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   1 /*
   2  * MPEG-1/2 decoder
   3  * Copyright (c) 2000, 2001 Fabrice Bellard
   4  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
   5  *
   6  * This file is part of Libav.
   7  *
   8  * Libav is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * Libav is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with Libav; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 /**
  24  * @file
  25  * MPEG-1/2 decoder
  26  */
  27
  28 //#define DEBUG
  29 #include "internal.h"
  30 #include "avcodec.h"
  31 #include "dsputil.h"
  32 #include "mpegvideo.h"
  33
  34 #include "mpeg12.h"
  35 #include "mpeg12data.h"
  36 #include "mpeg12decdata.h"
  37 #include "bytestream.h"
  38 #include "vdpau_internal.h"
  39 #include "xvmc_internal.h"
  40 #include "thread.h"
  41
  42 //#undef NDEBUG
  43 //#include <assert.h>
  44
  45
  46 #define MV_VLC_BITS 9
  47 #define MBINCR_VLC_BITS 9
  48 #define MB_PAT_VLC_BITS 9
  49 #define MB_PTYPE_VLC_BITS 6
  50 #define MB_BTYPE_VLC_BITS 6
  51
  52 static VLC mv_vlc;
  53
  54 /* as H.263, but only 17 codes */
  55 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
  56 {
  57     int code, sign, val, shift;
  58
  59     code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
  60     if (code == 0) {
  61         return pred;
  62     }
  63     if (code < 0) {
  64         return 0xffff;
  65     }
  66
  67     sign  = get_bits1(&s->gb);
  68     shift = fcode - 1;
  69     val   = code;
  70     if (shift) {
  71         val  = (val - 1) << shift;
  72         val |= get_bits(&s->gb, shift);
  73         val++;
  74     }
  75     if (sign)
  76         val = -val;
  77     val += pred;
  78
  79     /* modulo decoding */
  80     return sign_extend(val, 5 + shift);
  81 }
  82
  83 static inline int mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
  84 {
  85     int level, dc, diff, i, j, run;
  86     int component;
  87     RLTable *rl = &ff_rl_mpeg1;
  88     uint8_t * const scantable    = s->intra_scantable.permutated;
  89     const uint16_t *quant_matrix = s->intra_matrix;
  90     const int qscale             = s->qscale;
  91
  92     /* DC coefficient */
  93     component = (n <= 3 ? 0 : n - 4 + 1);
  94     diff = decode_dc(&s->gb, component);
  95     if (diff >= 0xffff)
  96         return -1;
  97     dc  = s->last_dc[component];
  98     dc += diff;
  99     s->last_dc[component] = dc;
 100     block[0] = dc * quant_matrix[0];
 101     av_dlog(s->avctx, "dc=%d diff=%d\n", dc, diff);
 102     i = 0;
 103     {
 104         OPEN_READER(re, &s->gb);
 105         /* now quantify & encode AC coefficients */
 106         for (;;) {
 107             UPDATE_CACHE(re, &s->gb);
 108             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 109
 110             if (level == 127) {
 111                 break;
 112             } else if (level != 0) {
 113                 i += run;
 114                 j = scantable[i];
 115                 level = (level * qscale * quant_matrix[j]) >> 4;
 116                 level = (level - 1) | 1;
 117                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 118                 LAST_SKIP_BITS(re, &s->gb, 1);
 119             } else {
 120                 /* escape */
 121                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
 122                 UPDATE_CACHE(re, &s->gb);
 123                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 124                 if (level == -128) {
 125                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
 126                 } else if (level == 0) {
 127                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
 128                 }
 129                 i += run;
 130                 j = scantable[i];
 131                 if (level < 0) {
 132                     level = -level;
 133                     level = (level * qscale * quant_matrix[j]) >> 4;
 134                     level = (level - 1) | 1;
 135                     level = -level;
 136                 } else {
 137                     level = (level * qscale * quant_matrix[j]) >> 4;
 138                     level = (level - 1) | 1;
 139                 }
 140             }
 141             if (i > 63) {
 142                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 143                 return -1;
 144             }
 145
 146             block[j] = level;
 147         }
 148         CLOSE_READER(re, &s->gb);
 149     }
 150     s->block_last_index[n] = i;
 151    return 0;
 152 }
 153
 154 int ff_mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
 155 {
 156     return mpeg1_decode_block_intra(s, block, n);
 157 }
 158
 159 static inline int mpeg1_decode_block_inter(MpegEncContext *s, int16_t *block, int n)
 160 {
 161     int level, i, j, run;
 162     RLTable *rl = &ff_rl_mpeg1;
 163     uint8_t * const scantable    = s->intra_scantable.permutated;
 164     const uint16_t *quant_matrix = s->inter_matrix;
 165     const int qscale             = s->qscale;
 166
 167     {
 168         OPEN_READER(re, &s->gb);
 169         i = -1;
 170         // special case for first coefficient, no need to add second VLC table
 171         UPDATE_CACHE(re, &s->gb);
 172         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 173             level = (3 * qscale * quant_matrix[0]) >> 5;
 174             level = (level - 1) | 1;
 175             if (GET_CACHE(re, &s->gb) & 0x40000000)
 176                 level = -level;
 177             block[0] = level;
 178             i++;
 179             SKIP_BITS(re, &s->gb, 2);
 180             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 181                 goto end;
 182         }
 183         /* now quantify & encode AC coefficients */
 184         for (;;) {
 185             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 186
 187             if (level != 0) {
 188                 i += run;
 189                 j = scantable[i];
 190                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 191                 level = (level - 1) | 1;
 192                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 193                 SKIP_BITS(re, &s->gb, 1);
 194             } else {
 195                 /* escape */
 196                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
 197                 UPDATE_CACHE(re, &s->gb);
 198                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 199                 if (level == -128) {
 200                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
 201                 } else if (level == 0) {
 202                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
 203                 }
 204                 i += run;
 205                 j = scantable[i];
 206                 if (level < 0) {
 207                     level = -level;
 208                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 209                     level = (level - 1) | 1;
 210                     level = -level;
 211                 } else {
 212                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 213                     level = (level - 1) | 1;
 214                 }
 215             }
 216             if (i > 63) {
 217                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 218                 return -1;
 219             }
 220
 221             block[j] = level;
 222             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 223                 break;
 224             UPDATE_CACHE(re, &s->gb);
 225         }
 226 end:
 227         LAST_SKIP_BITS(re, &s->gb, 2);
 228         CLOSE_READER(re, &s->gb);
 229     }
 230     s->block_last_index[n] = i;
 231     return 0;
 232 }
 233
 234 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, int16_t *block, int n)
 235 {
 236     int level, i, j, run;
 237     RLTable *rl = &ff_rl_mpeg1;
 238     uint8_t * const scantable = s->intra_scantable.permutated;
 239     const int qscale          = s->qscale;
 240
 241     {
 242         OPEN_READER(re, &s->gb);
 243         i = -1;
 244         // special case for first coefficient, no need to add second VLC table
 245         UPDATE_CACHE(re, &s->gb);
 246         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 247             level = (3 * qscale) >> 1;
 248             level = (level - 1) | 1;
 249             if (GET_CACHE(re, &s->gb) & 0x40000000)
 250                 level = -level;
 251             block[0] = level;
 252             i++;
 253             SKIP_BITS(re, &s->gb, 2);
 254             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 255                 goto end;
 256         }
 257
 258         /* now quantify & encode AC coefficients */
 259         for (;;) {
 260             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 261
 262             if (level != 0) {
 263                 i += run;
 264                 j = scantable[i];
 265                 level = ((level * 2 + 1) * qscale) >> 1;
 266                 level = (level - 1) | 1;
 267                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 268                 SKIP_BITS(re, &s->gb, 1);
 269             } else {
 270                 /* escape */
 271                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 272                 UPDATE_CACHE(re, &s->gb);
 273                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 274                 if (level == -128) {
 275                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
 276                 } else if (level == 0) {
 277                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
 278                 }
 279                 i += run;
 280                 j = scantable[i];
 281                 if (level < 0) {
 282                     level = -level;
 283                     level = ((level * 2 + 1) * qscale) >> 1;
 284                     level = (level - 1) | 1;
 285                     level = -level;
 286                 } else {
 287                     level = ((level * 2 + 1) * qscale) >> 1;
 288                     level = (level - 1) | 1;
 289                 }
 290             }
 291
 292             block[j] = level;
 293             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 294                 break;
 295             UPDATE_CACHE(re, &s->gb);
 296         }
 297 end:
 298         LAST_SKIP_BITS(re, &s->gb, 2);
 299         CLOSE_READER(re, &s->gb);
 300     }
 301     s->block_last_index[n] = i;
 302     return 0;
 303 }
 304
 305
 306 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s, int16_t *block, int n)
 307 {
 308     int level, i, j, run;
 309     RLTable *rl = &ff_rl_mpeg1;
 310     uint8_t * const scantable = s->intra_scantable.permutated;
 311     const uint16_t *quant_matrix;
 312     const int qscale = s->qscale;
 313     int mismatch;
 314
 315     mismatch = 1;
 316
 317     {
 318         OPEN_READER(re, &s->gb);
 319         i = -1;
 320         if (n < 4)
 321             quant_matrix = s->inter_matrix;
 322         else
 323             quant_matrix = s->chroma_inter_matrix;
 324
 325         // special case for first coefficient, no need to add second VLC table
 326         UPDATE_CACHE(re, &s->gb);
 327         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 328             level= (3 * qscale * quant_matrix[0]) >> 5;
 329             if (GET_CACHE(re, &s->gb) & 0x40000000)
 330                 level = -level;
 331             block[0]  = level;
 332             mismatch ^= level;
 333             i++;
 334             SKIP_BITS(re, &s->gb, 2);
 335             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 336                 goto end;
 337         }
 338
 339         /* now quantify & encode AC coefficients */
 340         for (;;) {
 341             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 342
 343             if (level != 0) {
 344                 i += run;
 345                 j = scantable[i];
 346                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 347                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 348                 SKIP_BITS(re, &s->gb, 1);
 349             } else {
 350                 /* escape */
 351                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
 352                 UPDATE_CACHE(re, &s->gb);
 353                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
 354
 355                 i += run;
 356                 j = scantable[i];
 357                 if (level < 0) {
 358                     level = ((-level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 359                     level = -level;
 360                 } else {
 361                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 362                 }
 363             }
 364             if (i > 63) {
 365                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 366                 return -1;
 367             }
 368
 369             mismatch ^= level;
 370             block[j]  = level;
 371             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 372                 break;
 373             UPDATE_CACHE(re, &s->gb);
 374         }
 375 end:
 376         LAST_SKIP_BITS(re, &s->gb, 2);
 377         CLOSE_READER(re, &s->gb);
 378     }
 379     block[63] ^= (mismatch & 1);
 380
 381     s->block_last_index[n] = i;
 382     return 0;
 383 }
 384
 385 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
 386                                                     int16_t *block, int n)
 387 {
 388     int level, i, j, run;
 389     RLTable *rl = &ff_rl_mpeg1;
 390     uint8_t * const scantable = s->intra_scantable.permutated;
 391     const int qscale          = s->qscale;
 392     OPEN_READER(re, &s->gb);
 393     i = -1;
 394
 395     // special case for first coefficient, no need to add second VLC table
 396     UPDATE_CACHE(re, &s->gb);
 397     if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 398         level = (3 * qscale) >> 1;
 399         if (GET_CACHE(re, &s->gb) & 0x40000000)
 400             level = -level;
 401         block[0] = level;
 402         i++;
 403         SKIP_BITS(re, &s->gb, 2);
 404         if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 405             goto end;
 406     }
 407
 408     /* now quantify & encode AC coefficients */
 409     for (;;) {
 410         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 411
 412         if (level != 0) {
 413             i += run;
 414             j  = scantable[i];
 415             level = ((level * 2 + 1) * qscale) >> 1;
 416             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 417             SKIP_BITS(re, &s->gb, 1);
 418         } else {
 419             /* escape */
 420             run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
 421             UPDATE_CACHE(re, &s->gb);
 422             level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
 423
 424             i += run;
 425             j  = scantable[i];
 426             if (level < 0) {
 427                 level = ((-level * 2 + 1) * qscale) >> 1;
 428                 level = -level;
 429             } else {
 430                 level = ((level * 2 + 1) * qscale) >> 1;
 431             }
 432         }
 433
 434         block[j] = level;
 435         if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 436             break;
 437         UPDATE_CACHE(re, &s->gb);
 438     }
 439 end:
 440     LAST_SKIP_BITS(re, &s->gb, 2);
 441     CLOSE_READER(re, &s->gb);
 442     s->block_last_index[n] = i;
 443     return 0;
 444 }
 445
 446
 447 static inline int mpeg2_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
 448 {
 449     int level, dc, diff, i, j, run;
 450     int component;
 451     RLTable *rl;
 452     uint8_t * const scantable = s->intra_scantable.permutated;
 453     const uint16_t *quant_matrix;
 454     const int qscale = s->qscale;
 455     int mismatch;
 456
 457     /* DC coefficient */
 458     if (n < 4) {
 459         quant_matrix = s->intra_matrix;
 460         component = 0;
 461     } else {
 462         quant_matrix = s->chroma_intra_matrix;
 463         component = (n & 1) + 1;
 464     }
 465     diff = decode_dc(&s->gb, component);
 466     if (diff >= 0xffff)
 467         return -1;
 468     dc  = s->last_dc[component];
 469     dc += diff;
 470     s->last_dc[component] = dc;
 471     block[0] = dc << (3 - s->intra_dc_precision);
 472     av_dlog(s->avctx, "dc=%d\n", block[0]);
 473     mismatch = block[0] ^ 1;
 474     i = 0;
 475     if (s->intra_vlc_format)
 476         rl = &ff_rl_mpeg2;
 477     else
 478         rl = &ff_rl_mpeg1;
 479
 480     {
 481         OPEN_READER(re, &s->gb);
 482         /* now quantify & encode AC coefficients */
 483         for (;;) {
 484             UPDATE_CACHE(re, &s->gb);
 485             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 486
 487             if (level == 127) {
 488                 break;
 489             } else if (level != 0) {
 490                 i += run;
 491                 j  = scantable[i];
 492                 level = (level * qscale * quant_matrix[j]) >> 4;
 493                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 494                 LAST_SKIP_BITS(re, &s->gb, 1);
 495             } else {
 496                 /* escape */
 497                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
 498                 UPDATE_CACHE(re, &s->gb);
 499                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
 500                 i += run;
 501                 j  = scantable[i];
 502                 if (level < 0) {
 503                     level = (-level * qscale * quant_matrix[j]) >> 4;
 504                     level = -level;
 505                 } else {
 506                     level = (level * qscale * quant_matrix[j]) >> 4;
 507                 }
 508             }
 509             if (i > 63) {
 510                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 511                 return -1;
 512             }
 513
 514             mismatch ^= level;
 515             block[j]  = level;
 516         }
 517         CLOSE_READER(re, &s->gb);
 518     }
 519     block[63] ^= mismatch & 1;
 520
 521     s->block_last_index[n] = i;
 522     return 0;
 523 }
 524
 525 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
 526 {
 527     int level, dc, diff, j, run;
 528     int component;
 529     RLTable *rl;
 530     uint8_t * scantable = s->intra_scantable.permutated;
 531     const uint16_t *quant_matrix;
 532     const int qscale = s->qscale;
 533
 534     /* DC coefficient */
 535     if (n < 4) {
 536         quant_matrix = s->intra_matrix;
 537         component = 0;
 538     } else {
 539         quant_matrix = s->chroma_intra_matrix;
 540         component = (n & 1) + 1;
 541     }
 542     diff = decode_dc(&s->gb, component);
 543     if (diff >= 0xffff)
 544         return -1;
 545     dc = s->last_dc[component];
 546     dc += diff;
 547     s->last_dc[component] = dc;
 548     block[0] = dc << (3 - s->intra_dc_precision);
 549     if (s->intra_vlc_format)
 550         rl = &ff_rl_mpeg2;
 551     else
 552         rl = &ff_rl_mpeg1;
 553
 554     {
 555         OPEN_READER(re, &s->gb);
 556         /* now quantify & encode AC coefficients */
 557         for (;;) {
 558             UPDATE_CACHE(re, &s->gb);
 559             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 560
 561             if (level == 127) {
 562                 break;
 563             } else if (level != 0) {
 564                 scantable += run;
 565                 j = *scantable;
 566                 level = (level * qscale * quant_matrix[j]) >> 4;
 567                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 568                 LAST_SKIP_BITS(re, &s->gb, 1);
 569             } else {
 570                 /* escape */
 571                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
 572                 UPDATE_CACHE(re, &s->gb);
 573                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
 574                 scantable += run;
 575                 j = *scantable;
 576                 if (level < 0) {
 577                     level = (-level * qscale * quant_matrix[j]) >> 4;
 578                     level = -level;
 579                 } else {
 580                     level = (level * qscale * quant_matrix[j]) >> 4;
 581                 }
 582             }
 583
 584             block[j] = level;
 585         }
 586         CLOSE_READER(re, &s->gb);
 587     }
 588
 589     s->block_last_index[n] = scantable - s->intra_scantable.permutated;
 590     return 0;
 591 }
 592
 593 uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
 594
 595 #define INIT_2D_VLC_RL(rl, static_size)\
 596 {\
 597     static RL_VLC_ELEM rl_vlc_table[static_size];\
 598     INIT_VLC_STATIC(&rl.vlc, TEX_VLC_BITS, rl.n + 2,\
 599                     &rl.table_vlc[0][1], 4, 2,\
 600                     &rl.table_vlc[0][0], 4, 2, static_size);\
 601 \
 602     rl.rl_vlc[0] = rl_vlc_table;\
 603     init_2d_vlc_rl(&rl);\
 604 }
 605
 606 static void init_2d_vlc_rl(RLTable *rl)
 607 {
 608     int i;
 609
 610     for (i = 0; i < rl->vlc.table_size; i++) {
 611         int code = rl->vlc.table[i][0];
 612         int len  = rl->vlc.table[i][1];
 613         int level, run;
 614
 615         if (len == 0) { // illegal code
 616             run   = 65;
 617             level = MAX_LEVEL;
 618         } else if (len<0) { //more bits needed
 619             run   = 0;
 620             level = code;
 621         } else {
 622             if (code == rl->n) { //esc
 623                 run   = 65;
 624                 level = 0;
 625             } else if (code == rl->n+1) { //eob
 626                 run   = 0;
 627                 level = 127;
 628             } else {
 629                 run   = rl->table_run  [code] + 1;
 630                 level = rl->table_level[code];
 631             }
 632         }
 633         rl->rl_vlc[0][i].len   = len;
 634         rl->rl_vlc[0][i].level = level;
 635         rl->rl_vlc[0][i].run   = run;
 636     }
 637 }
 638
 639 void ff_mpeg12_common_init(MpegEncContext *s)
 640 {
 641
 642     s->y_dc_scale_table =
 643     s->c_dc_scale_table = ff_mpeg2_dc_scale_table[s->intra_dc_precision];
 644
 645 }
 646
 647 void ff_mpeg1_clean_buffers(MpegEncContext *s)
 648 {
 649     s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
 650     s->last_dc[1] = s->last_dc[0];
 651     s->last_dc[2] = s->last_dc[0];
 652     memset(s->last_mv, 0, sizeof(s->last_mv));
 653 }
 654
 655
 656 /******************************************/
 657 /* decoding */
 658
 659 VLC ff_dc_lum_vlc;
 660 VLC ff_dc_chroma_vlc;
 661
 662 static VLC mbincr_vlc;
 663 static VLC mb_ptype_vlc;
 664 static VLC mb_btype_vlc;
 665 static VLC mb_pat_vlc;
 666
 667 av_cold void ff_mpeg12_init_vlcs(void)
 668 {
 669     static int done = 0;
 670
 671     if (!done) {
 672         done = 1;
 673
 674         INIT_VLC_STATIC(&ff_dc_lum_vlc, DC_VLC_BITS, 12,
 675                         ff_mpeg12_vlc_dc_lum_bits, 1, 1,
 676                         ff_mpeg12_vlc_dc_lum_code, 2, 2, 512);
 677         INIT_VLC_STATIC(&ff_dc_chroma_vlc,  DC_VLC_BITS, 12,
 678                         ff_mpeg12_vlc_dc_chroma_bits, 1, 1,
 679                         ff_mpeg12_vlc_dc_chroma_code, 2, 2, 514);
 680         INIT_VLC_STATIC(&mv_vlc, MV_VLC_BITS, 17,
 681                         &ff_mpeg12_mbMotionVectorTable[0][1], 2, 1,
 682                         &ff_mpeg12_mbMotionVectorTable[0][0], 2, 1, 518);
 683         INIT_VLC_STATIC(&mbincr_vlc, MBINCR_VLC_BITS, 36,
 684                         &ff_mpeg12_mbAddrIncrTable[0][1], 2, 1,
 685                         &ff_mpeg12_mbAddrIncrTable[0][0], 2, 1, 538);
 686         INIT_VLC_STATIC(&mb_pat_vlc, MB_PAT_VLC_BITS, 64,
 687                         &ff_mpeg12_mbPatTable[0][1], 2, 1,
 688                         &ff_mpeg12_mbPatTable[0][0], 2, 1, 512);
 689
 690         INIT_VLC_STATIC(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7,
 691                         &table_mb_ptype[0][1], 2, 1,
 692                         &table_mb_ptype[0][0], 2, 1, 64);
 693         INIT_VLC_STATIC(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11,
 694                         &table_mb_btype[0][1], 2, 1,
 695                         &table_mb_btype[0][0], 2, 1, 64);
 696         ff_init_rl(&ff_rl_mpeg1, ff_mpeg12_static_rl_table_store[0]);
 697         ff_init_rl(&ff_rl_mpeg2, ff_mpeg12_static_rl_table_store[1]);
 698
 699         INIT_2D_VLC_RL(ff_rl_mpeg1, 680);
 700         INIT_2D_VLC_RL(ff_rl_mpeg2, 674);
 701     }
 702 }
 703
 704 static inline int get_dmv(MpegEncContext *s)
 705 {
 706     if (get_bits1(&s->gb))
 707         return 1 - (get_bits1(&s->gb) << 1);
 708     else
 709         return 0;
 710 }
 711
 712 static inline int get_qscale(MpegEncContext *s)
 713 {
 714     int qscale = get_bits(&s->gb, 5);
 715     if (s->q_scale_type) {
 716         return non_linear_qscale[qscale];
 717     } else {
 718         return qscale << 1;
 719     }
 720 }
 721
 722 static void exchange_uv(MpegEncContext *s)
 723 {
 724     int16_t (*tmp)[64];
 725
 726     tmp           = s->pblocks[4];
 727     s->pblocks[4] = s->pblocks[5];
 728     s->pblocks[5] = tmp;
 729 }
 730
 731 /* motion type (for MPEG-2) */
 732 #define MT_FIELD 1
 733 #define MT_FRAME 2
 734 #define MT_16X8  2
 735 #define MT_DMV   3
 736
 737 static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
 738 {
 739     int i, j, k, cbp, val, mb_type, motion_type;
 740     const int mb_block_count = 4 + (1 << s->chroma_format);
 741
 742     av_dlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
 743
 744     assert(s->mb_skipped == 0);
 745
 746     if (s->mb_skip_run-- != 0) {
 747         if (s->pict_type == AV_PICTURE_TYPE_P) {
 748             s->mb_skipped = 1;
 749             s->current_picture.f.mb_type[s->mb_x + s->mb_y * s->mb_stride] = MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 750         } else {
 751             int mb_type;
 752
 753             if (s->mb_x)
 754                 mb_type = s->current_picture.f.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1];
 755             else
 756                 mb_type = s->current_picture.f.mb_type[s->mb_width + (s->mb_y - 1) * s->mb_stride - 1]; // FIXME not sure if this is allowed in MPEG at all
 757             if (IS_INTRA(mb_type))
 758                 return -1;
 759             s->current_picture.f.mb_type[s->mb_x + s->mb_y*s->mb_stride] =
 760                 mb_type | MB_TYPE_SKIP;
 761 //            assert(s->current_picture.f.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1] & (MB_TYPE_16x16 | MB_TYPE_16x8));
 762
 763             if ((s->mv[0][0][0] | s->mv[0][0][1] | s->mv[1][0][0] | s->mv[1][0][1]) == 0)
 764                 s->mb_skipped = 1;
 765         }
 766
 767         return 0;
 768     }
 769
 770     switch (s->pict_type) {
 771     default:
 772     case AV_PICTURE_TYPE_I:
 773         if (get_bits1(&s->gb) == 0) {
 774             if (get_bits1(&s->gb) == 0) {
 775                 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
 776                 return -1;
 777             }
 778             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
 779         } else {
 780             mb_type = MB_TYPE_INTRA;
 781         }
 782         break;
 783     case AV_PICTURE_TYPE_P:
 784         mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
 785         if (mb_type < 0) {
 786             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
 787             return -1;
 788         }
 789         mb_type = ptype2mb_type[mb_type];
 790         break;
 791     case AV_PICTURE_TYPE_B:
 792         mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
 793         if (mb_type < 0) {
 794             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
 795             return -1;
 796         }
 797         mb_type = btype2mb_type[mb_type];
 798         break;
 799     }
 800     av_dlog(s->avctx, "mb_type=%x\n", mb_type);
 801 //    motion_type = 0; /* avoid warning */
 802     if (IS_INTRA(mb_type)) {
 803         s->dsp.clear_blocks(s->block[0]);
 804
 805         if (!s->chroma_y_shift) {
 806             s->dsp.clear_blocks(s->block[6]);
 807         }
 808
 809         /* compute DCT type */
 810         if (s->picture_structure == PICT_FRAME && // FIXME add an interlaced_dct coded var?
 811             !s->frame_pred_frame_dct) {
 812             s->interlaced_dct = get_bits1(&s->gb);
 813         }
 814
 815         if (IS_QUANT(mb_type))
 816             s->qscale = get_qscale(s);
 817
 818         if (s->concealment_motion_vectors) {
 819             /* just parse them */
 820             if (s->picture_structure != PICT_FRAME)
 821                 skip_bits1(&s->gb); /* field select */
 822
 823             s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
 824                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
 825             s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
 826                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
 827
 828             skip_bits1(&s->gb); /* marker */
 829         } else
 830             memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
 831         s->mb_intra = 1;
 832         // if 1, we memcpy blocks in xvmcvideo
 833         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1) {
 834             ff_xvmc_pack_pblocks(s, -1); // inter are always full blocks
 835             if (s->swap_uv) {
 836                 exchange_uv(s);
 837             }
 838         }
 839
 840         if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
 841             if (s->flags2 & CODEC_FLAG2_FAST) {
 842                 for (i = 0; i < 6; i++) {
 843                     mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
 844                 }
 845             } else {
 846                 for (i = 0; i < mb_block_count; i++) {
 847                     if (mpeg2_decode_block_intra(s, *s->pblocks[i], i) < 0)
 848                         return -1;
 849                 }
 850             }
 851         } else {
 852             for (i = 0; i < 6; i++) {
 853                 if (mpeg1_decode_block_intra(s, *s->pblocks[i], i) < 0)
 854                     return -1;
 855             }
 856         }
 857     } else {
 858         if (mb_type & MB_TYPE_ZERO_MV) {
 859             assert(mb_type & MB_TYPE_CBP);
 860
 861             s->mv_dir = MV_DIR_FORWARD;
 862             if (s->picture_structure == PICT_FRAME) {
 863                 if (!s->frame_pred_frame_dct)
 864                     s->interlaced_dct = get_bits1(&s->gb);
 865                 s->mv_type = MV_TYPE_16X16;
 866             } else {
 867                 s->mv_type = MV_TYPE_FIELD;
 868                 mb_type |= MB_TYPE_INTERLACED;
 869                 s->field_select[0][0] = s->picture_structure - 1;
 870             }
 871
 872             if (IS_QUANT(mb_type))
 873                 s->qscale = get_qscale(s);
 874
 875             s->last_mv[0][0][0] = 0;
 876             s->last_mv[0][0][1] = 0;
 877             s->last_mv[0][1][0] = 0;
 878             s->last_mv[0][1][1] = 0;
 879             s->mv[0][0][0] = 0;
 880             s->mv[0][0][1] = 0;
 881         } else {
 882             assert(mb_type & MB_TYPE_L0L1);
 883             // FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
 884             /* get additional motion vector type */
 885             if (s->frame_pred_frame_dct)
 886                 motion_type = MT_FRAME;
 887             else {
 888                 motion_type = get_bits(&s->gb, 2);
 889                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
 890                     s->interlaced_dct = get_bits1(&s->gb);
 891             }
 892
 893             if (IS_QUANT(mb_type))
 894                 s->qscale = get_qscale(s);
 895
 896             /* motion vectors */
 897             s->mv_dir = (mb_type >> 13) & 3;
 898             av_dlog(s->avctx, "motion_type=%d\n", motion_type);
 899             switch (motion_type) {
 900             case MT_FRAME: /* or MT_16X8 */
 901                 if (s->picture_structure == PICT_FRAME) {
 902                     mb_type |= MB_TYPE_16x16;
 903                     s->mv_type = MV_TYPE_16X16;
 904                     for (i = 0; i < 2; i++) {
 905                         if (USES_LIST(mb_type, i)) {
 906                             /* MT_FRAME */
 907                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =
 908                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
 909                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =
 910                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
 911                             /* full_pel: only for MPEG-1 */
 912                             if (s->full_pel[i]) {
 913                                 s->mv[i][0][0] <<= 1;
 914                                 s->mv[i][0][1] <<= 1;
 915                             }
 916                         }
 917                     }
 918                 } else {
 919                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 920                     s->mv_type = MV_TYPE_16X8;
 921                     for (i = 0; i < 2; i++) {
 922                         if (USES_LIST(mb_type, i)) {
 923                             /* MT_16X8 */
 924                             for (j = 0; j < 2; j++) {
 925                                 s->field_select[i][j] = get_bits1(&s->gb);
 926                                 for (k = 0; k < 2; k++) {
 927                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 928                                                              s->last_mv[i][j][k]);
 929                                     s->last_mv[i][j][k] = val;
 930                                     s->mv[i][j][k]      = val;
 931                                 }
 932                             }
 933                         }
 934                     }
 935                 }
 936                 break;
 937             case MT_FIELD:
 938                 s->mv_type = MV_TYPE_FIELD;
 939                 if (s->picture_structure == PICT_FRAME) {
 940                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 941                     for (i = 0; i < 2; i++) {
 942                         if (USES_LIST(mb_type, i)) {
 943                             for (j = 0; j < 2; j++) {
 944                                 s->field_select[i][j] = get_bits1(&s->gb);
 945                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 946                                                          s->last_mv[i][j][0]);
 947                                 s->last_mv[i][j][0] = val;
 948                                 s->mv[i][j][0]      = val;
 949                                 av_dlog(s->avctx, "fmx=%d\n", val);
 950                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 951                                                          s->last_mv[i][j][1] >> 1);
 952                                 s->last_mv[i][j][1] = val << 1;
 953                                 s->mv[i][j][1]      = val;
 954                                 av_dlog(s->avctx, "fmy=%d\n", val);
 955                             }
 956                         }
 957                     }
 958                 } else {
 959                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 960                     for (i = 0; i < 2; i++) {
 961                         if (USES_LIST(mb_type, i)) {
 962                             s->field_select[i][0] = get_bits1(&s->gb);
 963                             for (k = 0; k < 2; k++) {
 964                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 965                                                          s->last_mv[i][0][k]);
 966                                 s->last_mv[i][0][k] = val;
 967                                 s->last_mv[i][1][k] = val;
 968                                 s->mv[i][0][k]      = val;
 969                             }
 970                         }
 971                     }
 972                 }
 973                 break;
 974             case MT_DMV:
 975                 s->mv_type = MV_TYPE_DMV;
 976                 for (i = 0; i < 2; i++) {
 977                     if (USES_LIST(mb_type, i)) {
 978                         int dmx, dmy, mx, my, m;
 979                         const int my_shift = s->picture_structure == PICT_FRAME;
 980
 981                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 982                                                 s->last_mv[i][0][0]);
 983                         s->last_mv[i][0][0] = mx;
 984                         s->last_mv[i][1][0] = mx;
 985                         dmx = get_dmv(s);
 986                         my  = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 987                                                  s->last_mv[i][0][1] >> my_shift);
 988                         dmy = get_dmv(s);
 989
 990
 991                         s->last_mv[i][0][1] = my << my_shift;
 992                         s->last_mv[i][1][1] = my << my_shift;
 993
 994                         s->mv[i][0][0] = mx;
 995                         s->mv[i][0][1] = my;
 996                         s->mv[i][1][0] = mx; // not used
 997                         s->mv[i][1][1] = my; // not used
 998
 999                         if (s->picture_structure == PICT_FRAME) {
1000                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
1001
1002                             // m = 1 + 2 * s->top_field_first;
1003                             m = s->top_field_first ? 1 : 3;
1004
1005                             /* top -> top pred */
1006                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1007                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
1008                             m = 4 - m;
1009                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1010                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
1011                         } else {
1012                             mb_type |= MB_TYPE_16x16;
1013
1014                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
1015                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
1016                             if (s->picture_structure == PICT_TOP_FIELD)
1017                                 s->mv[i][2][1]--;
1018                             else
1019                                 s->mv[i][2][1]++;
1020                         }
1021                     }
1022                 }
1023                 break;
1024             default:
1025                 av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
1026                 return -1;
1027             }
1028         }
1029
1030         s->mb_intra = 0;
1031         if (HAS_CBP(mb_type)) {
1032             s->dsp.clear_blocks(s->block[0]);
1033
1034             cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
1035             if (mb_block_count > 6) {
1036                  cbp <<= mb_block_count - 6;
1037                  cbp  |= get_bits(&s->gb, mb_block_count - 6);
1038                  s->dsp.clear_blocks(s->block[6]);
1039             }
1040             if (cbp <= 0) {
1041                 av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
1042                 return -1;
1043             }
1044
1045             //if 1, we memcpy blocks in xvmcvideo
1046             if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1) {
1047                 ff_xvmc_pack_pblocks(s, cbp);
1048                 if (s->swap_uv) {
1049                     exchange_uv(s);
1050                 }
1051             }
1052
1053             if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
1054                 if (s->flags2 & CODEC_FLAG2_FAST) {
1055                     for (i = 0; i < 6; i++) {
1056                         if (cbp & 32) {
1057                             mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
1058                         } else {
1059                             s->block_last_index[i] = -1;
1060                         }
1061                         cbp += cbp;
1062                     }
1063                 } else {
1064                     cbp <<= 12-mb_block_count;
1065
1066                     for (i = 0; i < mb_block_count; i++) {
1067                         if (cbp & (1 << 11)) {
1068                             if (mpeg2_decode_block_non_intra(s, *s->pblocks[i], i) < 0)
1069                                 return -1;
1070                         } else {
1071                             s->block_last_index[i] = -1;
1072                         }
1073                         cbp += cbp;
1074                     }
1075                 }
1076             } else {
1077                 if (s->flags2 & CODEC_FLAG2_FAST) {
1078                     for (i = 0; i < 6; i++) {
1079                         if (cbp & 32) {
1080                             mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
1081                         } else {
1082                             s->block_last_index[i] = -1;
1083                         }
1084                         cbp += cbp;
1085                     }
1086                 } else {
1087                     for (i = 0; i < 6; i++) {
1088                         if (cbp & 32) {
1089                             if (mpeg1_decode_block_inter(s, *s->pblocks[i], i) < 0)
1090                                 return -1;
1091                         } else {
1092                             s->block_last_index[i] = -1;
1093                         }
1094                         cbp += cbp;
1095                     }
1096                 }
1097             }
1098         } else {
1099             for (i = 0; i < 12; i++)
1100                 s->block_last_index[i] = -1;
1101         }
1102     }
1103
1104     s->current_picture.f.mb_type[s->mb_x + s->mb_y * s->mb_stride] = mb_type;
1105
1106     return 0;
1107 }
1108
1109 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1110 {
1111     Mpeg1Context *s = avctx->priv_data;
1112     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1113     int i;
1114
1115     /* we need some permutation to store matrices,
1116      * until MPV_common_init() sets the real permutation. */
1117     for (i = 0; i < 64; i++)
1118        s2->dsp.idct_permutation[i]=i;
1119
1120     ff_MPV_decode_defaults(s2);
1121
1122     s->mpeg_enc_ctx.avctx  = avctx;
1123     s->mpeg_enc_ctx.flags  = avctx->flags;
1124     s->mpeg_enc_ctx.flags2 = avctx->flags2;
1125     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1126     ff_mpeg12_init_vlcs();
1127
1128     s->mpeg_enc_ctx_allocated      = 0;
1129     s->mpeg_enc_ctx.picture_number = 0;
1130     s->repeat_field                = 0;
1131     s->mpeg_enc_ctx.codec_id       = avctx->codec->id;
1132     avctx->color_range = AVCOL_RANGE_MPEG;
1133     if (avctx->codec->id == AV_CODEC_ID_MPEG1VIDEO)
1134         avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
1135     else
1136         avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
1137     return 0;
1138 }
1139
1140 static int mpeg_decode_update_thread_context(AVCodecContext *avctx, const AVCodecContext *avctx_from)
1141 {
1142     Mpeg1Context *ctx = avctx->priv_data, *ctx_from = avctx_from->priv_data;
1143     MpegEncContext *s = &ctx->mpeg_enc_ctx, *s1 = &ctx_from->mpeg_enc_ctx;
1144     int err;
1145
1146     if (avctx == avctx_from || !ctx_from->mpeg_enc_ctx_allocated || !s1->context_initialized)
1147         return 0;
1148
1149     err = ff_mpeg_update_thread_context(avctx, avctx_from);
1150     if (err) return err;
1151
1152     if (!ctx->mpeg_enc_ctx_allocated)
1153         memcpy(s + 1, s1 + 1, sizeof(Mpeg1Context) - sizeof(MpegEncContext));
1154
1155     if (!(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay))
1156         s->picture_number++;
1157
1158     return 0;
1159 }
1160
1161 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1162                                  const uint8_t *new_perm)
1163 {
1164     uint16_t temp_matrix[64];
1165     int i;
1166
1167     memcpy(temp_matrix, matrix, 64 * sizeof(uint16_t));
1168
1169     for (i = 0; i < 64; i++) {
1170         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1171     }
1172 }
1173
1174 static const enum AVPixelFormat pixfmt_xvmc_mpg2_420[] = {
1175     AV_PIX_FMT_XVMC_MPEG2_IDCT,
1176     AV_PIX_FMT_XVMC_MPEG2_MC,
1177     AV_PIX_FMT_NONE };
1178
1179 static enum AVPixelFormat mpeg_get_pixelformat(AVCodecContext *avctx)
1180 {
1181     Mpeg1Context *s1 = avctx->priv_data;
1182     MpegEncContext *s = &s1->mpeg_enc_ctx;
1183
1184     if (avctx->xvmc_acceleration)
1185         return avctx->get_format(avctx, pixfmt_xvmc_mpg2_420);
1186     else if (avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU) {
1187         if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO)
1188             return AV_PIX_FMT_VDPAU_MPEG1;
1189         else
1190             return AV_PIX_FMT_VDPAU_MPEG2;
1191     } else {
1192         if (s->chroma_format <  2)
1193             return avctx->get_format(avctx, ff_hwaccel_pixfmt_list_420);
1194         else if (s->chroma_format == 2)
1195             return AV_PIX_FMT_YUV422P;
1196         else
1197             return AV_PIX_FMT_YUV444P;
1198     }
1199 }
1200
1201 /* Call this function when we know all parameters.
1202  * It may be called in different places for MPEG-1 and MPEG-2. */
1203 static int mpeg_decode_postinit(AVCodecContext *avctx)
1204 {
1205     Mpeg1Context *s1 = avctx->priv_data;
1206     MpegEncContext *s = &s1->mpeg_enc_ctx;
1207     uint8_t old_permutation[64];
1208
1209     if ((s1->mpeg_enc_ctx_allocated == 0) ||
1210         avctx->coded_width  != s->width   ||
1211         avctx->coded_height != s->height  ||
1212         s1->save_width           != s->width                ||
1213         s1->save_height          != s->height               ||
1214         s1->save_aspect_info     != s->aspect_ratio_info    ||
1215         s1->save_progressive_seq != s->progressive_sequence ||
1216         0)
1217     {
1218
1219         if (s1->mpeg_enc_ctx_allocated) {
1220             ParseContext pc = s->parse_context;
1221             s->parse_context.buffer = 0;
1222             ff_MPV_common_end(s);
1223             s->parse_context = pc;
1224         }
1225
1226         if ((s->width == 0) || (s->height == 0))
1227             return -2;
1228
1229         avcodec_set_dimensions(avctx, s->width, s->height);
1230         avctx->bit_rate          = s->bit_rate;
1231         s1->save_aspect_info     = s->aspect_ratio_info;
1232         s1->save_width           = s->width;
1233         s1->save_height          = s->height;
1234         s1->save_progressive_seq = s->progressive_sequence;
1235
1236         /* low_delay may be forced, in this case we will have B-frames
1237          * that behave like P-frames. */
1238         avctx->has_b_frames = !s->low_delay;
1239
1240         if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1241             //MPEG-1 fps
1242             avctx->time_base.den = ff_mpeg12_frame_rate_tab[s->frame_rate_index].num;
1243             avctx->time_base.num = ff_mpeg12_frame_rate_tab[s->frame_rate_index].den;
1244             //MPEG-1 aspect
1245             avctx->sample_aspect_ratio = av_d2q(1.0/ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1246             avctx->ticks_per_frame=1;
1247         } else {//MPEG-2
1248         //MPEG-2 fps
1249             av_reduce(&s->avctx->time_base.den,
1250                       &s->avctx->time_base.num,
1251                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num*2,
1252                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1253                       1 << 30);
1254             avctx->ticks_per_frame = 2;
1255             //MPEG-2 aspect
1256             if (s->aspect_ratio_info > 1) {
1257                 AVRational dar =
1258                     av_mul_q(av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1259                                       (AVRational) {s1->pan_scan.width, s1->pan_scan.height}),
1260                              (AVRational) {s->width, s->height});
1261
1262                 // we ignore the spec here and guess a bit as reality does not match the spec, see for example
1263                 // res_change_ffmpeg_aspect.ts and sequence-display-aspect.mpg
1264                 // issue1613, 621, 562
1265                 if ((s1->pan_scan.width == 0) || (s1->pan_scan.height == 0) ||
1266                    (av_cmp_q(dar, (AVRational) {4, 3}) && av_cmp_q(dar, (AVRational) {16, 9}))) {
1267                     s->avctx->sample_aspect_ratio =
1268                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1269                                  (AVRational) {s->width, s->height});
1270                 } else {
1271                     s->avctx->sample_aspect_ratio =
1272                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1273                                  (AVRational) {s1->pan_scan.width, s1->pan_scan.height});
1274 //issue1613 4/3 16/9 -> 16/9
1275 //res_change_ffmpeg_aspect.ts 4/3 225/44 ->4/3
1276 //widescreen-issue562.mpg 4/3 16/9 -> 16/9
1277 //                    s->avctx->sample_aspect_ratio = av_mul_q(s->avctx->sample_aspect_ratio, (AVRational) {s->width, s->height});
1278                     av_dlog(avctx, "A %d/%d\n",
1279                             ff_mpeg2_aspect[s->aspect_ratio_info].num, ff_mpeg2_aspect[s->aspect_ratio_info].den);
1280                     av_dlog(avctx, "B %d/%d\n", s->avctx->sample_aspect_ratio.num,
1281                             s->avctx->sample_aspect_ratio.den);
1282                 }
1283             } else {
1284                 s->avctx->sample_aspect_ratio =
1285                     ff_mpeg2_aspect[s->aspect_ratio_info];
1286             }
1287         } // MPEG-2
1288
1289         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1290         avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
1291         // until then pix_fmt may be changed right after codec init
1292         if (avctx->pix_fmt == AV_PIX_FMT_XVMC_MPEG2_IDCT ||
1293             avctx->hwaccel                            ||
1294             s->avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)
1295             if (avctx->idct_algo == FF_IDCT_AUTO)
1296                 avctx->idct_algo = FF_IDCT_SIMPLE;
1297
1298         /* Quantization matrices may need reordering
1299          * if DCT permutation is changed. */
1300         memcpy(old_permutation, s->dsp.idct_permutation, 64 * sizeof(uint8_t));
1301
1302         if (ff_MPV_common_init(s) < 0)
1303             return -2;
1304
1305         quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->dsp.idct_permutation);
1306         quant_matrix_rebuild(s->inter_matrix,        old_permutation, s->dsp.idct_permutation);
1307         quant_matrix_rebuild(s->chroma_intra_matrix, old_permutation, s->dsp.idct_permutation);
1308         quant_matrix_rebuild(s->chroma_inter_matrix, old_permutation, s->dsp.idct_permutation);
1309
1310         s1->mpeg_enc_ctx_allocated = 1;
1311     }
1312     return 0;
1313 }
1314
1315 static int mpeg1_decode_picture(AVCodecContext *avctx,
1316                                 const uint8_t *buf, int buf_size)
1317 {
1318     Mpeg1Context *s1 = avctx->priv_data;
1319     MpegEncContext *s = &s1->mpeg_enc_ctx;
1320     int ref, f_code, vbv_delay;
1321
1322     init_get_bits(&s->gb, buf, buf_size*8);
1323
1324     ref = get_bits(&s->gb, 10); /* temporal ref */
1325     s->pict_type = get_bits(&s->gb, 3);
1326     if (s->pict_type == 0 || s->pict_type > 3)
1327         return -1;
1328
1329     vbv_delay = get_bits(&s->gb, 16);
1330     if (s->pict_type == AV_PICTURE_TYPE_P || s->pict_type == AV_PICTURE_TYPE_B) {
1331         s->full_pel[0] = get_bits1(&s->gb);
1332         f_code = get_bits(&s->gb, 3);
1333         if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
1334             return -1;
1335         s->mpeg_f_code[0][0] = f_code;
1336         s->mpeg_f_code[0][1] = f_code;
1337     }
1338     if (s->pict_type == AV_PICTURE_TYPE_B) {
1339         s->full_pel[1] = get_bits1(&s->gb);
1340         f_code = get_bits(&s->gb, 3);
1341         if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
1342             return -1;
1343         s->mpeg_f_code[1][0] = f_code;
1344         s->mpeg_f_code[1][1] = f_code;
1345     }
1346     s->current_picture.f.pict_type = s->pict_type;
1347     s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1348
1349     if (avctx->debug & FF_DEBUG_PICT_INFO)
1350         av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1351
1352     s->y_dc_scale = 8;
1353     s->c_dc_scale = 8;
1354     return 0;
1355 }
1356
1357 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1358 {
1359     MpegEncContext *s= &s1->mpeg_enc_ctx;
1360     int horiz_size_ext, vert_size_ext;
1361     int bit_rate_ext;
1362
1363     skip_bits(&s->gb, 1); /* profile and level esc*/
1364     s->avctx->profile       = get_bits(&s->gb, 3);
1365     s->avctx->level         = get_bits(&s->gb, 4);
1366     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
1367     s->chroma_format        = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1368     horiz_size_ext          = get_bits(&s->gb, 2);
1369     vert_size_ext           = get_bits(&s->gb, 2);
1370     s->width  |= (horiz_size_ext << 12);
1371     s->height |= (vert_size_ext  << 12);
1372     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1373     s->bit_rate += (bit_rate_ext << 18) * 400;
1374     skip_bits1(&s->gb); /* marker */
1375     s->avctx->rc_buffer_size += get_bits(&s->gb, 8) * 1024 * 16 << 10;
1376
1377     s->low_delay = get_bits1(&s->gb);
1378     if (s->flags & CODEC_FLAG_LOW_DELAY)
1379         s->low_delay = 1;
1380
1381     s1->frame_rate_ext.num = get_bits(&s->gb, 2) + 1;
1382     s1->frame_rate_ext.den = get_bits(&s->gb, 5) + 1;
1383
1384     av_dlog(s->avctx, "sequence extension\n");
1385     s->codec_id      = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
1386
1387     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1388         av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
1389                s->avctx->profile, s->avctx->level, s->avctx->rc_buffer_size, s->bit_rate);
1390
1391 }
1392
1393 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1394 {
1395     MpegEncContext *s = &s1->mpeg_enc_ctx;
1396     int color_description, w, h;
1397
1398     skip_bits(&s->gb, 3); /* video format */
1399     color_description = get_bits1(&s->gb);
1400     if (color_description) {
1401         s->avctx->color_primaries = get_bits(&s->gb, 8);
1402         s->avctx->color_trc       = get_bits(&s->gb, 8);
1403         s->avctx->colorspace      = get_bits(&s->gb, 8);
1404     }
1405     w = get_bits(&s->gb, 14);
1406     skip_bits(&s->gb, 1); //marker
1407     h = get_bits(&s->gb, 14);
1408     // remaining 3 bits are zero padding
1409
1410     s1->pan_scan.width  = 16 * w;
1411     s1->pan_scan.height = 16 * h;
1412
1413     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1414         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1415 }
1416
1417 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1418 {
1419     MpegEncContext *s = &s1->mpeg_enc_ctx;
1420     int i, nofco;
1421
1422     nofco = 1;
1423     if (s->progressive_sequence) {
1424         if (s->repeat_first_field) {
1425             nofco++;
1426             if (s->top_field_first)
1427                 nofco++;
1428         }
1429     } else {
1430         if (s->picture_structure == PICT_FRAME) {
1431             nofco++;
1432             if (s->repeat_first_field)
1433                 nofco++;
1434         }
1435     }
1436     for (i = 0; i < nofco; i++) {
1437         s1->pan_scan.position[i][0] = get_sbits(&s->gb, 16);
1438         skip_bits(&s->gb, 1); // marker
1439         s1->pan_scan.position[i][1] = get_sbits(&s->gb, 16);
1440         skip_bits(&s->gb, 1); // marker
1441     }
1442
1443     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1444         av_log(s->avctx, AV_LOG_DEBUG, "pde (%d,%d) (%d,%d) (%d,%d)\n",
1445                s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1446                s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1447                s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]);
1448 }
1449
1450 static int load_matrix(MpegEncContext *s, uint16_t matrix0[64], uint16_t matrix1[64], int intra)
1451 {
1452     int i;
1453
1454     for (i = 0; i < 64; i++) {
1455         int j = s->dsp.idct_permutation[ff_zigzag_direct[i]];
1456         int v = get_bits(&s->gb, 8);
1457         if (v == 0) {
1458             av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
1459             return -1;
1460         }
1461         if (intra && i == 0 && v != 8) {
1462             av_log(s->avctx, AV_LOG_ERROR, "intra matrix invalid, ignoring\n");
1463             v = 8; // needed by pink.mpg / issue1046
1464         }
1465         matrix0[j] = v;
1466         if (matrix1)
1467             matrix1[j] = v;
1468     }
1469     return 0;
1470 }
1471
1472 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1473 {
1474     av_dlog(s->avctx, "matrix extension\n");
1475
1476     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1477     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1478     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_intra_matrix, NULL           , 1);
1479     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_inter_matrix, NULL           , 0);
1480 }
1481
1482 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1483 {
1484     MpegEncContext *s = &s1->mpeg_enc_ctx;
1485
1486     s->full_pel[0] = s->full_pel[1] = 0;
1487     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1488     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1489     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1490     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1491     if (!s->pict_type && s1->mpeg_enc_ctx_allocated) {
1492         av_log(s->avctx, AV_LOG_ERROR, "Missing picture start code, guessing missing values\n");
1493         if (s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1] == 15) {
1494             if (s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1495                 s->pict_type = AV_PICTURE_TYPE_I;
1496             else
1497                 s->pict_type = AV_PICTURE_TYPE_P;
1498         } else
1499             s->pict_type = AV_PICTURE_TYPE_B;
1500         s->current_picture.f.pict_type = s->pict_type;
1501         s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1502     }
1503     s->intra_dc_precision         = get_bits(&s->gb, 2);
1504     s->picture_structure          = get_bits(&s->gb, 2);
1505     s->top_field_first            = get_bits1(&s->gb);
1506     s->frame_pred_frame_dct       = get_bits1(&s->gb);
1507     s->concealment_motion_vectors = get_bits1(&s->gb);
1508     s->q_scale_type               = get_bits1(&s->gb);
1509     s->intra_vlc_format           = get_bits1(&s->gb);
1510     s->alternate_scan             = get_bits1(&s->gb);
1511     s->repeat_first_field         = get_bits1(&s->gb);
1512     s->chroma_420_type            = get_bits1(&s->gb);
1513     s->progressive_frame          = get_bits1(&s->gb);
1514
1515     if (s->progressive_sequence && !s->progressive_frame) {
1516         s->progressive_frame = 1;
1517         av_log(s->avctx, AV_LOG_ERROR, "interlaced frame in progressive sequence, ignoring\n");
1518     }
1519
1520     if (s->picture_structure == 0 || (s->progressive_frame && s->picture_structure != PICT_FRAME)) {
1521         av_log(s->avctx, AV_LOG_ERROR, "picture_structure %d invalid, ignoring\n", s->picture_structure);
1522         s->picture_structure = PICT_FRAME;
1523     }
1524
1525     if (s->progressive_sequence && !s->frame_pred_frame_dct) {
1526         av_log(s->avctx, AV_LOG_WARNING, "invalid frame_pred_frame_dct\n");
1527     }
1528
1529     if (s->picture_structure == PICT_FRAME) {
1530         s->first_field = 0;
1531         s->v_edge_pos  = 16 * s->mb_height;
1532     } else {
1533         s->first_field ^= 1;
1534         s->v_edge_pos   = 8 * s->mb_height;
1535         memset(s->mbskip_table, 0, s->mb_stride * s->mb_height);
1536     }
1537
1538     if (s->alternate_scan) {
1539         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
1540         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);
1541     } else {
1542         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
1543         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
1544     }
1545
1546     /* composite display not parsed */
1547     av_dlog(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1548     av_dlog(s->avctx, "picture_structure=%d\n", s->picture_structure);
1549     av_dlog(s->avctx, "top field first=%d\n", s->top_field_first);
1550     av_dlog(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1551     av_dlog(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1552     av_dlog(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1553     av_dlog(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1554     av_dlog(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1555     av_dlog(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1556 }
1557
1558 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
1559 {
1560     AVCodecContext *avctx = s->avctx;
1561     Mpeg1Context *s1 = (Mpeg1Context*)s;
1562
1563     /* start frame decoding */
1564     if (s->first_field || s->picture_structure == PICT_FRAME) {
1565         if (ff_MPV_frame_start(s, avctx) < 0)
1566             return -1;
1567
1568         ff_er_frame_start(s);
1569
1570         /* first check if we must repeat the frame */
1571         s->current_picture_ptr->f.repeat_pict = 0;
1572         if (s->repeat_first_field) {
1573             if (s->progressive_sequence) {
1574                 if (s->top_field_first)
1575                     s->current_picture_ptr->f.repeat_pict = 4;
1576                 else
1577                     s->current_picture_ptr->f.repeat_pict = 2;
1578             } else if (s->progressive_frame) {
1579                 s->current_picture_ptr->f.repeat_pict = 1;
1580             }
1581         }
1582
1583         *s->current_picture_ptr->f.pan_scan = s1->pan_scan;
1584
1585         if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
1586             ff_thread_finish_setup(avctx);
1587     } else { // second field
1588         int i;
1589
1590         if (!s->current_picture_ptr) {
1591             av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1592             return -1;
1593         }
1594
1595         if (s->avctx->hwaccel &&
1596             (s->avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
1597             if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1598                 av_log(avctx, AV_LOG_ERROR, "hardware accelerator failed to decode first field\n");
1599         }
1600
1601         for (i = 0; i < 4; i++) {
1602             s->current_picture.f.data[i] = s->current_picture_ptr->f.data[i];
1603             if (s->picture_structure == PICT_BOTTOM_FIELD) {
1604                 s->current_picture.f.data[i] += s->current_picture_ptr->f.linesize[i];
1605             }
1606         }
1607     }
1608
1609     if (avctx->hwaccel) {
1610         if (avctx->hwaccel->start_frame(avctx, buf, buf_size) < 0)
1611             return -1;
1612     }
1613
1614 // MPV_frame_start will call this function too,
1615 // but we need to call it on every field
1616     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
1617         if (ff_xvmc_field_start(s, avctx) < 0)
1618             return -1;
1619
1620     return 0;
1621 }
1622
1623 #define DECODE_SLICE_ERROR -1
1624 #define DECODE_SLICE_OK     0
1625
1626 /**
1627  * Decode a slice.
1628  * MpegEncContext.mb_y must be set to the MB row from the startcode.
1629  * @return DECODE_SLICE_ERROR if the slice is damaged,
1630  *         DECODE_SLICE_OK if this slice is OK
1631  */
1632 static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
1633                              const uint8_t **buf, int buf_size)
1634 {
1635     AVCodecContext *avctx = s->avctx;
1636     const int field_pic   = s->picture_structure != PICT_FRAME;
1637
1638     s->resync_mb_x =
1639     s->resync_mb_y = -1;
1640
1641     assert(mb_y < s->mb_height);
1642
1643     init_get_bits(&s->gb, *buf, buf_size * 8);
1644
1645     ff_mpeg1_clean_buffers(s);
1646     s->interlaced_dct = 0;
1647
1648     s->qscale = get_qscale(s);
1649
1650     if (s->qscale == 0) {
1651         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1652         return -1;
1653     }
1654
1655     /* extra slice info */
1656     while (get_bits1(&s->gb) != 0) {
1657         skip_bits(&s->gb, 8);
1658     }
1659
1660     s->mb_x = 0;
1661
1662     if (mb_y == 0 && s->codec_tag == AV_RL32("SLIF")) {
1663         skip_bits1(&s->gb);
1664     } else {
1665         while (get_bits_left(&s->gb) > 0) {
1666             int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1667             if (code < 0) {
1668                 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1669                 return -1;
1670             }
1671             if (code >= 33) {
1672                 if (code == 33) {
1673                     s->mb_x += 33;
1674                 }
1675                 /* otherwise, stuffing, nothing to do */
1676             } else {
1677                 s->mb_x += code;
1678                 break;
1679             }
1680         }
1681     }
1682
1683     if (s->mb_x >= (unsigned)s->mb_width) {
1684         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1685         return -1;
1686     }
1687
1688     if (avctx->hwaccel) {
1689         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
1690         int start_code = -1;
1691         buf_end = avpriv_mpv_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
1692         if (buf_end < *buf + buf_size)
1693             buf_end -= 4;
1694         s->mb_y = mb_y;
1695         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
1696             return DECODE_SLICE_ERROR;
1697         *buf = buf_end;
1698         return DECODE_SLICE_OK;
1699     }
1700
1701     s->resync_mb_x = s->mb_x;
1702     s->resync_mb_y = s->mb_y = mb_y;
1703     s->mb_skip_run = 0;
1704     ff_init_block_index(s);
1705
1706     if (s->mb_y == 0 && s->mb_x == 0 && (s->first_field || s->picture_structure == PICT_FRAME)) {
1707         if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
1708              av_log(s->avctx, AV_LOG_DEBUG, "qp:%d fc:%2d%2d%2d%2d %s %s %s %s %s dc:%d pstruct:%d fdct:%d cmv:%d qtype:%d ivlc:%d rff:%d %s\n",
1709                     s->qscale, s->mpeg_f_code[0][0], s->mpeg_f_code[0][1], s->mpeg_f_code[1][0], s->mpeg_f_code[1][1],
1710                     s->pict_type == AV_PICTURE_TYPE_I ? "I" : (s->pict_type == AV_PICTURE_TYPE_P ? "P" : (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
1711                     s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"",
1712                     s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
1713                     s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
1714         }
1715     }
1716
1717     for (;;) {
1718         // If 1, we memcpy blocks in xvmcvideo.
1719         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
1720             ff_xvmc_init_block(s); // set s->block
1721
1722         if (mpeg_decode_mb(s, s->block) < 0)
1723             return -1;
1724
1725         if (s->current_picture.f.motion_val[0] && !s->encoding) { // note motion_val is normally NULL unless we want to extract the MVs
1726             const int wrap = s->b8_stride;
1727             int xy         = s->mb_x * 2 + s->mb_y * 2 * wrap;
1728             int b8_xy      = 4 * (s->mb_x + s->mb_y * s->mb_stride);
1729             int motion_x, motion_y, dir, i;
1730
1731             for (i = 0; i < 2; i++) {
1732                 for (dir = 0; dir < 2; dir++) {
1733                     if (s->mb_intra || (dir == 1 && s->pict_type != AV_PICTURE_TYPE_B)) {
1734                         motion_x = motion_y = 0;
1735                     } else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)) {
1736                         motion_x = s->mv[dir][0][0];
1737                         motion_y = s->mv[dir][0][1];
1738                     } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ {
1739                         motion_x = s->mv[dir][i][0];
1740                         motion_y = s->mv[dir][i][1];
1741                     }
1742
1743                     s->current_picture.f.motion_val[dir][xy    ][0] = motion_x;
1744                     s->current_picture.f.motion_val[dir][xy    ][1] = motion_y;
1745                     s->current_picture.f.motion_val[dir][xy + 1][0] = motion_x;
1746                     s->current_picture.f.motion_val[dir][xy + 1][1] = motion_y;
1747                     s->current_picture.f.ref_index [dir][b8_xy    ] =
1748                     s->current_picture.f.ref_index [dir][b8_xy + 1] = s->field_select[dir][i];
1749                     assert(s->field_select[dir][i] == 0 || s->field_select[dir][i] == 1);
1750                 }
1751                 xy += wrap;
1752                 b8_xy +=2;
1753             }
1754         }
1755
1756         s->dest[0] += 16;
1757         s->dest[1] += 16 >> s->chroma_x_shift;
1758         s->dest[2] += 16 >> s->chroma_x_shift;
1759
1760         ff_MPV_decode_mb(s, s->block);
1761
1762         if (++s->mb_x >= s->mb_width) {
1763             const int mb_size = 16;
1764
1765             ff_draw_horiz_band(s, mb_size*(s->mb_y >> field_pic), mb_size);
1766             ff_MPV_report_decode_progress(s);
1767
1768             s->mb_x = 0;
1769             s->mb_y += 1 << field_pic;
1770
1771             if (s->mb_y >= s->mb_height) {
1772                 int left   = get_bits_left(&s->gb);
1773                 int is_d10 = s->chroma_format == 2 && s->pict_type == AV_PICTURE_TYPE_I && avctx->profile == 0 && avctx->level == 5
1774                              && s->intra_dc_precision == 2 && s->q_scale_type == 1 && s->alternate_scan == 0
1775                              && s->progressive_frame == 0 /* vbv_delay == 0xBBB || 0xE10*/;
1776
1777                 if (left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10)
1778                     || ((avctx->err_recognition & AV_EF_BUFFER) && left > 8)) {
1779                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n", left, show_bits(&s->gb, FFMIN(left, 23)));
1780                     return -1;
1781                 } else
1782                     goto eos;
1783             }
1784
1785             ff_init_block_index(s);
1786         }
1787
1788         /* skip mb handling */
1789         if (s->mb_skip_run == -1) {
1790             /* read increment again */
1791             s->mb_skip_run = 0;
1792             for (;;) {
1793                 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1794                 if (code < 0) {
1795                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1796                     return -1;
1797                 }
1798                 if (code >= 33) {
1799                     if (code == 33) {
1800                         s->mb_skip_run += 33;
1801                     } else if (code == 35) {
1802                         if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
1803                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1804                             return -1;
1805                         }
1806                         goto eos; /* end of slice */
1807                     }
1808                     /* otherwise, stuffing, nothing to do */
1809                 } else {
1810                     s->mb_skip_run += code;
1811                     break;
1812                 }
1813             }
1814             if (s->mb_skip_run) {
1815                 int i;
1816                 if (s->pict_type == AV_PICTURE_TYPE_I) {
1817                     av_log(s->avctx, AV_LOG_ERROR, "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1818                     return -1;
1819                 }
1820
1821                 /* skip mb */
1822                 s->mb_intra = 0;
1823                 for (i = 0; i < 12; i++)
1824                     s->block_last_index[i] = -1;
1825                 if (s->picture_structure == PICT_FRAME)
1826                     s->mv_type = MV_TYPE_16X16;
1827                 else
1828                     s->mv_type = MV_TYPE_FIELD;
1829                 if (s->pict_type == AV_PICTURE_TYPE_P) {
1830                     /* if P type, zero motion vector is implied */
1831                     s->mv_dir             = MV_DIR_FORWARD;
1832                     s->mv[0][0][0]        = s->mv[0][0][1]      = 0;
1833                     s->last_mv[0][0][0]   = s->last_mv[0][0][1] = 0;
1834                     s->last_mv[0][1][0]   = s->last_mv[0][1][1] = 0;
1835                     s->field_select[0][0] = (s->picture_structure - 1) & 1;
1836                 } else {
1837                     /* if B type, reuse previous vectors and directions */
1838                     s->mv[0][0][0] = s->last_mv[0][0][0];
1839                     s->mv[0][0][1] = s->last_mv[0][0][1];
1840                     s->mv[1][0][0] = s->last_mv[1][0][0];
1841                     s->mv[1][0][1] = s->last_mv[1][0][1];
1842                 }
1843             }
1844         }
1845     }
1846 eos: // end of slice
1847     *buf += (get_bits_count(&s->gb)-1)/8;
1848     av_dlog(s, "y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1849     return 0;
1850 }
1851
1852 static int slice_decode_thread(AVCodecContext *c, void *arg)
1853 {
1854     MpegEncContext *s   = *(void**)arg;
1855     const uint8_t *buf  = s->gb.buffer;
1856     int mb_y            = s->start_mb_y;
1857     const int field_pic = s->picture_structure != PICT_FRAME;
1858
1859     s->error_count = (3 * (s->end_mb_y - s->start_mb_y) * s->mb_width) >> field_pic;
1860
1861     for (;;) {
1862         uint32_t start_code;
1863         int ret;
1864
1865         ret = mpeg_decode_slice(s, mb_y, &buf, s->gb.buffer_end - buf);
1866         emms_c();
1867         av_dlog(c, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
1868                 ret, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y,
1869                 s->start_mb_y, s->end_mb_y, s->error_count);
1870         if (ret < 0) {
1871             if (c->err_recognition & AV_EF_EXPLODE)
1872                 return ret;
1873             if (s->resync_mb_x >= 0 && s->resync_mb_y >= 0)
1874                 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
1875         } else {
1876             ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, ER_AC_END | ER_DC_END | ER_MV_END);
1877         }
1878
1879         if (s->mb_y == s->end_mb_y)
1880             return 0;
1881
1882         start_code = -1;
1883         buf = avpriv_mpv_find_start_code(buf, s->gb.buffer_end, &start_code);
1884         mb_y= (start_code - SLICE_MIN_START_CODE) << field_pic;
1885         if (s->picture_structure == PICT_BOTTOM_FIELD)
1886             mb_y++;
1887         if (mb_y < 0 || mb_y >= s->end_mb_y)
1888             return -1;
1889     }
1890 }
1891
1892 /**
1893  * Handle slice ends.
1894  * @return 1 if it seems to be the last slice
1895  */
1896 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
1897 {
1898     Mpeg1Context *s1 = avctx->priv_data;
1899     MpegEncContext *s = &s1->mpeg_enc_ctx;
1900
1901     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
1902         return 0;
1903
1904     if (s->avctx->hwaccel) {
1905         if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1906             av_log(avctx, AV_LOG_ERROR, "hardware accelerator failed to decode picture\n");
1907     }
1908
1909     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
1910         ff_xvmc_field_end(s);
1911
1912     /* end of slice reached */
1913     if (/*s->mb_y << field_pic == s->mb_height &&*/ !s->first_field) {
1914         /* end of image */
1915
1916         s->current_picture_ptr->f.qscale_type = FF_QSCALE_TYPE_MPEG2;
1917
1918         ff_er_frame_end(s);
1919
1920         ff_MPV_frame_end(s);
1921
1922         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
1923             *pict = s->current_picture_ptr->f;
1924             ff_print_debug_info(s, pict);
1925         } else {
1926             if (avctx->active_thread_type & FF_THREAD_FRAME)
1927                 s->picture_number++;
1928             /* latency of 1 frame for I- and P-frames */
1929             /* XXX: use another variable than picture_number */
1930             if (s->last_picture_ptr != NULL) {
1931                 *pict = s->last_picture_ptr->f;
1932                  ff_print_debug_info(s, pict);
1933             }
1934         }
1935
1936         return 1;
1937     } else {
1938         return 0;
1939     }
1940 }
1941
1942 static int mpeg1_decode_sequence(AVCodecContext *avctx,
1943                                  const uint8_t *buf, int buf_size)
1944 {
1945     Mpeg1Context *s1 = avctx->priv_data;
1946     MpegEncContext *s = &s1->mpeg_enc_ctx;
1947     int width, height;
1948     int i, v, j;
1949
1950     init_get_bits(&s->gb, buf, buf_size*8);
1951
1952     width  = get_bits(&s->gb, 12);
1953     height = get_bits(&s->gb, 12);
1954     if (width <= 0 || height <= 0)
1955         return -1;
1956     s->aspect_ratio_info = get_bits(&s->gb, 4);
1957     if (s->aspect_ratio_info == 0) {
1958         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
1959         if (avctx->err_recognition & AV_EF_BITSTREAM)
1960             return -1;
1961     }
1962     s->frame_rate_index = get_bits(&s->gb, 4);
1963     if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
1964         return -1;
1965     s->bit_rate = get_bits(&s->gb, 18) * 400;
1966     if (get_bits1(&s->gb) == 0) /* marker */
1967         return -1;
1968     s->width  = width;
1969     s->height = height;
1970
1971     s->avctx->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
1972     skip_bits(&s->gb, 1);
1973
1974     /* get matrix */
1975     if (get_bits1(&s->gb)) {
1976         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1977     } else {
1978         for (i = 0; i < 64; i++) {
1979             j = s->dsp.idct_permutation[i];
1980             v = ff_mpeg1_default_intra_matrix[i];
1981             s->intra_matrix[j]        = v;
1982             s->chroma_intra_matrix[j] = v;
1983         }
1984     }
1985     if (get_bits1(&s->gb)) {
1986         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1987     } else {
1988         for (i = 0; i < 64; i++) {
1989             int j = s->dsp.idct_permutation[i];
1990             v = ff_mpeg1_default_non_intra_matrix[i];
1991             s->inter_matrix[j]        = v;
1992             s->chroma_inter_matrix[j] = v;
1993         }
1994     }
1995
1996     if (show_bits(&s->gb, 23) != 0) {
1997         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
1998         return -1;
1999     }
2000
2001     /* we set MPEG-2 parameters so that it emulates MPEG-1 */
2002     s->progressive_sequence = 1;
2003     s->progressive_frame    = 1;
2004     s->picture_structure    = PICT_FRAME;
2005     s->frame_pred_frame_dct = 1;
2006     s->chroma_format        = 1;
2007     s->codec_id             = s->avctx->codec_id = AV_CODEC_ID_MPEG1VIDEO;
2008     s->out_format           = FMT_MPEG1;
2009     s->swap_uv              = 0; // AFAIK VCR2 does not have SEQ_HEADER
2010     if (s->flags & CODEC_FLAG_LOW_DELAY)
2011         s->low_delay = 1;
2012
2013     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2014         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
2015                s->avctx->rc_buffer_size, s->bit_rate);
2016
2017     return 0;
2018 }
2019
2020 static int vcr2_init_sequence(AVCodecContext *avctx)
2021 {
2022     Mpeg1Context *s1 = avctx->priv_data;
2023     MpegEncContext *s = &s1->mpeg_enc_ctx;
2024     int i, v;
2025
2026     /* start new MPEG-1 context decoding */
2027     s->out_format = FMT_MPEG1;
2028     if (s1->mpeg_enc_ctx_allocated) {
2029         ff_MPV_common_end(s);
2030     }
2031     s->width  = avctx->coded_width;
2032     s->height = avctx->coded_height;
2033     avctx->has_b_frames = 0; // true?
2034     s->low_delay = 1;
2035
2036     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
2037     avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
2038
2039     if (avctx->pix_fmt == AV_PIX_FMT_XVMC_MPEG2_IDCT || avctx->hwaccel ||
2040         s->avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)
2041         if (avctx->idct_algo == FF_IDCT_AUTO)
2042             avctx->idct_algo = FF_IDCT_SIMPLE;
2043
2044     if (ff_MPV_common_init(s) < 0)
2045         return -1;
2046     exchange_uv(s); // common init reset pblocks, so we swap them here
2047     s->swap_uv = 1; // in case of xvmc we need to swap uv for each MB
2048     s1->mpeg_enc_ctx_allocated = 1;
2049
2050     for (i = 0; i < 64; i++) {
2051         int j = s->dsp.idct_permutation[i];
2052         v = ff_mpeg1_default_intra_matrix[i];
2053         s->intra_matrix[j]        = v;
2054         s->chroma_intra_matrix[j] = v;
2055
2056         v = ff_mpeg1_default_non_intra_matrix[i];
2057         s->inter_matrix[j]        = v;
2058         s->chroma_inter_matrix[j] = v;
2059     }
2060
2061     s->progressive_sequence  = 1;
2062     s->progressive_frame     = 1;
2063     s->picture_structure     = PICT_FRAME;
2064     s->frame_pred_frame_dct  = 1;
2065     s->chroma_format         = 1;
2066     s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
2067     s1->save_width           = s->width;
2068     s1->save_height          = s->height;
2069     s1->save_progressive_seq = s->progressive_sequence;
2070     return 0;
2071 }
2072
2073
2074 static void mpeg_decode_user_data(AVCodecContext *avctx,
2075                                   const uint8_t *p, int buf_size)
2076 {
2077     const uint8_t *buf_end = p + buf_size;
2078
2079     /* we parse the DTG active format information */
2080     if (buf_end - p >= 5 &&
2081         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2082         int flags = p[4];
2083         p += 5;
2084         if (flags & 0x80) {
2085             /* skip event id */
2086             p += 2;
2087         }
2088         if (flags & 0x40) {
2089             if (buf_end - p < 1)
2090                 return;
2091             avctx->dtg_active_format = p[0] & 0x0f;
2092         }
2093     }
2094 }
2095
2096 static void mpeg_decode_gop(AVCodecContext *avctx,
2097                             const uint8_t *buf, int buf_size)
2098 {
2099     Mpeg1Context *s1  = avctx->priv_data;
2100     MpegEncContext *s = &s1->mpeg_enc_ctx;
2101
2102     int time_code_hours, time_code_minutes;
2103     int time_code_seconds, time_code_pictures;
2104     int broken_link;
2105
2106     init_get_bits(&s->gb, buf, buf_size*8);
2107
2108     skip_bits1(&s->gb); /* drop_frame_flag */
2109
2110     time_code_hours   = get_bits(&s->gb, 5);
2111     time_code_minutes = get_bits(&s->gb, 6);
2112     skip_bits1(&s->gb); // marker bit
2113     time_code_seconds  = get_bits(&s->gb, 6);
2114     time_code_pictures = get_bits(&s->gb, 6);
2115
2116     s1->closed_gop = get_bits1(&s->gb);
2117     /*broken_link indicate that after editing the
2118       reference frames of the first B-Frames after GOP I-Frame
2119       are missing (open gop)*/
2120     broken_link = get_bits1(&s->gb);
2121
2122     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2123         av_log(s->avctx, AV_LOG_DEBUG, "GOP (%2d:%02d:%02d.[%02d]) closed_gop=%d broken_link=%d\n",
2124                time_code_hours, time_code_minutes, time_code_seconds,
2125                time_code_pictures, s1->closed_gop, broken_link);
2126 }
2127 /**
2128  * Find the end of the current frame in the bitstream.
2129  * @return the position of the first byte of the next frame, or -1
2130  */
2131 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size, AVCodecParserContext *s)
2132 {
2133     int i;
2134     uint32_t state = pc->state;
2135
2136     /* EOF considered as end of frame */
2137     if (buf_size == 0)
2138         return 0;
2139
2140 /*
2141  0  frame start         -> 1/4
2142  1  first_SEQEXT        -> 0/2
2143  2  first field start   -> 3/0
2144  3  second_SEQEXT       -> 2/0
2145  4  searching end
2146 */
2147
2148     for (i = 0; i < buf_size; i++) {
2149         assert(pc->frame_start_found >= 0 && pc->frame_start_found <= 4);
2150         if (pc->frame_start_found & 1) {
2151             if (state == EXT_START_CODE && (buf[i] & 0xF0) != 0x80)
2152                 pc->frame_start_found--;
2153             else if (state == EXT_START_CODE + 2) {
2154                 if ((buf[i] & 3) == 3)
2155                     pc->frame_start_found = 0;
2156                 else
2157                     pc->frame_start_found = (pc->frame_start_found + 1) & 3;
2158             }
2159             state++;
2160         } else {
2161             i = avpriv_mpv_find_start_code(buf + i, buf + buf_size, &state) - buf - 1;
2162             if (pc->frame_start_found == 0 && state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE) {
2163                 i++;
2164                 pc->frame_start_found = 4;
2165             }
2166             if (state == SEQ_END_CODE) {
2167                 pc->frame_start_found = 0;
2168                 pc->state=-1;
2169                 return i+1;
2170             }
2171             if (pc->frame_start_found == 2 && state == SEQ_START_CODE)
2172                 pc->frame_start_found = 0;
2173             if (pc->frame_start_found  < 4 && state == EXT_START_CODE)
2174                 pc->frame_start_found++;
2175             if (pc->frame_start_found == 4 && (state & 0xFFFFFF00) == 0x100) {
2176                 if (state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE) {
2177                     pc->frame_start_found = 0;
2178                     pc->state             = -1;
2179                     return i - 3;
2180                 }
2181             }
2182             if (pc->frame_start_found == 0 && s && state == PICTURE_START_CODE) {
2183                 ff_fetch_timestamp(s, i - 3, 1);
2184             }
2185         }
2186     }
2187     pc->state = state;
2188     return END_NOT_FOUND;
2189 }
2190
2191 static int decode_chunks(AVCodecContext *avctx,
2192                          AVFrame *picture, int *got_output,
2193                          const uint8_t *buf, int buf_size)
2194 {
2195     Mpeg1Context *s = avctx->priv_data;
2196     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2197     const uint8_t *buf_ptr = buf;
2198     const uint8_t *buf_end = buf + buf_size;
2199     int ret, input_size;
2200     int last_code = 0;
2201
2202     for (;;) {
2203         /* find next start code */
2204         uint32_t start_code = -1;
2205         buf_ptr = avpriv_mpv_find_start_code(buf_ptr, buf_end, &start_code);
2206         if (start_code > 0x1ff) {
2207             if (s2->pict_type != AV_PICTURE_TYPE_B || avctx->skip_frame <= AVDISCARD_DEFAULT) {
2208                 if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE)) {
2209                     int i;
2210
2211                     avctx->execute(avctx, slice_decode_thread,  &s2->thread_context[0], NULL, s->slice_count, sizeof(void*));
2212                     for (i = 0; i < s->slice_count; i++)
2213                         s2->error_count += s2->thread_context[i]->error_count;
2214                 }
2215
2216                 if (CONFIG_MPEG_VDPAU_DECODER && avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)
2217                     ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
2218
2219                 if (slice_end(avctx, picture)) {
2220                     if (s2->last_picture_ptr || s2->low_delay) //FIXME merge with the stuff in mpeg_decode_slice
2221                         *got_output = 1;
2222                 }
2223             }
2224             s2->pict_type = 0;
2225             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2226         }
2227
2228         input_size = buf_end - buf_ptr;
2229
2230         if (avctx->debug & FF_DEBUG_STARTCODE) {
2231             av_log(avctx, AV_LOG_DEBUG, "%3X at %td left %d\n", start_code, buf_ptr-buf, input_size);
2232         }
2233
2234         /* prepare data for next start code */
2235         switch (start_code) {
2236         case SEQ_START_CODE:
2237             if (last_code == 0) {
2238                 mpeg1_decode_sequence(avctx, buf_ptr, input_size);
2239                 s->sync=1;
2240             } else {
2241                 av_log(avctx, AV_LOG_ERROR, "ignoring SEQ_START_CODE after %X\n", last_code);
2242                 if (avctx->err_recognition & AV_EF_EXPLODE)
2243                     return AVERROR_INVALIDDATA;
2244             }
2245             break;
2246
2247         case PICTURE_START_CODE:
2248             if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) && s->slice_count) {
2249                 int i;
2250
2251                 avctx->execute(avctx, slice_decode_thread,
2252                                s2->thread_context, NULL,
2253                                s->slice_count, sizeof(void*));
2254                 for (i = 0; i < s->slice_count; i++)
2255                     s2->error_count += s2->thread_context[i]->error_count;
2256                 s->slice_count = 0;
2257             }
2258             if (last_code == 0 || last_code == SLICE_MIN_START_CODE) {
2259                 ret = mpeg_decode_postinit(avctx);
2260                 if (ret < 0) {
2261                     av_log(avctx, AV_LOG_ERROR, "mpeg_decode_postinit() failure\n");
2262                     return ret;
2263                 }
2264
2265                 /* we have a complete image: we try to decompress it */
2266                 if (mpeg1_decode_picture(avctx, buf_ptr, input_size) < 0)
2267                     s2->pict_type = 0;
2268                 s2->first_slice = 1;
2269                 last_code = PICTURE_START_CODE;
2270             } else {
2271                 av_log(avctx, AV_LOG_ERROR, "ignoring pic after %X\n", last_code);
2272                 if (avctx->err_recognition & AV_EF_EXPLODE)
2273                     return AVERROR_INVALIDDATA;
2274             }
2275             break;
2276         case EXT_START_CODE:
2277             init_get_bits(&s2->gb, buf_ptr, input_size*8);
2278
2279             switch (get_bits(&s2->gb, 4)) {
2280             case 0x1:
2281                 if (last_code == 0) {
2282                 mpeg_decode_sequence_extension(s);
2283                 } else {
2284                     av_log(avctx, AV_LOG_ERROR, "ignoring seq ext after %X\n", last_code);
2285                     if (avctx->err_recognition & AV_EF_EXPLODE)
2286                         return AVERROR_INVALIDDATA;
2287                 }
2288                 break;
2289             case 0x2:
2290                 mpeg_decode_sequence_display_extension(s);
2291                 break;
2292             case 0x3:
2293                 mpeg_decode_quant_matrix_extension(s2);
2294                 break;
2295             case 0x7:
2296                 mpeg_decode_picture_display_extension(s);
2297                 break;
2298             case 0x8:
2299                 if (last_code == PICTURE_START_CODE) {
2300                     mpeg_decode_picture_coding_extension(s);
2301                 } else {
2302                     av_log(avctx, AV_LOG_ERROR, "ignoring pic cod ext after %X\n", last_code);
2303                     if (avctx->err_recognition & AV_EF_EXPLODE)
2304                         return AVERROR_INVALIDDATA;
2305                 }
2306                 break;
2307             }
2308             break;
2309         case USER_START_CODE:
2310             mpeg_decode_user_data(avctx, buf_ptr, input_size);
2311             break;
2312         case GOP_START_CODE:
2313             if (last_code == 0) {
2314                 s2->first_field=0;
2315                 mpeg_decode_gop(avctx, buf_ptr, input_size);
2316                 s->sync=1;
2317             } else {
2318                 av_log(avctx, AV_LOG_ERROR, "ignoring GOP_START_CODE after %X\n", last_code);
2319                 if (avctx->err_recognition & AV_EF_EXPLODE)
2320                     return AVERROR_INVALIDDATA;
2321             }
2322             break;
2323         default:
2324             if (start_code >= SLICE_MIN_START_CODE &&
2325                 start_code <= SLICE_MAX_START_CODE && last_code != 0) {
2326                 const int field_pic = s2->picture_structure != PICT_FRAME;
2327                 int mb_y = (start_code - SLICE_MIN_START_CODE) << field_pic;
2328                 last_code = SLICE_MIN_START_CODE;
2329
2330                 if (s2->picture_structure == PICT_BOTTOM_FIELD)
2331                     mb_y++;
2332
2333                 if (mb_y >= s2->mb_height) {
2334                     av_log(s2->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
2335                     return -1;
2336                 }
2337
2338                 if (s2->last_picture_ptr == NULL) {
2339                 /* Skip B-frames if we do not have reference frames and gop is not closed */
2340                     if (s2->pict_type == AV_PICTURE_TYPE_B) {
2341                         if (!s->closed_gop)
2342                             break;
2343                     }
2344                 }
2345                 if (s2->pict_type == AV_PICTURE_TYPE_I)
2346                     s->sync=1;
2347                 if (s2->next_picture_ptr == NULL) {
2348                 /* Skip P-frames if we do not have a reference frame or we have an invalid header. */
2349                     if (s2->pict_type == AV_PICTURE_TYPE_P && !s->sync) break;
2350                 }
2351                 if ((avctx->skip_frame >= AVDISCARD_NONREF && s2->pict_type == AV_PICTURE_TYPE_B) ||
2352                     (avctx->skip_frame >= AVDISCARD_NONKEY && s2->pict_type != AV_PICTURE_TYPE_I) ||
2353                      avctx->skip_frame >= AVDISCARD_ALL)
2354                     break;
2355
2356                 if (!s->mpeg_enc_ctx_allocated)
2357                     break;
2358
2359                 if (s2->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
2360                     if (mb_y < avctx->skip_top || mb_y >= s2->mb_height - avctx->skip_bottom)
2361                         break;
2362                 }
2363
2364                 if (!s2->pict_type) {
2365                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2366                     if (avctx->err_recognition & AV_EF_EXPLODE)
2367                         return AVERROR_INVALIDDATA;
2368                     break;
2369                 }
2370
2371                 if (s2->first_slice) {
2372                     s2->first_slice = 0;
2373                     if (mpeg_field_start(s2, buf, buf_size) < 0)
2374                         return -1;
2375                 }
2376                 if (!s2->current_picture_ptr) {
2377                     av_log(avctx, AV_LOG_ERROR, "current_picture not initialized\n");
2378                     return AVERROR_INVALIDDATA;
2379                 }
2380
2381                 if (avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU) {
2382                     s->slice_count++;
2383                     break;
2384                 }
2385
2386                 if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE)) {
2387                     int threshold = (s2->mb_height * s->slice_count +
2388                                      s2->slice_context_count / 2) /
2389                                     s2->slice_context_count;
2390                     if (threshold <= mb_y) {
2391                         MpegEncContext *thread_context = s2->thread_context[s->slice_count];
2392
2393                         thread_context->start_mb_y = mb_y;
2394                         thread_context->end_mb_y   = s2->mb_height;
2395                         if (s->slice_count) {
2396                             s2->thread_context[s->slice_count-1]->end_mb_y = mb_y;
2397                             ret = ff_update_duplicate_context(thread_context,
2398                                                               s2);
2399                             if (ret < 0)
2400                                 return ret;
2401                         }
2402                         init_get_bits(&thread_context->gb, buf_ptr, input_size*8);
2403                         s->slice_count++;
2404                     }
2405                     buf_ptr += 2; // FIXME add minimum number of bytes per slice
2406                 } else {
2407                     ret = mpeg_decode_slice(s2, mb_y, &buf_ptr, input_size);
2408                     emms_c();
2409
2410                     if (ret < 0) {
2411                         if (avctx->err_recognition & AV_EF_EXPLODE)
2412                             return ret;
2413                         if (s2->resync_mb_x >= 0 && s2->resync_mb_y >= 0)
2414                             ff_er_add_slice(s2, s2->resync_mb_x, s2->resync_mb_y, s2->mb_x, s2->mb_y, ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2415                     } else {
2416                         ff_er_add_slice(s2, s2->resync_mb_x, s2->resync_mb_y, s2->mb_x-1, s2->mb_y, ER_AC_END | ER_DC_END | ER_MV_END);
2417                     }
2418                 }
2419             }
2420             break;
2421         }
2422     }
2423 }
2424
2425 static int mpeg_decode_frame(AVCodecContext *avctx,
2426                              void *data, int *got_output,
2427                              AVPacket *avpkt)
2428 {
2429     const uint8_t *buf = avpkt->data;
2430     int buf_size = avpkt->size;
2431     Mpeg1Context *s = avctx->priv_data;
2432     AVFrame *picture = data;
2433     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2434     av_dlog(avctx, "fill_buffer\n");
2435
2436     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2437         /* special case for last picture */
2438         if (s2->low_delay == 0 && s2->next_picture_ptr) {
2439             *picture = s2->next_picture_ptr->f;
2440             s2->next_picture_ptr = NULL;
2441
2442             *got_output = 1;
2443         }
2444         return buf_size;
2445     }
2446
2447     if (s2->flags & CODEC_FLAG_TRUNCATED) {
2448         int next = ff_mpeg1_find_frame_end(&s2->parse_context, buf, buf_size, NULL);
2449
2450         if (ff_combine_frame(&s2->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0)
2451             return buf_size;
2452     }
2453
2454     if (s->mpeg_enc_ctx_allocated == 0 && avctx->codec_tag == AV_RL32("VCR2"))
2455         vcr2_init_sequence(avctx);
2456
2457     s->slice_count = 0;
2458
2459     if (avctx->extradata && !s->extradata_decoded) {
2460         int ret = decode_chunks(avctx, picture, got_output, avctx->extradata, avctx->extradata_size);
2461         s->extradata_decoded = 1;
2462         if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
2463             return ret;
2464     }
2465
2466     return decode_chunks(avctx, picture, got_output, buf, buf_size);
2467 }
2468
2469
2470 static void flush(AVCodecContext *avctx)
2471 {
2472     Mpeg1Context *s = avctx->priv_data;
2473
2474     s->sync=0;
2475     s->closed_gop = 0;
2476
2477     ff_mpeg_flush(avctx);
2478 }
2479
2480 static int mpeg_decode_end(AVCodecContext *avctx)
2481 {
2482     Mpeg1Context *s = avctx->priv_data;
2483
2484     if (s->mpeg_enc_ctx_allocated)
2485         ff_MPV_common_end(&s->mpeg_enc_ctx);
2486     return 0;
2487 }
2488
2489 static const AVProfile mpeg2_video_profiles[] = {
2490     { FF_PROFILE_MPEG2_422,          "4:2:2"              },
2491     { FF_PROFILE_MPEG2_HIGH,         "High"               },
2492     { FF_PROFILE_MPEG2_SS,           "Spatially Scalable" },
2493     { FF_PROFILE_MPEG2_SNR_SCALABLE, "SNR Scalable"       },
2494     { FF_PROFILE_MPEG2_MAIN,         "Main"               },
2495     { FF_PROFILE_MPEG2_SIMPLE,       "Simple"             },
2496     { FF_PROFILE_RESERVED,           "Reserved"           },
2497     { FF_PROFILE_RESERVED,           "Reserved"           },
2498     { FF_PROFILE_UNKNOWN },
2499 };
2500
2501
2502 AVCodec ff_mpeg1video_decoder = {
2503     .name                  = "mpeg1video",
2504     .type                  = AVMEDIA_TYPE_VIDEO,
2505     .id                    = AV_CODEC_ID_MPEG1VIDEO,
2506     .priv_data_size        = sizeof(Mpeg1Context),
2507     .init                  = mpeg_decode_init,
2508     .close                 = mpeg_decode_end,
2509     .decode                = mpeg_decode_frame,
2510     .capabilities          = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2511                              CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2512                              CODEC_CAP_SLICE_THREADS,
2513     .flush                 = flush,
2514     .long_name             = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2515     .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg_decode_update_thread_context)
2516 };
2517
2518 AVCodec ff_mpeg2video_decoder = {
2519     .name           = "mpeg2video",
2520     .type           = AVMEDIA_TYPE_VIDEO,
2521     .id             = AV_CODEC_ID_MPEG2VIDEO,
2522     .priv_data_size = sizeof(Mpeg1Context),
2523     .init           = mpeg_decode_init,
2524     .close          = mpeg_decode_end,
2525     .decode         = mpeg_decode_frame,
2526     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2527                       CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2528                       CODEC_CAP_SLICE_THREADS,
2529     .flush          = flush,
2530     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2531     .profiles       = NULL_IF_CONFIG_SMALL(mpeg2_video_profiles),
2532 };
2533
2534 #if CONFIG_MPEG_XVMC_DECODER
2535 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx)
2536 {
2537     if (avctx->active_thread_type & FF_THREAD_SLICE)
2538         return -1;
2539     if (!(avctx->slice_flags & SLICE_FLAG_CODED_ORDER))
2540         return -1;
2541     if (!(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
2542         av_dlog(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2543     }
2544     mpeg_decode_init(avctx);
2545
2546     avctx->pix_fmt           = AV_PIX_FMT_XVMC_MPEG2_IDCT;
2547     avctx->xvmc_acceleration = 2; // 2 - the blocks are packed!
2548
2549     return 0;
2550 }
2551
2552 AVCodec ff_mpeg_xvmc_decoder = {
2553     .name           = "mpegvideo_xvmc",
2554     .type           = AVMEDIA_TYPE_VIDEO,
2555     .id             = AV_CODEC_ID_MPEG2VIDEO_XVMC,
2556     .priv_data_size = sizeof(Mpeg1Context),
2557     .init           = mpeg_mc_decode_init,
2558     .close          = mpeg_decode_end,
2559     .decode         = mpeg_decode_frame,
2560     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2561                       CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
2562     .flush          = flush,
2563     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
2564 };
2565
2566 #endif
2567
2568 #if CONFIG_MPEG_VDPAU_DECODER
2569 AVCodec ff_mpeg_vdpau_decoder = {
2570     .name           = "mpegvideo_vdpau",
2571     .type           = AVMEDIA_TYPE_VIDEO,
2572     .id             = AV_CODEC_ID_MPEG2VIDEO,
2573     .priv_data_size = sizeof(Mpeg1Context),
2574     .init           = mpeg_decode_init,
2575     .close          = mpeg_decode_end,
2576     .decode         = mpeg_decode_frame,
2577     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED |
2578                       CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2579     .flush          = flush,
2580     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
2581 };
2582 #endif
2583
2584 #if CONFIG_MPEG1_VDPAU_DECODER
2585 AVCodec ff_mpeg1_vdpau_decoder = {
2586     .name           = "mpeg1video_vdpau",
2587     .type           = AVMEDIA_TYPE_VIDEO,
2588     .id             = AV_CODEC_ID_MPEG1VIDEO,
2589     .priv_data_size = sizeof(Mpeg1Context),
2590     .init           = mpeg_decode_init,
2591     .close          = mpeg_decode_end,
2592     .decode         = mpeg_decode_frame,
2593     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED |
2594                       CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2595     .flush          = flush,
2596     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
2597 };
2598 #endif