extern/ffmpeg/libavcodec/dvbsub.c

   1 /*
   2  * DVB subtitle encoding for ffmpeg
   3  * Copyright (c) 2005 Fabrice Bellard.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  18  */
  19 #include "avcodec.h"
  20
  21 typedef struct DVBSubtitleContext {
  22     int hide_state;
  23     int object_version;
  24 } DVBSubtitleContext;
  25
  26 #define PUTBITS2(val)\
  27 {\
  28     bitbuf |= (val) << bitcnt;\
  29     bitcnt -= 2;\
  30     if (bitcnt < 0) {\
  31         bitcnt = 6;\
  32         *q++ = bitbuf;\
  33         bitbuf = 0;\
  34     }\
  35 }
  36
  37 static void dvb_encode_rle2(uint8_t **pq,
  38                             const uint8_t *bitmap, int linesize,
  39                             int w, int h)
  40 {
  41     uint8_t *q;
  42     unsigned int bitbuf;
  43     int bitcnt;
  44     int x, y, len, x1, v, color;
  45
  46     q = *pq;
  47
  48     for(y = 0; y < h; y++) {
  49         *q++ = 0x10;
  50         bitbuf = 0;
  51         bitcnt = 6;
  52
  53         x = 0;
  54         while (x < w) {
  55             x1 = x;
  56             color = bitmap[x1++];
  57             while (x1 < w && bitmap[x1] == color)
  58                 x1++;
  59             len = x1 - x;
  60             if (color == 0 && len == 2) {
  61                 PUTBITS2(0);
  62                 PUTBITS2(0);
  63                 PUTBITS2(1);
  64             } else if (len >= 3 && len <= 10) {
  65                 v = len - 3;
  66                 PUTBITS2(0);
  67                 PUTBITS2((v >> 2) | 2);
  68                 PUTBITS2(v & 3);
  69                 PUTBITS2(color);
  70             } else if (len >= 12 && len <= 27) {
  71                 v = len - 12;
  72                 PUTBITS2(0);
  73                 PUTBITS2(0);
  74                 PUTBITS2(2);
  75                 PUTBITS2(v >> 2);
  76                 PUTBITS2(v & 3);
  77                 PUTBITS2(color);
  78             } else if (len >= 29) {
  79                 /* length = 29 ... 284 */
  80                 if (len > 284)
  81                     len = 284;
  82                 v = len - 29;
  83                 PUTBITS2(0);
  84                 PUTBITS2(0);
  85                 PUTBITS2(3);
  86                 PUTBITS2((v >> 6));
  87                 PUTBITS2((v >> 4) & 3);
  88                 PUTBITS2((v >> 2) & 3);
  89                 PUTBITS2(v & 3);
  90                 PUTBITS2(color);
  91             } else {
  92                 PUTBITS2(color);
  93                 if (color == 0) {
  94                     PUTBITS2(1);
  95                 }
  96                 len = 1;
  97             }
  98             x += len;
  99         }
 100         /* end of line */
 101         PUTBITS2(0);
 102         PUTBITS2(0);
 103         PUTBITS2(0);
 104         if (bitcnt != 6) {
 105             *q++ = bitbuf;
 106         }
 107         *q++ = 0xf0;
 108         bitmap += linesize;
 109     }
 110     *pq = q;
 111 }
 112
 113 #define PUTBITS4(val)\
 114 {\
 115     bitbuf |= (val) << bitcnt;\
 116     bitcnt -= 4;\
 117     if (bitcnt < 0) {\
 118         bitcnt = 4;\
 119         *q++ = bitbuf;\
 120         bitbuf = 0;\
 121     }\
 122 }
 123
 124 /* some DVB decoders only implement 4 bits/pixel */
 125 static void dvb_encode_rle4(uint8_t **pq,
 126                             const uint8_t *bitmap, int linesize,
 127                             int w, int h)
 128 {
 129     uint8_t *q;
 130     unsigned int bitbuf;
 131     int bitcnt;
 132     int x, y, len, x1, v, color;
 133
 134     q = *pq;
 135
 136     for(y = 0; y < h; y++) {
 137         *q++ = 0x11;
 138         bitbuf = 0;
 139         bitcnt = 4;
 140
 141         x = 0;
 142         while (x < w) {
 143             x1 = x;
 144             color = bitmap[x1++];
 145             while (x1 < w && bitmap[x1] == color)
 146                 x1++;
 147             len = x1 - x;
 148             if (color == 0 && len == 2) {
 149                 PUTBITS4(0);
 150                 PUTBITS4(0xd);
 151             } else if (color == 0 && (len >= 3 && len <= 9)) {
 152                 PUTBITS4(0);
 153                 PUTBITS4(len - 2);
 154             } else if (len >= 4 && len <= 7) {
 155                 PUTBITS4(0);
 156                 PUTBITS4(8 + len - 4);
 157                 PUTBITS4(color);
 158             } else if (len >= 9 && len <= 24) {
 159                 PUTBITS4(0);
 160                 PUTBITS4(0xe);
 161                 PUTBITS4(len - 9);
 162                 PUTBITS4(color);
 163             } else if (len >= 25) {
 164                 if (len > 280)
 165                     len = 280;
 166                 v = len - 25;
 167                 PUTBITS4(0);
 168                 PUTBITS4(0xf);
 169                 PUTBITS4(v >> 4);
 170                 PUTBITS4(v & 0xf);
 171                 PUTBITS4(color);
 172             } else {
 173                 PUTBITS4(color);
 174                 if (color == 0) {
 175                     PUTBITS4(0xc);
 176                 }
 177                 len = 1;
 178             }
 179             x += len;
 180         }
 181         /* end of line */
 182         PUTBITS4(0);
 183         PUTBITS4(0);
 184         if (bitcnt != 4) {
 185             *q++ = bitbuf;
 186         }
 187         *q++ = 0xf0;
 188         bitmap += linesize;
 189     }
 190     *pq = q;
 191 }
 192
 193 #define SCALEBITS 10
 194 #define ONE_HALF  (1 << (SCALEBITS - 1))
 195 #define FIX(x)    ((int) ((x) * (1<<SCALEBITS) + 0.5))
 196
 197 #define RGB_TO_Y_CCIR(r, g, b) \
 198 ((FIX(0.29900*219.0/255.0) * (r) + FIX(0.58700*219.0/255.0) * (g) + \
 199   FIX(0.11400*219.0/255.0) * (b) + (ONE_HALF + (16 << SCALEBITS))) >> SCALEBITS)
 200
 201 #define RGB_TO_U_CCIR(r1, g1, b1, shift)\
 202 (((- FIX(0.16874*224.0/255.0) * r1 - FIX(0.33126*224.0/255.0) * g1 +         \
 203      FIX(0.50000*224.0/255.0) * b1 + (ONE_HALF << shift) - 1) >> (SCALEBITS + shift)) + 128)
 204
 205 #define RGB_TO_V_CCIR(r1, g1, b1, shift)\
 206 (((FIX(0.50000*224.0/255.0) * r1 - FIX(0.41869*224.0/255.0) * g1 -           \
 207    FIX(0.08131*224.0/255.0) * b1 + (ONE_HALF << shift) - 1) >> (SCALEBITS + shift)) + 128)
 208
 209 static inline void putbe16(uint8_t **pq, uint16_t v)
 210 {
 211     uint8_t *q;
 212     q = *pq;
 213     *q++ = v >> 8;
 214     *q++ = v;
 215     *pq = q;
 216 }
 217
 218 static int encode_dvb_subtitles(DVBSubtitleContext *s,
 219                                 uint8_t *outbuf, AVSubtitle *h)
 220 {
 221     uint8_t *q, *pseg_len;
 222     int page_id, region_id, clut_id, object_id, i, bpp_index, page_state;
 223
 224
 225     q = outbuf;
 226
 227     page_id = 1;
 228
 229     if (h->num_rects == 0 || h->rects == NULL)
 230         return -1;
 231
 232     *q++ = 0x00; /* subtitle_stream_id */
 233
 234     /* page composition segment */
 235
 236     *q++ = 0x0f; /* sync_byte */
 237     *q++ = 0x10; /* segment_type */
 238     putbe16(&q, page_id);
 239     pseg_len = q;
 240     q += 2; /* segment length */
 241     *q++ = 30; /* page_timeout (seconds) */
 242     if (s->hide_state)
 243         page_state = 0; /* normal case */
 244     else
 245         page_state = 2; /* mode change */
 246     /* page_version = 0 + page_state */
 247     *q++ = s->object_version | (page_state << 2) | 3;
 248
 249     for (region_id = 0; region_id < h->num_rects; region_id++) {
 250         *q++ = region_id;
 251         *q++ = 0xff; /* reserved */
 252         putbe16(&q, h->rects[region_id].x); /* left pos */
 253         putbe16(&q, h->rects[region_id].y); /* top pos */
 254     }
 255
 256     putbe16(&pseg_len, q - pseg_len - 2);
 257
 258     if (!s->hide_state) {
 259         for (clut_id = 0; clut_id < h->num_rects; clut_id++) {
 260
 261             /* CLUT segment */
 262
 263             if (h->rects[clut_id].nb_colors <= 4) {
 264                 /* 2 bpp, some decoders do not support it correctly */
 265                 bpp_index = 0;
 266             } else if (h->rects[clut_id].nb_colors <= 16) {
 267                 /* 4 bpp, standard encoding */
 268                 bpp_index = 1;
 269             } else {
 270                 return -1;
 271             }
 272
 273             *q++ = 0x0f; /* sync byte */
 274             *q++ = 0x12; /* CLUT definition segment */
 275             putbe16(&q, page_id);
 276             pseg_len = q;
 277             q += 2; /* segment length */
 278             *q++ = clut_id;
 279             *q++ = (0 << 4) | 0xf; /* version = 0 */
 280
 281             for(i = 0; i < h->rects[clut_id].nb_colors; i++) {
 282                 *q++ = i; /* clut_entry_id */
 283                 *q++ = (1 << (7 - bpp_index)) | (0xf << 1) | 1; /* 2 bits/pixel full range */
 284                 {
 285                     int a, r, g, b;
 286                     a = (h->rects[clut_id].rgba_palette[i] >> 24) & 0xff;
 287                     r = (h->rects[clut_id].rgba_palette[i] >> 16) & 0xff;
 288                     g = (h->rects[clut_id].rgba_palette[i] >> 8) & 0xff;
 289                     b = (h->rects[clut_id].rgba_palette[i] >> 0) & 0xff;
 290
 291                     *q++ = RGB_TO_Y_CCIR(r, g, b);
 292                     *q++ = RGB_TO_V_CCIR(r, g, b, 0);
 293                     *q++ = RGB_TO_U_CCIR(r, g, b, 0);
 294                     *q++ = 255 - a;
 295                 }
 296             }
 297
 298             putbe16(&pseg_len, q - pseg_len - 2);
 299         }
 300     }
 301
 302     for (region_id = 0; region_id < h->num_rects; region_id++) {
 303
 304         /* region composition segment */
 305
 306         if (h->rects[region_id].nb_colors <= 4) {
 307             /* 2 bpp, some decoders do not support it correctly */
 308             bpp_index = 0;
 309         } else if (h->rects[region_id].nb_colors <= 16) {
 310             /* 4 bpp, standard encoding */
 311             bpp_index = 1;
 312         } else {
 313             return -1;
 314         }
 315
 316         *q++ = 0x0f; /* sync_byte */
 317         *q++ = 0x11; /* segment_type */
 318         putbe16(&q, page_id);
 319         pseg_len = q;
 320         q += 2; /* segment length */
 321         *q++ = region_id;
 322         *q++ = (s->object_version << 4) | (0 << 3) | 0x07; /* version , no fill */
 323         putbe16(&q, h->rects[region_id].w); /* region width */
 324         putbe16(&q, h->rects[region_id].h); /* region height */
 325         *q++ = ((1 + bpp_index) << 5) | ((1 + bpp_index) << 2) | 0x03;
 326         *q++ = region_id; /* clut_id == region_id */
 327         *q++ = 0; /* 8 bit fill colors */
 328         *q++ = 0x03; /* 4 bit and 2 bit fill colors */
 329
 330         if (!s->hide_state) {
 331             putbe16(&q, region_id); /* object_id == region_id */
 332             *q++ = (0 << 6) | (0 << 4);
 333             *q++ = 0;
 334             *q++ = 0xf0;
 335             *q++ = 0;
 336         }
 337
 338         putbe16(&pseg_len, q - pseg_len - 2);
 339     }
 340
 341     if (!s->hide_state) {
 342
 343         for (object_id = 0; object_id < h->num_rects; object_id++) {
 344             /* Object Data segment */
 345
 346             if (h->rects[object_id].nb_colors <= 4) {
 347                 /* 2 bpp, some decoders do not support it correctly */
 348                 bpp_index = 0;
 349             } else if (h->rects[object_id].nb_colors <= 16) {
 350                 /* 4 bpp, standard encoding */
 351                 bpp_index = 1;
 352             } else {
 353                 return -1;
 354             }
 355
 356             *q++ = 0x0f; /* sync byte */
 357             *q++ = 0x13;
 358             putbe16(&q, page_id);
 359             pseg_len = q;
 360             q += 2; /* segment length */
 361
 362             putbe16(&q, object_id);
 363             *q++ = (s->object_version << 4) | (0 << 2) | (0 << 1) | 1; /* version = 0,
 364                                                                        onject_coding_method,
 365                                                                        non_modifying_color_flag */
 366             {
 367                 uint8_t *ptop_field_len, *pbottom_field_len, *top_ptr, *bottom_ptr;
 368                 void (*dvb_encode_rle)(uint8_t **pq,
 369                                         const uint8_t *bitmap, int linesize,
 370                                         int w, int h);
 371                 ptop_field_len = q;
 372                 q += 2;
 373                 pbottom_field_len = q;
 374                 q += 2;
 375
 376                 if (bpp_index == 0)
 377                     dvb_encode_rle = dvb_encode_rle2;
 378                 else
 379                     dvb_encode_rle = dvb_encode_rle4;
 380
 381                 top_ptr = q;
 382                 dvb_encode_rle(&q, h->rects[object_id].bitmap, h->rects[object_id].w * 2,
 383                                     h->rects[object_id].w, h->rects[object_id].h >> 1);
 384                 bottom_ptr = q;
 385                 dvb_encode_rle(&q, h->rects[object_id].bitmap + h->rects[object_id].w,
 386                                     h->rects[object_id].w * 2, h->rects[object_id].w,
 387                                     h->rects[object_id].h >> 1);
 388
 389                 putbe16(&ptop_field_len, bottom_ptr - top_ptr);
 390                 putbe16(&pbottom_field_len, q - bottom_ptr);
 391             }
 392
 393             putbe16(&pseg_len, q - pseg_len - 2);
 394         }
 395     }
 396
 397     /* end of display set segment */
 398
 399     *q++ = 0x0f; /* sync_byte */
 400     *q++ = 0x80; /* segment_type */
 401     putbe16(&q, page_id);
 402     pseg_len = q;
 403     q += 2; /* segment length */
 404
 405     putbe16(&pseg_len, q - pseg_len - 2);
 406
 407     *q++ = 0xff; /* end of PES data */
 408
 409     s->object_version = (s->object_version + 1) & 0xf;
 410     s->hide_state = !s->hide_state;
 411     return q - outbuf;
 412 }
 413
 414 static int dvbsub_init_decoder(AVCodecContext *avctx)
 415 {
 416     return 0;
 417 }
 418
 419 static int dvbsub_close_decoder(AVCodecContext *avctx)
 420 {
 421     return 0;
 422 }
 423
 424 static int dvbsub_encode(AVCodecContext *avctx,
 425                        unsigned char *buf, int buf_size, void *data)
 426 {
 427     DVBSubtitleContext *s = avctx->priv_data;
 428     AVSubtitle *sub = data;
 429     int ret;
 430
 431     ret = encode_dvb_subtitles(s, buf, sub);
 432     return ret;
 433 }
 434
 435 AVCodec dvbsub_encoder = {
 436     "dvbsub",
 437     CODEC_TYPE_SUBTITLE,
 438     CODEC_ID_DVB_SUBTITLE,
 439     sizeof(DVBSubtitleContext),
 440     dvbsub_init_decoder,
 441     dvbsub_encode,
 442     dvbsub_close_decoder,
 443 };