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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 #include <inttypes.h>
  29
  30 #include "libavutil/attributes.h"
  31 #include "libavutil/internal.h"
  32 #include "libavutil/stereo3d.h"
  33
  34 #include "avcodec.h"
  35 #include "bytestream.h"
  36 #include "error_resilience.h"
  37 #include "idctdsp.h"
  38 #include "internal.h"
  39 #include "mpeg_er.h"
  40 #include "mpeg12.h"
  41 #include "mpeg12data.h"
  42 #include "mpegutils.h"
  43 #include "mpegvideo.h"
  44 #include "thread.h"
  45 #include "version.h"
  46 #include "xvmc_internal.h"
  47
  48 typedef struct Mpeg1Context {
  49     MpegEncContext mpeg_enc_ctx;
  50     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
  51     int repeat_field;           /* true if we must repeat the field */
  52     AVPanScan pan_scan;         /* some temporary storage for the panscan */
  53     AVStereo3D stereo3d;
  54     int has_stereo3d;
  55     uint8_t *a53_caption;
  56     int a53_caption_size;
  57     uint8_t afd;
  58     int has_afd;
  59     int slice_count;
  60     int save_aspect_info;
  61     int save_width, save_height, save_progressive_seq;
  62     AVRational frame_rate_ext;  /* MPEG-2 specific framerate modificator */
  63     int sync;                   /* Did we reach a sync point like a GOP/SEQ/KEYFrame? */
  64     int closed_gop;             /* GOP is closed */
  65     int first_slice;
  66     int extradata_decoded;
  67 } Mpeg1Context;
  68
  69 #define MB_TYPE_ZERO_MV   0x20000000
  70
  71 static const uint32_t ptype2mb_type[7] = {
  72                     MB_TYPE_INTRA,
  73                     MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
  74                     MB_TYPE_L0,
  75                     MB_TYPE_L0 | MB_TYPE_CBP,
  76     MB_TYPE_QUANT | MB_TYPE_INTRA,
  77     MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
  78     MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP,
  79 };
  80
  81 static const uint32_t btype2mb_type[11] = {
  82                     MB_TYPE_INTRA,
  83                     MB_TYPE_L1,
  84                     MB_TYPE_L1   | MB_TYPE_CBP,
  85                     MB_TYPE_L0,
  86                     MB_TYPE_L0   | MB_TYPE_CBP,
  87                     MB_TYPE_L0L1,
  88                     MB_TYPE_L0L1 | MB_TYPE_CBP,
  89     MB_TYPE_QUANT | MB_TYPE_INTRA,
  90     MB_TYPE_QUANT | MB_TYPE_L1   | MB_TYPE_CBP,
  91     MB_TYPE_QUANT | MB_TYPE_L0   | MB_TYPE_CBP,
  92     MB_TYPE_QUANT | MB_TYPE_L0L1 | MB_TYPE_CBP,
  93 };
  94
  95 static const uint8_t non_linear_qscale[32] = {
  96      0,  1,  2,  3,  4,  5,   6,   7,
  97      8, 10, 12, 14, 16, 18,  20,  22,
  98     24, 28, 32, 36, 40, 44,  48,  52,
  99     56, 64, 72, 80, 88, 96, 104, 112,
 100 };
 101
 102 /* as H.263, but only 17 codes */
 103 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
 104 {
 105     int code, sign, val, shift;
 106
 107     code = get_vlc2(&s->gb, ff_mv_vlc.table, MV_VLC_BITS, 2);
 108     if (code == 0)
 109         return pred;
 110     if (code < 0)
 111         return 0xffff;
 112
 113     sign  = get_bits1(&s->gb);
 114     shift = fcode - 1;
 115     val   = code;
 116     if (shift) {
 117         val  = (val - 1) << shift;
 118         val |= get_bits(&s->gb, shift);
 119         val++;
 120     }
 121     if (sign)
 122         val = -val;
 123     val += pred;
 124
 125     /* modulo decoding */
 126     return sign_extend(val, 5 + shift);
 127 }
 128
 129 #define check_scantable_index(ctx, x)                                         \
 130     do {                                                                      \
 131         if ((x) > 63) {                                                       \
 132             av_log(ctx->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n",     \
 133                    ctx->mb_x, ctx->mb_y);                                     \
 134             return AVERROR_INVALIDDATA;                                       \
 135         }                                                                     \
 136     } while (0)
 137
 138 static inline int mpeg1_decode_block_intra(MpegEncContext *s,
 139                                            int16_t *block, int n)
 140 {
 141     int level, dc, diff, i, j, run;
 142     int component;
 143     RLTable *rl                  = &ff_rl_mpeg1;
 144     uint8_t *const scantable     = s->intra_scantable.permutated;
 145     const uint16_t *quant_matrix = s->intra_matrix;
 146     const int qscale             = s->qscale;
 147
 148     /* DC coefficient */
 149     component = (n <= 3 ? 0 : n - 4 + 1);
 150     diff = decode_dc(&s->gb, component);
 151     if (diff >= 0xffff)
 152         return -1;
 153     dc  = s->last_dc[component];
 154     dc += diff;
 155     s->last_dc[component] = dc;
 156     block[0] = dc * quant_matrix[0];
 157     av_dlog(s->avctx, "dc=%d diff=%d\n", dc, diff);
 158     i = 0;
 159     {
 160         OPEN_READER(re, &s->gb);
 161         /* now quantify & encode AC coefficients */
 162         for (;;) {
 163             UPDATE_CACHE(re, &s->gb);
 164             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 165                        TEX_VLC_BITS, 2, 0);
 166
 167             if (level == 127) {
 168                 break;
 169             } else if (level != 0) {
 170                 i += run;
 171                 check_scantable_index(s, i);
 172                 j = scantable[i];
 173                 level = (level * qscale * quant_matrix[j]) >> 4;
 174                 level = (level - 1) | 1;
 175                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 176                         SHOW_SBITS(re, &s->gb, 1);
 177                 LAST_SKIP_BITS(re, &s->gb, 1);
 178             } else {
 179                 /* escape */
 180                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 181                 LAST_SKIP_BITS(re, &s->gb, 6);
 182                 UPDATE_CACHE(re, &s->gb);
 183                 level = SHOW_SBITS(re, &s->gb, 8);
 184                 SKIP_BITS(re, &s->gb, 8);
 185                 if (level == -128) {
 186                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
 187                     LAST_SKIP_BITS(re, &s->gb, 8);
 188                 } else if (level == 0) {
 189                     level = SHOW_UBITS(re, &s->gb, 8);
 190                     LAST_SKIP_BITS(re, &s->gb, 8);
 191                 }
 192                 i += run;
 193                 check_scantable_index(s, i);
 194                 j = scantable[i];
 195                 if (level < 0) {
 196                     level = -level;
 197                     level = (level * qscale * quant_matrix[j]) >> 4;
 198                     level = (level - 1) | 1;
 199                     level = -level;
 200                 } else {
 201                     level = (level * qscale * quant_matrix[j]) >> 4;
 202                     level = (level - 1) | 1;
 203                 }
 204             }
 205
 206             block[j] = level;
 207         }
 208         CLOSE_READER(re, &s->gb);
 209     }
 210     s->block_last_index[n] = i;
 211     return 0;
 212 }
 213
 214 int ff_mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
 215 {
 216     return mpeg1_decode_block_intra(s, block, n);
 217 }
 218
 219 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
 220                                            int16_t *block, int n)
 221 {
 222     int level, i, j, run;
 223     RLTable *rl                  = &ff_rl_mpeg1;
 224     uint8_t *const scantable     = s->intra_scantable.permutated;
 225     const uint16_t *quant_matrix = s->inter_matrix;
 226     const int qscale             = s->qscale;
 227
 228     {
 229         OPEN_READER(re, &s->gb);
 230         i = -1;
 231         // special case for first coefficient, no need to add second VLC table
 232         UPDATE_CACHE(re, &s->gb);
 233         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 234             level = (3 * qscale * quant_matrix[0]) >> 5;
 235             level = (level - 1) | 1;
 236             if (GET_CACHE(re, &s->gb) & 0x40000000)
 237                 level = -level;
 238             block[0] = level;
 239             i++;
 240             SKIP_BITS(re, &s->gb, 2);
 241             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 242                 goto end;
 243         }
 244         /* now quantify & encode AC coefficients */
 245         for (;;) {
 246             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 247                        TEX_VLC_BITS, 2, 0);
 248
 249             if (level != 0) {
 250                 i += run;
 251                 check_scantable_index(s, i);
 252                 j = scantable[i];
 253                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 254                 level = (level - 1) | 1;
 255                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 256                         SHOW_SBITS(re, &s->gb, 1);
 257                 SKIP_BITS(re, &s->gb, 1);
 258             } else {
 259                 /* escape */
 260                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 261                 LAST_SKIP_BITS(re, &s->gb, 6);
 262                 UPDATE_CACHE(re, &s->gb);
 263                 level = SHOW_SBITS(re, &s->gb, 8);
 264                 SKIP_BITS(re, &s->gb, 8);
 265                 if (level == -128) {
 266                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
 267                     SKIP_BITS(re, &s->gb, 8);
 268                 } else if (level == 0) {
 269                     level = SHOW_UBITS(re, &s->gb, 8);
 270                     SKIP_BITS(re, &s->gb, 8);
 271                 }
 272                 i += run;
 273                 check_scantable_index(s, i);
 274                 j = scantable[i];
 275                 if (level < 0) {
 276                     level = -level;
 277                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 278                     level = (level - 1) | 1;
 279                     level = -level;
 280                 } else {
 281                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 282                     level = (level - 1) | 1;
 283                 }
 284             }
 285
 286             block[j] = level;
 287             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 288                 break;
 289             UPDATE_CACHE(re, &s->gb);
 290         }
 291 end:
 292         LAST_SKIP_BITS(re, &s->gb, 2);
 293         CLOSE_READER(re, &s->gb);
 294     }
 295     s->block_last_index[n] = i;
 296     return 0;
 297 }
 298
 299 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s,
 300                                                 int16_t *block, int n)
 301 {
 302     int level, i, j, run;
 303     RLTable *rl              = &ff_rl_mpeg1;
 304     uint8_t *const scantable = s->intra_scantable.permutated;
 305     const int qscale         = s->qscale;
 306
 307     {
 308         OPEN_READER(re, &s->gb);
 309         i = -1;
 310         // Special case for first coefficient, no need to add second VLC table.
 311         UPDATE_CACHE(re, &s->gb);
 312         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 313             level = (3 * qscale) >> 1;
 314             level = (level - 1) | 1;
 315             if (GET_CACHE(re, &s->gb) & 0x40000000)
 316                 level = -level;
 317             block[0] = level;
 318             i++;
 319             SKIP_BITS(re, &s->gb, 2);
 320             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 321                 goto end;
 322         }
 323
 324         /* now quantify & encode AC coefficients */
 325         for (;;) {
 326             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 327                        TEX_VLC_BITS, 2, 0);
 328
 329             if (level != 0) {
 330                 i += run;
 331                 check_scantable_index(s, i);
 332                 j = scantable[i];
 333                 level = ((level * 2 + 1) * qscale) >> 1;
 334                 level = (level - 1) | 1;
 335                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 336                         SHOW_SBITS(re, &s->gb, 1);
 337                 SKIP_BITS(re, &s->gb, 1);
 338             } else {
 339                 /* escape */
 340                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 341                 LAST_SKIP_BITS(re, &s->gb, 6);
 342                 UPDATE_CACHE(re, &s->gb);
 343                 level = SHOW_SBITS(re, &s->gb, 8);
 344                 SKIP_BITS(re, &s->gb, 8);
 345                 if (level == -128) {
 346                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
 347                     SKIP_BITS(re, &s->gb, 8);
 348                 } else if (level == 0) {
 349                     level = SHOW_UBITS(re, &s->gb, 8);
 350                     SKIP_BITS(re, &s->gb, 8);
 351                 }
 352                 i += run;
 353                 check_scantable_index(s, i);
 354                 j = scantable[i];
 355                 if (level < 0) {
 356                     level = -level;
 357                     level = ((level * 2 + 1) * qscale) >> 1;
 358                     level = (level - 1) | 1;
 359                     level = -level;
 360                 } else {
 361                     level = ((level * 2 + 1) * qscale) >> 1;
 362                     level = (level - 1) | 1;
 363                 }
 364             }
 365
 366             block[j] = level;
 367             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 368                 break;
 369             UPDATE_CACHE(re, &s->gb);
 370         }
 371 end:
 372         LAST_SKIP_BITS(re, &s->gb, 2);
 373         CLOSE_READER(re, &s->gb);
 374     }
 375     s->block_last_index[n] = i;
 376     return 0;
 377 }
 378
 379 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
 380                                                int16_t *block, int n)
 381 {
 382     int level, i, j, run;
 383     RLTable *rl = &ff_rl_mpeg1;
 384     uint8_t *const scantable = s->intra_scantable.permutated;
 385     const uint16_t *quant_matrix;
 386     const int qscale = s->qscale;
 387     int mismatch;
 388
 389     mismatch = 1;
 390
 391     {
 392         OPEN_READER(re, &s->gb);
 393         i = -1;
 394         if (n < 4)
 395             quant_matrix = s->inter_matrix;
 396         else
 397             quant_matrix = s->chroma_inter_matrix;
 398
 399         // Special case for first coefficient, no need to add second VLC table.
 400         UPDATE_CACHE(re, &s->gb);
 401         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 402             level = (3 * qscale * quant_matrix[0]) >> 5;
 403             if (GET_CACHE(re, &s->gb) & 0x40000000)
 404                 level = -level;
 405             block[0]  = level;
 406             mismatch ^= level;
 407             i++;
 408             SKIP_BITS(re, &s->gb, 2);
 409             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 410                 goto end;
 411         }
 412
 413         /* now quantify & encode AC coefficients */
 414         for (;;) {
 415             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 416                        TEX_VLC_BITS, 2, 0);
 417
 418             if (level != 0) {
 419                 i += run;
 420                 check_scantable_index(s, i);
 421                 j = scantable[i];
 422                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 423                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 424                         SHOW_SBITS(re, &s->gb, 1);
 425                 SKIP_BITS(re, &s->gb, 1);
 426             } else {
 427                 /* escape */
 428                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 429                 LAST_SKIP_BITS(re, &s->gb, 6);
 430                 UPDATE_CACHE(re, &s->gb);
 431                 level = SHOW_SBITS(re, &s->gb, 12);
 432                 SKIP_BITS(re, &s->gb, 12);
 433
 434                 i += run;
 435                 check_scantable_index(s, i);
 436                 j = scantable[i];
 437                 if (level < 0) {
 438                     level = ((-level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 439                     level = -level;
 440                 } else {
 441                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 442                 }
 443             }
 444
 445             mismatch ^= level;
 446             block[j]  = level;
 447             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 448                 break;
 449             UPDATE_CACHE(re, &s->gb);
 450         }
 451 end:
 452         LAST_SKIP_BITS(re, &s->gb, 2);
 453         CLOSE_READER(re, &s->gb);
 454     }
 455     block[63] ^= (mismatch & 1);
 456
 457     s->block_last_index[n] = i;
 458     return 0;
 459 }
 460
 461 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
 462                                                     int16_t *block, int n)
 463 {
 464     int level, i, j, run;
 465     RLTable *rl              = &ff_rl_mpeg1;
 466     uint8_t *const scantable = s->intra_scantable.permutated;
 467     const int qscale         = s->qscale;
 468     OPEN_READER(re, &s->gb);
 469     i = -1;
 470
 471     // special case for first coefficient, no need to add second VLC table
 472     UPDATE_CACHE(re, &s->gb);
 473     if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 474         level = (3 * qscale) >> 1;
 475         if (GET_CACHE(re, &s->gb) & 0x40000000)
 476             level = -level;
 477         block[0] = level;
 478         i++;
 479         SKIP_BITS(re, &s->gb, 2);
 480         if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 481             goto end;
 482     }
 483
 484     /* now quantify & encode AC coefficients */
 485     for (;;) {
 486         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 487
 488         if (level != 0) {
 489             i += run;
 490             check_scantable_index(s, i);
 491             j = scantable[i];
 492             level = ((level * 2 + 1) * qscale) >> 1;
 493             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 494                     SHOW_SBITS(re, &s->gb, 1);
 495             SKIP_BITS(re, &s->gb, 1);
 496         } else {
 497             /* escape */
 498             run = SHOW_UBITS(re, &s->gb, 6) + 1;
 499             LAST_SKIP_BITS(re, &s->gb, 6);
 500             UPDATE_CACHE(re, &s->gb);
 501             level = SHOW_SBITS(re, &s->gb, 12);
 502             SKIP_BITS(re, &s->gb, 12);
 503
 504             i += run;
 505             check_scantable_index(s, i);
 506             j = scantable[i];
 507             if (level < 0) {
 508                 level = ((-level * 2 + 1) * qscale) >> 1;
 509                 level = -level;
 510             } else {
 511                 level = ((level * 2 + 1) * qscale) >> 1;
 512             }
 513         }
 514
 515         block[j] = level;
 516         if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 517             break;
 518         UPDATE_CACHE(re, &s->gb);
 519     }
 520 end:
 521     LAST_SKIP_BITS(re, &s->gb, 2);
 522     CLOSE_READER(re, &s->gb);
 523     s->block_last_index[n] = i;
 524     return 0;
 525 }
 526
 527 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
 528                                            int16_t *block, int n)
 529 {
 530     int level, dc, diff, i, j, run;
 531     int component;
 532     RLTable *rl;
 533     uint8_t *const scantable = s->intra_scantable.permutated;
 534     const uint16_t *quant_matrix;
 535     const int qscale = s->qscale;
 536     int mismatch;
 537
 538     /* DC coefficient */
 539     if (n < 4) {
 540         quant_matrix = s->intra_matrix;
 541         component    = 0;
 542     } else {
 543         quant_matrix = s->chroma_intra_matrix;
 544         component    = (n & 1) + 1;
 545     }
 546     diff = decode_dc(&s->gb, component);
 547     if (diff >= 0xffff)
 548         return -1;
 549     dc  = s->last_dc[component];
 550     dc += diff;
 551     s->last_dc[component] = dc;
 552     block[0] = dc << (3 - s->intra_dc_precision);
 553     av_dlog(s->avctx, "dc=%d\n", block[0]);
 554     mismatch = block[0] ^ 1;
 555     i = 0;
 556     if (s->intra_vlc_format)
 557         rl = &ff_rl_mpeg2;
 558     else
 559         rl = &ff_rl_mpeg1;
 560
 561     {
 562         OPEN_READER(re, &s->gb);
 563         /* now quantify & encode AC coefficients */
 564         for (;;) {
 565             UPDATE_CACHE(re, &s->gb);
 566             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 567                        TEX_VLC_BITS, 2, 0);
 568
 569             if (level == 127) {
 570                 break;
 571             } else if (level != 0) {
 572                 i += run;
 573                 check_scantable_index(s, i);
 574                 j = scantable[i];
 575                 level = (level * qscale * quant_matrix[j]) >> 4;
 576                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 577                         SHOW_SBITS(re, &s->gb, 1);
 578                 LAST_SKIP_BITS(re, &s->gb, 1);
 579             } else {
 580                 /* escape */
 581                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 582                 LAST_SKIP_BITS(re, &s->gb, 6);
 583                 UPDATE_CACHE(re, &s->gb);
 584                 level = SHOW_SBITS(re, &s->gb, 12);
 585                 SKIP_BITS(re, &s->gb, 12);
 586                 i += run;
 587                 check_scantable_index(s, i);
 588                 j = scantable[i];
 589                 if (level < 0) {
 590                     level = (-level * qscale * quant_matrix[j]) >> 4;
 591                     level = -level;
 592                 } else {
 593                     level = (level * qscale * quant_matrix[j]) >> 4;
 594                 }
 595             }
 596
 597             mismatch ^= level;
 598             block[j]  = level;
 599         }
 600         CLOSE_READER(re, &s->gb);
 601     }
 602     block[63] ^= mismatch & 1;
 603
 604     s->block_last_index[n] = i;
 605     return 0;
 606 }
 607
 608 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
 609                                                 int16_t *block, int n)
 610 {
 611     int level, dc, diff, i, j, run;
 612     int component;
 613     RLTable *rl;
 614     uint8_t *const scantable = s->intra_scantable.permutated;
 615     const uint16_t *quant_matrix;
 616     const int qscale = s->qscale;
 617
 618     /* DC coefficient */
 619     if (n < 4) {
 620         quant_matrix = s->intra_matrix;
 621         component    = 0;
 622     } else {
 623         quant_matrix = s->chroma_intra_matrix;
 624         component    = (n & 1) + 1;
 625     }
 626     diff = decode_dc(&s->gb, component);
 627     if (diff >= 0xffff)
 628         return -1;
 629     dc = s->last_dc[component];
 630     dc += diff;
 631     s->last_dc[component] = dc;
 632     block[0] = dc << (3 - s->intra_dc_precision);
 633     i = 0;
 634     if (s->intra_vlc_format)
 635         rl = &ff_rl_mpeg2;
 636     else
 637         rl = &ff_rl_mpeg1;
 638
 639     {
 640         OPEN_READER(re, &s->gb);
 641         /* now quantify & encode AC coefficients */
 642         for (;;) {
 643             UPDATE_CACHE(re, &s->gb);
 644             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 645                        TEX_VLC_BITS, 2, 0);
 646
 647             if (level == 127) {
 648                 break;
 649             } else if (level != 0) {
 650                 i += run;
 651                 check_scantable_index(s, i);
 652                 j = scantable[i];
 653                 level = (level * qscale * quant_matrix[j]) >> 4;
 654                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 655                         SHOW_SBITS(re, &s->gb, 1);
 656                 LAST_SKIP_BITS(re, &s->gb, 1);
 657             } else {
 658                 /* escape */
 659                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 660                 LAST_SKIP_BITS(re, &s->gb, 6);
 661                 UPDATE_CACHE(re, &s->gb);
 662                 level = SHOW_SBITS(re, &s->gb, 12);
 663                 SKIP_BITS(re, &s->gb, 12);
 664                 i += run;
 665                 check_scantable_index(s, i);
 666                 j = scantable[i];
 667                 if (level < 0) {
 668                     level = (-level * qscale * quant_matrix[j]) >> 4;
 669                     level = -level;
 670                 } else {
 671                     level = (level * qscale * quant_matrix[j]) >> 4;
 672                 }
 673             }
 674
 675             block[j] = level;
 676         }
 677         CLOSE_READER(re, &s->gb);
 678     }
 679
 680     s->block_last_index[n] = i;
 681     return 0;
 682 }
 683
 684 /******************************************/
 685 /* decoding */
 686
 687 static inline int get_dmv(MpegEncContext *s)
 688 {
 689     if (get_bits1(&s->gb))
 690         return 1 - (get_bits1(&s->gb) << 1);
 691     else
 692         return 0;
 693 }
 694
 695 static inline int get_qscale(MpegEncContext *s)
 696 {
 697     int qscale = get_bits(&s->gb, 5);
 698     if (s->q_scale_type)
 699         return non_linear_qscale[qscale];
 700     else
 701         return qscale << 1;
 702 }
 703
 704 /* motion type (for MPEG-2) */
 705 #define MT_FIELD 1
 706 #define MT_FRAME 2
 707 #define MT_16X8  2
 708 #define MT_DMV   3
 709
 710 static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
 711 {
 712     int i, j, k, cbp, val, mb_type, motion_type;
 713     const int mb_block_count = 4 + (1 << s->chroma_format);
 714
 715     av_dlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
 716
 717     assert(s->mb_skipped == 0);
 718
 719     if (s->mb_skip_run-- != 0) {
 720         if (s->pict_type == AV_PICTURE_TYPE_P) {
 721             s->mb_skipped = 1;
 722             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
 723                 MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 724         } else {
 725             int mb_type;
 726
 727             if (s->mb_x)
 728                 mb_type = s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1];
 729             else
 730                 // FIXME not sure if this is allowed in MPEG at all
 731                 mb_type = s->current_picture.mb_type[s->mb_width + (s->mb_y - 1) * s->mb_stride - 1];
 732             if (IS_INTRA(mb_type))
 733                 return -1;
 734             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
 735                 mb_type | MB_TYPE_SKIP;
 736 //            assert(s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1] & (MB_TYPE_16x16 | MB_TYPE_16x8));
 737
 738             if ((s->mv[0][0][0] | s->mv[0][0][1] | s->mv[1][0][0] | s->mv[1][0][1]) == 0)
 739                 s->mb_skipped = 1;
 740         }
 741
 742         return 0;
 743     }
 744
 745     switch (s->pict_type) {
 746     default:
 747     case AV_PICTURE_TYPE_I:
 748         if (get_bits1(&s->gb) == 0) {
 749             if (get_bits1(&s->gb) == 0) {
 750                 av_log(s->avctx, AV_LOG_ERROR,
 751                        "invalid mb type in I Frame at %d %d\n",
 752                        s->mb_x, s->mb_y);
 753                 return -1;
 754             }
 755             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
 756         } else {
 757             mb_type = MB_TYPE_INTRA;
 758         }
 759         break;
 760     case AV_PICTURE_TYPE_P:
 761         mb_type = get_vlc2(&s->gb, ff_mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
 762         if (mb_type < 0) {
 763             av_log(s->avctx, AV_LOG_ERROR,
 764                    "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
 765             return -1;
 766         }
 767         mb_type = ptype2mb_type[mb_type];
 768         break;
 769     case AV_PICTURE_TYPE_B:
 770         mb_type = get_vlc2(&s->gb, ff_mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
 771         if (mb_type < 0) {
 772             av_log(s->avctx, AV_LOG_ERROR,
 773                    "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
 774             return -1;
 775         }
 776         mb_type = btype2mb_type[mb_type];
 777         break;
 778     }
 779     av_dlog(s->avctx, "mb_type=%x\n", mb_type);
 780 //    motion_type = 0; /* avoid warning */
 781     if (IS_INTRA(mb_type)) {
 782         s->bdsp.clear_blocks(s->block[0]);
 783
 784         if (!s->chroma_y_shift)
 785             s->bdsp.clear_blocks(s->block[6]);
 786
 787         /* compute DCT type */
 788         // FIXME: add an interlaced_dct coded var?
 789         if (s->picture_structure == PICT_FRAME &&
 790             !s->frame_pred_frame_dct)
 791             s->interlaced_dct = get_bits1(&s->gb);
 792
 793         if (IS_QUANT(mb_type))
 794             s->qscale = get_qscale(s);
 795
 796         if (s->concealment_motion_vectors) {
 797             /* just parse them */
 798             if (s->picture_structure != PICT_FRAME)
 799                 skip_bits1(&s->gb);  /* field select */
 800
 801             s->mv[0][0][0]      =
 802             s->last_mv[0][0][0] =
 803             s->last_mv[0][1][0] = mpeg_decode_motion(s, s->mpeg_f_code[0][0],
 804                                                      s->last_mv[0][0][0]);
 805             s->mv[0][0][1]      =
 806             s->last_mv[0][0][1] =
 807             s->last_mv[0][1][1] = mpeg_decode_motion(s, s->mpeg_f_code[0][1],
 808                                                      s->last_mv[0][0][1]);
 809
 810             skip_bits1(&s->gb); /* marker */
 811         } else {
 812             /* reset mv prediction */
 813             memset(s->last_mv, 0, sizeof(s->last_mv));
 814         }
 815         s->mb_intra = 1;
 816 #if FF_API_XVMC
 817 FF_DISABLE_DEPRECATION_WARNINGS
 818         // if 1, we memcpy blocks in xvmcvideo
 819         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
 820             ff_xvmc_pack_pblocks(s, -1); // inter are always full blocks
 821 FF_ENABLE_DEPRECATION_WARNINGS
 822 #endif /* FF_API_XVMC */
 823
 824         if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
 825             if (s->flags2 & CODEC_FLAG2_FAST) {
 826                 for (i = 0; i < 6; i++)
 827                     mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
 828             } else {
 829                 for (i = 0; i < mb_block_count; i++)
 830                     if (mpeg2_decode_block_intra(s, *s->pblocks[i], i) < 0)
 831                         return -1;
 832             }
 833         } else {
 834             for (i = 0; i < 6; i++)
 835                 if (mpeg1_decode_block_intra(s, *s->pblocks[i], i) < 0)
 836                     return -1;
 837         }
 838     } else {
 839         if (mb_type & MB_TYPE_ZERO_MV) {
 840             assert(mb_type & MB_TYPE_CBP);
 841
 842             s->mv_dir = MV_DIR_FORWARD;
 843             if (s->picture_structure == PICT_FRAME) {
 844                 if (!s->frame_pred_frame_dct)
 845                     s->interlaced_dct = get_bits1(&s->gb);
 846                 s->mv_type = MV_TYPE_16X16;
 847             } else {
 848                 s->mv_type            = MV_TYPE_FIELD;
 849                 mb_type              |= MB_TYPE_INTERLACED;
 850                 s->field_select[0][0] = s->picture_structure - 1;
 851             }
 852
 853             if (IS_QUANT(mb_type))
 854                 s->qscale = get_qscale(s);
 855
 856             s->last_mv[0][0][0] = 0;
 857             s->last_mv[0][0][1] = 0;
 858             s->last_mv[0][1][0] = 0;
 859             s->last_mv[0][1][1] = 0;
 860             s->mv[0][0][0]      = 0;
 861             s->mv[0][0][1]      = 0;
 862         } else {
 863             assert(mb_type & MB_TYPE_L0L1);
 864             // FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
 865             /* get additional motion vector type */
 866             if (s->frame_pred_frame_dct) {
 867                 motion_type = MT_FRAME;
 868             } else {
 869                 motion_type = get_bits(&s->gb, 2);
 870                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
 871                     s->interlaced_dct = get_bits1(&s->gb);
 872             }
 873
 874             if (IS_QUANT(mb_type))
 875                 s->qscale = get_qscale(s);
 876
 877             /* motion vectors */
 878             s->mv_dir = (mb_type >> 13) & 3;
 879             av_dlog(s->avctx, "motion_type=%d\n", motion_type);
 880             switch (motion_type) {
 881             case MT_FRAME: /* or MT_16X8 */
 882                 if (s->picture_structure == PICT_FRAME) {
 883                     mb_type   |= MB_TYPE_16x16;
 884                     s->mv_type = MV_TYPE_16X16;
 885                     for (i = 0; i < 2; i++) {
 886                         if (USES_LIST(mb_type, i)) {
 887                             /* MT_FRAME */
 888                             s->mv[i][0][0]      =
 889                             s->last_mv[i][0][0] =
 890                             s->last_mv[i][1][0] =
 891                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 892                                                    s->last_mv[i][0][0]);
 893                             s->mv[i][0][1]      =
 894                             s->last_mv[i][0][1] =
 895                             s->last_mv[i][1][1] =
 896                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 897                                                    s->last_mv[i][0][1]);
 898                             /* full_pel: only for MPEG-1 */
 899                             if (s->full_pel[i]) {
 900                                 s->mv[i][0][0] <<= 1;
 901                                 s->mv[i][0][1] <<= 1;
 902                             }
 903                         }
 904                     }
 905                 } else {
 906                     mb_type   |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 907                     s->mv_type = MV_TYPE_16X8;
 908                     for (i = 0; i < 2; i++) {
 909                         if (USES_LIST(mb_type, i)) {
 910                             /* MT_16X8 */
 911                             for (j = 0; j < 2; j++) {
 912                                 s->field_select[i][j] = get_bits1(&s->gb);
 913                                 for (k = 0; k < 2; k++) {
 914                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 915                                                              s->last_mv[i][j][k]);
 916                                     s->last_mv[i][j][k] = val;
 917                                     s->mv[i][j][k]      = val;
 918                                 }
 919                             }
 920                         }
 921                     }
 922                 }
 923                 break;
 924             case MT_FIELD:
 925                 s->mv_type = MV_TYPE_FIELD;
 926                 if (s->picture_structure == PICT_FRAME) {
 927                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 928                     for (i = 0; i < 2; i++) {
 929                         if (USES_LIST(mb_type, i)) {
 930                             for (j = 0; j < 2; j++) {
 931                                 s->field_select[i][j] = get_bits1(&s->gb);
 932                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 933                                                          s->last_mv[i][j][0]);
 934                                 s->last_mv[i][j][0] = val;
 935                                 s->mv[i][j][0]      = val;
 936                                 av_dlog(s->avctx, "fmx=%d\n", val);
 937                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 938                                                          s->last_mv[i][j][1] >> 1);
 939                                 s->last_mv[i][j][1] = val << 1;
 940                                 s->mv[i][j][1]      = val;
 941                                 av_dlog(s->avctx, "fmy=%d\n", val);
 942                             }
 943                         }
 944                     }
 945                 } else {
 946                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 947                     for (i = 0; i < 2; i++) {
 948                         if (USES_LIST(mb_type, i)) {
 949                             s->field_select[i][0] = get_bits1(&s->gb);
 950                             for (k = 0; k < 2; k++) {
 951                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 952                                                          s->last_mv[i][0][k]);
 953                                 s->last_mv[i][0][k] = val;
 954                                 s->last_mv[i][1][k] = val;
 955                                 s->mv[i][0][k]      = val;
 956                             }
 957                         }
 958                     }
 959                 }
 960                 break;
 961             case MT_DMV:
 962                 s->mv_type = MV_TYPE_DMV;
 963                 for (i = 0; i < 2; i++) {
 964                     if (USES_LIST(mb_type, i)) {
 965                         int dmx, dmy, mx, my, m;
 966                         const int my_shift = s->picture_structure == PICT_FRAME;
 967
 968                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 969                                                 s->last_mv[i][0][0]);
 970                         s->last_mv[i][0][0] = mx;
 971                         s->last_mv[i][1][0] = mx;
 972                         dmx = get_dmv(s);
 973                         my  = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 974                                                  s->last_mv[i][0][1] >> my_shift);
 975                         dmy = get_dmv(s);
 976
 977
 978                         s->last_mv[i][0][1] = my << my_shift;
 979                         s->last_mv[i][1][1] = my << my_shift;
 980
 981                         s->mv[i][0][0] = mx;
 982                         s->mv[i][0][1] = my;
 983                         s->mv[i][1][0] = mx; // not used
 984                         s->mv[i][1][1] = my; // not used
 985
 986                         if (s->picture_structure == PICT_FRAME) {
 987                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 988
 989                             // m = 1 + 2 * s->top_field_first;
 990                             m = s->top_field_first ? 1 : 3;
 991
 992                             /* top -> top pred */
 993                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
 994                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
 995                             m = 4 - m;
 996                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
 997                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
 998                         } else {
 999                             mb_type |= MB_TYPE_16x16;
1000
1001                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
1002                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
1003                             if (s->picture_structure == PICT_TOP_FIELD)
1004                                 s->mv[i][2][1]--;
1005                             else
1006                                 s->mv[i][2][1]++;
1007                         }
1008                     }
1009                 }
1010                 break;
1011             default:
1012                 av_log(s->avctx, AV_LOG_ERROR,
1013                        "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
1014                 return -1;
1015             }
1016         }
1017
1018         s->mb_intra = 0;
1019         if (HAS_CBP(mb_type)) {
1020             s->bdsp.clear_blocks(s->block[0]);
1021
1022             cbp = get_vlc2(&s->gb, ff_mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
1023             if (mb_block_count > 6) {
1024                 cbp <<= mb_block_count - 6;
1025                 cbp  |= get_bits(&s->gb, mb_block_count - 6);
1026                 s->bdsp.clear_blocks(s->block[6]);
1027             }
1028             if (cbp <= 0) {
1029                 av_log(s->avctx, AV_LOG_ERROR,
1030                        "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
1031                 return -1;
1032             }
1033
1034 #if FF_API_XVMC
1035 FF_DISABLE_DEPRECATION_WARNINGS
1036             // if 1, we memcpy blocks in xvmcvideo
1037             if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
1038                 ff_xvmc_pack_pblocks(s, cbp);
1039 FF_ENABLE_DEPRECATION_WARNINGS
1040 #endif /* FF_API_XVMC */
1041
1042             if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
1043                 if (s->flags2 & CODEC_FLAG2_FAST) {
1044                     for (i = 0; i < 6; i++) {
1045                         if (cbp & 32)
1046                             mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
1047                         else
1048                             s->block_last_index[i] = -1;
1049                         cbp += cbp;
1050                     }
1051                 } else {
1052                     cbp <<= 12 - mb_block_count;
1053
1054                     for (i = 0; i < mb_block_count; i++) {
1055                         if (cbp & (1 << 11)) {
1056                             if (mpeg2_decode_block_non_intra(s, *s->pblocks[i], i) < 0)
1057                                 return -1;
1058                         } else {
1059                             s->block_last_index[i] = -1;
1060                         }
1061                         cbp += cbp;
1062                     }
1063                 }
1064             } else {
1065                 if (s->flags2 & CODEC_FLAG2_FAST) {
1066                     for (i = 0; i < 6; i++) {
1067                         if (cbp & 32)
1068                             mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
1069                         else
1070                             s->block_last_index[i] = -1;
1071                         cbp += cbp;
1072                     }
1073                 } else {
1074                     for (i = 0; i < 6; i++) {
1075                         if (cbp & 32) {
1076                             if (mpeg1_decode_block_inter(s, *s->pblocks[i], i) < 0)
1077                                 return -1;
1078                         } else {
1079                             s->block_last_index[i] = -1;
1080                         }
1081                         cbp += cbp;
1082                     }
1083                 }
1084             }
1085         } else {
1086             for (i = 0; i < 12; i++)
1087                 s->block_last_index[i] = -1;
1088         }
1089     }
1090
1091     s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] = mb_type;
1092
1093     return 0;
1094 }
1095
1096 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1097 {
1098     Mpeg1Context *s    = avctx->priv_data;
1099     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1100
1101     ff_mpv_decode_defaults(s2);
1102
1103     s->mpeg_enc_ctx.avctx  = avctx;
1104     s->mpeg_enc_ctx.flags  = avctx->flags;
1105     s->mpeg_enc_ctx.flags2 = avctx->flags2;
1106
1107     /* we need some permutation to store matrices,
1108      * until the decoder sets the real permutation. */
1109     ff_mpv_idct_init(s2);
1110     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1111     ff_mpeg12_init_vlcs();
1112
1113     s->mpeg_enc_ctx_allocated      = 0;
1114     s->mpeg_enc_ctx.picture_number = 0;
1115     s->repeat_field                = 0;
1116     s->mpeg_enc_ctx.codec_id       = avctx->codec->id;
1117     avctx->color_range             = AVCOL_RANGE_MPEG;
1118     if (avctx->codec->id == AV_CODEC_ID_MPEG1VIDEO)
1119         avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
1120     else
1121         avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
1122     return 0;
1123 }
1124
1125 static int mpeg_decode_update_thread_context(AVCodecContext *avctx,
1126                                              const AVCodecContext *avctx_from)
1127 {
1128     Mpeg1Context *ctx = avctx->priv_data, *ctx_from = avctx_from->priv_data;
1129     MpegEncContext *s = &ctx->mpeg_enc_ctx, *s1 = &ctx_from->mpeg_enc_ctx;
1130     int err;
1131
1132     if (avctx == avctx_from               ||
1133         !ctx_from->mpeg_enc_ctx_allocated ||
1134         !s1->context_initialized)
1135         return 0;
1136
1137     err = ff_mpeg_update_thread_context(avctx, avctx_from);
1138     if (err)
1139         return err;
1140
1141     if (!ctx->mpeg_enc_ctx_allocated)
1142         memcpy(s + 1, s1 + 1, sizeof(Mpeg1Context) - sizeof(MpegEncContext));
1143
1144     if (!(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay))
1145         s->picture_number++;
1146
1147     return 0;
1148 }
1149
1150 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1151                                  const uint8_t *new_perm)
1152 {
1153     uint16_t temp_matrix[64];
1154     int i;
1155
1156     memcpy(temp_matrix, matrix, 64 * sizeof(uint16_t));
1157
1158     for (i = 0; i < 64; i++)
1159         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1160 }
1161
1162 #if FF_API_XVMC
1163 static const enum AVPixelFormat pixfmt_xvmc_mpg2_420[] = {
1164     AV_PIX_FMT_XVMC_MPEG2_IDCT,
1165     AV_PIX_FMT_XVMC_MPEG2_MC,
1166     AV_PIX_FMT_NONE
1167 };
1168 #endif /* FF_API_XVMC */
1169
1170 static const enum AVPixelFormat mpeg12_hwaccel_pixfmt_list_420[] = {
1171 #if CONFIG_MPEG2_DXVA2_HWACCEL
1172     AV_PIX_FMT_DXVA2_VLD,
1173 #endif
1174 #if CONFIG_MPEG2_VAAPI_HWACCEL
1175     AV_PIX_FMT_VAAPI_VLD,
1176 #endif
1177 #if CONFIG_MPEG1_VDPAU_HWACCEL | CONFIG_MPEG2_VDPAU_HWACCEL
1178     AV_PIX_FMT_VDPAU,
1179 #endif
1180     AV_PIX_FMT_YUV420P,
1181     AV_PIX_FMT_NONE
1182 };
1183
1184 static enum AVPixelFormat mpeg_get_pixelformat(AVCodecContext *avctx)
1185 {
1186     Mpeg1Context *s1  = avctx->priv_data;
1187     MpegEncContext *s = &s1->mpeg_enc_ctx;
1188
1189 #if FF_API_XVMC
1190 FF_DISABLE_DEPRECATION_WARNINGS
1191     if (avctx->xvmc_acceleration)
1192         return ff_get_format(avctx, pixfmt_xvmc_mpg2_420);
1193 FF_ENABLE_DEPRECATION_WARNINGS
1194 #endif /* FF_API_XVMC */
1195
1196     if (s->chroma_format < 2)
1197         return ff_get_format(avctx, mpeg12_hwaccel_pixfmt_list_420);
1198     else if (s->chroma_format == 2)
1199         return AV_PIX_FMT_YUV422P;
1200     else
1201         return AV_PIX_FMT_YUV444P;
1202 }
1203
1204 /* Call this function when we know all parameters.
1205  * It may be called in different places for MPEG-1 and MPEG-2. */
1206 static int mpeg_decode_postinit(AVCodecContext *avctx)
1207 {
1208     Mpeg1Context *s1  = avctx->priv_data;
1209     MpegEncContext *s = &s1->mpeg_enc_ctx;
1210     uint8_t old_permutation[64];
1211     int ret;
1212
1213     if ((s1->mpeg_enc_ctx_allocated == 0)                   ||
1214         avctx->coded_width       != s->width                ||
1215         avctx->coded_height      != s->height               ||
1216         s1->save_width           != s->width                ||
1217         s1->save_height          != s->height               ||
1218         s1->save_aspect_info     != s->aspect_ratio_info    ||
1219         s1->save_progressive_seq != s->progressive_sequence ||
1220         0) {
1221         if (s1->mpeg_enc_ctx_allocated) {
1222             ParseContext pc = s->parse_context;
1223             s->parse_context.buffer = 0;
1224             ff_mpv_common_end(s);
1225             s->parse_context = pc;
1226         }
1227
1228         if ((s->width == 0) || (s->height == 0))
1229             return -2;
1230
1231         ret = ff_set_dimensions(avctx, s->width, s->height);
1232         if (ret < 0)
1233             return ret;
1234
1235         avctx->bit_rate          = s->bit_rate;
1236         s1->save_aspect_info     = s->aspect_ratio_info;
1237         s1->save_width           = s->width;
1238         s1->save_height          = s->height;
1239         s1->save_progressive_seq = s->progressive_sequence;
1240
1241         /* low_delay may be forced, in this case we will have B-frames
1242          * that behave like P-frames. */
1243         avctx->has_b_frames = !s->low_delay;
1244
1245         if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1246             // MPEG-1 fps
1247             avctx->time_base.den = ff_mpeg12_frame_rate_tab[s->frame_rate_index].num;
1248             avctx->time_base.num = ff_mpeg12_frame_rate_tab[s->frame_rate_index].den;
1249             // MPEG-1 aspect
1250             avctx->sample_aspect_ratio = av_d2q(1.0 / ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1251             avctx->ticks_per_frame     = 1;
1252         } else { // MPEG-2
1253             // MPEG-2 fps
1254             av_reduce(&s->avctx->time_base.den,
1255                       &s->avctx->time_base.num,
1256                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num * 2,
1257                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1258                       1 << 30);
1259             avctx->ticks_per_frame = 2;
1260             // MPEG-2 aspect
1261             if (s->aspect_ratio_info > 1) {
1262                 AVRational dar =
1263                     av_mul_q(av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1264                                       (AVRational) { s1->pan_scan.width,
1265                                                      s1->pan_scan.height }),
1266                              (AVRational) { s->width, s->height });
1267
1268                 /* We ignore the spec here and guess a bit as reality does not
1269                  * match the spec, see for example res_change_ffmpeg_aspect.ts
1270                  * and sequence-display-aspect.mpg.
1271                  * issue1613, 621, 562 */
1272                 if ((s1->pan_scan.width == 0) || (s1->pan_scan.height == 0) ||
1273                     (av_cmp_q(dar, (AVRational) { 4, 3 }) &&
1274                      av_cmp_q(dar, (AVRational) { 16, 9 }))) {
1275                     s->avctx->sample_aspect_ratio =
1276                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1277                                  (AVRational) { s->width, s->height });
1278                 } else {
1279                     s->avctx->sample_aspect_ratio =
1280                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1281                                  (AVRational) { s1->pan_scan.width, s1->pan_scan.height });
1282 // issue1613 4/3 16/9 -> 16/9
1283 // res_change_ffmpeg_aspect.ts 4/3 225/44 ->4/3
1284 // widescreen-issue562.mpg 4/3 16/9 -> 16/9
1285 //                    s->avctx->sample_aspect_ratio = av_mul_q(s->avctx->sample_aspect_ratio, (AVRational) {s->width, s->height});
1286                     av_dlog(avctx, "A %d/%d\n",
1287                             ff_mpeg2_aspect[s->aspect_ratio_info].num,
1288                             ff_mpeg2_aspect[s->aspect_ratio_info].den);
1289                     av_dlog(avctx, "B %d/%d\n", s->avctx->sample_aspect_ratio.num,
1290                             s->avctx->sample_aspect_ratio.den);
1291                 }
1292             } else {
1293                 s->avctx->sample_aspect_ratio =
1294                     ff_mpeg2_aspect[s->aspect_ratio_info];
1295             }
1296         } // MPEG-2
1297
1298         ff_set_sar(s->avctx, s->avctx->sample_aspect_ratio);
1299
1300         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1301         // until then pix_fmt may be changed right after codec init
1302 #if FF_API_XVMC
1303         if ((avctx->pix_fmt == AV_PIX_FMT_XVMC_MPEG2_IDCT ||
1304              avctx->hwaccel) && avctx->idct_algo == FF_IDCT_AUTO)
1305 #else
1306         if (avctx->hwaccel && avctx->idct_algo == FF_IDCT_AUTO)
1307 #endif /* FF_API_XVMC */
1308             avctx->idct_algo = FF_IDCT_SIMPLE;
1309
1310         /* Quantization matrices may need reordering
1311          * if DCT permutation is changed. */
1312         memcpy(old_permutation, s->idsp.idct_permutation, 64 * sizeof(uint8_t));
1313
1314         ff_mpv_idct_init(s);
1315         if (ff_mpv_common_init(s) < 0)
1316             return -2;
1317
1318         quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->idsp.idct_permutation);
1319         quant_matrix_rebuild(s->inter_matrix,        old_permutation, s->idsp.idct_permutation);
1320         quant_matrix_rebuild(s->chroma_intra_matrix, old_permutation, s->idsp.idct_permutation);
1321         quant_matrix_rebuild(s->chroma_inter_matrix, old_permutation, s->idsp.idct_permutation);
1322
1323         s1->mpeg_enc_ctx_allocated = 1;
1324     }
1325     return 0;
1326 }
1327
1328 static int mpeg1_decode_picture(AVCodecContext *avctx, const uint8_t *buf,
1329                                 int buf_size)
1330 {
1331     Mpeg1Context *s1  = avctx->priv_data;
1332     MpegEncContext *s = &s1->mpeg_enc_ctx;
1333     int ref, f_code, vbv_delay;
1334
1335     init_get_bits(&s->gb, buf, buf_size * 8);
1336
1337     ref = get_bits(&s->gb, 10); /* temporal ref */
1338     s->pict_type = get_bits(&s->gb, 3);
1339     if (s->pict_type == 0 || s->pict_type > 3)
1340         return -1;
1341
1342     vbv_delay = get_bits(&s->gb, 16);
1343     if (s->pict_type == AV_PICTURE_TYPE_P ||
1344         s->pict_type == AV_PICTURE_TYPE_B) {
1345         s->full_pel[0] = get_bits1(&s->gb);
1346         f_code = get_bits(&s->gb, 3);
1347         if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
1348             return -1;
1349         s->mpeg_f_code[0][0] = f_code;
1350         s->mpeg_f_code[0][1] = f_code;
1351     }
1352     if (s->pict_type == AV_PICTURE_TYPE_B) {
1353         s->full_pel[1] = get_bits1(&s->gb);
1354         f_code = get_bits(&s->gb, 3);
1355         if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
1356             return -1;
1357         s->mpeg_f_code[1][0] = f_code;
1358         s->mpeg_f_code[1][1] = f_code;
1359     }
1360     s->current_picture.f->pict_type = s->pict_type;
1361     s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1362
1363     if (avctx->debug & FF_DEBUG_PICT_INFO)
1364         av_log(avctx, AV_LOG_DEBUG,
1365                "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1366
1367     s->y_dc_scale = 8;
1368     s->c_dc_scale = 8;
1369     return 0;
1370 }
1371
1372 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1373 {
1374     MpegEncContext *s = &s1->mpeg_enc_ctx;
1375     int horiz_size_ext, vert_size_ext;
1376     int bit_rate_ext;
1377
1378     skip_bits(&s->gb, 1); /* profile and level esc*/
1379     s->avctx->profile       = get_bits(&s->gb, 3);
1380     s->avctx->level         = get_bits(&s->gb, 4);
1381     s->progressive_sequence = get_bits1(&s->gb);   /* progressive_sequence */
1382     s->chroma_format        = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1383     horiz_size_ext          = get_bits(&s->gb, 2);
1384     vert_size_ext           = get_bits(&s->gb, 2);
1385     s->width  |= (horiz_size_ext << 12);
1386     s->height |= (vert_size_ext  << 12);
1387     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1388     s->bit_rate += (bit_rate_ext << 18) * 400;
1389     skip_bits1(&s->gb); /* marker */
1390     s->avctx->rc_buffer_size += get_bits(&s->gb, 8) * 1024 * 16 << 10;
1391
1392     s->low_delay = get_bits1(&s->gb);
1393     if (s->flags & CODEC_FLAG_LOW_DELAY)
1394         s->low_delay = 1;
1395
1396     s1->frame_rate_ext.num = get_bits(&s->gb, 2) + 1;
1397     s1->frame_rate_ext.den = get_bits(&s->gb, 5) + 1;
1398
1399     av_dlog(s->avctx, "sequence extension\n");
1400     s->codec_id = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
1401
1402     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1403         av_log(s->avctx, AV_LOG_DEBUG,
1404                "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
1405                s->avctx->profile, s->avctx->level,
1406                s->avctx->rc_buffer_size, s->bit_rate);
1407 }
1408
1409 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1410 {
1411     MpegEncContext *s = &s1->mpeg_enc_ctx;
1412     int color_description, w, h;
1413
1414     skip_bits(&s->gb, 3); /* video format */
1415     color_description = get_bits1(&s->gb);
1416     if (color_description) {
1417         s->avctx->color_primaries = get_bits(&s->gb, 8);
1418         s->avctx->color_trc       = get_bits(&s->gb, 8);
1419         s->avctx->colorspace      = get_bits(&s->gb, 8);
1420     }
1421     w = get_bits(&s->gb, 14);
1422     skip_bits(&s->gb, 1); // marker
1423     h = get_bits(&s->gb, 14);
1424     // remaining 3 bits are zero padding
1425
1426     s1->pan_scan.width  = 16 * w;
1427     s1->pan_scan.height = 16 * h;
1428
1429     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1430         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1431 }
1432
1433 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1434 {
1435     MpegEncContext *s = &s1->mpeg_enc_ctx;
1436     int i, nofco;
1437
1438     nofco = 1;
1439     if (s->progressive_sequence) {
1440         if (s->repeat_first_field) {
1441             nofco++;
1442             if (s->top_field_first)
1443                 nofco++;
1444         }
1445     } else {
1446         if (s->picture_structure == PICT_FRAME) {
1447             nofco++;
1448             if (s->repeat_first_field)
1449                 nofco++;
1450         }
1451     }
1452     for (i = 0; i < nofco; i++) {
1453         s1->pan_scan.position[i][0] = get_sbits(&s->gb, 16);
1454         skip_bits(&s->gb, 1); // marker
1455         s1->pan_scan.position[i][1] = get_sbits(&s->gb, 16);
1456         skip_bits(&s->gb, 1); // marker
1457     }
1458
1459     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1460         av_log(s->avctx, AV_LOG_DEBUG,
1461                "pde (%"PRId16",%"PRId16") (%"PRId16",%"PRId16") (%"PRId16",%"PRId16")\n",
1462                s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1463                s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1464                s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]);
1465 }
1466
1467 static int load_matrix(MpegEncContext *s, uint16_t matrix0[64],
1468                        uint16_t matrix1[64], int intra)
1469 {
1470     int i;
1471
1472     for (i = 0; i < 64; i++) {
1473         int j = s->idsp.idct_permutation[ff_zigzag_direct[i]];
1474         int v = get_bits(&s->gb, 8);
1475         if (v == 0) {
1476             av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
1477             return -1;
1478         }
1479         if (intra && i == 0 && v != 8) {
1480             av_log(s->avctx, AV_LOG_ERROR, "intra matrix invalid, ignoring\n");
1481             v = 8; // needed by pink.mpg / issue1046
1482         }
1483         matrix0[j] = v;
1484         if (matrix1)
1485             matrix1[j] = v;
1486     }
1487     return 0;
1488 }
1489
1490 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1491 {
1492     av_dlog(s->avctx, "matrix extension\n");
1493
1494     if (get_bits1(&s->gb))
1495         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1496     if (get_bits1(&s->gb))
1497         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1498     if (get_bits1(&s->gb))
1499         load_matrix(s, s->chroma_intra_matrix, NULL, 1);
1500     if (get_bits1(&s->gb))
1501         load_matrix(s, s->chroma_inter_matrix, NULL, 0);
1502 }
1503
1504 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1505 {
1506     MpegEncContext *s = &s1->mpeg_enc_ctx;
1507
1508     s->full_pel[0]       = s->full_pel[1] = 0;
1509     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1510     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1511     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1512     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1513     if (!s->pict_type && s1->mpeg_enc_ctx_allocated) {
1514         av_log(s->avctx, AV_LOG_ERROR,
1515                "Missing picture start code, guessing missing values\n");
1516         if (s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1] == 15) {
1517             if (s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1518                 s->pict_type = AV_PICTURE_TYPE_I;
1519             else
1520                 s->pict_type = AV_PICTURE_TYPE_P;
1521         } else
1522             s->pict_type = AV_PICTURE_TYPE_B;
1523         s->current_picture.f->pict_type = s->pict_type;
1524         s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1525     }
1526     s->intra_dc_precision         = get_bits(&s->gb, 2);
1527     s->picture_structure          = get_bits(&s->gb, 2);
1528     s->top_field_first            = get_bits1(&s->gb);
1529     s->frame_pred_frame_dct       = get_bits1(&s->gb);
1530     s->concealment_motion_vectors = get_bits1(&s->gb);
1531     s->q_scale_type               = get_bits1(&s->gb);
1532     s->intra_vlc_format           = get_bits1(&s->gb);
1533     s->alternate_scan             = get_bits1(&s->gb);
1534     s->repeat_first_field         = get_bits1(&s->gb);
1535     s->chroma_420_type            = get_bits1(&s->gb);
1536     s->progressive_frame          = get_bits1(&s->gb);
1537
1538     if (s->progressive_sequence && !s->progressive_frame) {
1539         s->progressive_frame = 1;
1540         av_log(s->avctx, AV_LOG_ERROR,
1541                "interlaced frame in progressive sequence, ignoring\n");
1542     }
1543
1544     if (s->picture_structure == 0 ||
1545         (s->progressive_frame && s->picture_structure != PICT_FRAME)) {
1546         av_log(s->avctx, AV_LOG_ERROR,
1547                "picture_structure %d invalid, ignoring\n",
1548                s->picture_structure);
1549         s->picture_structure = PICT_FRAME;
1550     }
1551
1552     if (s->progressive_sequence && !s->frame_pred_frame_dct)
1553         av_log(s->avctx, AV_LOG_WARNING, "invalid frame_pred_frame_dct\n");
1554
1555     if (s->picture_structure == PICT_FRAME) {
1556         s->first_field = 0;
1557         s->v_edge_pos  = 16 * s->mb_height;
1558     } else {
1559         s->first_field ^= 1;
1560         s->v_edge_pos   = 8 * s->mb_height;
1561         memset(s->mbskip_table, 0, s->mb_stride * s->mb_height);
1562     }
1563
1564     if (s->alternate_scan) {
1565         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
1566         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);
1567     } else {
1568         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
1569         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
1570     }
1571
1572     /* composite display not parsed */
1573     av_dlog(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1574     av_dlog(s->avctx, "picture_structure=%d\n", s->picture_structure);
1575     av_dlog(s->avctx, "top field first=%d\n", s->top_field_first);
1576     av_dlog(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1577     av_dlog(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1578     av_dlog(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1579     av_dlog(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1580     av_dlog(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1581     av_dlog(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1582 }
1583
1584 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
1585 {
1586     AVCodecContext *avctx = s->avctx;
1587     Mpeg1Context *s1      = (Mpeg1Context *) s;
1588
1589     /* start frame decoding */
1590     if (s->first_field || s->picture_structure == PICT_FRAME) {
1591         AVFrameSideData *pan_scan;
1592
1593         if (ff_mpv_frame_start(s, avctx) < 0)
1594             return -1;
1595
1596         ff_mpeg_er_frame_start(s);
1597
1598         /* first check if we must repeat the frame */
1599         s->current_picture_ptr->f->repeat_pict = 0;
1600         if (s->repeat_first_field) {
1601             if (s->progressive_sequence) {
1602                 if (s->top_field_first)
1603                     s->current_picture_ptr->f->repeat_pict = 4;
1604                 else
1605                     s->current_picture_ptr->f->repeat_pict = 2;
1606             } else if (s->progressive_frame) {
1607                 s->current_picture_ptr->f->repeat_pict = 1;
1608             }
1609         }
1610
1611         pan_scan = av_frame_new_side_data(s->current_picture_ptr->f,
1612                                           AV_FRAME_DATA_PANSCAN,
1613                                           sizeof(s1->pan_scan));
1614         if (!pan_scan)
1615             return AVERROR(ENOMEM);
1616         memcpy(pan_scan->data, &s1->pan_scan, sizeof(s1->pan_scan));
1617
1618         if (s1->a53_caption) {
1619             AVFrameSideData *sd = av_frame_new_side_data(
1620                 s->current_picture_ptr->f, AV_FRAME_DATA_A53_CC,
1621                 s1->a53_caption_size);
1622             if (sd)
1623                 memcpy(sd->data, s1->a53_caption, s1->a53_caption_size);
1624             av_freep(&s1->a53_caption);
1625         }
1626
1627         if (s1->has_stereo3d) {
1628             AVStereo3D *stereo = av_stereo3d_create_side_data(s->current_picture_ptr->f);
1629             if (!stereo)
1630                 return AVERROR(ENOMEM);
1631
1632             *stereo = s1->stereo3d;
1633             s1->has_stereo3d = 0;
1634         }
1635
1636         if (s1->has_afd) {
1637             AVFrameSideData *sd =
1638                 av_frame_new_side_data(s->current_picture_ptr->f,
1639                                        AV_FRAME_DATA_AFD, 1);
1640             if (!sd)
1641                 return AVERROR(ENOMEM);
1642
1643             *sd->data   = s1->afd;
1644             s1->has_afd = 0;
1645         }
1646
1647         if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
1648             ff_thread_finish_setup(avctx);
1649     } else { // second field
1650         int i;
1651
1652         if (!s->current_picture_ptr) {
1653             av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1654             return -1;
1655         }
1656
1657         if (s->avctx->hwaccel &&
1658             (s->avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
1659             if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1660                 av_log(avctx, AV_LOG_ERROR,
1661                        "hardware accelerator failed to decode first field\n");
1662         }
1663
1664         for (i = 0; i < 4; i++) {
1665             s->current_picture.f->data[i] = s->current_picture_ptr->f->data[i];
1666             if (s->picture_structure == PICT_BOTTOM_FIELD)
1667                 s->current_picture.f->data[i] +=
1668                     s->current_picture_ptr->f->linesize[i];
1669         }
1670     }
1671
1672     if (avctx->hwaccel) {
1673         if (avctx->hwaccel->start_frame(avctx, buf, buf_size) < 0)
1674             return -1;
1675     }
1676
1677 #if FF_API_XVMC
1678 FF_DISABLE_DEPRECATION_WARNINGS
1679 // ff_mpv_frame_start will call this function too,
1680 // but we need to call it on every field
1681     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
1682         if (ff_xvmc_field_start(s, avctx) < 0)
1683             return -1;
1684 FF_ENABLE_DEPRECATION_WARNINGS
1685 #endif /* FF_API_XVMC */
1686
1687     return 0;
1688 }
1689
1690 #define DECODE_SLICE_ERROR -1
1691 #define DECODE_SLICE_OK     0
1692
1693 /**
1694  * Decode a slice.
1695  * MpegEncContext.mb_y must be set to the MB row from the startcode.
1696  * @return DECODE_SLICE_ERROR if the slice is damaged,
1697  *         DECODE_SLICE_OK if this slice is OK
1698  */
1699 static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
1700                              const uint8_t **buf, int buf_size)
1701 {
1702     AVCodecContext *avctx = s->avctx;
1703     const int field_pic   = s->picture_structure != PICT_FRAME;
1704
1705     s->resync_mb_x =
1706     s->resync_mb_y = -1;
1707
1708     assert(mb_y < s->mb_height);
1709
1710     init_get_bits(&s->gb, *buf, buf_size * 8);
1711
1712     ff_mpeg1_clean_buffers(s);
1713     s->interlaced_dct = 0;
1714
1715     s->qscale = get_qscale(s);
1716
1717     if (s->qscale == 0) {
1718         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1719         return -1;
1720     }
1721
1722     /* extra slice info */
1723     while (get_bits1(&s->gb) != 0)
1724         skip_bits(&s->gb, 8);
1725
1726     s->mb_x = 0;
1727
1728     if (mb_y == 0 && s->codec_tag == AV_RL32("SLIF")) {
1729         skip_bits1(&s->gb);
1730     } else {
1731         while (get_bits_left(&s->gb) > 0) {
1732             int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1733                                 MBINCR_VLC_BITS, 2);
1734             if (code < 0) {
1735                 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1736                 return -1;
1737             }
1738             if (code >= 33) {
1739                 if (code == 33)
1740                     s->mb_x += 33;
1741                 /* otherwise, stuffing, nothing to do */
1742             } else {
1743                 s->mb_x += code;
1744                 break;
1745             }
1746         }
1747     }
1748
1749     if (s->mb_x >= (unsigned) s->mb_width) {
1750         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1751         return -1;
1752     }
1753
1754     if (avctx->hwaccel) {
1755         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
1756         int start_code = -1;
1757         buf_end = avpriv_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
1758         if (buf_end < *buf + buf_size)
1759             buf_end -= 4;
1760         s->mb_y = mb_y;
1761         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
1762             return DECODE_SLICE_ERROR;
1763         *buf = buf_end;
1764         return DECODE_SLICE_OK;
1765     }
1766
1767     s->resync_mb_x = s->mb_x;
1768     s->resync_mb_y = s->mb_y = mb_y;
1769     s->mb_skip_run = 0;
1770     ff_init_block_index(s);
1771
1772     if (s->mb_y == 0 && s->mb_x == 0 && (s->first_field || s->picture_structure == PICT_FRAME)) {
1773         if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
1774             av_log(s->avctx, AV_LOG_DEBUG,
1775                    "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",
1776                    s->qscale,
1777                    s->mpeg_f_code[0][0], s->mpeg_f_code[0][1],
1778                    s->mpeg_f_code[1][0], s->mpeg_f_code[1][1],
1779                    s->pict_type  == AV_PICTURE_TYPE_I ? "I" :
1780                    (s->pict_type == AV_PICTURE_TYPE_P ? "P" :
1781                    (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
1782                    s->progressive_sequence ? "ps"  : "",
1783                    s->progressive_frame    ? "pf"  : "",
1784                    s->alternate_scan       ? "alt" : "",
1785                    s->top_field_first      ? "top" : "",
1786                    s->intra_dc_precision, s->picture_structure,
1787                    s->frame_pred_frame_dct, s->concealment_motion_vectors,
1788                    s->q_scale_type, s->intra_vlc_format,
1789                    s->repeat_first_field, s->chroma_420_type ? "420" : "");
1790         }
1791     }
1792
1793     for (;;) {
1794 #if FF_API_XVMC
1795 FF_DISABLE_DEPRECATION_WARNINGS
1796         // If 1, we memcpy blocks in xvmcvideo.
1797         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
1798             ff_xvmc_init_block(s); // set s->block
1799 FF_ENABLE_DEPRECATION_WARNINGS
1800 #endif /* FF_API_XVMC */
1801
1802         if (mpeg_decode_mb(s, s->block) < 0)
1803             return -1;
1804
1805         // Note motion_val is normally NULL unless we want to extract the MVs.
1806         if (s->current_picture.motion_val[0] && !s->encoding) {
1807             const int wrap = s->b8_stride;
1808             int xy         = s->mb_x * 2 + s->mb_y * 2 * wrap;
1809             int b8_xy      = 4 * (s->mb_x + s->mb_y * s->mb_stride);
1810             int motion_x, motion_y, dir, i;
1811
1812             for (i = 0; i < 2; i++) {
1813                 for (dir = 0; dir < 2; dir++) {
1814                     if (s->mb_intra ||
1815                         (dir == 1 && s->pict_type != AV_PICTURE_TYPE_B)) {
1816                         motion_x = motion_y = 0;
1817                     } else if (s->mv_type == MV_TYPE_16X16 ||
1818                                (s->mv_type == MV_TYPE_FIELD && field_pic)) {
1819                         motion_x = s->mv[dir][0][0];
1820                         motion_y = s->mv[dir][0][1];
1821                     } else { /* if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8)) */
1822                         motion_x = s->mv[dir][i][0];
1823                         motion_y = s->mv[dir][i][1];
1824                     }
1825
1826                     s->current_picture.motion_val[dir][xy][0]     = motion_x;
1827                     s->current_picture.motion_val[dir][xy][1]     = motion_y;
1828                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1829                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1830                     s->current_picture.ref_index [dir][b8_xy]     =
1831                     s->current_picture.ref_index [dir][b8_xy + 1] = s->field_select[dir][i];
1832                     assert(s->field_select[dir][i] == 0 ||
1833                            s->field_select[dir][i] == 1);
1834                 }
1835                 xy    += wrap;
1836                 b8_xy += 2;
1837             }
1838         }
1839
1840         s->dest[0] += 16;
1841         s->dest[1] += 16 >> s->chroma_x_shift;
1842         s->dest[2] += 16 >> s->chroma_x_shift;
1843
1844         ff_mpv_decode_mb(s, s->block);
1845
1846         if (++s->mb_x >= s->mb_width) {
1847             const int mb_size = 16;
1848
1849             ff_mpeg_draw_horiz_band(s, mb_size * (s->mb_y >> field_pic), mb_size);
1850             ff_mpv_report_decode_progress(s);
1851
1852             s->mb_x  = 0;
1853             s->mb_y += 1 << field_pic;
1854
1855             if (s->mb_y >= s->mb_height) {
1856                 int left   = get_bits_left(&s->gb);
1857                 int is_d10 = s->chroma_format == 2 &&
1858                              s->pict_type == AV_PICTURE_TYPE_I &&
1859                              avctx->profile == 0 && avctx->level == 5 &&
1860                              s->intra_dc_precision == 2 &&
1861                              s->q_scale_type == 1 && s->alternate_scan == 0 &&
1862                              s->progressive_frame == 0
1863                              /* vbv_delay == 0xBBB || 0xE10 */;
1864
1865                 if (left < 0 ||
1866                     (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10) ||
1867                     ((avctx->err_recognition & AV_EF_BUFFER) && left > 8)) {
1868                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n",
1869                            left, show_bits(&s->gb, FFMIN(left, 23)));
1870                     return -1;
1871                 } else
1872                     goto eos;
1873             }
1874
1875             ff_init_block_index(s);
1876         }
1877
1878         /* skip mb handling */
1879         if (s->mb_skip_run == -1) {
1880             /* read increment again */
1881             s->mb_skip_run = 0;
1882             for (;;) {
1883                 int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1884                                     MBINCR_VLC_BITS, 2);
1885                 if (code < 0) {
1886                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1887                     return -1;
1888                 }
1889                 if (code >= 33) {
1890                     if (code == 33) {
1891                         s->mb_skip_run += 33;
1892                     } else if (code == 35) {
1893                         if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
1894                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1895                             return -1;
1896                         }
1897                         goto eos; /* end of slice */
1898                     }
1899                     /* otherwise, stuffing, nothing to do */
1900                 } else {
1901                     s->mb_skip_run += code;
1902                     break;
1903                 }
1904             }
1905             if (s->mb_skip_run) {
1906                 int i;
1907                 if (s->pict_type == AV_PICTURE_TYPE_I) {
1908                     av_log(s->avctx, AV_LOG_ERROR,
1909                            "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1910                     return -1;
1911                 }
1912
1913                 /* skip mb */
1914                 s->mb_intra = 0;
1915                 for (i = 0; i < 12; i++)
1916                     s->block_last_index[i] = -1;
1917                 if (s->picture_structure == PICT_FRAME)
1918                     s->mv_type = MV_TYPE_16X16;
1919                 else
1920                     s->mv_type = MV_TYPE_FIELD;
1921                 if (s->pict_type == AV_PICTURE_TYPE_P) {
1922                     /* if P type, zero motion vector is implied */
1923                     s->mv_dir             = MV_DIR_FORWARD;
1924                     s->mv[0][0][0]        = s->mv[0][0][1]      = 0;
1925                     s->last_mv[0][0][0]   = s->last_mv[0][0][1] = 0;
1926                     s->last_mv[0][1][0]   = s->last_mv[0][1][1] = 0;
1927                     s->field_select[0][0] = (s->picture_structure - 1) & 1;
1928                 } else {
1929                     /* if B type, reuse previous vectors and directions */
1930                     s->mv[0][0][0] = s->last_mv[0][0][0];
1931                     s->mv[0][0][1] = s->last_mv[0][0][1];
1932                     s->mv[1][0][0] = s->last_mv[1][0][0];
1933                     s->mv[1][0][1] = s->last_mv[1][0][1];
1934                 }
1935             }
1936         }
1937     }
1938 eos: // end of slice
1939     *buf += (get_bits_count(&s->gb) - 1) / 8;
1940     av_dlog(s, "y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1941     return 0;
1942 }
1943
1944 static int slice_decode_thread(AVCodecContext *c, void *arg)
1945 {
1946     MpegEncContext *s   = *(void **) arg;
1947     const uint8_t *buf  = s->gb.buffer;
1948     int mb_y            = s->start_mb_y;
1949     const int field_pic = s->picture_structure != PICT_FRAME;
1950
1951     s->er.error_count = (3 * (s->end_mb_y - s->start_mb_y) * s->mb_width) >> field_pic;
1952
1953     for (;;) {
1954         uint32_t start_code;
1955         int ret;
1956
1957         ret = mpeg_decode_slice(s, mb_y, &buf, s->gb.buffer_end - buf);
1958         emms_c();
1959         av_dlog(c, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
1960                 ret, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y,
1961                 s->start_mb_y, s->end_mb_y, s->er.error_count);
1962         if (ret < 0) {
1963             if (c->err_recognition & AV_EF_EXPLODE)
1964                 return ret;
1965             if (s->resync_mb_x >= 0 && s->resync_mb_y >= 0)
1966                 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
1967                                 s->mb_x, s->mb_y,
1968                                 ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
1969         } else {
1970             ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
1971                             s->mb_x - 1, s->mb_y,
1972                             ER_AC_END | ER_DC_END | ER_MV_END);
1973         }
1974
1975         if (s->mb_y == s->end_mb_y)
1976             return 0;
1977
1978         start_code = -1;
1979         buf        = avpriv_find_start_code(buf, s->gb.buffer_end, &start_code);
1980         mb_y       = (start_code - SLICE_MIN_START_CODE) << field_pic;
1981         if (s->picture_structure == PICT_BOTTOM_FIELD)
1982             mb_y++;
1983         if (mb_y < 0 || mb_y >= s->end_mb_y)
1984             return -1;
1985     }
1986 }
1987
1988 /**
1989  * Handle slice ends.
1990  * @return 1 if it seems to be the last slice
1991  */
1992 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
1993 {
1994     Mpeg1Context *s1  = avctx->priv_data;
1995     MpegEncContext *s = &s1->mpeg_enc_ctx;
1996
1997     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
1998         return 0;
1999
2000     if (s->avctx->hwaccel) {
2001         if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
2002             av_log(avctx, AV_LOG_ERROR,
2003                    "hardware accelerator failed to decode picture\n");
2004     }
2005
2006 #if FF_API_XVMC
2007 FF_DISABLE_DEPRECATION_WARNINGS
2008     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
2009         ff_xvmc_field_end(s);
2010 FF_ENABLE_DEPRECATION_WARNINGS
2011 #endif /* FF_API_XVMC */
2012
2013     /* end of slice reached */
2014     if (/* s->mb_y << field_pic == s->mb_height && */ !s->first_field) {
2015         /* end of image */
2016
2017         ff_er_frame_end(&s->er);
2018
2019         ff_mpv_frame_end(s);
2020
2021         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
2022             int ret = av_frame_ref(pict, s->current_picture_ptr->f);
2023             if (ret < 0)
2024                 return ret;
2025             ff_print_debug_info(s, s->current_picture_ptr);
2026         } else {
2027             if (avctx->active_thread_type & FF_THREAD_FRAME)
2028                 s->picture_number++;
2029             /* latency of 1 frame for I- and P-frames */
2030             /* XXX: use another variable than picture_number */
2031             if (s->last_picture_ptr != NULL) {
2032                 int ret = av_frame_ref(pict, s->last_picture_ptr->f);
2033                 if (ret < 0)
2034                     return ret;
2035                 ff_print_debug_info(s, s->last_picture_ptr);
2036             }
2037         }
2038
2039         return 1;
2040     } else {
2041         return 0;
2042     }
2043 }
2044
2045 static int mpeg1_decode_sequence(AVCodecContext *avctx,
2046                                  const uint8_t *buf, int buf_size)
2047 {
2048     Mpeg1Context *s1  = avctx->priv_data;
2049     MpegEncContext *s = &s1->mpeg_enc_ctx;
2050     int width, height;
2051     int i, v, j;
2052
2053     init_get_bits(&s->gb, buf, buf_size * 8);
2054
2055     width  = get_bits(&s->gb, 12);
2056     height = get_bits(&s->gb, 12);
2057     if (width == 0 || height == 0) {
2058         av_log(avctx, AV_LOG_WARNING,
2059                "Invalid horizontal or vertical size value.\n");
2060         if (avctx->err_recognition & AV_EF_BITSTREAM)
2061             return AVERROR_INVALIDDATA;
2062     }
2063     s->aspect_ratio_info = get_bits(&s->gb, 4);
2064     if (s->aspect_ratio_info == 0) {
2065         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
2066         if (avctx->err_recognition & AV_EF_BITSTREAM)
2067             return -1;
2068     }
2069     s->frame_rate_index = get_bits(&s->gb, 4);
2070     if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
2071         return -1;
2072     s->bit_rate = get_bits(&s->gb, 18) * 400;
2073     if (get_bits1(&s->gb) == 0) /* marker */
2074         return -1;
2075     s->width  = width;
2076     s->height = height;
2077
2078     s->avctx->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
2079     skip_bits(&s->gb, 1);
2080
2081     /* get matrix */
2082     if (get_bits1(&s->gb)) {
2083         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
2084     } else {
2085         for (i = 0; i < 64; i++) {
2086             j = s->idsp.idct_permutation[i];
2087             v = ff_mpeg1_default_intra_matrix[i];
2088             s->intra_matrix[j]        = v;
2089             s->chroma_intra_matrix[j] = v;
2090         }
2091     }
2092     if (get_bits1(&s->gb)) {
2093         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
2094     } else {
2095         for (i = 0; i < 64; i++) {
2096             int j = s->idsp.idct_permutation[i];
2097             v = ff_mpeg1_default_non_intra_matrix[i];
2098             s->inter_matrix[j]        = v;
2099             s->chroma_inter_matrix[j] = v;
2100         }
2101     }
2102
2103     if (show_bits(&s->gb, 23) != 0) {
2104         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2105         return -1;
2106     }
2107
2108     /* We set MPEG-2 parameters so that it emulates MPEG-1. */
2109     s->progressive_sequence = 1;
2110     s->progressive_frame    = 1;
2111     s->picture_structure    = PICT_FRAME;
2112     s->frame_pred_frame_dct = 1;
2113     s->chroma_format        = 1;
2114     s->codec_id             =
2115     s->avctx->codec_id      = AV_CODEC_ID_MPEG1VIDEO;
2116     s->out_format           = FMT_MPEG1;
2117     if (s->flags & CODEC_FLAG_LOW_DELAY)
2118         s->low_delay = 1;
2119
2120     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2121         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
2122                s->avctx->rc_buffer_size, s->bit_rate);
2123
2124     return 0;
2125 }
2126
2127 static int vcr2_init_sequence(AVCodecContext *avctx)
2128 {
2129     Mpeg1Context *s1  = avctx->priv_data;
2130     MpegEncContext *s = &s1->mpeg_enc_ctx;
2131     int i, v;
2132
2133     /* start new MPEG-1 context decoding */
2134     s->out_format = FMT_MPEG1;
2135     if (s1->mpeg_enc_ctx_allocated) {
2136         ff_mpv_common_end(s);
2137     }
2138     s->width            = avctx->coded_width;
2139     s->height           = avctx->coded_height;
2140     avctx->has_b_frames = 0; // true?
2141     s->low_delay        = 1;
2142
2143     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
2144
2145 #if FF_API_XVMC
2146     if ((avctx->pix_fmt == AV_PIX_FMT_XVMC_MPEG2_IDCT || avctx->hwaccel) &&
2147         avctx->idct_algo == FF_IDCT_AUTO)
2148 #else
2149     if (avctx->hwaccel && avctx->idct_algo == FF_IDCT_AUTO)
2150 #endif /* FF_API_XVMC */
2151         avctx->idct_algo = FF_IDCT_SIMPLE;
2152
2153     ff_mpv_idct_init(s);
2154     if (ff_mpv_common_init(s) < 0)
2155         return -1;
2156     s1->mpeg_enc_ctx_allocated = 1;
2157
2158     for (i = 0; i < 64; i++) {
2159         int j = s->idsp.idct_permutation[i];
2160         v = ff_mpeg1_default_intra_matrix[i];
2161         s->intra_matrix[j]        = v;
2162         s->chroma_intra_matrix[j] = v;
2163
2164         v = ff_mpeg1_default_non_intra_matrix[i];
2165         s->inter_matrix[j]        = v;
2166         s->chroma_inter_matrix[j] = v;
2167     }
2168
2169     s->progressive_sequence  = 1;
2170     s->progressive_frame     = 1;
2171     s->picture_structure     = PICT_FRAME;
2172     s->frame_pred_frame_dct  = 1;
2173     s->chroma_format         = 1;
2174     s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
2175     s1->save_width           = s->width;
2176     s1->save_height          = s->height;
2177     s1->save_progressive_seq = s->progressive_sequence;
2178     return 0;
2179 }
2180
2181 static int mpeg_decode_a53_cc(AVCodecContext *avctx,
2182                               const uint8_t *p, int buf_size)
2183 {
2184     Mpeg1Context *s1 = avctx->priv_data;
2185
2186     if (buf_size >= 6 &&
2187         p[0] == 'G' && p[1] == 'A' && p[2] == '9' && p[3] == '4' &&
2188         p[4] == 3 && (p[5] & 0x40)) {
2189         /* extract A53 Part 4 CC data */
2190         int cc_count = p[5] & 0x1f;
2191         if (cc_count > 0 && buf_size >= 7 + cc_count * 3) {
2192             av_freep(&s1->a53_caption);
2193             s1->a53_caption_size = cc_count * 3;
2194             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2195             if (s1->a53_caption)
2196                 memcpy(s1->a53_caption, p + 7, s1->a53_caption_size);
2197         }
2198         return 1;
2199     } else if (buf_size >= 11 &&
2200                p[0] == 'C' && p[1] == 'C' && p[2] == 0x01 && p[3] == 0xf8) {
2201         /* extract DVD CC data */
2202         int cc_count = 0;
2203         int i;
2204         // There is a caption count field in the data, but it is often
2205         // incorect.  So count the number of captions present.
2206         for (i = 5; i + 6 <= buf_size && ((p[i] & 0xfe) == 0xfe); i += 6)
2207             cc_count++;
2208         // Transform the DVD format into A53 Part 4 format
2209         if (cc_count > 0) {
2210             av_freep(&s1->a53_caption);
2211             s1->a53_caption_size = cc_count * 6;
2212             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2213             if (s1->a53_caption) {
2214                 uint8_t field1 = !!(p[4] & 0x80);
2215                 uint8_t *cap = s1->a53_caption;
2216                 p += 5;
2217                 for (i = 0; i < cc_count; i++) {
2218                     cap[0] = (p[0] == 0xff && field1) ? 0xfc : 0xfd;
2219                     cap[1] = p[1];
2220                     cap[2] = p[2];
2221                     cap[3] = (p[3] == 0xff && !field1) ? 0xfc : 0xfd;
2222                     cap[4] = p[4];
2223                     cap[5] = p[5];
2224                     cap += 6;
2225                     p += 6;
2226                 }
2227             }
2228         }
2229         return 1;
2230     }
2231     return 0;
2232 }
2233
2234 static void mpeg_decode_user_data(AVCodecContext *avctx,
2235                                   const uint8_t *p, int buf_size)
2236 {
2237     const uint8_t *buf_end = p + buf_size;
2238     Mpeg1Context *s1 = avctx->priv_data;
2239
2240     /* we parse the DTG active format information */
2241     if (buf_end - p >= 5 &&
2242         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2243         int flags = p[4];
2244         p += 5;
2245         if (flags & 0x80) {
2246             /* skip event id */
2247             p += 2;
2248         }
2249         if (flags & 0x40) {
2250             if (buf_end - p < 1)
2251                 return;
2252 #if FF_API_AFD
2253 FF_DISABLE_DEPRECATION_WARNINGS
2254             avctx->dtg_active_format = p[0] & 0x0f;
2255 FF_ENABLE_DEPRECATION_WARNINGS
2256 #endif /* FF_API_AFD */
2257             s1->has_afd = 1;
2258             s1->afd     = p[0] & 0x0f;
2259         }
2260     } else if (buf_end - p >= 6 &&
2261                p[0] == 'J' && p[1] == 'P' && p[2] == '3' && p[3] == 'D' &&
2262                p[4] == 0x03) { // S3D_video_format_length
2263         // the 0x7F mask ignores the reserved_bit value
2264         const uint8_t S3D_video_format_type = p[5] & 0x7F;
2265
2266         if (S3D_video_format_type == 0x03 ||
2267             S3D_video_format_type == 0x04 ||
2268             S3D_video_format_type == 0x08 ||
2269             S3D_video_format_type == 0x23) {
2270
2271             s1->has_stereo3d = 1;
2272
2273             switch (S3D_video_format_type) {
2274             case 0x03:
2275                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE;
2276                 break;
2277             case 0x04:
2278                 s1->stereo3d.type = AV_STEREO3D_TOPBOTTOM;
2279                 break;
2280             case 0x08:
2281                 s1->stereo3d.type = AV_STEREO3D_2D;
2282                 break;
2283             case 0x23:
2284                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE_QUINCUNX;
2285                 break;
2286             }
2287         }
2288     } else if (mpeg_decode_a53_cc(avctx, p, buf_size)) {
2289         return;
2290     }
2291 }
2292
2293 static void mpeg_decode_gop(AVCodecContext *avctx,
2294                             const uint8_t *buf, int buf_size)
2295 {
2296     Mpeg1Context *s1  = avctx->priv_data;
2297     MpegEncContext *s = &s1->mpeg_enc_ctx;
2298
2299     int time_code_hours, time_code_minutes;
2300     int time_code_seconds, time_code_pictures;
2301     int broken_link;
2302
2303     init_get_bits(&s->gb, buf, buf_size * 8);
2304
2305     skip_bits1(&s->gb); /* drop_frame_flag */
2306
2307     time_code_hours   = get_bits(&s->gb, 5);
2308     time_code_minutes = get_bits(&s->gb, 6);
2309     skip_bits1(&s->gb); // marker bit
2310     time_code_seconds  = get_bits(&s->gb, 6);
2311     time_code_pictures = get_bits(&s->gb, 6);
2312
2313     s1->closed_gop = get_bits1(&s->gb);
2314     /* broken_link indicate that after editing the
2315      * reference frames of the first B-Frames after GOP I-Frame
2316      * are missing (open gop) */
2317     broken_link = get_bits1(&s->gb);
2318
2319     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2320         av_log(s->avctx, AV_LOG_DEBUG,
2321                "GOP (%2d:%02d:%02d.[%02d]) closed_gop=%d broken_link=%d\n",
2322                time_code_hours, time_code_minutes, time_code_seconds,
2323                time_code_pictures, s1->closed_gop, broken_link);
2324 }
2325
2326 static int decode_chunks(AVCodecContext *avctx, AVFrame *picture,
2327                          int *got_output, const uint8_t *buf, int buf_size)
2328 {
2329     Mpeg1Context *s = avctx->priv_data;
2330     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2331     const uint8_t *buf_ptr = buf;
2332     const uint8_t *buf_end = buf + buf_size;
2333     int ret, input_size;
2334     int last_code = 0, skip_frame = 0;
2335
2336     for (;;) {
2337         /* find next start code */
2338         uint32_t start_code = -1;
2339         buf_ptr = avpriv_find_start_code(buf_ptr, buf_end, &start_code);
2340         if (start_code > 0x1ff) {
2341             if (!skip_frame) {
2342                 if (HAVE_THREADS &&
2343                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2344                     !avctx->hwaccel) {
2345                     int i;
2346
2347                     avctx->execute(avctx, slice_decode_thread,
2348                                    &s2->thread_context[0], NULL,
2349                                    s->slice_count, sizeof(void *));
2350                     for (i = 0; i < s->slice_count; i++)
2351                         s2->er.error_count += s2->thread_context[i]->er.error_count;
2352                 }
2353
2354                 ret = slice_end(avctx, picture);
2355                 if (ret < 0)
2356                     return ret;
2357                 else if (ret) {
2358                     // FIXME: merge with the stuff in mpeg_decode_slice
2359                     if (s2->last_picture_ptr || s2->low_delay)
2360                         *got_output = 1;
2361                 }
2362             }
2363             s2->pict_type = 0;
2364             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2365         }
2366
2367         input_size = buf_end - buf_ptr;
2368
2369         if (avctx->debug & FF_DEBUG_STARTCODE)
2370             av_log(avctx, AV_LOG_DEBUG, "%3"PRIX32" at %td left %d\n",
2371                    start_code, buf_ptr - buf, input_size);
2372
2373         /* prepare data for next start code */
2374         switch (start_code) {
2375         case SEQ_START_CODE:
2376             if (last_code == 0) {
2377                 mpeg1_decode_sequence(avctx, buf_ptr, input_size);
2378                 s->sync = 1;
2379             } else {
2380                 av_log(avctx, AV_LOG_ERROR,
2381                        "ignoring SEQ_START_CODE after %X\n", last_code);
2382                 if (avctx->err_recognition & AV_EF_EXPLODE)
2383                     return AVERROR_INVALIDDATA;
2384             }
2385             break;
2386
2387         case PICTURE_START_CODE:
2388             if (s2->width <= 0 || s2->height <= 0) {
2389                 av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions %dx%d.\n",
2390                        s2->width, s2->height);
2391                 return AVERROR_INVALIDDATA;
2392             }
2393
2394             if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) &&
2395                 !avctx->hwaccel && s->slice_count) {
2396                 int i;
2397
2398                 avctx->execute(avctx, slice_decode_thread,
2399                                s2->thread_context, NULL,
2400                                s->slice_count, sizeof(void *));
2401                 for (i = 0; i < s->slice_count; i++)
2402                     s2->er.error_count += s2->thread_context[i]->er.error_count;
2403                 s->slice_count = 0;
2404             }
2405             if (last_code == 0 || last_code == SLICE_MIN_START_CODE) {
2406                 ret = mpeg_decode_postinit(avctx);
2407                 if (ret < 0) {
2408                     av_log(avctx, AV_LOG_ERROR,
2409                            "mpeg_decode_postinit() failure\n");
2410                     return ret;
2411                 }
2412
2413                 /* We have a complete image: we try to decompress it. */
2414                 if (mpeg1_decode_picture(avctx, buf_ptr, input_size) < 0)
2415                     s2->pict_type = 0;
2416                 s->first_slice = 1;
2417                 last_code      = PICTURE_START_CODE;
2418             } else {
2419                 av_log(avctx, AV_LOG_ERROR,
2420                        "ignoring pic after %X\n", last_code);
2421                 if (avctx->err_recognition & AV_EF_EXPLODE)
2422                     return AVERROR_INVALIDDATA;
2423             }
2424             break;
2425         case EXT_START_CODE:
2426             init_get_bits(&s2->gb, buf_ptr, input_size * 8);
2427
2428             switch (get_bits(&s2->gb, 4)) {
2429             case 0x1:
2430                 if (last_code == 0) {
2431                     mpeg_decode_sequence_extension(s);
2432                 } else {
2433                     av_log(avctx, AV_LOG_ERROR,
2434                            "ignoring seq ext after %X\n", last_code);
2435                     if (avctx->err_recognition & AV_EF_EXPLODE)
2436                         return AVERROR_INVALIDDATA;
2437                 }
2438                 break;
2439             case 0x2:
2440                 mpeg_decode_sequence_display_extension(s);
2441                 break;
2442             case 0x3:
2443                 mpeg_decode_quant_matrix_extension(s2);
2444                 break;
2445             case 0x7:
2446                 mpeg_decode_picture_display_extension(s);
2447                 break;
2448             case 0x8:
2449                 if (last_code == PICTURE_START_CODE) {
2450                     mpeg_decode_picture_coding_extension(s);
2451                 } else {
2452                     av_log(avctx, AV_LOG_ERROR,
2453                            "ignoring pic cod ext after %X\n", last_code);
2454                     if (avctx->err_recognition & AV_EF_EXPLODE)
2455                         return AVERROR_INVALIDDATA;
2456                 }
2457                 break;
2458             }
2459             break;
2460         case USER_START_CODE:
2461             mpeg_decode_user_data(avctx, buf_ptr, input_size);
2462             break;
2463         case GOP_START_CODE:
2464             if (last_code == 0) {
2465                 s2->first_field = 0;
2466                 mpeg_decode_gop(avctx, buf_ptr, input_size);
2467                 s->sync = 1;
2468             } else {
2469                 av_log(avctx, AV_LOG_ERROR,
2470                        "ignoring GOP_START_CODE after %X\n", last_code);
2471                 if (avctx->err_recognition & AV_EF_EXPLODE)
2472                     return AVERROR_INVALIDDATA;
2473             }
2474             break;
2475         default:
2476             if (start_code >= SLICE_MIN_START_CODE &&
2477                 start_code <= SLICE_MAX_START_CODE && last_code != 0) {
2478                 const int field_pic = s2->picture_structure != PICT_FRAME;
2479                 int mb_y = (start_code - SLICE_MIN_START_CODE) << field_pic;
2480                 last_code = SLICE_MIN_START_CODE;
2481
2482                 if (s2->picture_structure == PICT_BOTTOM_FIELD)
2483                     mb_y++;
2484
2485                 if (mb_y >= s2->mb_height) {
2486                     av_log(s2->avctx, AV_LOG_ERROR,
2487                            "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
2488                     return -1;
2489                 }
2490
2491                 if (!s2->last_picture_ptr) {
2492                     /* Skip B-frames if we do not have reference frames and
2493                      * GOP is not closed. */
2494                     if (s2->pict_type == AV_PICTURE_TYPE_B) {
2495                         if (!s->closed_gop) {
2496                             skip_frame = 1;
2497                             break;
2498                         }
2499                     }
2500                 }
2501                 if (s2->pict_type == AV_PICTURE_TYPE_I)
2502                     s->sync = 1;
2503                 if (!s2->next_picture_ptr) {
2504                     /* Skip P-frames if we do not have a reference frame or
2505                      * we have an invalid header. */
2506                     if (s2->pict_type == AV_PICTURE_TYPE_P && !s->sync) {
2507                         skip_frame = 1;
2508                         break;
2509                     }
2510                 }
2511                 if ((avctx->skip_frame >= AVDISCARD_NONREF &&
2512                      s2->pict_type == AV_PICTURE_TYPE_B) ||
2513                     (avctx->skip_frame >= AVDISCARD_NONKEY &&
2514                      s2->pict_type != AV_PICTURE_TYPE_I) ||
2515                     avctx->skip_frame >= AVDISCARD_ALL) {
2516                     skip_frame = 1;
2517                     break;
2518                 }
2519
2520                 if (!s->mpeg_enc_ctx_allocated)
2521                     break;
2522
2523                 if (s2->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
2524                     if (mb_y < avctx->skip_top ||
2525                         mb_y >= s2->mb_height - avctx->skip_bottom)
2526                         break;
2527                 }
2528
2529                 if (!s2->pict_type) {
2530                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2531                     if (avctx->err_recognition & AV_EF_EXPLODE)
2532                         return AVERROR_INVALIDDATA;
2533                     break;
2534                 }
2535
2536                 if (s->first_slice) {
2537                     skip_frame     = 0;
2538                     s->first_slice = 0;
2539                     if (mpeg_field_start(s2, buf, buf_size) < 0)
2540                         return -1;
2541                 }
2542                 if (!s2->current_picture_ptr) {
2543                     av_log(avctx, AV_LOG_ERROR,
2544                            "current_picture not initialized\n");
2545                     return AVERROR_INVALIDDATA;
2546                 }
2547
2548                 if (HAVE_THREADS &&
2549                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2550                     !avctx->hwaccel) {
2551                     int threshold = (s2->mb_height * s->slice_count +
2552                                      s2->slice_context_count / 2) /
2553                                     s2->slice_context_count;
2554                     if (threshold <= mb_y) {
2555                         MpegEncContext *thread_context = s2->thread_context[s->slice_count];
2556
2557                         thread_context->start_mb_y = mb_y;
2558                         thread_context->end_mb_y   = s2->mb_height;
2559                         if (s->slice_count) {
2560                             s2->thread_context[s->slice_count - 1]->end_mb_y = mb_y;
2561                             ret = ff_update_duplicate_context(thread_context, s2);
2562                             if (ret < 0)
2563                                 return ret;
2564                         }
2565                         init_get_bits(&thread_context->gb, buf_ptr, input_size * 8);
2566                         s->slice_count++;
2567                     }
2568                     buf_ptr += 2; // FIXME add minimum number of bytes per slice
2569                 } else {
2570                     ret = mpeg_decode_slice(s2, mb_y, &buf_ptr, input_size);
2571                     emms_c();
2572
2573                     if (ret < 0) {
2574                         if (avctx->err_recognition & AV_EF_EXPLODE)
2575                             return ret;
2576                         if (s2->resync_mb_x >= 0 && s2->resync_mb_y >= 0)
2577                             ff_er_add_slice(&s2->er, s2->resync_mb_x,
2578                                             s2->resync_mb_y, s2->mb_x, s2->mb_y,
2579                                             ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2580                     } else {
2581                         ff_er_add_slice(&s2->er, s2->resync_mb_x,
2582                                         s2->resync_mb_y, s2->mb_x - 1, s2->mb_y,
2583                                         ER_AC_END | ER_DC_END | ER_MV_END);
2584                     }
2585                 }
2586             }
2587             break;
2588         }
2589     }
2590 }
2591
2592 static int mpeg_decode_frame(AVCodecContext *avctx, void *data,
2593                              int *got_output, AVPacket *avpkt)
2594 {
2595     const uint8_t *buf = avpkt->data;
2596     int buf_size = avpkt->size;
2597     Mpeg1Context *s = avctx->priv_data;
2598     AVFrame *picture = data;
2599     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2600     av_dlog(avctx, "fill_buffer\n");
2601
2602     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2603         /* special case for last picture */
2604         if (s2->low_delay == 0 && s2->next_picture_ptr) {
2605             int ret = av_frame_ref(picture, s2->next_picture_ptr->f);
2606             if (ret < 0)
2607                 return ret;
2608
2609             s2->next_picture_ptr = NULL;
2610
2611             *got_output = 1;
2612         }
2613         return buf_size;
2614     }
2615
2616     if (s2->flags & CODEC_FLAG_TRUNCATED) {
2617         int next = ff_mpeg1_find_frame_end(&s2->parse_context, buf,
2618                                            buf_size, NULL);
2619
2620         if (ff_combine_frame(&s2->parse_context, next,
2621                              (const uint8_t **) &buf, &buf_size) < 0)
2622             return buf_size;
2623     }
2624
2625     if (s->mpeg_enc_ctx_allocated == 0 && avctx->codec_tag == AV_RL32("VCR2"))
2626         vcr2_init_sequence(avctx);
2627
2628     s->slice_count = 0;
2629
2630     if (avctx->extradata && !s->extradata_decoded) {
2631         int ret = decode_chunks(avctx, picture, got_output,
2632                                 avctx->extradata, avctx->extradata_size);
2633         s->extradata_decoded = 1;
2634         if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
2635             return ret;
2636     }
2637
2638     return decode_chunks(avctx, picture, got_output, buf, buf_size);
2639 }
2640
2641 static void flush(AVCodecContext *avctx)
2642 {
2643     Mpeg1Context *s = avctx->priv_data;
2644
2645     s->sync       = 0;
2646     s->closed_gop = 0;
2647
2648     ff_mpeg_flush(avctx);
2649 }
2650
2651 static av_cold int mpeg_decode_end(AVCodecContext *avctx)
2652 {
2653     Mpeg1Context *s = avctx->priv_data;
2654
2655     if (s->mpeg_enc_ctx_allocated)
2656         ff_mpv_common_end(&s->mpeg_enc_ctx);
2657     av_freep(&s->a53_caption);
2658     return 0;
2659 }
2660
2661 static const AVProfile mpeg2_video_profiles[] = {
2662     { FF_PROFILE_MPEG2_422,          "4:2:2"              },
2663     { FF_PROFILE_MPEG2_HIGH,         "High"               },
2664     { FF_PROFILE_MPEG2_SS,           "Spatially Scalable" },
2665     { FF_PROFILE_MPEG2_SNR_SCALABLE, "SNR Scalable"       },
2666     { FF_PROFILE_MPEG2_MAIN,         "Main"               },
2667     { FF_PROFILE_MPEG2_SIMPLE,       "Simple"             },
2668     { FF_PROFILE_RESERVED,           "Reserved"           },
2669     { FF_PROFILE_RESERVED,           "Reserved"           },
2670     { FF_PROFILE_UNKNOWN                                  },
2671 };
2672
2673 AVCodec ff_mpeg1video_decoder = {
2674     .name                  = "mpeg1video",
2675     .long_name             = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2676     .type                  = AVMEDIA_TYPE_VIDEO,
2677     .id                    = AV_CODEC_ID_MPEG1VIDEO,
2678     .priv_data_size        = sizeof(Mpeg1Context),
2679     .init                  = mpeg_decode_init,
2680     .close                 = mpeg_decode_end,
2681     .decode                = mpeg_decode_frame,
2682     .capabilities          = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2683                              CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2684                              CODEC_CAP_SLICE_THREADS,
2685     .flush                 = flush,
2686     .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg_decode_update_thread_context)
2687 };
2688
2689 AVCodec ff_mpeg2video_decoder = {
2690     .name           = "mpeg2video",
2691     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2692     .type           = AVMEDIA_TYPE_VIDEO,
2693     .id             = AV_CODEC_ID_MPEG2VIDEO,
2694     .priv_data_size = sizeof(Mpeg1Context),
2695     .init           = mpeg_decode_init,
2696     .close          = mpeg_decode_end,
2697     .decode         = mpeg_decode_frame,
2698     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2699                       CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2700                       CODEC_CAP_SLICE_THREADS,
2701     .flush          = flush,
2702     .profiles       = NULL_IF_CONFIG_SMALL(mpeg2_video_profiles),
2703 };
2704
2705 #if FF_API_XVMC
2706 #if CONFIG_MPEG_XVMC_DECODER
2707 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx)
2708 {
2709     if (avctx->active_thread_type & FF_THREAD_SLICE)
2710         return -1;
2711     if (!(avctx->slice_flags & SLICE_FLAG_CODED_ORDER))
2712         return -1;
2713     if (!(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
2714         av_dlog(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2715     }
2716     mpeg_decode_init(avctx);
2717
2718     avctx->pix_fmt           = AV_PIX_FMT_XVMC_MPEG2_IDCT;
2719     avctx->xvmc_acceleration = 2; // 2 - the blocks are packed!
2720
2721     return 0;
2722 }
2723
2724 AVCodec ff_mpeg_xvmc_decoder = {
2725     .name           = "mpegvideo_xvmc",
2726     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
2727     .type           = AVMEDIA_TYPE_VIDEO,
2728     .id             = AV_CODEC_ID_MPEG2VIDEO_XVMC,
2729     .priv_data_size = sizeof(Mpeg1Context),
2730     .init           = mpeg_mc_decode_init,
2731     .close          = mpeg_decode_end,
2732     .decode         = mpeg_decode_frame,
2733     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2734                       CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
2735     .flush          = flush,
2736 };
2737
2738 #endif
2739 #endif /* FF_API_XVMC */