
644         } else if (strncmp("size:", data, 5) == 0) {
645             int w, h;
646             if (sscanf(data + 5, "%dx%d", &w, &h) == 2) {
647                ret = ff_set_dimensions(avctx, w, h);
648                if (ret < 0)
649                    goto fail;
650             }
651         }
652 
653         data += pos;
654         data += strspn(data, "\n\r");
655     }
656 
657 fail:
658     av_free(dataorig);
659     return ret;
660 }
661 
dvdsub_init(AVCodecContext *avctx)662 static av_cold int dvdsub_init(AVCodecContext *avctx)
663 {
664     DVDSubContext *ctx = avctx->priv_data;
665     int ret;
666 
667     if ((ret = dvdsub_parse_extradata(avctx)) < 0)
668         return ret;
669 
670     if (ctx->ifo_str)
671         parse_ifo_palette(ctx, ctx->ifo_str);
672     if (ctx->palette_str) {
673         ctx->has_palette = 1;
674         ff_dvdsub_parse_palette(ctx->palette, ctx->palette_str);
675     }
676     if (ctx->has_palette) {
677         int i;
678         av_log(avctx, AV_LOG_DEBUG, "palette:");
679         for(i=0;i<16;i++)
680             av_log(avctx, AV_LOG_DEBUG, " 0x%06"PRIx32, ctx->palette[i]);
681         av_log(avctx, AV_LOG_DEBUG, "\n");
682     }
683 
684     return 1;
685 }
686 
dvdsub_flush(AVCodecContext *avctx)687 static void dvdsub_flush(AVCodecContext *avctx)
688 {
689     DVDSubContext *ctx = avctx->priv_data;
690     ctx->buf_size = 0;
691 }
692 
693 #define OFFSET(field) offsetof(DVDSubContext, field)
694 #define SD AV_OPT_FLAG_SUBTITLE_PARAM | AV_OPT_FLAG_DECODING_PARAM
695 static const AVOption options[] = {
696     { "palette", "set the global palette", OFFSET(palette_str), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, SD },
697     { "ifo_palette", "obtain the global palette from .IFO file", OFFSET(ifo_str), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, SD },
698     { "forced_subs_only", "Only show forced subtitles", OFFSET(forced_subs_only), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, SD},
699     { NULL }
700 };
701 static const AVClass dvdsub_class = {
702     .class_name = "dvdsubdec",
703     .item_name  = av_default_item_name,
704     .option     = options,
705     .version    = LIBAVUTIL_VERSION_INT,
706 };
707 
708 const FFCodec ff_dvdsub_decoder = {
709     .p.name         = "dvdsub",
710     .p.long_name    = NULL_IF_CONFIG_SMALL("DVD subtitles"),
711     .p.type         = AVMEDIA_TYPE_SUBTITLE,
712     .p.id           = AV_CODEC_ID_DVD_SUBTITLE,
713     .priv_data_size = sizeof(DVDSubContext),
714     .init           = dvdsub_init,
715     FF_CODEC_DECODE_SUB_CB(dvdsub_decode),
716     .flush          = dvdsub_flush,
717     .p.priv_class   = &dvdsub_class,
718     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
719 };
720